SURGICAL ANATOMY

I INSCRIBE THIS WORK TO
THE GENTLEMEN WITH WHOM AS A FELLOW-STUDENT I WAS ASSOCIATED
AT THE
London University College:

AND IN AN ESPECIAL MANNER, IN THEIR NAME AS WELL AS MY OWN, I AVAIL MYSELF OF
THE OPPORTUNITY TO RECORD,
ON THIS PAGE,
ALBEIT IN CHARACTERS LESS IMPRESSIVE THAN THOSE WHICH ARE WRITTEN
ON THE LIVING TABLET OF MEMORY,
THE DEBT OF GRATITUDE WHICH WE OWE
TO THE LATE

SAMUEL COOPER, F.R.S., AND ROBERT LISTON, F.R.S.,

TWO AMONG THE MANY DISTINGUISHED PROFESSORS OF THAT INSTITUTION,
WHOSE PUPILS WE HAVE BEEN,
AND FROM WHOM WE INHERIT THAT BETTER POSSESSION THAN LIFE ITSELF,
AN ASPIRATION FOR THE LIGHT OF SCIENCE.

JOSEPH MACLISE.

PREFACE.

The object of this work is to present to the student of medicine and the
practitioner removed from the schools, a series of dissections demonstrative of
the relative anatomy of the principal regions of the human body. Whatever title
may most fittingly apply to a work with this intent, whether it had better be
styled surgical or medical, regional, relative, descriptive, or topographical
anatomy, will matter little, provided its more salient or prominent character
be manifested in its own form and feature. The work, as I have designed it,
will itself show that my intent has been to base the practical upon the
anatomical, and to unite these wherever a mutual dependence was apparent.

That department of anatomical research to which the name topographical strictly
applies, as confining itself to the mere account of the form and relative
location of the several organs comprising the animal body, is almost wholly
isolated from the main questions of physiological and transcendental interest,
and cannot, therefore, be supposed to speak in those comprehensive views which
anatomy, taken in its widest signification as a science, necessarily includes.
While the anatomist contents himself with describing the form and position of
organs as they appear exposed, layer after layer, by his dissecting
instruments, he does not pretend to soar any higher in the region of science
than the humble level of other mechanical arts, which merely appreciate the
fitting arrangement of things relative to one another, and combinative to the
whole design of the form or machine of whatever species this may be, whether
organic or inorganic. The descriptive anatomist of the human body aims at no
higher walk in science than this, and hence his nomenclature is, as it is, a
barbarous jargon of words, barren of all truthful signification, inconsonant
with nature, and blindly irrespective of the cognitio certa ex principiis
certis exorta.

Still, however, this anatomy of form, although so much requiring purification
of its nomenclature, in order to clothe it in the high reaching dignity of a
science, does not disturb the medical or surgical practitioner, so far as
their wants are concerned. Although it may, and actually does, trammel
the votary who aspires to the higher generalizations and the development of a
law of formation, yet, as this is not the object of the surgical anatomist, the
nomenclature, such as it is, will answer conveniently enough the present
purpose.

The anatomy of the human form, contemplated in reference to that of all other
species of animals to which it bears comparison, constitutes the study of the
comparative anatomist, and, as such, establishes the science in its full
intent. But the anatomy of the human figure, considered as a species, per
se, is confessedly the humblest walk of the understanding in a subject
which, as anatomy, is relationary, and branches far and wide through all the
domain of an animal kingdom. While restricted to the study of the isolated
human species, the cramped judgment wastes in such narrow confine; whereas, in
the expansive gaze over all allying and allied species, the intellect bodies
forth to its vision the full appointed form of natural majesty; and after
having experienced the manifold analogies and differentials of the many, is
thereby enabled, when it returns to the study of the one, to view this
one of human type under manifold points of interest, to the appreciation
of which the understanding never wakens otherwise. If it did not happen that
the study of the human form (confined to itself) had some practical bearing,
such study could not deserve the name of anatomical, while anatomical means
comparative, and whilst comparison implies inductive reasoning.

However, practical anatomy, such as it is, is concerned with an exact knowledge
of the relationship of organs as they stand in reference to each other, and to
the whole design of which these organs are the integral parts. The figure, the
capacity, and the contents of the thoracic and abdominal cavities, become a
study of not more urgent concernment to the physician, than are the regions
named cervical, axillary, inguinal, &c., to the surgeon. He who would
combine both modes of a relationary practice, such as that of medicine and
surgery, should be well acquainted with the form and structures characteristic
of all regions of the human body; and it may be doubted whether he who pursues
either mode of practice, wholly exclusive of the other, can do so with honest
purpose and large range of understanding, if he be not equally well acquainted
with the subject matter of both. It is, in fact, more triflingly fashionable
than soundly reasonable, to seek to define the line of demarcation between the
special callings of medicine and surgery, for it will ever be as vain an
endeavour to separate the one from the other without extinguishing the vitality
of both, as it would be to sunder the trunk from the head, and give to each a
separate living existence. The necessary division of labour is the only reason
that can be advanced in excuse of specialisms; but it will be readily agreed
to, that that practitioner who has first laid within himself the foundation of
a general knowledge of matters relationary to his subject, will always be found
to pursue the speciality according to the light of reason and science.

Anatomy—the  the knowledge based on principle—is the
foundation of the curative art, cultivated as a science in all its branchings;
and comparison is the nurse of reason, which we are fain to make our guide in
bringing the practical to bear productively. The human body, in a state of
health, is the standard whereunto we compare the same body in a state of
disease. The knowledge of the latter can only exist by the knowledge of the
former, and by the comparison of both.

Comparison may be fairly termed the pioneer to all certain knowledge. It is a
potent instrument—the only one, in the hands of the pathologist, as well as in
those of the philosophic generalizer of anatomical facts, gathered through the
extended survey of an animal kingdom. We best recognise the condition of a
dislocated joint after we have become well acquainted with the contour of its
normal state; all abnormal conditions are best understood by a knowledge of
what we know to be normal character. Every anatomist is a comparer, in a
greater or lesser degree; and he is the greatest anatomist who compares the
most generally.

Impressed with this belief, I have laid particular emphasis on imitating the
character of the normal form of the human figure, taken as a whole; that of its
several regions as parts of this whole, and that of the various organs
(contained within those regions) as its integrals or elements. And in order to
present this subject of relative anatomy in more vivid reality to the
understanding of the student, I have chosen the medium of illustrating by
figure rather than by that of written language, which latter, taken alone, is
almost impotent in a study of this nature.

It is wholly impossible for anyone to describe form in words without the aid of
figures. Even the mathematical strength of Euclid would avail nothing, if shorn
of his diagrams. The professorial robe is impotent without its diagrams.
Anatomy being a science existing by demonstration, (for as much as form in its
actuality is the language of nature,) must be discoursed of by the
instrumentality of figure.

An anatomical illustration enters the understanding straight-forward in a
direct passage, and is almost independent of the aid of written language. A
picture of form is a proposition which solves itself. It is an axiom
encompassed in a frame-work of self-evident truth. The best substitute for
Nature herself, upon which to teach the knowledge of her, is an exact
representation of her form.

Every surgical anatomist will (if he examine himself) perceive that, previously
to undertaking the performance of an operation upon the living body, he stands
reassured and self-reliant in that degree in which he is capable of conjuring
up before his mental vision a distinct picture of his subject. Mr. Liston could
draw the same anatomical picture mentally which Sir Charles Bell’s handicraft
could draw in reality of form and figure. Scarpa was his own draughtsman.

If there may be any novelty now-a-days possible to be recognised upon the
out-trodden track of human relative anatomy, it can only be in truthful and
well-planned illustration. Under this view alone may the anatomist plead an
excuse for reiterating a theme which the beautiful works of Cowper, Haller,
Hunter, Scarpa, Soemmering, and others, have dealt out so respectably. Except
the human anatomist turns now to what he terms the practical ends of his study,
and marshals his little knowledge to bear upon those ends, one may proclaim
anthropotomy to have worn itself out. Dissection can do no more, except to
repeat Cruveilhier. And that which Cruveilhier has done for human anatomy,
Muller has completed for the physiological interpretation of human anatomy;
Burdach has philosophised, and Magendie has experimented to the full upon this
theme, so far as it would permit. All have pushed the subject to its furthest
limits, in one aspect of view. The narrow circle is footworn. All the needful
facts are long since gathered, sown, and known. We have been seekers after
those facts from the days of Aristotle. Are we to put off the day of attempting
interpretation for three thousand years more, to allow the human physiologist
time to slice the brain into more delicate atoms than he has done hitherto, in
order to coin more names, and swell the dictionary? No! The work must now be
retrospective, if we would render true knowledge progressive. It is not a list
of new and disjointed facts that Science at present thirsts for; but she is
impressed with the conviction that her wants can alone be supplied by the
creation of a new and truthful theory,—a generalization which the facts already
known are sufficient to supply, if they were well ordered according to their
natural relationship and mutual dependence. “Le temps viendra peut-etre,” says
Fontenelle, “que l’on joindra en un corps regulier ces membres epars; et, s’ils
sont tels qu’on le souhaite, ils s’assembleront en quelque sorte d’eux-memes.
Plusieurs verites separees, des qu’elles sont en assez grand nombre, offrent si
vivement a l’esprit leurs rapports et leur mutuelle dependance, qu’il semble
qu’apres les avoir detachees par une espece de violence les unes des autres,
elles cherchent naturellement a se reunir.”—(Preface sur l’utilite des
Sciences, &c.)

The comparison of facts already known must henceforward be the scalpel which we
are to take in hand. We must return by the same road on which we set out, and
reexamine the things and phenomena which, as novices, we passed by too lightly.
The travelled experience may now sit down and contemplate.

That which I have said and proved elsewhere in respect to the skeleton system
may, with equal truth, be remarked of the nervous system—namely, that the
question is not in how far does the limit of diversity extend through the
condition of an evidently common analogy, but by what rule or law the uniform
ens is rendered the diverse entity? The womb of anatomical science is pregnant
of the true interpretation of the law of unity in variety; but the
question is of longer duration than was the life of the progenitor. Though
Aristotle and Linnaeus, and Buffon and Cuvier, and Geoffroy St. Hilaire and
Leibnitz, and Gothe, have lived and spoken, yet the present state of knowledge
proclaims the Newton of physiology to be as yet unborn. The iron scalpel has
already made acquaintance with not only the greater parts, but even with the
infinitesimals of the human body; and reason, confined to this narrow range of
a subject, perceives herself to be imprisoned, and quenches her guiding light
in despair. Originality has outlived itself; and discovery is a long-forgotten
enterprise, except as pursued in the microcosm on the field of the microscope,
which, it must be confessed, has drawn forth demonstrations only commensurate
in importance with the magnitude of the littleness there seen.

The subject of our study, whichever it happen to be, may appear exhausted of
all interest, and the promise of valuable novelty, owing to two reasons:—It may
be, like descriptive human anatomy, so cold, poor and sterile in its own
nature, and so barren of product, that it will be impossible for even the
genius of Promethean fire to warm it; or else, like existing physiology, the
very point of view from which the mental eye surveys the theme, will blight the
fair prospect of truth, distort induction, and clog up the paces of
ratiocination. The physiologist of the present day is too little of a
comparative anatomist, and far too closely enveloped in the absurd jargon of
the anthropotomist, ever to hope to reveal any great truth for science, and
dispel the mists which still hang over the phenomena of the nervous system. He
is steeped too deeply in the base nomenclature of the antique school, and too
indolent to question the import of Pons, Commissure, Island, Taenia, Nates,
Testes, Cornu, Hippocamp, Thalamus, Vermes, Arbor Vitro, Respiratory Tract,
Ganglia of Increase, and all such phrase of unmeaning sound, ever to be
productive of lucid interpretation of the cerebro-spinal ens. Custom alone
sanctions his use of such names; but

“Custom calls him to it!
What custom wills; should custom always do it,
The dust on antique time would lie unswept,
And mountainous error be too highly heaped,
For truth to overpeer.”

Of the illustrations of this work I may state, in guarantee of their anatomical
accuracy, that they have been made by myself from my own dissections, first
planned at the London University College, and afterwards realised at the Ecole
Pratique, and School of Anatomy adjoining the Hospital La Pitie, Paris, a few
years since. As far as the subject of relative anatomy could admit of novel
treatment, rigidly confined to facts unalterable, I have endeavoured to give
it.

The unbroken surface of the human figure is as a map to the surgeon,
explanatory of the anatomy arranged beneath; and I have therefore left appended
to the dissected regions as much of the undissected as was necessary. My object
was to indicate the interior through the superficies, and thereby illustrate
the whole living body which concerns surgery, through its dissected dead
counterfeit. We dissect the dead animal body in order to furnish the memory
with as clear an account of the structure contained in its living
representative, which we are not allowed to analyse, as if this latter were
perfectly translucent, and directly demonstrative of its component parts.

J. M

TABLE OF CONTENTS.

PREFACE
INTRODUCTORY TO THE STUDY OF ANATOMY AS A SCIENCE.

COMMENTARY ON PLATES 1 & 2

THE FORM OF THE THORAX, AND THE RELATIVE POSITION OF ITS CONTAINED PARTS—THE
LUNGS, HEART, AND LARGER BLOOD VESSELS.

The structure, mechanism, and respiratory motions of the thoracic apparatus.
Its varieties in form, according to age and sex. Its deformities. Applications
to the study of physical diagnosis.

COMMENTARY ON PLATES 3 & 4

THE SURGICAL FORM OF THE SUPERFICIAL, CERVICAL, AND FACIAL REGIONS, AND THE
RELATIVE POSITION OF THE PRINCIPAL BLOOD VESSELS, NERVES, ETC.

The cervical surgical triangles considered in reference to the position of the
subclavian and carotid vessels, &c. Venesection in respect to the external
jugular vein. Anatomical reasons for avoiding transverse incisions in the neck.
The parts endangered in surgical operations on the parotid and submaxillary
glands, &c.

COMMENTARY ON PLATES 5 & 6

THE SURGICAL FORM OF THE DEEP CERVICAL AND FACIAL REGIONS, AND THE RELATIVE
POSITION OF THE PRINCIPAL BLOOD VESSELS, NERVES, ETC.

The course of the carotid and subclavian vessels in reference to each other, to
the surface, and to their respective surgical triangles. Differences in the
form of the neck in individuals of different age and sex. Special relations of
the vessels. Physiological remarks on the carotid artery. Peculiarities in the
relative position of the subclavian artery.

COMMENTARY ON PLATES 7 & 8

THE SURGICAL DISSECTION OF THE SUBCLAVIAN AND CAROTID REGIONS, AND THE RELATIVE
ANATOMY OF THEIR CONTENTS.

General observations. Abnormal complications of the carotid and subclavian
arteries. Relative position of the vessels liable to change by the motions of
the head and shoulder. Necessity for a fixed surgical position in operations
affecting these vessels. The operations for tying the carotid or the subclavian
at different situations in cases of aneurism, &c. The operation for tying
the innominate artery. Reasons of the unfavourable results of this
proceeding.

COMMENTARY ON PLATES 9 & 10

THE SURGICAL DISSECTION OF THE EPISTERNAL OR TRACHEAL REGION, AND THE RELATIVE
POSITION OF ITS MAIN BLOOD VESSELS, NERVES, ETC.

Varieties of the primary aortic branches explained by the law of metamorphosis.
The structures at the median line of the neck. The operations of tracheotomy
and laryngotomy in the child and adult, The right and left brachio-cephalic
arteries and their varieties considered surgically.

COMMENTARY ON PLATES 11 & 12

THE SURGICAL DISSECTION OF THE AXILLARY AND BRACHIAL REGIONS, DISPLAYING THE
RELATIVE POSITION OF THEIR CONTAINED PARTS.

The operation for tying the axillary artery. Remarks on fractures of the
clavicle and dislocation of the humerus in reference to the axillary vessels.
The operation for tying the brachial artery near the axilla. Mode of
compressing this vessel against the humerus.

COMMENTARY ON PLATES 13 & 14

THE SURGICAL FORMS OF THE MALE AND FEMALE AXILLAE COMPARED.

The mammary and axillary glands in health and disease. Excision of these
glands. Axillary abscess. General surgical observations on the axilla.

COMMENTARY ON PLATES 15 & 16

THE SURGICAL DISSECTION OF THE BEND OF THE ELBOW AND THE FOREARM, SHOWING THE
RELATIVE POSITION OF THE VESSELS AND NERVES.

General remarks. Operation for tying the brachial artery at its middle and
lower thirds. Varieties of the brachial artery. Venesection at the bend of the
elbow. The radial and ulnar pulse. Operations for tying the radial and ulnar
arteries in several parts.

COMMENTARY ON PLATES 17, 18, & 19

THE SURGICAL DISSECTION OF THE WRIST AND HAND.

General observations. Superficial and deep palmar arches. Wounds of these
vessels requiring a ligature to be applied to both ends. General surgical
remarks on the arteries of the upper limb. Palmar abscess, &c.

COMMENTARY ON PLATES 20 & 21

THE RELATIVE POSITION OF THE CRANIAL, NASAL, ORAL, AND PHARYNGEAL CAVITIES,
ETC.

Fractures of the cranium, and the operation of trephining anatomically
considered. Instrumental measures in reference to the fauces, tonsils,
oesophagus, and lungs.

COMMENTARY ON PLATE 22

THE RELATIVE POSITION OF THE SUPERFICIAL ORGANS OF THE THORAX AND ABDOMEN.

Application to correct physical diagnosis. Changes in the relative position of
the organs during the respiratory motions. Changes effected by disease.
Physiological remarks on wounds of the thorax and on pleuritic effusion.
Symmetry of the organs, &c.

COMMENTARY ON PLATE 23

THE RELATIVE POSITION OF THE DEEPER ORGANS OF THE THORAX AND THOSE OF THE
ABDOMEN.

Of the heart in reference to auscultation and percussion. Of the lungs, ditto.
Relative capacity of the thorax and abdomen as influenced by the motions of the
diaphragm. Abdominal respiration. Physical causes of abdominal herniae.
Enlarged liver as affecting the capacity of the thorax and abdomen.
Physiological remarks on wounds of the lungs. Pneumothorax, emphysema,
&c.

COMMENTARY ON PLATE 24

THE RELATIONS OF THE PRINCIPAL BLOODVESSELS TO THE VISCERA OF THE
THORACICO-ABDOMINAL CAVITY.

Symmetrical arrangement of the vessels arising from the median
thoracico-abdominal aorta, &c. Special relations of the aorta. Aortic
sounds. Aortic aneurism and its effects on neighbouring organs. Paracentesis
thoracis. Physical causes of dropsy. Hepatic abscess. Chronic enlargements of
the liver and spleen as affecting the relative position of other parts. Biliary
concretions. Wounds of the intestines. Artificial anus.

COMMENTARY ON PLATE 25

THE RELATION OF THE PRINCIPAL BLOODVESSELS OF THE THORAX AND ABDOMEN TO THE
OSSEOUS SKELETON.

The vessels conforming to the shape of the skeleton. Analogy between the
branches arising from both ends of the aorta. Their normal and abnormal
conditions. Varieties as to the length of these arteries considered surgically.
Measurements of the abdomen and thorax compared. Anastomosing branches of the
thoracic and abdominal parts of the aorta.

COMMENTARY ON PLATE 26

THE RELATION OF THE INTERNAL PARTS TO THE EXTERNAL SURFACE.

In health and disease. Displacement of the lungs from pleuritic effusion.
Paracentesis thoracis. Hydrops pericardii. Puncturation. Abdominal and ovarian
dropsy as influencing the position of the viscera. Diagnosis of both dropsies.
Paracentesis abdominis. Vascular obstructions and their effects.

COMMENTARY ON PLATE 27

THE SURGICAL DISSECTION OF THE SUPERFICIAL PARTS AND BLOODVESSELS OF THE
INGUINO-FEMORAL REGION.

Physical causes of the greater frequency of inguinal and femoral herniae. The
surface considered in reference to the subjacent parts.

COMMENTARY ON PLATES 28 & 29

THE SURGICAL DISSECTION OF THE FIRST, SECOND, THIRD, AND FOURTH LAYERS OF THE
INGUINAL REGION, IN CONNEXION WITH THOSE OF THE THIGH.

The external abdominal ring and spermatic cord. Cremaster muscle—how formed.
The parts considered in reference to inguinal hernia. The saphenous opening,
spermatic cord, and femoral vessels in relation to femoral hernia.

COMMENTARY ON PLATES 30 & 31

THE SURGICAL DISSECTION OF THE FIFTH, SIXTH, SEVENTH, AND EIGHTH LAYERS OF THE
INGUINAL REGION, AND THEIR CONNEXION WITH THOSE OF THE THIGH.

The conjoined tendon, internal inguinal ring, and cremaster muscle, considered
in reference to the descent of the testicle and of the hernia. The structure
and direction of the inguinal canal.

COMMENTARY ON PLATES 32, 33, & 34

THE DISSECTION OF THE OBLIQUE OR EXTERNAL, AND OF THE DIRECT OR INTERNAL
INGUINAL HERNIA.

Their points of origin and their relations to the inguinal rings. The triangle
of Hesselbach. Investments and varieties of the external inguinal hernia, its
relations to the epigastric artery, and its position in the canal. Bubonocele,
complete and scrotal varieties in the male. Internal inguinal hernia considered
in reference to the same points. Corresponding varieties of both herniae in the
female.

COMMENTARY ON PLATES 35, 36, 37, & 38

THE DISTINCTIVE DIAGNOSIS BETWEEN EXTERNAL AND INTERNAL INGUINAL HERNIAE, THE
TAXIS, SEAT OF STRICTURE, AND THE OPERATION.

Both herniae compared as to position and structural characters. The
co-existence of both rendering diagnosis difficult. The oblique changing to the
direct hernia as to position, but not in relation to the epigastric artery. The
taxis performed in reference to the position of both as regards the canal and
abdominal rings. The seat of stricture varying. The sac. The lines of incision
required to avoid the epigastric artery. Necessity for opening the sac.

COMMENTARY ON PLATES 39 & 40

DEMONSTRATIONS OF THE NATURE OF CONGENITAL AND INFANTILE INGUINAL HERNIAE, AND
OF HYDROCELE.

Descent of the testicle. The testicle in the scrotum. Isolation of its tunica
vaginalis. The tunica vaginalis communicating with the abdomen. Sacculated
serous spermatic canal. Hydrocele of the isolated tunica vaginalis. Congenital
hernia and hydrocele. Infantile hernia. Oblique inguinal hernia. How formed and
characterized.

COMMENTARY ON PLATES 41 & 42

DEMONSTRATIONS OF THE ORIGIN AND PROGRESS OF INGUINAL HERNIAE IN GENERAL.

Formation of the serous sac. Formation of congenital hernia. Hernia in the
canal of Nuck. Formation of infantile hernia. Dilatation of the serous sac.
Funnel-shaped investments of the hernia. Descent of the hernia like that of the
testicle. Varieties of infantile hernia. Sacculated cord. Oblique internal
inguinal hernia—cannot be congenital. Varieties of internal hernia. Direct
external hernia. Varieties of the inguinal canal.

COMMENTARY ON PLATES 43 & 44

THE DISSECTION OF FEMORAL HERNIA AND THE SEAT OF STRICTURE.

Compared with the inguinal variety. Position and relations. Sheath of the
femoral vessels and of the hernia. Crural ring and canal. Formation of the sac.
Saphenous opening. Relations of the hernia. Varieties of the obturator and
epigastric arteries. Course of the hernia. Investments. Causes and situations
of the stricture.

COMMENTARY ON PLATES 45 & 46

DEMONSTRATIONS OF THE ORIGIN AND PROGRESS OF FEMORAL HERNIA; ITS DIAGNOSIS, THE
TAXIS, AND THE OPERATION.

Its course compared with that of the inguinal hernia. Its investments and
relations. Its diagnosis from inguinal hernia, &c. Its varieties. Mode of
performing the taxis according to the course of the hernia. The operation for
the strangulated condition. Proper lines in which incisions should be made.
Necessity for and mode of opening the sac.

COMMENTARY ON PLATE 47

THE SURGICAL DISSECTION OF THE PRINCIPAL BLOODVESSELS AND NERVES OF THE ILIAC
AND FEMORAL REGIONS.

The femoral triangle. Eligible place for tying the femoral artery. The
operations of Scarpa and Hunter. Remarks on the common femoral artery. Ligature
of the external iliac artery according to the seat of aneurism.

COMMENTARY ON PLATES 48 & 49

THE RELATIVE ANATOMY OF THE MALE PELVIC ORGANS.

Physiological remarks on the functions of the abdominal muscles. Effects of
spinal injuries on the processes of defecation and micturition. Function of the
bladder. Its change of form and position in various states. Relation to the
peritonaeum. Neck of the bladder. The prostate. Puncturation of the bladder by
the rectum. The pudic artery.

COMMENTARY ON PLATES 50 & 51

THE SURGICAL DISSECTION OF THE SUPERFICIAL STRUCTURES OF THE MALE PERINAEUM.

Remarks on the median line. Congenital malformations. Extravasation of urine
into the sac of the superficial fascia. Symmetry of the parts. Surgical
boundaries of the perinaeum. Median and lateral important parts to be avoided
in lithotomy, and the operation for fistula in ano.

COMMENTARY ON PLATES 52 & 53

THE SURGICAL DISSECTION OF THE DEEP STRUCTURES OF THE MALE PERINAEUM; THE
LATERAL OPERATION OF LITHOTOMY.

Relative position of the parts at the base of the bladder. Puncture of the
bladder through the rectum and of the urethra in the perinaeum. General rules
for lithotomy.

COMMENTARY ON PLATES 54, 55, & 56

THE SURGICAL DISSECTION OF THE MALE BLADDER AND URETHRA; LATERAL AND BILATERAL
LITHOTOMY COMPARED.

Lines of incision in both operations. Urethral muscles—their analogies and
significations. Direction, form, length, structure, &c., of the urethra at
different ages. Third lobe of the prostate. Physiological remarks. Trigone
vesical. Bas fond of the bladder. Natural form of the prostate at different
ages.

COMMENTARY ON PLATES 57 & 58

CONGENITAL AND PATHOLOGICAL DEFORMITIES OF THE PREPUCE AND URETHRA; STRICTURES
AND MECHANICAL OBSTRUCTIONS OF THE URETHRA.

General remarks. Congenital phymosis. Gonorrhoeal paraphymosis and phymosis.
Effect of circumcision. Protrusion of the glans through an ulcerated opening in
the prepuce. Congenital hypospadias. Ulcerated perforations of the urethra.
Congenital epispadias. Urethral fistula, stricture, and catheterism. Sacculated
urethra. Stricture opposite the bulb and the membranous portion of the urethra.
Observations respecting the frequency of stricture in these parts. Calculus at
the bulb. Polypus of the urethra. Calculus in its membranous portion. Stricture
midway between the meatus and bulb. Old callous stricture, its form, &c.
Spasmodic stricture of the urethra by the urethral muscles. Organic stricture.
Surgical observations.

COMMENTARY ON PLATES 59 & 60

THE VARIOUS FORMS AND POSITIONS OF STRICTURES AND OTHER OBSTRUCTIONS OF THE
URETHRA; FALSE PASSAGES; ENLARGEMENTS AND DEFORMITIES OF THE PROSTATE.

General remarks. Different forms of the organic stricture. Coexistence of
several. Prostatic abscess distorting and constricting the urethra. Perforation
of the prostate by catheters. Series of gradual enlargements of the third lobe
of the prostate. Distortion of the canal by the enlarged third lobe—by the
irregular enlargement of the three lobes—by a nipple-shaped excrescence at the
vesical orifice.

COMMENTARY ON PLATES 61 & 62

DEFORMITIES OF THE PROSTATE; DISTORTIONS AND OBSTRUCTIONS OF THE PROSTATIC
URETHRA.

Observations on the nature of the prostate—its signification. Cases of prostate
and bulb pouched by catheters. Obstructions of the vesical orifice. Sinuous
prostatic canal. Distortions of the vesical orifice. Large prostatic calculus.
Sacculated prostate. Triple prostatic urethra. Encrusted prostate. Fasciculated
bladder. Prostatic sac distinct from the bladder. Practical remarks. Impaction
of a large calculus in the prostate. Practical remarks.

COMMENTARY ON PLATES 63 & 64

DEFORMITIES OF THE URINARY BLADDER; THE OPERATIONS OF SOUNDING FOR STONE; OF
CATHETERISM AND OF PUNCTURING THE BLADDER ABOVE THE PUBES.

General remarks on the causes of the various deformities, and of the formation
of stone. Lithic diathesis—its signification. The sacculated bladder considered
in reference to sounding, to catheterism, to puncturation, and to lithotomy.
Polypi in the bladder. Dilated ureters. The operation of catheterism. General
rules to be followed. Remarks on the operation of puncturing the bladder above
the pubes.

COMMENTARY ON PLATES 65 & 66

THE SURGICAL DISSECTION OF THE POPLITEAL SPACE, AND THE POSTERIOR CRURAL
REGION.

Varieties of the popliteal and posterior crural vessels. Remarks on popliteal
aneurism, and the operation for tying the popliteal artery, in wounds of this
vessel. Wounds of the posterior crural arteries requiring double ligatures. The
operations necessary for reaching these vessels.

COMMENTARY ON PLATES 67 & 68

THE SURGICAL DISSECTION OF THE ANTERIOR CRURAL REGION; THE ANKLES AND THE FOOT.

Varieties of the anterior and posterior tibial and the peronaeal arteries. The
operations for tying these vessels in several situations. Practical
observations on wounds of the arteries of the leg and foot.

CONCLUDING COMMENTARY

ON THE FORM AND DISTRIBUTION OF THE VASCULAR SYSTEM AS A WHOLE; ANOMALIES;
RAMIFICATION; ANASTOMOSIS.

The double heart. Universal systemic capillary anastomosis. Its division, by
the median line, into two great lateral fields—those subdivided into two
systems or provinces—viz., pulmonary and systemic. Relation of pulmonary and
systemic circulating vessels. Motions of the heart. Circulation of the blood
through the lungs and system. Symmetry of the hearts and their vessels.
Development of the heart and primary vessels. Their stages of metamorphosis
simulating the permanent conditions of the parts in lower animals. The
primitive branchial arches undergoing metamorphosis. Completion of these
changes. Interpretation of the varieties of form in the heart and primary
vessels. Signification of their normal condition. The portal system no
exception to the law of vascular symmetry. Signification of the portal system.
The liver and spleen as homologous organs,—as parts of the same whole quantity.
Cardiac anastomosing vessels. Vasa vasorum. Anastomosing branches of the
systemic aorta considered in reference to the operations of arresting by
ligature the direct circulation through the arteries of the head, neck, upper
limbs, pelvis, and lower limbs. The collateral circulation. Practical
observations on the most eligible situations for tying each of the principal
vessels, as determined by the greatest number of their anastomosing branches on
either side of the ligature, and the largest amount of the collateral
circulation that may be thereby carried on for the support of distal parts.

COMMENTARY ON PLATES 1 & 2.

THE FORM OF THE THORACIC CAVITY, AND THE POSITION OF THE LUNGS, HEART, AND
LARGER BLOODVESSELS.

In the human body there does not exist any such space as cavity,
properly so called. Every space is occupied by its contents. The thoracic space
is completely filled by its viscera, which, in mass, take a perfect cast or
model of its interior. The thoracic viscera lie so closely to one another, that
they respectively influence the form and dimensions of each other. That space
which the lungs do not occupy is filled by the heart, &c., and vice
versa. The thoracic apparatus causes no vacuum by the acts of either
contraction or dilatation. Neither do the lungs or the heart. When any organ,
by its process of growth, or by its own functional act, forces a space for
itself, it immediately inhabits that space entirely at the expense of
neighbouring organs. When the heart dilates, the pulmonary space contracts; and
when the thoracic space increases, general space diminishes in the same ratio.

The mechanism of the functions of respiration and circulation consists, during
the life of the animal, in a constant oscillatory nisus to produce a
vacuum which it never establishes. These vital forces of the respiratory and
circulatory organs, so characteristic of the higher classes of animals, are
opposed to the general forces of surrounding nature. The former vainly strive
to make exception to the irrevocable law, that “nature abhors a vacuum.”
This act of opposition between both forces constitutes the respiratory act, and
thus the respiratory thoracic being (like a vibrating pendulum) manifests
respiratory motion, not as an effort of volition originating solely with
itself, but according to the measure of the force of either law; as entity is
relationary, so is functionality likewise. The being is functional by
relationship; and just as a pendulum is functional, by reason of the
counteraction of two opposing forces,—viz., the force of motion and the force
of gravity,—so is a thoracic cavity (considering it as a mechanical apparatus)
functional by two opposing forces—the vital force and the surrounding physical
force. The inspiration of thoracic space is the expiration of general space,
and reciprocally.

The thoracic space is a symmetrical enclosure originally, which aftercoming
necessities modify and distort in some degree. The spaces occupied by the
opposite lungs in the adult body do not exactly correspond as to capacity, O O,
Plate 1. Neither is the cardiac space, A E G D, Plate 1, which is traversed by
the common median line, symmetrical. The asymmetry of the lungs is mainly owing
to the form and position of the heart; for this organ inclines towards the left
thoracic side. The left lung is less in capacity than the right, by so much
space as the heart occupies in the left pulmonary side. The general form of the
thorax is that of a cone, I I N N, Plate 1, bicleft through its perpendicular
axis, H M. The line of bicleavage is exactly median, and passes through the
centre of the sternum in front, and the centres of the dorsal vertebral behind.
Between the dorsal vertebral and the sternum, the line of median cleavage is
maintained and sketched out in membrane. This membranous middle is formed by
the adjacent sides of the opposite pleural or enveloping bags in which the
lungs are enclosed. The heart, A, Plate 1, is developed between these two
pleural sacs, F F, and separates them from each other to a distance
corresponding to its own size. The adjacent sides of the two pleural sacs are
central to the thorax, and form that space which is called mediastinum; the
heart is located in this mediastinum, U E, Plate 1. The extent of the thoracic
region ranges perpendicularly from the root of the neck, Q, Plate 1, to
the roof of the abdomen—viz., the diaphragm, P, transversely from the
ribs of one side, I N, Plate 1, to those of the other, and
antero-posteriorly from the sternum, H M, to the vertebral column. All
this space is pulmonary, except the cardiac or median space, which, in addition
to the heart, A, Plate 1, and great bloodvessels, G C B, contains the
oesophagus, bronchi, &c. The ribs are the true enclosures of thoracic
space, and, generally, in mammalian forms, they fail or degenerate at that
region of the trunk which is not pulmonary or respiratory. In human anatomy, a
teleological reason is given for this—namely, that of the ribs being
mechanically subservient to the function of respiration alone. But the
transcendental anatomists interpret this fact otherwise, and refer it to the
operation of a higher law of formation.

The capacity of the thorax is influenced by the capacity of the abdomen and its
contents. In order to admit of full inspiration and pulmonary expansion, the
abdominal viscera recede in the same ratio as the lungs dilate. The diaphragm,
P P, Plate 1, or transverse musculo-membranous partition which divides the
pulmonary and alimentary cavities, is, by virtue of its situation, as
mechanically subservient to the abdomen as to the thorax. And under general
notice, it will appear that even the abdominal muscles are as directly related
to the respiratory act as those of the thorax. The connexion between functions
is as intimate and indissoluble as the connexion between organs in the same
body. There can be no more striking proof of the divinity of design than by
such revelations as anatomical science everywhere manifests in facts such as
this—viz., that each organ serves in most cases a double, and in many a triple
purpose, in the animal economy.

The apex of the lung projects into the root of the neck, even to a higher
level, Q, Plate 1, than that occupied by the sternal end of the clavicle, K. If
the point of a sword were pushed through the neck above the clavicle, at K,
Plate 1, it would penetrate the apex of the right lung, where the subclavian
artery, Q, Plate 1, arches over it. In connexion with this fact, I may mention
it as very probable that the bruit, or continuous murmur which we hear
through the stethoscope, in chlorotic females, is caused by the pulsation of
the subclavian artery against the top of the lung. The stays or girdle which
braces the loins of most women prevents the expansion of the thoracic
apparatus, naturally attained by the descent of the diaphragm; and hence, no
doubt, the lung will distend inordinately above towards the neck. It is an
interesting fact for those anatomists who study the higher generalizations of
their science, that at those very localities—viz., the neck and loins, where
the lungs by their own natural effort are prone to extend themselves in forced
inspiration—happen the “anomalous” creations of cervical and lumbar ribs. The
subclavian artery is occasionally complicated by the presence of these costal
appendages.

If the body be transfixed through any one of the intercostal spaces, the
instrument will surely wound some part of the lung. If the thorax be pierced
from any point whatever, provided the instrument be directed towards a common
centre, A, Plate 1, the lung will suffer lesion; for the heart is, almost
completely, in the healthy living body, enveloped in the lungs. So true is it
that all the costal region (the asternal as well as the sternal) is a pulmonary
enclosure, that any instrument which pierces intercostal space must wound the
lung.

As the sternal ribs degenerate into the “false” asternal or incomplete ribs
from before, obliquely backward down to the last dorsal vertebra, so the
thoracic space takes form. The lungs range through a much larger space,
therefore, posteriorly than they do anteriorly.

The form of the thorax, in relation to that of the abdomen, may be learned from
the fact that a gunshot, which shall enter a little below N, Plate 1, and,
after traversing the body transversely, shall pass out at a corresponding point
at the opposite side, would open the thorax and the abdomen into a common
cavity; for it would pierce the thorax at N, the arching diaphragm at the level
of M, and thereat enter the belly; then it would enter the thorax again at P,
and make exit below N, opposite. If a cutting instrument were passed
horizontally from before backward, a little below M, it would first open the
abdomen, then pierce the arching diaphragm, and pass into the thorax, opposite
the ninth or eighth dorsal vertebra.

The outward form or superficies masks in some degree the form of the interior.
The width of the thorax above does not exceed the diameter between the points I
I, of Plate 1, or the points W W, of Plate 2. If we make percussion directly
from before backwards at any place external to I, Plate 1, we do not render the
lung vibrative. The diameters between I I and N N, Plate 1, are not equal; and
these measures will indicate the form of the thorax in the living body, between
the shoulders above and the loins below.

The position of the heart in the thorax varies somewhat with several bodies.
The size of the heart, even in a state of perfect health, varies also in
subjects of corresponding ages, a condition which is often mistaken for
pathological. For the most part, its form occupies a space ranging from two or
three lines right of the right side of the sternum to the middle of the shafts
of the fifth and sixth ribs of the left side. In general, the length of the
osseous sternum gives the exact perpendicular range of the heart, together with
its great vessels.

The aorta, C, Plates 1 and 2, is behind the upper half of the sternum, from
which it is separated by the pericardium, D, Plate 1, the thin edge of the
lung, and the mediastinal pleurae, U E, Plate 1, &c. If the heart be
injected from the abdominal aorta, the aortal arch will flatten against the
sternum. Pulmonary space would not be opened by a penetrating instrument passed
into the root of the neck in the median line above the sternum, at L, Plate 1.
But the apices of both lungs would be wounded if the same instrument entered
deeply on either side of this median line at K K. An instrument which would
pierce the sternum opposite the insertion of the second, third, or fourth
costal cartilage, from H downwards, would transfix some part of the arch of the
aorta, C, Plate 1. The same instrument, if pushed horizontally backward through
the second, third, or fourth interspaces of the costal cartilages close to the
sternum, would wound, on the right of the sternal line, the vena cava superior,
G, Plate 1; on the left, the pulmonary artery, B, and the descending thoracic
aorta. In the healthy living body, the thoracic sounds heard in percussion, or
by means of the stethoscope, will vary according to the locality operated upon,
in consequence of the variable thickness of those structures (muscular and
osseous, &c.,) which invest the thoracic walls. Uniformity of sound must,
owing to these facts, be as materially interrupted, as it certainly is, in
consequence of the variable contents of the cavity. The variability of the
healthy thoracic sounds will, therefore, be too often likely to be mistaken for
that of disease, if we forget to admit these facts, as instanced in the former
state. Considering the form of the thoracic space in reference to the general
form of the trunk of the living body, I see reason to doubt whether the
practitioner can by any boasted delicacy of manipulation, detect an abnormal
state of the pulmonary organs by percussion, or the use of the stethoscope,
applied at those regions which he terms coracoid, scapulary, subclavian,
&c., if the line of his examination be directed from before backwards. The
scapula, covered by thick carneous masses, does not lie in the living body
directly upon the osseous-thorax, neither does the clavicle. As all
antero-posterior examination in reference to the lungs external to the points,
I I, between the shoulders cannot, in fact, concern the pulmonary organs, so it
cannot be diagnostic of their state either in health or disease. The
difficulties which oppose the practitioner’s examination of the state of the
thoracic contents are already numerous enough, independent of those which may
arise from unanatomical investigation.

DESCRIPTION OF PLATES 1 & 2.

PLATE 1.

A. Right ventricle of the heart.

B. Origin of pulmonary artery.

C. Commencement of the systemic aorta, ascending part of aortic arch.

D. Pericardium investing the heart and the origins of the great bloodvessels.

E. Mediastinal pleura, forming a second investment for the heart, bloodvessels,
&c.

F. Costal pleura, seen to be continuous above with that which forms the
mediastinum.

G. Vena cava superior, entering pericardium to join V, the right auricle.

H. Upper third of sternum.

I I. First ribs.

K K. Sternal ends of the clavicles.

L. Upper end of sternum.

M. Lower end of sternum.

N N. Fifth ribs.

O O. Collapsed lungs.

P P. Arching diaphragm.

Q. Subclavian artery.

R. Common carotid artery, at its division into internal and external carotids.

S S. Great pectoral muscles.

T T. Lesser pectoral muscles.

U. Mediastinal pleura of right side.

V. Right auricle of the heart.

Plate 1

PLATE 2.

A. Right ventricle of the heart. A a. Pericardium.

B. Pulmonary artery. B b. Pericardium.

C. Ascending aorta. C c. Transverse aorta.

D. Right auricle.

E. Ductus arteriosus in the loop of left vagus nerve, and close to phrenic
nerve of left side.

F. Superior vena cava.

G. Brachio-cephalic vein of left side.

H. Left common carotid artery.

I. Left subclavian vein.

K. Lower end of left internal jugular vein.

L. Right internal jugular vein.

M. Right subclavian vein.

N. Innominate artery—brachio-cephalic.

O. Left subclavian artery crossed by left vagus nerve.

P. Right subclavian artery crossed by right vagus nerve, whose inferior
laryngeal branch loops under the vessel.

Q. Right common carotid artery

R. Trachea.

S. Thyroid body.

T. Brachial plexus of nerves.

U. Upper end of left internal jugular vein.

V V. Clavicles cut across and displaced downwards.

W W. The first ribs.

X X. Fifth ribs cut across.

Y Y. Right and left mammae.

Z. Lower end of sternum.

Plate 2

COMMENTARY ON PLATES 3 & 4.

THE SURGICAL FORM OF THE SUPERFICIAL CERVICAL AND FACIAL REGIONS, AND THE
RELATIVE POSITION OF THE PRINCIPAL BLOOD-VESSELS, NERVES, &c.

When the neck is extended in surgical position, as seen in Plates 3 and 4, its
general outline assumes a quadrilateral shape, approaching to a square. The
sides of this square are formed anteriorly by the line ranging from the mental
symphysis to the top of the sternum, and posteriorly by a line drawn between
the occiput and shoulder. The superior side of this cervical square is drawn by
the horizontal ramus of the lower maxilla, and the inferior side by the
horizontal line of the clavicle. This square space, R 16, 8, 6, Plate 4, is
halved by a diagonal line, drawn by the sterno-cleido-mastoid muscle B, which
cuts the square into two triangles. In the anterior triangle, F 16, 6, Plate 4,
is located the superficial common carotid artery, C, and its branches, D, with
accompanying nerves. In the posterior triangle, 9, 8, 6, Plate 4, is placed the
superficial subclavian artery, A, its branches, L M, and the brachial plexus of
nerves, I. Both these triangles and their contents are completely sheathed by
that thin scarf-like muscle, named platysma myoides, A A, Plate 3, the fibres
of which traverse the neck slantingly in a line, O A, of diagonal direction
opposite to and secant of that of the sterno-mastoid muscle.

When the skin and subcutaneous adipose membrane are removed by careful
dissection from the cervical region, certain structures are exposed, which,
even in the undissected neck, projected on the superficies, and are the
unerring guides to the localities of the blood-vessels and nerves, &c. In
Plate 4, the top of the sternum, 6; the clavicle, 7; the “Pomum Adami,” 1; the
lower maxilla at V; the hyoid bone, Z; the sterno-cleido-mastoid muscle, B; and
the clavicular portion of the trapezius muscle, 8; will readily be felt or
otherwise recognised through the skin, &c. When these several points are
well considered in their relation to one another, they will correctly determine
the relative locality of those structures—the blood-vessels, nerves, &c.,
which mainly concern the surgical operation.

The middle point, between 7, the clavicle, and 6, the sternum, of Plate 4, is
marked by a small triangular space occurring between the clavicular and sternal
divisions of the sterno-cleido-mastoid muscle. This space marks the situation
(very generally) of the bifurcation of the innominate artery into the
subclavian and common carotid arteries of the right side; a penetrating
instrument would, if passed into this space at an inch depth, pierce first the
root of the internal jugular vein, and under it, but somewhat internal, the
root of either of these great arterial vessels, and would wound the right vagus
nerve, as it traverses this region. For some extent after the subclavian and
carotid vessels separate from their main common trunk, they lie concealed
beneath the sterno-mastoid muscle, B, Plate 4, and still deeper beneath the
sternal origins of the sterno-hyoid muscle, 5, and sterno-thyroid muscle, some
of whose fibres are traceable at the intervals. The omo-hyoid muscle and the
deep cervical fascia, as will be presently seen, conceal these vessels also.

The subclavian artery, A, Plate 4, first appears superficial to the above-named
muscles of the cervical region just at the point where, passing from behind the
scalenus muscle, N, Plate 4, which also conceals it, it sinks behind the
clavicle. The exact locality of the artery in this part of its course would be
indicated by a finger’s breadth external to the clavicular attachment of the
sterno-mastoid muscle. The artery passes beneath the clavicle at the middle of
this bone, a point which is indicated in most subjects by that cellular
interval occurring between the clavicular origins of the deltoid and great
pectoral muscles.

The posterior cervical triangle, 9, 8, 7, Plate 4, in which the subclavian
artery is situated, is again subdivided by the muscle omo-hyoid into two lesser
regions, each of which assumes somewhat of a triangular shape. The lower one of
these embraces the vessel, A, and those nerves of the brachial plexus, I, which
are in contact with it. The posterior belly of the omo-hyoid muscle, K, and the
anterior scalenus muscle, N, form the sides and apex of this lesser triangular
space, while the horizontal clavicle forms its base. This region of the
subclavian artery is well defined in the necks of most subjects, especially
when the muscles are put in action. In lean but muscular bodies, it is possible
to feel the projection of the anterior scalenus muscle under the skin, external
to the sterno-mastoid. The form of the omo-hyoid is also to be distinguished in
the like bodies. But in all subjects may be readily recognised that hollow
which occurs above the clavicle, and between the trapezius, 8, and the sterno
cleido-mastoid, 7 B, in the centre of which hollow the artery lies.

The contents of the larger posterior cervical triangle, formed by B, the
sterno-mastoid before; 9, the splenius; and 8, the trapezius behind, and by the
clavicle below, are the following mentioned structures—viz., A, the subclavian
artery, in the third part of its course, as it emerges from behind N, the
scalenus anticus; L, the transversalis colli artery, a branch of the thyroid
axis, which will be found to cross the subclavian vessel at this region; I, the
brachial plexus of nerves, which lie external to and above the vessel; H, the
external jugular vein, which sometimes, in conjunction with a plexus of veins
coming from behind the trapezius muscle, entirely conceals the artery; M, the
posterior scapular artery, a branch of the subclavian, given off from the
vessel after it has passed from behind the scalenus muscle; O, numerous
lymphatic glands; P, superficial descending branches of the cervical plexus of
nerves; and Q, ascending superficial branches of the same plexus. All these
structures, except some of the lymphatic glands, are concealed by the platysma
myoides A, as seen in Plate 3, and beneath this by the cervical fascia, which
latter shall be hereafter more clearly represented.

In somewhat the same mode as the posterior half of the omo-hyoid subdivides the
larger posterior triangle into two of lesser dimensions, the anterior half of
the same muscle divides the anterior triangle into two of smaller capacity.

The great anterior triangle, which is marked as that space inclosed within the
points, 6, the top of the sternum, the mental symphysis and the angle of the
maxilla; and whose sides are marked by the median line of the neck before, the
sterno-mastoid behind, and the ramus of the jaw above, contains C, the common
carotid artery, becoming superficial from beneath the sterno-mastoid muscle,
and dividing into E, the internal carotid, and D, the external carotid. The
anterior jugular vein, 3, also occupies this region below; while some venous
branches, which join the external and internal jugular veins, traverse it in
all directions, and present obstacles to the operator from their meshy
plexiform arrangement yielding, when divided, a profuse haemorrhage.

The precise locality at which the common carotid appears from under the
sterno-mastoid muscle is, in almost all instances, opposite to the thyroid
cartilage. At this place, if an incision, dividing the skin, platysma and some
superficial branches of nerves, be made along the anterior border of the
sterno-mastoid muscle, and this latter be turned a little aside, a process of
cervical fascia, and beneath it the sheath of the carotid artery, will
successionally disclose themselves. In many bodies, however, some degree of
careful search requires to be made prior to the full exposure of the vessel in
its sheath, in consequence of a considerable quantity of adipose tissue, some
lymphatic glands, and many small veins lying in the immediate vicinity of the
carotid artery and internal jugular vein. This latter vessel, though usually
lying completely concealed by the sterno-mastoid muscle, is frequently to be
seen projecting from under its fore part. In emaciated bodies, where the
sterno-mastoid presents wasted proportions, it will, in consequence, leave both
the main blood-vessels uncovered at this locality in the neck.

The common carotid artery ascends the cervical region almost perpendicularly
from opposite the sterno-clavicular articulation to the greater cornu of the os
hyoides. For the greater part of this extent it is covered by the
sterno-mastoid muscle; but as this latter takes an oblique course backwards to
its insertion into the mastoid process, while the main blood-vessel dividing
into branches still ascends in its original direction, so is it that the artery
becomes uncovered by the muscle. Even the root of the internal carotid, E, may
be readily reached at this place, where it lies on the same plane as the
external carotid, but concealed in great part by the internal jugular vein. It
would be possible, while relaxing the sterno-mastoid muscle, to compress either
the common carotid artery or its main branches against the cervical vertebral
column, if pressure were made in a direction backwards and inwards. The facial
artery V, which springs from the external carotid, D, may be compressed against
the horizontal ramus of the lower jaw-bone at the anterior border of the
masseter muscle. The temporal artery, as it ascends over the root of the
zygoma, may be compressed effectually against this bony point.

The external jugular vein, H, Plate 4, as it descends the neck from the angle
of the jaw obliquely backwards over the sterno-mastoid muscle, may be easily
compressed and opened in any part of its course. This vein courses downwards
upon the neck in relation to that branch of the superficial cervical plexus,
named auricularis magnus nerve, Q, Plate 4, G, Plate 3. The nerve is generally
situated behind the vein, to which it lies sometimes in close proximity, and is
liable, therefore, to be accidentally injured in the performance of phlebotomy
upon the external jugular vein. The coats of the external jugular vein, E,
Plate 3, are said to hold connexion with some of the fibres of the
platysma-myoides muscle, A A, Plate 3, and that therefore, if the vessel be
divided transversely, the two orifices will remain patent for a time.

The position of the carotid artery protects the vessel, in some degree, against
the suicidal act, as generally attempted. The depth of the incision necessary
to reach the main blood-vessels from the fore part of the neck is so
considerable that the wound seldom effects more than the opening of some part
of the larynx. The ossified condition of the thyroid and cricoid parts of the
laryngeal apparatus affords a protection to the vessels. The more oblique the
incision happens to be, the greater probability is there that the wound is
comparatively superficial, owing to the circumstance of the instrument having
encountered one or more parts of the hyo-laryngeal range; but woeful chance
sometimes directs the weapon horizontally through that membranous interval
between the thyroid and hyoid pieces, in which case, as also in that where the
laryngeal pieces persist permanently cartilaginous, the resistance to the
cutting instrument is much less.

The anatomical position of the parotid, H, Plate 3, and submaxillary glands, W,
Plate 4, is so important, that their extirpation, while in a state of disease,
will almost unavoidably concern other principal structures. Whether the
diseased parotid gland itself or a lymphatic body lying in connexion with it,
be the subject of operation, it seldom happens that the temporo-maxillary
branch of the external carotid, F, escapes the knife. But an accident, much
more liable to occur, and one which produces a great inconvenience afterwards
to the subject, is that of dividing the portio-dura nerve, S, Plate 4, at its
exit from the stylo-mastoid foramen, the consequence being that almost all the
muscles of facial expression become paralyzed. The masseter, L, Plate 3,
pterygoid, buccinator, 15, Plate 4, and the facial fibres of the platysma
muscles, A O, Plate 3, still, however, preserve their power, as these
structures are innervated from a different source. The orbicularis oculi
muscle, which is principally supplied by the portio-dura nerve, is paralyzed,
though it still retains a partial power of contraction, owing to the anatomical
fact that some terminal twigs of the third or motor pair of nerves of the orbit
branch into this muscle.

The facial artery, V, and the facial vein, U, Plate 4, are in close connexion
with the submaxillary gland. Oftentimes they traverse the substance of it. The
lingual nerve and artery lie in some part of their course immediately beneath
the gland. The former two are generally divided when the gland is excised; the
latter two are liable to be wounded in the same operation.

DESCRIPTION OF PLATES 3 & 4.

PLATE 3.

A A A. Subcutaneous platysma myoides muscle, lying on the face, neck, and upper
part of chest, and covering the structures contained in the two surgical
triangles of the neck.

B. Lip of the thyroid cartilage.

C. Clavicular attachment of the trapezius muscle.

D. Some lymphatic bodies of the post triangle.

E. External jugular vein.

F. Occipital artery, close to which are seen some branches of the occipitalis
minor nerve of the cervical plexus.

G. Auricularis magnus nerve of the superficial cervical plexus.

H. Parotid gland.

I. Temporal artery, with its accompanying vein.

K. Zygoma.

L. Masseter muscle, crossed by the parotid duct, and some fibres of platysma.

M. Facial vein.

N. Buccinator muscle.

O. Facial artery seen through fibres of platysma.

P. Mastoid half of sterno-mastoid muscle.

Q. Locality beneath which the commencements of the subclavian and carotid
arteries lie.

R. Locality of the subclavian artery in the third part of its course.

S. Locality of the common carotid artery at its division into internal and
external carotids.

Plate 3

PLATE 4.

A. Subclavian artery passing beneath the clavicle, where it is crossed by some
blood-vessels and nerves.

B. Sternal attachment of the sterno-mastoid muscle, marking the situation of
the root of common carotid.

C. Common carotid at its point of division, uncovered by sterno-mastoid.

D. External carotid artery branching into lingual, facial, temporal, and
occipital arteries.

E. Internal carotid artery.

F. Temporo-maxillary branch of external carotid artery.

G. Temporal artery and temporal vein, with some ascending temporal branches of
portio-dura nerve.

H. External jugular vein descending from the angle of the jaw, where it is
formed by the union of temporal and maxillary veins.

I. Brachial plexus of nerves in connexion with A, the subclavian artery.

K. Posterior half of the omo-hyoid muscle.

L. Transversalis colli artery.

M. Posterior scapular artery.

N. Scalenus anticus muscle.

O. Lymphatic bodies of the posterior triangle of neck.

P. Superficial descending branches of the cervical plexus of nerves.

Q. Auricularis magnus nerve ascending to join the portio-dura.

R. Occipital artery, accompanied by its nerve, and also by some branches of the
occipitalis minor nerve, a branch of cervical plexus.

S. Portio-dura, or motor division of seventh pair of cerebral nerves.

T. Parotid duct.

U. Facial vein.

V. Facial artery.

W. Submaxillary gland.

X. Digastric muscle.

Y. Lymphatic body.

Z. Hyoid bone.

1. Thyroid cartilage.

2. Superior thyroid artery.

3. Anterior jugular vein.

4. Hyoid half of omo-hyoid muscle.

5. Sterno-hyoid muscle.

6. Top of the sternum.

7. Clavicle.

8. Trapezius muscle.

9. Splenius capitis and colli muscle.

10. Occipital half of occipito-frontalis muscle.

11. Levator auris muscle.

12. Frontal half of occipito-frontalis muscle.

13. Orbicularis oculi muscle.

14. Zygomaticus major muscle.

15. Buccinator muscle.

16. Depressor anguli oris muscle.

(Page 16)

Plate 4

COMMENTARY ON PLATES 5 & 6.

THE SURGICAL FORM OF THE DEEP CERVICAL AND FACIAL REGIONS, AND THE RELATIVE
POSITION OF THE PRINCIPAL BLOODVESSELS AND NERVES, &c.

While the human cervix is still extended in surgical position, its deeper
anatomical relations, viewed as a whole, preserve the quadrilateral form. But
as it is necessary to remove the sterno-cleido-mastoid muscle, in order to
expose the entire range of the greater bloodvessels and nerves, so the diagonal
which that muscle forms, as seen in Plates 3 and 4, disappears, and thus both
the cervical triangles are thrown into one common region. Although, however,
the sterno-mastoid muscle be removed, as seen in Plate 5, still the great
bloodvessels and nerves themselves will be observed to divide the cervical
square diagonally, as they ascend the neck from the sterno-clavicular
articulation to the ear.

The diagonal of every square figure is the junction line of the opposite
triangles which form the square. The cervical square being indicated as that
space which lies within the mastoid process and the top of the sternum—the
symphysis of the lower maxilla and the top of the shoulder, it will be seen, in
Plate 5, that the line which the common carotid and internal jugular vein
occupy in the neck, is the diagonal; and hence the junction line of the two
surgical triangles.

The general course of the common carotid artery and internal jugular vein is,
therefore, obliquely backwards and upwards through the diagonal of the cervical
square, and passing, as it were, from the point of one angle of the square to
that of the opposite—viz., from the sterno-clavicular junction to the
masto-maxillary space; and, taking the anterior triangle of the cervical square
to be that space included within the points marked H 8 A, Plate 5, it will be
seen that the common carotid artery ranges along the posterior side of this
anterior triangle. Again: taking the points 5 Z Y to mark the posterior
triangle of the cervical square, so will it be seen that the internal jugular
vein and the common carotid artery, with the vagus nerve between them, range
the anterior side of this posterior triangle, while the subclavian artery, Q,
passes through the centre of the inferior side of the posterior triangle, that
is, under the middle of the shaft of the clavicle.

The main blood vessels (apparently according to original design) will be found
always to occupy the centre of the animal fabric, and to seek deep-seated
protection under cover of the osseous skeleton. The vertebrae of the neck, like
those of the back and loins, support the principal vessels. Even in the limbs
the large bloodvessels range alongside the protective shafts of the bones. The
skeletal points are therefore the safest guides to the precise localities of
the bloodvessels, and such points are always within the easy recognition of
touch and sight.

Close behind the right sterno-clavicular articulation, but separated from it by
the sternal insertions of the thin ribbon-like muscles named sterno-hyoid and
thyroid, together with the cervical fascia, is situated the brachio-cephalic or
innominate artery, A B, Plates 5 and 6, having at its outer side the internal
jugular division of the brachio-cephalic vein, W K, Plate 5. Between these
vessels lies the vagus nerve, E, Plate 6, N, Plate 5. The common carotid
artery, internal jugular vein, and vagus nerve, hold in respect to each other
the same relationship in the neck, as far upwards as the angle of the jaw.
While we view the general lateral outline of the neck, we find that, in the
same measure as the blood vessels ascend from the thorax to the skull, they
recede from the fore-part of the root of the neck to the angle of the jaw,
whereby a much greater interval occurs between them and the mental symphysis,
or the apex of the thyroid cartilage, than happens between them and the top of
the sternum, as they lie at the root of the neck. This variation as to the
width of the interval between the vessels and fore-part of the neck, in these
two situations, is owing to two causes, 1st, the somewhat oblique course taken
by the vessels from below upwards; 2dly, the projecting development of the
adult lower jaw-bone, and also of the laryngeal apparatus, which latter organ,
as it grows to larger proportions in the male than in the female, will cause
the interval at this place to be much greater in the one than the other. In the
infant, the larynx is of such small size, as scarcely to stand out beyond the
level of the vessels, viewed laterally.

The internal jugular vein is for almost its entire length covered by the
sterno-mastoid muscle, and by that layer of the cervical aponeurosis which lies
between the vessels and the muscle. The two vessels, K C, Plate 5, with the
vagus nerve, are enclosed in a common sheath of cellular membrane, which sends
processes between them so as to isolate the structures in some degree from one
another.

The trunk of the common carotid artery is in close proximity to the vagus
nerve, this latter lying at the vessel’s posterior side. The internal jugular
vein, which sometimes lies upon and covering the carotid, will be found in
general separated from it for a little space. Opposite the os hyoides, the
internal jugular vein lies closer to the common carotid than it does farther
down towards the root of the neck. Opposite to the sterno-clavicular
articulation, the internal jugular vein will be seen separated from the common
carotid for an interval of an inch and more in width, and at this interval
appears the root of the subclavian artery, B, Plates 5 and 6, giving off its
primary branches, viz., the thyroid axis, D, the vertebral and internal mammary
arteries, at the first part of its course.

The length of the common carotid artery varies, of course, according to the
place where the innominate artery below divides, and also according to that
place whereat the common carotid itself divides into internal and external
carotids. In general, the length of the common carotid is considerable, and
ranges between the sterno-clavicular articulation and the level of the os
hyoides; throughout the whole of this length, it seldom or never happens that a
large arterial branch is given off from the vessel, and the operation of
ligaturing the common carotid is therefore much more likely to answer the
results required of that proceeding than can be expected from the ligature of
any part of the subclavian artery which gives off large arterial branches from
every part of its course.

The sympathetic nerve, R, Plate 6, is as close to the carotid artery behind, as
the vagus nerve, N, Plate 5, and is as much endangered in ligaturing this
vessel. The branch of the ninth nerve, E, Plate 5, (descendens noni,) lies upon
the common carotid, itself or its sheath, and is likely to be included in the
ligature oftener than we are aware of.

The trunk of the external carotid, D, Plate 5, is in all cases very short, and
in many bodies can scarcely be said to exist, in consequence of the thyroid,
lingual, facial, temporal, and occipital branches, springing directly from
almost the same point at which the common carotid gives off the internal
carotid artery. The internal carotid is certainly the continuation of the
common arterial trunk, while the vessel named external carotid is only a series
of its branches. If the greater size of the internal carotid artery, compared
to that of the external carotid, be not sufficient to prove that the former is
the proper continuation of the common carotid, a fact may be drawn from
comparative philosophy which will put the question beyond doubt, namely—that as
the common carotid follows the line of the cervical vertebrae, just as the
aorta follows that of the vertebrae of the trunk, so does the internal carotid
follow the line of the cephalic vertebrae. I liken, therefore, those branches
of the so-called external carotid to be, as it were, the visceral arteries of
the face and neck. It would be quite possible to demonstrate this point of
analogy, were this the place for analogical reasoning.

The common carotid, or the internal, may be compressed against the rectus
capitis anticus major muscle, 13, Plate 6, as it lies on the fore-part of the
vertebral column. The internal maxillary artery, 16, Plate 6, and the facial
artery, G, Plate 5, are those vessels which bleed when the lower maxilla is
amputated. In this operation, the temporal artery, 15, Plate 6, will hardly
escape being divided also, it lies in such close proximity to the neck and
condyle of the jaw-bone.

The subclavian artery, B Q, Plate 5, traverses the root of the neck, in an
arched direction from the sterno-clavicular articulation to the middle of the
shaft of the clavicle, beneath which it passes, being destined for the arm. In
general, this vessel rises to a level considerably above the clavicle; and all
that portion of the arching course which it makes at this situation over the
first rib has become the subject of operation. The middle of this arching
subclavian artery is (by as much as the thickness of the scalenus muscle, X,
Plate 5) deeper situated than either extremity of the arch of this vessel, and
deeper also than any part of the common carotid, by the same fact. So many
branches spring from all parts of the arch of the subclavian artery, that the
operation of ligaturing this vessel is less successful than the same operation
exercised on others.

The structures which lie in connexion with the arch of the subclavian also
render the operation of tying the vessel an anxious task. It is crossed and
recrossed at all points by large veins, important nerves, and by its own
principal branches. The vagus nerve, S E, Plate 6, crosses it at B, its root;
external to which place the large internal jugular vein, K, Plate 5, lies upon
it; external to this latter, the scalenus muscle, X, Plate 5, with the phrenic
nerve lying upon the muscle, binds it fixedly to the first rib; more external
still, the common trunk of the external jugular and shoulder veins, U, Plate 5,
lie upon the vessel, and it is in the immediate vicinity of the great brachial
plexus of nerves, P P, which pass down along its humeral border, many branches
of the same plexus sometimes crossing it anteriorly.

The depth at which the middle of the subclavian artery lies may be learned by
the space which those structures, beneath which it passes, necessarily occupy.
The clavicle at its sternal end is round and thick, where it gives attachment
to the sterno-cleido-mastoid muscle. The root of the internal jugular vein,
when injected, will be seen to occupy considerable space behind the clavicle;
and the anterior scalenus muscle is substantial and fleshy. The united spaces
occupied by these structures give the depth of the subclavian artery in the
middle part of its course.

The length of the subclavian artery between its point of branching from the
innominate and that where it gives off its first branches varies in different
bodies, but is seldom so extensive as to assure the operator of the ultimate
success of the process of ligaturing the vessel. Above and below D, Plate 6,
the thyroid axis, come off the vertebral and internal mammary arteries internal
and anterior to the scalenus muscle. External and posterior to the scalenus, a
large vessel, the post scapular, G, Plate 6, R, Plate 5, arises. If an aneurism
attack any part of this subclavian arch, it must be in close connexion with
some one of these branches. If a ligature is to be applied to any part of the
arch, it will seldom happen that it can be placed farther than half an inch
from some of these principal collateral branches.

When the shoulder is depressed, the clavicle follows it, and the subclavian
artery will be more exposed and more easily reached than if the shoulder be
elevated, as this latter movement raises the clavicle over the locality of the
vessel. Dupuytren alludes practically to the different depths of the subclavian
artery in subjects with short necks and high shoulders, and those with long
necks and pendent shoulders. When the clavicle is depressed to the fullest
extent, if then the sterno-cleido-mastoid and scalenus muscles be relaxed by
inclining the head and neck towards the artery, I believe it may be possible to
arrest the flow of blood through the artery by compressing it against the first
rib, and this position will also facilitate the operation of ligaturing the
vessel.

The subclavian vein, W, Plate 5, is removed to some distance from the artery,
Q, Plate 5. The width of the scalenus muscle, X, separates the vein from the
artery. An instance is recorded by Blandin in which the vein passed in company
with the artery under the scalenus muscle.

DESCRIPTION OF PLATES 5 & 6.

PLATE 5.

A. Innominate artery at its point of bifurcation.

B. Subclavian artery crossed by the vagus nerve.

C. Common carotid artery with the vagus nerve at its outer side, and the
descendens noni nerve lying on it.

D. External carotid artery.

E. Internal carotid artery with the descendens noni nerve lying on it.

F. Lingual artery passing under the fibres of the hyo-glossus muscle.

G. Tortuous facial artery.

H. Temporo-maxillary artery.

I. Occipital artery crossing the internal carotid artery and jugular vein.

K. Internal jugular vein crossed by some branches of the cervical plexus, which
join the descendens noni nerve.

L. Spinal accessory nerve, which pierces the sterno-mastoid muscle, to be
distributed to it and the trapezius.

M.Cervical plexus of nerves giving off the phrenic nerve to descend the neck on
the outer side of the internal jugular vein and over the scalenus muscle.

N. Vagus nerve between the carotid artery and internal jugular vein.

O. Ninth or hypoglossal nerve distributed to the muscles of the tongue.

P P. Branches of the brachial plexus of nerves.

Q. Subclavian artery in connexion with the brachial plexus of nerves.

R R. Post scapular artery passing through the brachial plexus.

S. Transversalis humeri artery.

T. Transversalis colli artery.

U. Union of the post scapular and external jugular veins, which enter the
subclavian vein by a common trunk.

V. Post-half of the omo-hyoid muscle.

W. Part of the subclavian vein seen above the clavicle.

X. Scalenus muscle separating the subclavian artery from vein.

Y. Clavicle.

Z. Trapezius muscle.

1. Sternal origin of sterno-mastoid muscle of left side.

2. Clavicular origin of sterno-mastoid muscle of right side turned down.

3. Scalenus posticus muscle.

4. Splenius muscle.

5. Mastoid insertion of sterno-mastoid muscle.

6. Internal maxillary artery passing behind the neck of lower jaw-bone.

7. Parotid duct.

8. Genio-hyoid muscle.

9. Mylo-hyoid muscle, cut and turned aside.

10. Superior thyroid artery.

11. Anterior half of omo-hyoid muscle.

12. Sterno-hyoid muscle, cut.

13. Sterno-thyroid muscle, cut.

Plate 5

PLATE 6.

A. Root of the common carotid artery.

B. Subclavian artery at its origin.

C. Trachea.

D. Thyroid axis of the subclavian artery.

E. Vagus nerve crossing the origin of subclavian artery.

F. Subclavian artery at the third division of its arch.

G. Post scapular branch of the subclavian artery.

H. Transversalis humeri branch of subclavian artery.

I. Transversalis colli branch of subclavian artery.

K. Posterior belly of omo-hyoid muscle, cut.

L. Median nerve branch of brachial plexus.

M. Musculo-spiral branch of same plexus.

N. Anterior scalenus muscle.

O. Cervical plexus giving off the phrenic nerve, which takes tributary branches
from brachial plexus of nerves.

P. Upper part of internal jugular vein.

Q. Upper part of internal carotid artery.

R. Superior cervical ganglion of sympathetic nerve.

S. Vagus nerve lying external to sympathetic nerve, and giving off t its
laryngeal branch.

T. Superior thyroid artery.

U. Lingual artery separated by hyo-glossus muscle from

V. Lingual or ninth cerebral nerve.

W. Sublingual salivary gland.

X. Genio-hyoid muscle.

Y. Mylo-hyoid muscle, cut and turned aside.

Z. Thyroid cartilage.

1. Upper part of sterno-hyoid muscle.

2. Upper part of omo-hyoid muscle.

3. Inferior constrictor of pharynx.

4. Cricoid cartilage.

5. Crico-thyroid muscle.

6. Thyroid body.

7. Inferior thyroid artery of thyroid axis.

8. Sternal tendon of sterno-mastoid muscle, turned down.

9. Clavicular portion of sterno-mastoid muscle, turned down.

10. Clavicle.

11. Trapezius muscle.

12. Scalenus posticus muscle.

13. Rectus capitis anticus major muscle.

14. Stylo-hyoid muscle, turned aside.

15. Temporal artery.

16. Internal maxillary artery.

17. Inferior dental branch of fifth pair of cerebral nerves.

18. Gustatory branch of fifth pair of nerves.

19. External pterygoid muscle.

20. Internal pterygoid muscle.

21. Temporal muscle cut to show the deep temporal branches of fifth pair of
nerves.

22. Zygomatic arch.

23. Buccinator muscle, with buccal nerve and parotid duct.

24. Masseter muscle cut on the lower maxilla.

25. Middle constrictor of pharynx.

Plate 6

COMMENTARY ON PLATES 7 & 8.

THE SURGICAL DISSECTION OF THE SUBCLAVIAN AND CAROTID REGIONS, THE RELATIVE
ANATOMY OF THEIR CONTENTS.

A perfect knowledge of the relative anatomy of any of the surgical regions of
the body must include an acquaintance with the superposition of parts contained
in each region, as well as the plane relationship of organs which hold the same
level in each layer or anatomical stratum. The dissections in Plates 7 and 8
exhibit both these modes of relation. A portion of each of those superficial
layers, which it was necessary to divide, in order to expose a deeper organ,
has been left holding its natural level. Thus the order of superposition taken
by the integument, the fasciae, the muscles, bones, veins, nerves, and
arteries, which occupy both the surgical triangles of the neck, will be readily
recognised in the opposite Plates.

The depth of a bloodvessel or other organ from surface will vary for many
reasons, even though the same parts in the natural order of superposition shall
overlie the whole length of the vessel or organ which we make search for. The
principal of those reasons are:—1st, that the stratified organs themselves vary
in thickness at several places; 2d, that the organ or vessel which we seek will
itself incline to surface from deeper levels occupied elsewhere; 3d, that the
normal undulations of surface will vary the depth of the particular vessels,
&c.; and 4th, that the natural mobility of the superimposed parts will
allow them to change place in some measure, and consequently influence the
relative position of the object of search. On this account it is that the
surgical anatomist chooses to give a fixed position to the subject about to be
operated on, in order to reduce the number of these difficulties as much as
possible.

In Plate 7 will be seen the surgical relationship of parts lying in the
vicinity of the common carotid artery, at the point of its bifurcation into
external and internal carotids. At this locality, the vessel will be found, in
general, subjacent to the following mentioned structures, numbered from the
superficies to its own level—viz., the common integument and subcutaneous
adipose membrane, which will vary in thickness in several individuals; next,
the platysma myoides muscle, F L, which is identified with the superficial
fascia, investing the outer surface of the sterno-mastoid muscle; next, the
deeper layer of the same fascia, R S., which passes beneath the sterno-mastoid
muscle, but over the sheath of the vessels; and next, the sheath of the
vessels, Q, which invests them and isolates them from adjacent structures.
Though the vessel lies deeper than the level of the sterno-mastoid muscle at
this locality, yet it is not covered by the muscle in the same manner, as it is
lower down in the neck. At this place, therefore, though the actual depth of
the artery from surface will be the same, whether it be covered or uncovered by
the sterno-mastoid muscle, still we know that the locality of the vessel
relative to the parts actually superimposed will vary accordingly. This
observation will apply to the situation and relative position of all the other
vessels as well. Other occurrences will vary the relations of the artery in
regard to superjacent structures, though the actual depth of the vessel from
surface may be the same. If the internal jugular vein covers the carotid
artery, as it sometimes does, or if a plexus of veins, gathering from the
fore-part of the neck or face, overlie the vessel, or if a chain of lymphatic
bodies be arranged upon it, as is frequently the case, the knowledge of such
occurrences will guard the judgment against being led into error by the
conventionalities of the descriptive method of anatomists. The normal relative
anatomy of the bloodvessels is taken by anatomists to be the more frequent
disposition of their main trunks and branches, considered per se, and in
connexion with neighbouring parts. But it will be seen by this avowal that
those vessels are liable to many various conditions; and such is the case, in
fact. No anatomist can pronounce with exactness the precise figure of vessels
or other organs while they lie concealed beneath the surface. An approach to
truth is all that the best experience can boast of. The form and relations of
the carotid vessels of Plate 7 may or may not be the same as those concealed
beneath the same region of Plate 8, at the point R.

The motions of the head upon the neck, or of the neck upon the trunk, will
influence the relative position of the vessels A C B, of Plate 7, and therefore
we take a fixed surgical position, in the expectation of finding that the
carotid artery projects from under the anterior border of the upper third of
the sterno-mastoid muscle, opposite the upper border of the thyroid cartilage;
at this situation of the vessels, viz., R, Plate 8, opposite O, the thyroid
projection, is in general to be found the anatomical relation of the vessels as
they appear dissected in Plate 7. Of these vessels, the main trunks are less
liable to anomalous character than the minor branches.

The relative position of the subclavian artery is as liable to be influenced by
the motions of the clavicle on the sternum, as that of the carotid is by the
motions of the lower jaw-bone on the skull, or by the larynx, in its own
motions at the fore-part of the neck. It becomes as necessary, therefore, in
the performance of surgical operations upon the subclavian artery, to fix the
clavicle by depressing it, as in Plate 8, as it is to give fixity to the lower
maxilla and larynx, in the position of Plate 7, when the carotid is the subject
of operation.

The same named structures, but different as to their parts, will be found to
overlie the subclavian artery as are found to conceal the carotid artery. The
skin, the fascia, and platysma muscle, the sterno-cleido-mastoid muscle, the
deep layer of the cervical fascia, &c., cover both vessels. One additional
muscle binds down the subclavian artery, viz., the scalenus anticus. The
omo-hyoid relates to both vessels, the anterior division to the carotid, the
posterior to the subclavian.

The carotid artery lies uncovered by the sterno-mastoid muscle, opposite to the
upper border of the thyroid cartilage, or the hyoid bone; and the subclavian
artery emerges from under cover of a different part of the same muscle,
opposite the middle of the clavicle. These points of relationship to the
skeletal parts can be ascertained by the touch, in both instances, even in the
undissected body. The thyroid point, O, of Plate 8, indicates the line, R N,
which the carotid artery traverses in the same figure, along the anterior
border of the sterno-mastoid muscle, as seen in the dissected region of Plate
7. The mid-point of the clavicle, U, Plate 7, and the top of the sternum in the
same figure, will, while the eye follows the arching line, Z X T V, indicate
with correctness the arching course of the subclavian, such as is represented
in the dissection of that vessel, B, Plate 8.

The subclavian artery has no special sheath, properly so called; but the deep
layer of the cervical fascia, P, Plate 8, which passes under A, the clavicular
portion of the sterno-mastoid muscle, and becomes of considerable thickness and
density, sheaths over the vessel in this region of its course.

A very complex condition of the veins which join the external jugular at this
part of the course of the subclavian artery is now and then to be found
overlying that vessel. If the hemorrhage consequent upon the opening of these
veins, or that of the external jugular, be so profuse as to impede the
operation of ligaturing the subclavian artery, it may in some measure be
arrested by compressing them against the resisting parts adjacent, when the
operator, feeling for D, the scalenus muscle, and the first rib to which it is
attached, cannot fail to alight upon the main artery itself, B, Plate 8.

The middle of the shaft of the clavicle is a much safer guide to the vessel
than are the muscles which contribute to form this posterior triangle of the
neck, in which the subclavian vessel is located. The form or position of the
clavicle in the depressed condition of the shoulder, as seen in Plate 8, is
invariable; whereas that of the trapezius and sterno-mastoid muscles is
inconstant, these muscles being found to stand at unequal intervals from each
other in several bodies. The space between the insertions of both these muscles
is indefinite, and may vary in degrees of width from the whole length of the
clavicle to half an inch; or, as in some instances, leaving no interval
whatever. The position of the omo-hyoid muscle will not be accounted a sure
guide to the locality of the subclavian artery, since, in fact, it varies
considerably as to its relationship with that vessel. The tense cords of the
brachial plexus of nerves, F, Plate 8, which will be found, for the most part,
ranging along the acromial border of the artery, are a much surer guide to the
vessel.

On comparing the subclavian artery, at B, Plate 8, with the common carotid
artery, at A, Plate 7, I believe that the former will be found to exhibit, on
the whole a greater constancy in respect to the following-mentioned
condition—viz., a single main arterial trunk arches over the first rib
to pass beneath the middle of the clavicle, while the carotid artery opposite
the thyroid piece of the larynx is by no means constantly single as a common
carotid trunk. The place of division of the common carotid is not definite,
and, therefore, the precise situation in the upper two-thirds of the neck,
where it may present as a single main vessel, cannot be predicted with
certainty in the undissected body. There is no other main artery of the body
more liable to variation than that known as external carotid. It is subject to
as many changes of character in respect to the place of its branching from the
common carotid, and also in regard to the number of its own branches, as any of
the lesser arteries of the system. It is but as an aggregate of the branches of
that main arterial trunk which ranges from the carotid foramen of the temporal
bone to the aorta; and, as a branch of a larger vessel, it is, therefore,
liable to spring from various places of the principal trunk, just as we find to
be the case with all the other minor branches of the larger arteries. Its name,
external carotid, is as unfittingly applied to it, in comparison with the
vessel from which it springs, as the name external subclavian would be if
applied to the thyroid axis of the larger subclavian vessel. The nomenclature
of surgical anatomy does not, however, court a philosophical inquiry into that
propriety of speech which comparative science demands, nor is it supposed to be
necessary in a practical point of view.

It will, however, sound more euphoneously with reason, and at the same time, I
believe, be found not altogether unrelated to the useful, if, when such
conditions as the “anomalies of form” present themselves, we can advance an
interpretation of the same, in addition to the dry record of them as isolated
facts. Comparative anatomy, which alone can furnish these interpretations, will
therefore prove to be no alien to the practical, while it may lend explanation
to those bizarreries which impede the way of the anthropotomist. All the
anomalies of form, both as regards the vascular, the muscular, and the osseous
systems of the human body, are analyzed by comparison through the animal
series. Numerous cases are on record of the subclavian artery being found
complicated with supernumerary ribs jutting from the 5th, 6th, or 7th cervical
vertebrae. [Footnote] To these I shall add another, in respect of the carotid
arteries—viz., that I have found them complicated with an osseous shaft of
bone, taking place of the stylo-hyoid ligament, a condition which obtains
permanently in the ruminant and other classes of mammals.

[Footnote: I have given an explanation of these facts in my work on Comparative
Osteology and the Archetype Skeleton, to which, and also to Professor Owen’s
work, entitled Homologies of the Vertebrate Skeleton, I refer the reader.]

DESCRIPTION OF PLATES 7 & 8.

PLATE 7.

A. Common carotid at its place of division.

B. External carotid.

C. Internal carotid, with the descending branch of the ninth nerve lying on it.

D. Facial vein entering the internal jugular vein.

E. Sterno-mastoid muscle, covered by

F. Part of the platysma muscle.

G. External jugular vein.

H. Parotid gland, sheathed over by the cervical fascia.

I. Facial vein and artery seen beneath the facial fibres of the platysma.

K. Submaxillary salivary gland.

L. Upper part of the platysma muscle cut.

M. Cervical fascia cut.

N. Sterno-hyoid muscle.

O. Omo-hyoid muscle.

P. Sterno-thyroid muscle.

Q. Fascia proper of the vessels.

R. Layer of the cervical fascia beneath the sterno-mastoid muscle.

S. Portion of the same fascia.

T. External jugular vein injected beneath the skin.

U. Clavicle at the mid-point, where the subclavian artery passes beneath it.

V. Locality of the subclavian artery in the third part of its course.

W. Prominence of the trapezius muscle.

X. Prominence of the clavicular portion of the sterno-cleido-mastoid muscle.

Y. Place indicating the interval between the clavicular and sternal insertions
of sterno-cleido-mastoid muscle.

Z. Projection of the sternal portion of the sterno-cleido-mastoid muscle.

Plate 7

PLATE 8.

A. Clavicular attachment of the sterno-mastoid muscle lying over the internal
jugular vein, &c.

B. Subclavian artery in the third part of its course.

C. Vein formed by the union of external jugular, scapular, and other veins.

D. Scalenus anticus muscle stretching over the artery, and separating it from
the internal jugular vein.

E. Post-half of omo-hyoid muscle.

F. Inner branches of the brachial plexus of nerves.

G. Clavicular portion of trapezius muscle.

H. Transversalis colli artery.

I. Layer of the cervical fascia, which invests the sterno-mastoid and trapezius
muscles.

K. Lymphatic bodies lying between two layers of the cervical fascia.

L. Descending superficial branches of the cervical plexus of nerves.

M. External jugular vein seen under the fascia which invests the sterno-mastoid
muscle.

N. Platysma muscle cut on the body of sterno-mastoid muscle.

O. Projection of the thyroid cartilage.

P. Layer of the cervical fascia lying beneath the clavicular portion of the
sterno-mastoid muscle.

Q. Layer of the cervical fascia continued from the last over the subclavian
artery and brachial plexus of nerves.

Plate 8

COMMENTARY ON PLATES 9 & 10.

THE SURGICAL DISSECTION OF THE STERNO-CLAVICULAR OR TRACHEAL REGION, AND THE
RELATIVE POSITION OF ITS MAIN BLOODVESSELS, NERVES, &c.

The law of symmetry governs the development of all structures which compose the
human body; and all organized beings throughout the animal kingdom are produced
in obedience to this law. The general median line of the human body is
characterized as the point of fusion of the two sides; and all structures or
organs which range this common centre are either symmetrically azygos, or
symmetrically duplex. The azygos organ presents as a symmetrical unity, and the
duplex organ as a symmetrical duality. The surgical anatomist takes a studious
observation of this law of symmetry; and knowing it to be one of general and
almost unexceptional occurrence, he practises according to its manifestation.

The vascular as well as the osseous skeleton displays the law of symmetry; but
while the osseous system offers no exception to this law, the vascular system
offers one which, in a surgical point of view, is of considerable
importance—namely, that behind the right sterno-clavicular articulation, C,
Plate 9, is found the artery, A, named innominate, this being the common trunk
of the right common carotid and subclavian vessels; while on the left side,
behind the left sterno-clavicular junction, Q, Plate 10, the two vessels
(subclavian, B, and carotid, A,) spring separately from the aortic arch. This
fact of asymmetrical arrangement in the arterial trunks at the fore part of the
root of the neck is not, however, of invariable occurrence; on the contrary,
numerous instances are observed where the arteries in question, on the right
side as well as the left, arise separately from the aorta; and thus Nature
reverts to the original condition of perfect symmetry as governing the
development of even the vascular skeleton. And not unfrequently, as if to
invite us to the inquiry whether a separate origin of the four vessels
(subclavian and carotid) from the aorta, or a double innominate condition of
the vessels, were the original form with Nature, we find her also presenting
this latter arrangement of them. An innominate or common aortic origin may
happen for the carotid and subclavian arteries of the left side, as well as the
right. Hence, therefore, while experience may arm the judgment with a general
rule, such generality should not render us unmindful of the possible exception.

When, as in Plate 9, A, the innominate artery rises to a level with C, the
right sterno-clavicular junction, and when at this place it bifurcates, having
on its left side, D, the trachea, and on its right side, B, the root of the
internal jugular vein, together with a, the vagus nerve, the arterial
vessel is said to be of normal character, and holding a normal position
relative to adjacent organs. When, as in Plate 10, A, the common carotid, and
B, the subclavian artery, rise separately from the aortic arch to a level with
Q, the left sterno-clavicular articulation, the vessels having M, the trachea,
to their inner side, and C D, the junction of the internal jugular and
subclavian veins, to their outer side, with b, the left vagus nerve,
between them, then the arterial vessels are accounted as being of normal
character, and as holding a normal relative position. Every exception to this
condition of A, Plate 9, or to that of A B, Plate 10, is said to be abnormal or
peculiar, and merely because the disposition of the vessels, as seen in Plates
9 and 10, is taken to be general or of more frequent occurrence.

Now, though it is not my present purpose to burden this subject of regional
anatomy with any lengthy inquiry into the comparative meaning of the facts, why
a common innominate trunk should occur on the right of the median line, while
separate arterial trunks for the carotid and subclavian arteries should spring
from the aorta on the left of this mid-line, thus making a remarkable exception
to the rule of symmetry which characterizes all the arterial vessels elsewhere,
still I cannot but regard this exceptional fact of asymmetry as in itself
expressing a question by no means foreign to the interests of the practical.

In the abstract or general survey of all those peculiarities of length to which
the innominate artery, A, Plate 9, is subject, I here lay it down as a
proposition, that they occur as graduated phases of the bicleavage of this
innominate trunk from the level of A, to the aortic arch, in which latter
phasis the aorta gives a separate origin to the carotid and subclavian vessels
of the right side as well as the left. On the other hand, I observe that the
peculiarities to the normal separate condition of A and B, the carotid and
subclavian arteries of Plate 10, display, in the relationary aggregate, a
phasial gradation of A and B joining into a common trunk union, in which state
we then find the aorta giving origin to a right and left innominate artery.
Between these two forms of development—viz., that where the four vessels spring
separately from the aortic arch, and that where two innominate or
brachio-cephalic arteries arise from the same—may be read all the sum of
variation to which these vessels are liable. It is true that there are some
states of these vessels which cannot be said to be naturally embraced in the
above generalization; but though I doubt not that these might be encompassed in
a higher generalization; still, for all practical ends, the lesser general rule
is all-sufficient.

In many instances, the innominate artery, A, Plate 9, is of such extraordinary
length, that it rises considerably (for an inch, or even more) above the level
of C, the sternal end of the clavicle. In other cases, the innominate artery
bifurcates soon after it leaves the first part of the aortic arch; and between
these extremes as to length, the vessel varies infinitesimally.

The innominate artery lies closer behind the right sterno-clavicular junction
than the left carotid or subclavian arteries lie in relation to the left
sterno-clavicular articulation; and this difference of depth between the vessel
of the right side and those of the left is mainly owing to the form and
direction of the aortic arch from which they take origin. The aortic arch
ranges, not alone transversely, but also from before backward, and to the left
side of the dorsal spine; and consequently, as the innominate artery, A, Plate
9, springs from the first or fore part of the aorta, while the left carotid and
subclavian arteries arise from the second and deeper part of its arch, the
vessels of both sides rising into the neck perpendicularly from the root in the
thorax, will still, in the cervical region, manifest a considerable difference
as to antero-posterior depth. The depth of the left subclavian artery, B, Plate
10, from cervical surface, is even greater than that of the left common
carotid, A, Plate 10, and this latter, at its root in the aortic arch, is
deeper than the innominate artery. Both common carotids, A A, Plates 9 and 10,
hold nearly the same antero-posterior depth on either side of the trachea, M,
Plate 10, and D, Plate 9. Although the relative depth of the arterial vessels
on both sides of the trachea is different, still they are covered by an equal
number of identical structures, taking the same order of superposition.

On either side of the episternal cervical pit, which, even in the undissected
body of male or female, infant or adult, is always a well-marked surgical
feature, may be readily recognised the converging sternal attachments of the
sterno-mastoid muscles, L G, Plate 10; and midway between these symmetrical
muscular prominences in the neck, but holding a deeper level than them, is
situated that part of the trachea which is generally the subject of the
operation of tracheotomy. The relative anatomy of the trachea, M, Plate 10, D,
Plate 9, at this situation requires therefore to be carefully considered. The
trachea is said to incline rather to the right side of the median line; but
perhaps this observation would be more true to nature if it were accompanied by
the remark, that this seeming inclination to the right side is owing to the
fact, that the innominate artery, A, Plate 9, lies obliquely over its fore
part, near the sternum. However this may be, it certainly will be the safer
step in the operation to regard the median position of the trachea as fixed,
than to encroach upon the locality of the carotid vessels; and to make the
incision longitudinally and exactly through the median line, while the neck is
extended backwards, and the chin made to correspond with the line of incision.
And when the operator takes into consideration the situation of the vessel A,
Plate 9, and A, Plate 10, at this region of the neck, he will at once own to
the necessity of opening the trachea, D, Plate 9, M, Plate 10, at a situation
nearer the larynx than the point marked in the figures. The course taken by the
common carotid arteries is, in respect to the trachea, divergent from below
upwards; and as these vessels will consequently be found to stand wider apart
at the level of K, I, Plate 10, than they do at the level of M, Plate 10, so
the farther upwards from the sternum we choose the point at which to open the
trachea, the less likely are we to endanger the great arterial vessels.

In addition to the fact, that the carotid arteries at an inch above the sternum
lie nearer the median line than they do higher up in the neck, it should always
be remembered, that the trachea itself is situated much deeper at the point M,
Plate 10, D, Plate 9, than it is opposite the points F and K of the same
figures. The laryngo-tracheal line is, in the lateral view of the neck,
downwards and backwards, and therefore it will be found always at a
considerable depth from cervical surface, as it passes behind the first bone of
the sternum, midway between both sterno-mastoid muscles.

In the operation of tracheotomy, the cutting instrument divides the following
named structures as they lie beneath the common integument: If the incision be
made directly upon the median line, the muscles F, sterno-hyoid, and E,
sterno-thyroid, Plate 9, are not necessarily divided, as these structures and
their fellows hold a somewhat lateral position opposite to each other. Beneath
these muscles and above them, thus encasing them, the cervical fascia, f
f, Plate 10, is required to be divided, in order to expose the trachea.
Beneath f f the cervical fascia, will next be felt the rounded bilobed
mass of the thyroid body, lying on the forepart of the trachea; above the
thyroid body, the cricoid and some tracheal cartilaginous rings will be felt;
and since the thyroid body varies much as to bulk in several individuals of the
same and different sexes, as also from a consideration that its substance is
traversed by large arterial and venous vessels, it will be therefore preferable
to open the trachea above it, than through it or below it.

On the forepart of the tracheal median line, either superficial to, or deeper
than, the cervical fascia, the tracheotomist occasionally meets with a chain of
lymphatic glands or a plexus of veins, which latter, when divided, will trammel
the operation by the copious haemorrhage which all veins at this region of the
neck are prone to supply, owing to their direct communication with the main
venous trunks of the heart; and not unfrequently the inferior thyroid artery
overlies the trachea at the point D, Plate 9, when this thyroid vessel arises
directly from the arch of the aorta, between the roots of the innominate and
left common carotid, or when it springs from the innominate itself. The
inferior thyroid vein, sometimes single and sometimes double, overlies the
trachea at the point D, Plate 9, when this vein opens into the left innominate
venous trunk, as this latter crosses over the root of the main arteries
springing from the aorta.

Laryngotomy is, anatomically considered, a far less dangerous operation than
tracheotomy, for the above-named reasons; and the former should always be
preferred when particular circumstances do not render the latter operation
absolutely necessary. In addition to the fact, that the carotid arteries lie
farther apart from each other and from the median place—viz., the crico-thyroid
interval, which is the seat of laryngotomy—than they do lower down on either
side of the trachea, it should also be noticed that the tracheal tube being
more moveable than the larynx, is hence more liable to swerve from the cutting
instrument, and implicate the vessels. Tracheotomy on the infant is a far more
anxious proceeding than the same operation performed on the adult; because the
trachea in the infant’s body lies more closely within the embrace of the
carotid arteries, is less in diameter, shorter, and more mobile than in the
adult body.

The episternal or interclavicular region is a locality traversed by so many
vitally important structures gathered together in a very limited space, that
all operations which concern this region require more steady caution and
anatomical knowledge than most surgeons are bold enough to test their
possession of. The reader will (on comparing Plates 9 and 10) be enabled to
take account of those structures which it is necessary to divide in the
operation required for ligaturing the innominate artery, A, Plate 9, or either
of those main arterial vessels (the right common carotid and subclavian) which
spring from it; and he will also observe that, although the same number and
kind of structures overlie the carotid and subclavian vessels, A B, of the left
side, Plate 10, still, that these vessels themselves, in consequence of their
separate condition, will materially influence the like operation in respect to
them. An aneurism occurring in the first part of the course of the right
subclavian artery, at the locality a, Plate 9, will lie so close to the
origin of the right common carotid as to require a ligature to be passed around
the innominate common trunk, thus cutting off the flow of blood from both
vessels; whereas an aneurism implicating either the left common carotid at the
point A, or the left subclavian artery at the point B, does not, of course,
require that both vessels should be included in the same ligature. There seems
to be, therefore, a greater probability of effectually treating an aneurism of
the left brachio-cephalic vessels by ligature than attaches to those of the
right side; for if space between collateral branches, and also a lesser caliber
of arterial trunk, be advantages, allowing the ligature to hold more firmly,
then the vessels of the left side of the root of the neck manifest these
advantages more frequently than those of the right, which spring from a common
trunk. Whenever, therefore, the “peculiarity” of a separate aortic origin of
the right carotid and subclavian arteries occurs, it is to be regarded more as
a happy advantage than otherwise.

DESCRIPTION OF PLATES 9 & 10.

PLATE 9.

A. Innominate artery, at its point of bifurcation.

B. Right internal jugular vein, joining the subclavian vein.

C. Sternal end of the right clavicle.

D. Trachea.

E. Right sterno-thyroid muscle, cut.

F. Right sterno-hyoid muscle, cut.

G. Right sterno-mastoid muscle, cut.

a. Right vagus nerve, crossing the subclavian artery.

b. Anterior jugular vein, piercing the cervical fascia to join the
subclavian vein.

Plate 9

PLATE 10.

A. Common carotid artery of left side.

B. Left subclavian artery, having b, the vagus nerve, between it and A.

C. Lower end of left internal jugular vein, joining—

D. Left subclavian vein, which lies anterior to d, the scalenus anticus
muscle.

E. Anterior jugular vein, coursing beneath sterno-mastoid muscle and over the
fascia.

F. Deep cervical fascia, enclosing in its layers f f f, the several
muscles.

G. Left sterno-mastoid muscle, cut across, and separated from g g, its
sternal and clavicular attachments.

H. Left sterno-hyoid muscle, cut.

I. Left sterno-thyroid muscle, cut.

K. Right sterno-hyoid muscle.

L. Right sterno-mastoid muscle.

M. Trachea.

N. Projection of the thyroid cartilage.

O. Place of division of common carotid.

P. Place where the subclavian artery passes beneath the clavicle.

Q. Sternal end of the left clavicle.

Plate 10

COMMENTARY ON PLATES 11 & 12.

THE SURGICAL DISSECTION OF THE AXILLARY AND BRACHIAL REGIONS, DISPLAYING THE
RELATIVE ORDER OF THEIR CONTAINED PARTS.

All surgical regions have only artificial boundaries; and these, as might be
expected, do not express the same meaning while viewed from more points than
one. These very boundaries themselves, being moveable parts, must accordingly
influence the relative position of the structures which they bound, and thus
either include within or exclude from the particular region those structures
wholly or in part which are said to be proper to it. Of this kind of
conventional surgical boundary the moveable clavicle is an example; and the
bloodvessels which it overarches manifest consequently neither termination nor
origin except artificially from the fixed position which the bone, R, assumes,
as in Plate 11, or c*, Plate 12. In this position of the arm in relation
to the trunk, the subclavian artery, B, terminates at the point where, properly
speaking, it first takes its name; and from this point to the posterior fold of
the axilla formed by the latissimus dorsi muscle, O, Plate 11, N, Plate 12, and
the anterior fold formed by the great pectoral muscle, K, Plate 11, I, Plate
12, the continuation of the subclavian artery is named axillary. From the
posterior fold of the axilla, O P, Plate 11, to the bend of the elbow, the same
main vessels take the name of brachial.

When the axillary space is cut into from the forepart through the great
pectoral muscle, H K, Plate 11, and beneath this through the lesser pectoral
muscle, L I, together with the fascial processes which invest these muscles
anteriorly and posteriorly, the main bloodvessels and nerves which traverse
this space are displayed, holding in general that relative position which they
exhibit in Plate 11. These vessels, with their accompanying nerves, will be
seen continued from those of the neck; and thus may be attained in one view a
comparative estimate of the cervical and axillary regions, together with their
line of union beneath the clavicle, c*, Plate 12, R, Plate 11, which
serves to divide them surgically.

In the neck, the subclavian artery, B, Plate 11, is seen to be separated from
the subclavian vein, A, by the breadth of the anterior scalenus muscle, D, as
the vessels arch over the first rib, F. In this region of the course of the
vessels, the brachial plexus of nerves, C, ranges along the outer border of the
artery, B, and is separated by the artery from the vein, A, as all three
structures pass beneath the clavicle, R, and the subclavius muscle, E. From
this latter point the vessels and nerves take the name axillary, and in this
axillary region the relative position of the nerves and vessels to each other
and to the adjacent organs is somewhat changed. For now in the axillary region
the vein, a, is in direct contact with the artery, b, on the
forepart and somewhat to the inner side of which the vein lies; while the
nerves, D, d, Plate 12, embrace the artery in a mesh or plexus of
chords, from which it is often difficult to extricate it, for the purpose of
ligaturing, in the dead subject, much less the living. The axillary plexus of
nerves well merits the name, for I have not found it in any two bodies assuming
a similar order or arrangement. Perhaps the order in which branches spring from
the brachial plexus that is most constantly met with is the one represented at
D, Plate 12, where we find, on the outer border of B, the axillary artery, a
nervous chord, d, giving off a thoracic branch to pass behind H, the
lesser pectoral muscle, while the main chord itself, d, soon divides
into two branches, one the musculo-cutaneous, e, which pierces G, the
coraco-brachialis muscle, and the other which forms one of the roots of the
median nerve, h. Following that order of the nerves as they are shown in
Plate 12, they may be enumerated from without inwards as follows:—the external
or musculo-cutaneous, e; the two roots of the median, h; the
ulnar, f; the musculo-spiral, g; the circumflex, i; close
to which are seen the origins of the internal cutaneous, the nerve of Wrisberg,
some thoracic branches, and posteriorly the subscapular nerve not seen in this
view of the parts.

The branches which come off from the axillary artery are very variable both as
to number and place of origin, but in general will be found certain branches
which answer to the names thoracic, subscapular, and circumflex. These vessels,
together with numerous smaller arteries, appear to be confined to no fixed
point of origin, and on this account the place of election for passing a
ligature around the main axillary artery sufficiently removed from collateral
branches must be always doubtful. The subscapular artery, Q, Plate 12, is
perhaps of all the other branches that one which manifests the most permanent
character; its point of origin being in general opposite the interval between
the latissimus and sub-scapular muscles, but I have seen it arise from all
parts of the axillary main trunk. If it be required to give, in a history of
the arteries, a full account of all the deviations from the so-called normal
type to which these lesser branches here and elsewhere are subject, such
account can scarcely be said to be called for in this place.

The form of the axillary space is conical, while the arm is abducted from the
side, and while the osseous and muscular structures remain entire. The apex of
the cone is formed at the root of the neck beneath the clavicle, R, Plate 11,
and the subclavious muscle, E, and between the coracoid process, L*, of the
scapula and the serratus magnus muscle, as this lies upon the thoracic side; at
this apex the subclavian vessels, A B, enter the axillary space. The base of
the cone is below, looking towards the arm, and is formed in front by the
pectoralis major, K H, and behind by the latissimus dorsi, O, and teres
muscles, P, together with a dense thick fascia; at this base the axillary
vessels, a b, pass out to the arm, and become the brachial vessels,
a*b*. The anterior side of the cone is formed by the great pectoral
muscle, H K, Plate 11, and the lesser pectoral, L I. The inner side is formed
by the serratus magnus muscle, M, Plate 12, on the side of the thorax; the
external side is formed by the scapular and humeral insertion of the
subscapular muscle, the humerus and coraco-brachialis muscle; and the posterior
side is formed by the latissimus dorsi, the teres and body of the subscapular
muscle.

In this axillary region is contained a complicated mass of bloodvessels,
nerves, and lymphatic glands, surrounded by a large quantity of loose cellular
membrane and adipose tissue. All the arterial branches here found are given off
from the axillary artery; and the numerous veins which accompany these branches
enter the axillary vein. Nerves from other sources besides those of the
axillary plexus traverse the axillary space; such nerves, for example, as those
named intercosto-humeral, seen lying on the latissimus tendon, O, Plate 11. The
vein named cephalic, S, enters the axillary space at that cellular interval
occurring between the clavicular origin of the deltoid muscle, G, and the
humeral attachment of the pectoralis major, H, which interval marks the place
of incision for tying the axillary artery.

The general course of the main vessels through the axillary space would be
indicated with sufficient accuracy by a line drawn from the middle of the
clavicle, R R, Plate 11, to the inner border of the biceps muscle, N. In this
direction of the axillary vessels, the coracoid process, L*, from which arises
the tendon of the pectoralis minor muscle, L, is to be taken as a sure guide to
the place of the artery, b, which passes, in general, close to the inner
side of this bony process. Even in the undissected body the coracoid process
may be felt as a fixed resisting point at that cellular interval between the
clavicular attachments of the deltoid and great pectoral muscles. Whatever
necessity shall require a ligature to be placed around the axillary in
preference to the subclavian artery, must, of course, be determined by the
particular case; but certain it is that the main artery, at the place B, a
little above the clavicle, will always be found freer and more isolated from
its accompanying nerves and vein, and also more easily reached, owing to its
comparatively superficial situation, than when this vessel has become axillary.
The incision required to be made, in order to reach the axillary artery,
b, from the forepart, through the skin, both pectoral muscles, and
different layers of fasciae, must be very deep, especially in muscular,
well-conditioned bodies; and even when the level of the vessel is gained, it
will be found much complicated by its own branches, some of which overlie it,
as also by the plexus of nerves, D, Plate 12, which embraces it on all sides,
while the large axillary vein, a, Plate 11, nearly conceals it in front.
This vein in Plate 11 is drawn somewhat apart from the artery.

Sometimes the axillary artery is double, in consequence of its high division
into brachial branches. But as this peculiarity of premature division never
takes place so high up as where the vessel, B, Plate 11, overarches the first
rib, F, this circumstance should also have some weight with the operator.

When we view the relative position of the subclavian vessels, A B, Plate 11, to
the clavicle, R, we can readily understand why a fracture of the middle of this
bone through that arch which it forms over the vessels, should interfere with
the free circulation of the blood which these vessels supply to the arm. When
the clavicle is severed at its middle, the natural arch which the bone forms
over the vessels and nerves is lost, and the free moving broken ends of the
bone will be acted on in opposing directions by the various muscles attached to
its sternal and scapular extremities. The outer fragment follows more freely
than the inner piece the action of the muscles; but, most of all, the weight of
the unsupported shoulder and arm causes the displacement to which the outer
fragment is liable. The subclavius muscle, E, like the pronator quadratus
muscle of the forearm, serves rather to further the displacement of the broken
ends of the bone than to hold them in situ.

If the head of the humerus be dislocated forwards beneath L, Plate 11, the
coracoid attachment of the pectoralis minor muscle, it must press out of their
proper place and put tensely upon the stretch the axillary vessels and plexus
of nerves. So large and resistent a body as the head of the humerus displaced
forwards, and taking the natural position of these vessels and nerves, will
accordingly be attended with other symptoms—such as obstructed circulation and
pain or partial paralysis, besides those physical signs by which we distinguish
the presence of it as a new body in its abnormal situation.

When the main vessels and nerves pass from the axillary space to the inner side
of the arm, they become comparatively superficial in this latter situation. The
inner border of the biceps muscle is taken as a guide to the place of the
brachial artery for the whole extent of its course in the arm. In plate 11, the
artery, b*, is seen in company with the median nerve, which lies on its
fore part, and with the veins called comites winding round it and
passing with it and the nerve beneath the fascia which encases in a fold of
itself all three structures in a common sheath. Though the axillary vein is in
close contact with the axillary artery and nerves, yet the basilic vein,
d*, the most considerable of those vessels which form the axillary vein,
is separated from the brachial artery by the fascia. The basilic vein, however,
overlies the brachial artery to its inner side, and is most commonly attended
by the internal cutaneous nerve, seen lying upon it in Plate 11, as also by
that other cutaneous branch of the brachial plexus, named the nerve of
Wrisberg. If a longitudinal incision in the course of the brachial artery be
made (avoiding the basilic vein) through the integument down to the fascia of
the arm, and the latter structure be slit open on the director, the artery will
be exposed, having the median nerve lying on its outer side in the upper third
of the arm, and passing to its inner side towards the bend of the elbow, as at
b*, Plate 12. The superior and inferior profunda arteries, seen
springing above and below the point b, Plate 12, are those vessels of
most importance which are given off from the brachial artery, but the situation
of their origin is very various. The ulnar nerve, f, lies close to the
inner side of the main arterial trunk, as this latter leaves the axilla, but
from this place to the inner condyle, Q, behind which the ulnar nerve passes
into the forearm, the nerve and artery become gradually more and more separated
from each other in their descent. The musculo-spiral nerve, g, winds
under the brachial artery at the middle of the arm, but as this nerve passes
deep between the short and long heads of the triceps muscle, P, and behind the
humerus to gain the outer aspect of the limb, a little care will suffice for
avoiding the inclusion of it in the ligature.

The brachial artery may be so effectually compressed by the fingers on the
tourniquet, against the humerus in any part of its course through the arm, as
to stop pulsation at the wrist.

The tourniquet is a less manageable and not more certain compressor of the
arterial trunk than is the hand of an intelligent assistant. At every region of
the course of an artery where the tourniquet is applicable, a sufficient
compression by the hand is also attainable with greater ease to the patient;
and the hand may compress the vessel at certain regions where the tourniquet
would be of little or no use, or attended with inconvenience, as in the
locality of the subclavian artery, passing over the first rib, or the femoral
artery, passing over the pubic bone, or the carotid vessels in the
neighbourhood of the trachea, as they lie on the fore part of the cervical
spinal column.

DESCRIPTION OF PLATES 11 & 12.

PLATE 11.

A. Subclavian vein, crossed by a branch of the brachial plexus given to the
subclavius muscle; a, the axillary vein; a *, the basilic vein,
having the internal cutaneous nerve lying on it.

B. Subclavian artery, lying on F, the first rib; b, the axillary artery;
b *, the brachial artery, accompanied by the median nerve and venae
comites.

C. Brachial plexus of nerves; c*, the median nerve.

D. Anterior scalenus muscle.

E. Subclavius muscle.

F F. First rib.

G. Clavicular attachment of the deltoid muscle.

H. Humeral attachment of the great pectoral muscle.

I. A layer of fascia, encasing the lesser pectoral muscle.

K. Thoracic half of the great pectoral muscle.

L. Coracoid attachment of the lesser pectoral muscle.

L*. Coracoid process of the scapula.

M. Coraco-brachialis muscle.

N. Biceps muscle.

O. Tendon of the latissimus dorsi muscle, crossed by the intercosto-humeral
nerves.

P. Teres major muscle, on which and O is seen lying Wrisberg’s nerve.

Q. Brachial fascia, investing the triceps muscle. .

R R. Scapular and sternal ends of the clavicle.

S. Cephalic vein, coursing between the deltoid and pectoral muscles, to enter
at their cellular interval into the axillary vein beneath E, the subclavius
muscle.

Plate 11

PLATE 12.

A. Axillary vein, cut and tied; a, the basilic vein, cut.

B. Axillary artery; b, brachial artery, in the upper part of its course,
having h, the median nerve, lying rather to its outer side; b*,
the artery in the lower part of its course, with the median nerve to its inner
side.

C. Subclavius muscle.

C*. Clavicle.

D. Axillary plexus of nerves, of which d is a branch on the coracoid
border of the axillary artery; e, the musculo-cutaneous nerve, piercing
the coraco-brachialis muscle; f, the ulnar nerve; g,
musculo-spiral nerve; h, the median nerve; i, the circumflex
nerve.

E. Humeral part of the great pectoral muscle.

F. Biceps muscle.

G. Coraco-brachialis muscle.

H. Thoracic half of the lesser pectoral muscle.

I. Thoracic half of the greater pectoral muscle.

K. Coracoid attachment of the lesser pectoral muscle.

K*. Coracoid process of the scapula.

L. Lymphatic glands.

M. Serratus magnus muscle.

N. Latissimus dorsi muscle.

O. Teres major muscle.

P. Long head of triceps muscle.

Q. Inner condyle of humerus.

Plate 12

COMMENTARY ON PLATES 13 & 14.

THE SURGICAL FORM OF THE MALE AND FEMALE AXILLAE COMPARED.

Certain characteristic features mark those differences which are to be found in
all corresponding regions of both sexes. Though the male and female bodies, in
all their regions, are anatomically homologous or similar at basis, yet the
constituent and corresponding organs of each are gently diversified by the plus
or minus condition, the more or the less, which the development of certain
organs exhibits; and this diversity, viewed in the aggregate, constitutes the
sexual difference. That diversity which defines the sexual character of beings
of the same species, is but a link in that extended chain of differential
gradation which marks its progress through the whole animal kingdom. The female
breast is a plus glandular organ, situated, pendent, in that very position
where, in a male body, the unevolved mamma is still rudimentarily manifested.

The male and female axillae contain the same number and species of organs; and
the difference by which the external configuration of both are marked mainly
arises from the presence of the enlarged mammary gland, which, in the female,
Plate 14, masks the natural outline of the pectoral muscle, E, whose axillary
border is overhung by the gland; and thus this region derives its peculiarity
of form, contrasted with that of the male subject.

When the dissected axilla is viewed from below, the arm being raised, and
extended from the side, its contained parts, laid deeply in their conical
recess, are sufficiently exposed, at the same time that the proper boundaries
of the axillary cavity are maintained. In this point of view from which the
axillary vessels are now seen, their relative position, in respect to the
thorax and the arm, are best displayed. The thickness of that fleshy anterior
boundary formed by both pectoral muscles, E F, Plate 13, will be marked as
considerable; and the depth at which these muscles conceal the vessels, A B, in
the front aspect of the thoracico-humeral interval, will prepare the surgeon
for the difficulties he is to encounter when proceeding to ligature the
axillary artery at the incision made through the anterior or pectoral wall of
this axillary space.

The bloodvessels of the axilla follow the motions of the arm; and according to
the position assumed by the arm, these vessels describe various curves, and lie
more or less removed from the side of the thorax. While the arm hangs close to
the side, the axillary space does not (properly speaking) exist; and in this
position, the axillary vessels and nerves make a general curve from the
clavicle at the point K, Plate 14, to the inner side of the arm, the concavity
of the curve being turned towards the thoracic side. But when the arm is
abducted from the side, and elevated, the vessels which are destined to supply
the limb follow it, and in this position they take, in reality, a serpentine
course; the first curve of which is described, in reference to the thorax, from
the point K to the head of the humerus; and the next is that bend which the
head of the humerus, projecting into the axilla in the elevated position of the
member, forces them to make around itself in their passage to the inner side of
the arm. The vessels may be readily compressed against the upper third of the
humerus by the finger, passed into the axilla, and still more effectually if
the arm be raised, as this motion will rotate the tuberous head of the humerus
downwards against them.

The vessels and nerves of the axilla are bound together by a fibrous sheath
derived from the membrane called costo-coracoid; and the base or humeral outlet
of this axillary space, described by the muscles C, K, E, G, Plate 13, is
closed by a part of the fascial membrane, g, extended across from the
pectoral muscle, E, to the latissimus dorsi tendon, K. In the natural position
of the vessels at that region of their course represented in the Plates, the
vein A overlies the artery B, and also conceals most of the principal nerves.
In order to show some of these nerves, in contact with the artery itself, the
axillary vein is drawn a little apart from them.

The axillary space gives lodgment to numerous lymphatic glands, which are
either directly suspended from the main artery, or from its principal branches,
by smaller branches, destined to supply them. These glands are more numerous in
the female axilla, Plate 14, than in the male, Plate 13, and while they seem to
be, as it were, indiscriminately scattered here and there through this region,
we observe the greater number of them to be gathered together along the
axillary side of the great pectoral muscle; at which situation, h, in
the diseased condition of the female breast, they will be felt to form hard,
nodulated masses, which frequently extend as far up through the axillary space
as the root of the neck, involving the glands of this latter region also in the
disease.

The contractile motions of the pectoral muscle, E, of the male body, Plate 13,
are during life readily distinguishable; and that boundary which it furnishes
to the axillary region is well defined; but in the female form, Plate 14, the
general contour of the muscle E, while in motion, is concealed by the
hemispherical mammary gland, F, which, surrounded by its proper capsule, lies
loosely pendent from the fore part of the muscle, to which, in the healthy
state of the organ, it is connected only by free-moving bonds of lax cellular
membrane. The motions of the shoulder upon the trunk do not influence the
position of the female mammary gland, for the pectoral muscle acts freely
beneath it; but when a scirrhus or other malignant growth involves the mammary
organ, and this latter contracts, by the morbid mass, a close adhesion to the
muscle, then these motions are performed with pain and difficulty.

When it is required to excise the diseased female breast, (supposing the
disease to be confined to the structure of the gland itself,) the operation may
be performed confidently and without difficulty, in so far as the seat of
operation does not involve the immediate presence of any important nerves or
bloodvessels. But when the disease has extended to the axillary glands, the
extirpation of these (as they lie in such close proximity to the great axillary
vessels and their principal branches) requires cautious dissection. It has more
than once happened to eminent surgeons, that in searching for and dissecting
out these diseased axillary glands, H, h, Plate 14, the main artery has
been wounded.

As the coracoid process points to the situation of the artery in the axilla, so
the coraco-brachialis muscle, C, marks the exact locality of the vessel as it
emerges from this region; the artery ranges along the inner margin of both the
process and the muscle, which latter, in fleshy bodies, sometimes overhangs and
conceals it. When the vessel has passed the insertion of the coraco-brachialis,
it becomes situated at the inner side of the biceps, which also partly overlaps
it, as it now lies on the forepart of the brachialis anticus. As the general
course of the artery, from where it leaves the axilla to the bend of the elbow,
is one of winding from the inner side to the forepart of the limb, so should
compression of the vessel, when necessary, be directed in reference to the bone
accordingly—viz., in the upper or axillary region of the arm, from within
outwards, and in the lower part of the arm, from before backwards.

All incised, lacerated, or contused wounds of the arm and shoulder, happening
by pike, bayonet, sabre, bullet, mace, or arrow, on the outer aspect of the
limb, are (provided the weapon has not broken the bones) less likely to
implicate the great arteries, veins, and nerves. These instruments encountering
the inner or axillary aspect of the member, will of course be more likely to
involve the vessels and nerves in the wound. In severe compound fractures of
the humerus occurring from force applied at the external side of the limb, the
brachial vessels and nerves have been occasionally lacerated by the sharp
jagged ends of the broken bone,—a circumstance which calls for immediate
amputation of the member.

The axilla becomes very frequently the seat of morbid growths, which, when they
happen to be situated beneath the dense axillary fascia, and have attained to a
large size, will press upon the vessels and nerves of this region, and cause
very great inconvenience. Adipose and other kind of tumours occurring in the
axilla beneath the fascia, and in close contact with the main vessels, have
been known to obstruct these vessels to such a degree, as to require the
collateral or anastomatic circulation to be set up for the support; of the
limb. When abscesses take place in the axilla, beneath the fascia, it is this
structure which will prevent the matter from pointing; and it is required,
therefore, to lay this fascia freely open by a timely incision. The
accompanying Plates will indicate the proper direction in which such incision
should be made, so as to avoid the vessels A, B. When the limb is abducted from
the side, the main vessels and nerves take their position parallel with the
axis of the arm. The axillary vessels and nerves being thus liable to pressure
from the presence of large tumours happening in their neighbourhood, will
suggest to the practitioner the necessity for fashioning of a proper form and
size all apparatus, which in fracture or dislocation of the shoulder-bones
shall be required to bear forcibly against the axillary region. While we know
that the locality of the main vessels and nerves is that very situation upon
which a pad or fulcrum presses, when placed in the axilla for securing the
reduction of fractures of the clavicle, the neck of the humerus, or scapula, so
should this member of the fracture apparatus be adapted, as well to obviate
this pressure upon these structures, as to give the needful support to the limb
in reference to the clavicle, &c. The habitual use, for weeks or more, of a
hard, resisting fulcrum in the axilla, must act in some degree like the pad of
a tourniquet, arresting the flow of a vigorous circulation, which is so
essential to the speedy union of all lesions of bones. And it should never be
lost sight of, that all grievously coercive apparatus, which incommode the
suffering patient, under treatment, are those very instruments which impede the
curative process of Nature herself.

The anatomical mechanism of the human body, considered as a whole, or divisible
into regions, forms a study so closely bearing upon practice, that the surgeon,
if he be not also a mechanician, and fully capable of making his anatomical
knowledge suit with the common principles of mechanics, while devising methods
for furthering the efforts, of Nature curatively, may be said to have studied
anatomy to little or no purpose. The shoulder apparatus, when studied through
the principle of mechanics, derives an interest of practical import which all
the laboured description of the schools could never supply to it, except when
illustrating this principle.

The disposal of the muscular around the osseous elements of the shoulder
apparatus, forms a study for the surgeon as well in the abnormal condition of
these parts, as in their normal arrangement; for in practice he discovers that
that very mechanical principle upon which both orders of structures (the
osseous and muscular) are grouped together for normal articular action,
becomes, when the parts are deranged by fracture or, other accident, the chief
cause whereby rearrangement is prevented, and the process of reunion
obstructed. When a fracture happens in the shaft of the humerus, above or below
the insertions of the pectoral and latissimus dorsi muscles, these are the very
agents which when the bone possessed its integrity rendered it functionally
fitting, and which, now that the bone is severed, produce the displacement of
the lower fragment from the upper one. To counteract this source of
derangement, the surgeon becomes the mechanician, and now, for the first time,
he recognises the necessity of the study of topographical anatomy.

When a bone is fractured, or dislocated to a false position and retained there
by the muscular force, the surgeon counteracts this force upon mechanical
principle; but while he puts this principle in operation, he also acknowledges
to the paramount necessity of ministering to the ease of Nature as much as
shall be consistent with the effectual use of the remedial agent; and in the
present state of knowledge, it is owned, that that apparatus is most efficient
which simply serves both objects, the one no less than the other. And, assuming
this to be the principle which should always guide us in our treatment of
fractures and dislocations, I shall not hesitate to say, that the pad acting as
a fulcrum in the axilla, or the perineal band bearing as a counterextending
force upon the groin (the suffering body of the patient being, in both
instances, subjected for weeks together to the grievous pressure and irritation
of these members of the apparatus), do not serve both objects, and only one
incompletely; I say incompletely, for out of every six fractures of either
clavicle or thigh-bone, I believe that, as the result of our treatment by the
present forms of mechanical contrivances, there would not be found three cases
of coaptation of the broken ends of the bone so complete as to do credit to the
surgeon. The most pliant and portable of all forms of apparatus which
constitute the hospital armamentaria, is the judgment; and this cannot give its
approval to any plan of instrument which takes effect only at the expense of
the patient.

DESCRIPTION OF PLATES 13 & 14.

PLATE 13.

A. Axillary vein, drawn apart from the artery, to show the nerves lying between
both vessels. On the bicipital border of the vein is seen the internal
cutaneous nerve; on the tricipital border is the nerve of Wrisberg,
communicating with some of the intercosto-humeral nerves; a, the common
trunk of the venae comites, entering the axillary vein.

B. Axillary artery, crossed by one root of the median nerve; b, basilic
vein, forming, with a, the axillary vein, A.

C. Coraco-brachialis muscle.

D. Coracoid head of the biceps muscle.

E. Pectoralis major muscle.

F. Pectoralis minor muscle.

G. Serratus magnus muscle, covered by g, the axillary fascia, and
perforated, at regular intervals, by the nervous branches called
intercosto-humeral.

H. Conglobate gland, crossed by the nerve called “external respiratory” of
Bell, distributed to the serratus magnus muscle. This nerve descends from the
cervical plexus.

I. Subscapular artery.

K. Tendon of latissimus dorsi muscle.

L. Teres major muscle.

Plate 13

PLATE 14.

A. Axillary vein.

B. Axillary artery.

C. Coraco-brachialis muscle.

D. Short head of the biceps muscle.

E. Pectoralis major muscle.

F. Mammary gland, seen in section.

G. Serratus magnus muscle.

H. Lymphatic gland; h h, other glands of the lymphatic class.

I. Subscapular artery, crossed by the intercosto-humeral nerves and descending
parallel to the external respiratory nerve. Beneath the artery is seen a
subscapular branch of the brachial plexus, given to the latissimus dorsi
muscle.

K. Locality of the subclavian artery.

L. Locality of the brachial artery at the bend of the elbow.

Plate 14

COMMENTARY ON PLATES 15 & 16.

THE SURGICAL DISSECTION OF THE BEND OF THE ELBOW AND THE FOREARM, SHOWING THE
RELATIVE POSITION OF THE ARTERIES, VEINS, NERVES, &c.

The farther the surgical region happens to be removed from the centre of the
body, the less likely is it that all accidents or operations which involve such
regions will concern the life immediately. The limbs undergo all kinds of
mutilation, both by accident and intention, and yet the patient survives; but
when the like happens at any region of the trunk of the body, the life will be
directly and seriously threatened. It seems, therefore, that in the same degree
as the living principle diverges from the body’s centre into the outstanding
members, in that degree is the life weakened in intensity; and just as,
according to physical laws, the ray of light becomes less and less intense by
the square of the distance from the central source, so the vital ray, or vis,
loses momentum in the same ratio as it diverges from the common central line to
the periphery.

The relative anatomy of every surgical region becomes a study of more or less
interest to the surgeon, according to the degree of importance attaching to the
organs contained, or according to the frequency of such accidents as are liable
to occur in each. The bend of the elbow is a region of anatomical importance,
owing to the fact of its giving passage to C, Plate 15, the main artery of the
limb, and also because in it are located the veins D, B, E, F, which are
frequently the subject of operation. The anatomy of this region becomes,
therefore, important; forasmuch as the operation which is intended to concern
the veins alone, may also, by accident, include the main arterial vessel which
they overlie. The nerves, which are seen to accompany the veins superficially,
as well as that which accompanies the more deeply-situated artery, are, for the
same reason, required to be known.

The course of the brachial artery along the inner border of the biceps muscle
is comparatively superficial, from the point where it leaves the axilla to the
bend of the elbow. In the whole of this course it is covered by the fascia of
the arm, which serves to isolate it from the superficial basilic vein, B, and
the internal cutaneous nerve, both of which nevertheless overlie the artery.
The median nerve, d, Plate 15, accompanies the artery in its proper
sheath, which is a duplication of the common fascia; and in this sheath are
also situated the venae comites, making frequent loops around the artery. The
median nerve itself, D, Plate 16, takes a direct course down the arm; and the
different relative positions which this nerve holds in reference to the artery,
C, at the upper end, the middle, and the lower end of the arm, occur mainly in
consequence of the undulating character of the vessel itself.

When it is required to ligature the artery in the middle of the arm, the median
nerve will be found, in general, at its outer side, between it and the biceps;
but as the course of the artery is from the inner side of the biceps to the
middle of the bend of the elbow, so we find it passing under the nerve to gain
this locality, C, Plate 16, where the median nerve, D, then becomes situated at
the inner side of the vessel. The median nerve, thus found to be differently
situated in reference to the brachial artery, at the upper, the middle, and the
lower part of the arm, is (with these facts always held in memory) taken as the
guide to that vessel. An incision made of sufficient length (an inch and a
half, more or less) over the course of the artery, and to the outer side of the
basilic vein, B, Plate 16, will divide the skin, subcutaneous adipose membrane,
which varies much in thickness in several individuals, and will next expose the
common fascial envelope of the arm. When this fascia is opened, by dividing it
on the director, the artery becomes exposed; the median nerve is then to be
separated from the side of the vessel by the probe or director, and, with the
precaution of not including the venal comites, the ligature may now be passed
around the vessel. In the lower third of the arm it is not likely that the
operator will encounter the ulnar nerve, and mistake it for the median, since
the former, d, Plate 16, is considerably removed from the vessel. If the
incision be made precisely in the usual course of the brachial artery, the
ulnar nerve will not show itself. It will be well, however, to bear in mind the
possible occurrence of some of those anomalies to that normal relative position
of the artery, the median, and the ulnar nerve, which the accompanying Plates
represent.

The median nerve, D, Plate 16, is sometimes found to lie beneath the artery in
the middle and lower third of the arm. At other times it is found far removed
to the inner side of the usual position of the vessel, and lying in close
contact with the ulnar nerve, d. Or the brachial artery may take this
latter position, while the median nerve stands alone at the position of D,
Plate 16. Or both the main artery and the median nerve may course much to the
inner side of the biceps muscle, A, Plate 16, while in the usual situation of
the nerve and vessel there is only to be found a small arterial branch (the
radial), which springs from the brachial, high up in the arm. Or the nerve and
vessel may be lying concealed beneath a slip of the brachialis anticus muscle,
E, Plate 16, in which case no appearance of them will be at all manifested
through the usual place of incision made for the ligature of the brachial
vessel. Or, lastly, there may be found more arteries than the single main
brachial appearing at this place in the arm, and such condition of a plurality
of vessels occurs in consequence of a high division of the brachial artery.
Each of these variations from the normal type is more or less frequent; and
though it certainly is of practical import to bear them in mind, still, as we
never can foretell their occurrence by a superficial examination of the limb,
or pronounce them to be present till we actually encounter them in operation,
it is only when we find them that we commence to reason upon the facts; but
even at this crisis the knowledge of their anatomy may prevent a confusion of
ideas.

That generalization of the facts of such anomalies as are liable to occur to
the normal character of the brachial artery, represented in Plates 15 and 16,
which appears to me as being most inclusive of all their various conditions, is
this—viz., that the point of division into radial, ulnar, and interosseous,
which F, Plate 16, usually marks, may take place at any part of the member
between the bend of the elbow and the coracoid process in the axillary space.

At the bend of the elbow, the brachial artery usually occupies the middle point
between e, the inner condyle of the humerus and the external margin of
the supinator radii longus muscle, G. The structures which overlie the arterial
vessel, C, Plate 16, at this locality, numbering them from its own depth to the
cutaneous surface, are these— viz., some adipose cellular membrane envelopes
the vessel, as it lies on E, the brachialis anticus muscle, and between the two
accompanying veins; at the inner side of the artery, but separated from it by a
small interval occupied by one of the veins, is situated the median nerve
d, Plate 15. Above all three structures is stretched that dense fibrous
band of the fascia, H, Plate 16, which becomes incorporated with the common
fascial covering of the forearm. Over this fascial process lies the median
basilic vein, F B, Plate 15, accompanying which are seen some branches of the
internal cutaneous nerve. The subcutaneous adipose tissue and common integument
cover these latter. If it be required to ligature the artery at this locality,
an incision two inches and a half in length, made along the course of the
vessel, and avoiding the superficial veins, will expose the fascia; and this
being next divided on the director, the artery will be exposed resting on the
brachialis anticus, and between the biceps tendon and pronator teres muscle. As
this latter muscle differs in width in several individuals, sometimes lying in
close contact with the artery, and at other times leaving a considerable
interval between the vessel and itself, its outer margin is not, therefore, to
be taken as a sure guide to the artery. The inner border of the biceps
indicates much more generally the situation of the vessel.

The bend of the elbow being that locality where the operation of phlebotomy is
generally performed, it is therefore required to take exact account of the
structures which occupy this region, and more especially the relation which the
superficial veins hold to the deeper seated artery. In Plate 15, the artery, C,
is shown in its situation beneath the fascial aponeurosis, which comes off from
the tendon of the biceps, a portion of which has been cut away; and the venous
vessel, F B, which usually occupies the track of the artery, is pushed a little
to the inner side. While opening any part of the vessel, F B, which overlies
the artery, it is necessary to proceed with caution, as well because of the
fact that between the artery, C, and the vein, F B, the fascia alone
intervenes, as also because the ulnar artery is given off rather frequently
from the main vessel at this situation, and passes superficial to the fascia
and flexors of the forearm, to gain its usual position at K, Plate 15. I have
met with a well marked example of this occurrence in the living subject.

The cephalic vein, D, is accompanied by the external cutaneous nerve, which
branches over the fascia on the outer border of the forearm. The basilic vein,
B, is accompanied by the internal cutaneous nerve, which branches in a similar
way over the fascia of the inner and fore part of the forearm. The numerous
branches of both these nerves interlace with the superficial veins, and are
liable to be cut when these veins are being punctured. Though the median
basilic, F, and the basilic vein, B, are those generally chosen in the
performance of the operation of bleeding, it will be seen, in Plate 15, that
their contiguity to the artery necessarily demands more care and precision in
that operation executed upon them, than if D, the cephalic vein, far removed as
it is from the course of the artery, were the seat of phlebotomy.

As it is required, in order to distend the superficial veins, D, B, F, that a
band should be passed around the limb at some locality between them and the
heart, so that they may yield a free flow of blood on puncture, a moderate
pressure will be all that is needful for that end. It is a fact worthy of
notice, that the excessive pressure of the ligaturing band around the limb at A
B, Plate 15, will produce the same effect upon the veins near F, as if the
pressure were defective, for in the former case the ligature will obstruct the
flow of blood through the artery; and the vein, F, will hence be undistended by
the recurrent blood, just as when, in the latter case, the ligature, making too
feeble a pressure on the vein, B, will not obstruct its current in that degree
necessary to distend the vessel, F.

Whichever be the vein chosen for phlebotomy at the bend of the elbow, it will
be seen, from an examination of Plates 15 and 16, that the opening may be made
with most advantage according to the longitudinal axis of the vessel; for the
vessel while being cut open in this direction, is less likely to swerve from
the point of the lancet than if it were to be incised across, which latter mode
is also far more liable to implicate the artery. Besides, as the nerves course
along the veins from above downwards—making, with each other, and with the
vessels, but very acute angles—all incisions made longitudinally in these
vessels, will not be so likely to divide any of these nerves as when the
instrument is directed to cut crossways.

The brachial artery usually divides, at the bend of the elbow, into the radial,
the ulnar, and the interosseous branches. The point F, Plate 16, is the common
place of division, and this will be seen in the Plate to be somewhat below the
level of the inner condyle, e. From that place, where the radial and
ulnar arteries spring, these vessels traverse the forearm, in general under
cover of the muscles and fascia, but occasionally superficial to both these
structures. The radial artery, F N, Plate 16, takes a comparatively superficial
course along the radial border of the forearm, and is accompanied, for the
upper two-thirds of its length, by the radial branch of the musculo-spiral
nerve, seen in Plate 16, at the outer side of the vessel. The supinator radii
longus muscle in general overlaps, with its inner border, both the radial
artery and nerve. At the situation of the radial pulse, I, Plate 15, the artery
is not accompanied by the nerve, for this latter will be seen, in plate 16, to
pass outward, under the tendon of the supinator muscle, to the integuments.

The ulnar artery, whose origin is seen near F, Plate 16, passes deeply beneath
the superficial flexor muscles, L M K, and the pronator teres, I, and first
emerges from under cover of these at the point O, from which point to S, Plate
16, the artery may be felt, in the living body, obscurely beating as the ulnar
pulse. On the inner border of the ulnar artery, and in close connexion with it,
the ulnar nerve may be seen looped round by small branches of the vessel.

The radial and ulnar arteries may be exposed and ligatured in any part of their
course; but of the two, the radial vessel can be reached with greater facility,
owing to its comparatively superficial situation. The inner border of the
supinator muscle, G, Plate 16, is the guide to the radial artery; and the outer
margin of the flexor carpi ulnaris muscle, K, Plate 16, indicates the locality
of the ulnar artery. Both arteries, I, K, Plate 15, at the wrist, lie beneath
the fascia. If either of these vessels require a ligature in this region of the
arm, the operation may be performed with little trouble, as a simple incision
over the track of the vessels, through the skin and the fascia, will readily
expose each.

Whenever circumstances may call for placing a ligature on the ulnar artery, as
it lies between the superficial and deep flexor muscles, in the region of I L
M, Plate 16, the course of the vessel may be indicated by a line drawn from a
central point of the forearm, an inch or so below the level of the inner
condyle—viz., the point F, and carried to the pisiform bone, T. The line of
incision will divide obliquely the superficial flexors; and, on a full exposure
of the vessel in this situation, the median nerve will be seen to cross the
artery at an acute angle, in order to gain the mid-place in the wrist at Q. The
ulnar nerve, d, Plate 16, passing behind the inner condyle, e,
does not come into connexion with the ulnar artery until both arrive at the
place O. It will, however, be considered an awkward proceeding to subject to
transverse section so large a mass of muscles as the superficial flexors of the
forearm, when the vessel may be more readily reached elsewhere, and perhaps
with equal advantage as to the locality of the ligature.

When either the radial or ulnar arteries happen to be completely divided in a
wound, both ends of the vessel will bleed alike, in consequence of the free
anastomosis of both arteries in the hand.

DESCRIPTION OF PLATES 15 & 16.

PLATE 15.

A. Fascia covering the biceps muscle.

B. Basilic vein, with the internal cutaneous nerve.

C. Brachial artery, with the venae comites.

D. Cephalic vein, with the external cutaneous nerve; d, the median
nerve.

E. A communicating vein, joining the venae comites.

F. Median basilic vein.

G. Lymphatic gland.

H. Radial artery at its middle.

I. Radial artery of the pulse.

K. Ulnar artery, with ulnar nerve.

L. Palmaris brevis muscle.

Plate 15

PLATE 16.

A. Biceps muscle.

B. Basilic vein, cut.

C. Brachial artery.

D. Median nerve; d, the ulnar nerve.

E. Brachialis anticus muscle; e, the internal condyle.

F. Origin of radial artery.

G. Supinator radii longus muscle.

H. Aponeurosis of the tendon of the biceps muscle.

I. Pronator teres muscle.

K. Flexor carpi ulnaris muscle.

L. Flexor carpi radialis muscle.

M. Palmaris longus muscle.

N. Radial artery, at its middle, with the radial nerve on its outer side.

O. Flexor digitorum sublimis.

P. Flexor pollicis longus.

Q. Median nerve.

R. Lower end of radial artery.

S. Lower end of ulnar artery, in company with the ulnar nerve.

T. Pisiform bone.

U. Extensor metacarpi pollicis.

Plate 16

COMMENTARY ON PLATES 17, 18, & 19.

THE SURGICAL DISSECTION OF THE WRIST AND HAND.

A member of such vast importance as the human hand necessarily claims a high
place in regard to surgery. The hand is typical of the mind. It is the material
symbol of the immaterial spirit, It is the prime agent of the will; and it is
that instrument by which the human intellect manifests its presence in
creation. The human hand has a language of its own. While the tongue
demonstrates the thought through the word, the hand realizes and renders
visible the thought through the work. This organ, therefore, by whose fitness
of form the mind declares its own entity in nature, by the invention and
creation of the thing, which is, as it were, the mind’s autograph, claims a
high interest in surgical anatomy; and accordingly the surgeon lays it down as
a rule, strictly to be observed, that when this beautiful and valuable member
happens to be seriously mutilated, in any of those various accidents to which
it is exposed, the prime consideration should be, not as to the fact of how
much of its quantity or parts it can be deprived in operation, but rather as to
how little of its quantity should it be deprived, since no mechanical ingenuity
can fashion an apparatus, capable of supplying the loss of a finger, or even of
one of its joints.

The main blood vessels and nerves of the arm traverse the front aspect of the
wrist, and are distributed chiefly to supply the palmar surface of the hand,
since in the palm are to be found a greater variety and number of structures
than are met with on the back of the hand. The radial artery, A, Plate 17,
occupies (as its name indicates) the radial border of the forepart of the
wrist, and the ulnar artery, C, Plate 17, occupies the ulnar border; both
vessels in this region of their course lie parallel to each other; both are
comparatively superficial, but of the two, the radial artery is the more
superficial and isolated, and thereby occasions the radial pulse. The
anatomical situation of the radial artery accounts for the fact, why the
pulsation of this vessel is more easily felt than that of the ulnar artery.

The radial vessel, A, Plate 17, at the wrist, is not accompanied by the radial
nerve; for this nerve, C, Plate 19, passes from the side of the artery, at a
position, C, Plate 19, varying from one to two or more inches above the wrist,
to gain the dorsal aspect of the hand. The ulnar artery, C, Plate 17, is
attended by the ulnar nerve, D, in the wrist, and both these pass in company to
the palm. The ulnar nerve, D E, lies on the ulnar border of the artery, and
both are in general to be found ranging along the radial side of the tendon of
the flexor carpi ulnaris muscle, T, and the pisiform bone, G. The situation of
the radial artery is midway between the flexor carpi radialis tendon, I, and
the outer border of the radius. The deep veins, called comites, lie in
close connexion with the radial and ulnar arteries. When it is required to lay
bare the radial or ulnar artery, at the wrist, it will be sufficient for that
object to make a simple longitudinal incision (an inch or two in length) over
the course of the vessel A or C, Plate 17, through the integument, and this
incision will expose the fascia, which forms a common investment for all the
structures at this region. When this fascia has been cautiously slit open on
the director, the vessels will come into view. The ulnar artery, however, lies
somewhat concealed between the adjacent muscles, and in order to bring this
vessel fully into view, it will be necessary to draw aside the tendon of the
flexor ulnaris muscle, T.

The radial artery, A, Plate 18, passes external to the radial border of the
wrist, beneath the extensor tendons, B, of the thumb; and after winding round
the head of the metacarpal bone of the thumb, as seen at E, Plate 19, forms the
deep palmar arch E, Plate 18. This deep palmar arch lies close upon the
forepart of the carpo-metacarpal joints; it sends off branches to supply the
deeply situated muscles, and other structures of the palm; and from it are also
derived other branches, which pierce the interosseal spaces, and appear on the
back of the hand, Plate 19. The deep palmar arch, E, Plate 18, inosculates with
a branch of the ulnar artery, I, Plate 18, whilst its dorsal interosseal
branches, Plate 19, communicate freely with the dorsal carpal arch, which is
formed by a branch of the radial artery E, Plate 19, and the terminal branch of
the posterior interosseous vessel.

The ulnar artery, C, Plate 17, holds a direct and superficial course, from the
ulnar border of the forearm through the wrist; and still remains superficial in
the palm, where it forms the superficial palmar arch, F. From this arch arise
three or four branches of considerable size, which are destined to supply the
fingers. A little above the interdigital clefts, each of these digital arteries
divides into two branches, which pass along the adjacent sides of two fingers—a
mode of distribution which also characterises the digital branches of the
median, b b, and ulnar nerves, e e. The superficial palmar arch
of the ulnar vessel anastomoses with the deep arch of the radial vessel. The
principal points of communication are, first, by the branch, (ramus profundus,)
I, Plate 18, which passes between the muscles of the little finger to join the
deep arch beneath the long flexor tendons. 2nd, by the branch (superficialis
volae) which springs from the radial artery, A, Plate 17, and crosses the
muscles of the ball of the thumb, to join the terminal branch of the
superficial arch, F, Plate 17. 3rd, by another terminal branch of the
superficial arch, which joins the arteries of the thumb, derived from the
radial vessel, as seen at e, Plate 18.

The frequent anastomosis thus seen to take place between the branches of the
radial, the ulnar, and the interosseous arteries in the hand, should be
carefully borne in mind by the surgeon. The continuity of the three vessels by
anastomosis, renders it very difficult to arrest a haemorrhage occasioned by a
wound of either of them. It will be at once seen, that when a haemorrhage takes
place from any of these larger vessels of the hand, the bleeding will not be
commanded by the application of a ligature to either the radial, the ulnar, or
the interosseous arteries in the forearm; and for this plain reason, viz., that
though in the arm these arteries are separate, in the hand their communication
renders them as one.

If a haemorrhage therefore take place from either of the palmar vessels, it
will not be sufficient to place a ligature around the radial or the ulnar
artery singly, for if F, Plate 17, bleeds, and in order to arrest that bleeding
we tie the vessel C, Plate 17, still the vessel F will continue to bleed, in
consequence of its communication with the vessel E, Plate 18, by the branch 1,
Plate 18, and other branches above mentioned. If E, Plate 18, bleeds, a
ligature applied to the vessel A, Plate 18, will not stop the flow of blood,
because of the fact that E anastomoses with G, by the branch I and other
branches, as seen in Plates 17 and 19.

Any considerable haemorrhage, therefore, which may be caused by a wound of the
superficial or deep palmar arches, or their branches, and which we are unable
to arrest by compression, applied directly to the patent orifices of the
vessel, will in general require that a ligature be applied to both the radial
and ulnar arteries at the wrist; and it occasionally happens that even this
proceeding will not stop the flow of blood, for the interosseous arteries,
which also communicate with the vessels of the hand, may still maintain the
current of circulation through them. These interosseous arteries being branches
of the ulnar artery, and being given off from the vessel at the bend of the
elbow, if the bleeding be still kept up from the vessel wounded in the hand,
after the ligature of the ulnar and radial arteries is accomplished, are in all
probability the channels of communication, and in this case the brachial artery
must be tied. A consideration of the above mentioned facts, proper to the
normal distribution of the vessels of the upper extremity, will explain to the
practitioner the cause of the difficulty which occasionally presents itself, as
to the arrest of haemorrhage from the vessels of the hand. In addition to these
facts he will do well to remember some other arrangements of these vessels,
which are liable to occur; and upon these I shall offer a few observations.

While I view the normal disposition of the arteries of the arm as a whole, (and
this view of the whole great fact is no doubt necessary, if we would take
within the span and compass of the reason, all the lesser facts of which the
whole is inclusive,) I find that as one main vessel (the brachial) divides into
three lesser branches, (the ulnar, radial and interosseous,) so, therefore,
when either of these three supplies the haemorrhage, and any difficulty arises
preventing our having access at once to the open orifices of the wounded
vessel, we can command the flow of blood by applying a ligature to the main
trunk—the brachial. If this measure fail to command the bleeding, then we may
conclude that the wounded vessel (whichever it happen to be, whether the
radial, the ulnar, or the interosseous) arises from the brachial artery, higher
up in the arm than that place whereat we applied the ligature. To this variety
as to the place of origin, the ulnar, radial, and interosseous arteries are
individually liable.

Again, as the single brachial artery divides into the three arteries of the
forearm, and as these latter again unite into what may (practically speaking)
be termed a single vessel in the hand, in consequence of their anastomosis, so
it is obvious that in order to command a bleeding from any of the palmar
arteries, we should apply a ligature upon each of the vessels of the forearm,
or upon the single main vessel in the arm. When the former proceeding fails, we
have recourse to the latter, and when this latter fails (for fail it will,
sometimes,) we then reasonably arrive at the conclusion that some one of the
three vessels of the forearm, springs higher up than the place of the ligature
on the main brachial vessel.

But however varied as to the normal locality of their origin, at the bend of
the elbow, these vessels of the forearm may at times manifest themselves, still
one point is quite fixed and certain, viz., that they communicate with each
other in the hand. Hence, therefore, it becomes evident, that in order to
command, at once and effectually, a bleeding, either from the palmar arteries,
or those of the forearm, we attain to a more sure and successful result, the
nearer we approach the fountain-head and place a ligature on it—the brachial
artery. It is true that to stop the circulation through the main vessel of the
limb, is always attended with danger, and that such a proceeding is never to be
adopted but as the lesser one of two great hazards. It is also true that to tie
the main brachial artery for a haemorrhage of anyone of its terminal branches,
may be doing too much, while a milder course may serve; or else that even our
tying the brachial may not suffice, owing to a high distribution of the vessels
of the arm, in the axilla, above the place of the ligature. Thus doubt as to
the safest measure, viz., that which is sufficient and no more, enveils the
proper place whereat to apply a ligature on the principal vessel; but whatever
be the doubt as to this particular, there can be none attending the following
rule of conduct, viz., that in all cases of haemorrhage, caused by wounds of
the vessels of the upper limb, we should, if at all practicable, endeavour to
stop the flow of blood from the divided vessels in the wound itself, by
ligature or otherwise; and both ends of the divided vessel require to be tied.
Whenever this may be done, we need not trouble ourselves concerning the anomaly
in vascular distribution.

The superficial palmar arch, F, Plate 17, lies beneath the dense palmar fascia;
and whenever matter happens to be pent up by this fascia, and it is necessary
that an opening be made for its exit, the incision should be conducted at a
distance from the locality of the vessel. When matter forms beneath the palmar
fascia, it is liable, owing to the unyielding nature of this fibrous structure,
to burrow upwards into the forearm, beneath the annular ligament D, Plates 17
and 18. All deep incisions made in the median line of the forepart of the wrist
are liable to wound the median nerve B, Plate 17. When the thumb, together with
its metacarpal bone, is being amputated, the radial artery E, Plate 19, which
winds round near the head of that bone, may be wounded. It is possible, by
careful dissection, to perform this operation without dividing the radial
vessel.

DESCRIPTION OF PLATES 17, 18, & 19.

PLATE 17.

A. Radial artery.

B. Median nerve; b b b b, its branches to the thumb and fingers.

C. Ulnar artery, forming F, the superficial palmar arch.

D. Ulnar nerve; E e e, its continuation branching to the little and ring
fingers, &c.

G. Pisiform bone.

H. Abductor muscle of the little finger.

I. Tendon of flexor carpi radialis muscle.

K. Opponens pollicis muscle.

L. Flexor brevis muscle of the little finger.

M. Flexor brevis pollicis muscle.

N. Abductor pollicis muscle.

OOOO. Lumbricales muscles.

P P P P. Tendons of the flexor digitorum sublimis muscle.

Q. Tendon of the flexor longus pollicis muscle.

R. Tendon of extensor metacarpi pollicis.

S. Tendons of extensor digitorum sublimis; P P P, their digital prolongations.

T. Tendon of flexor carpi ulnaris.

U. Union of the digital arteries at the tip of the finger.

Plate 17

PLATE 18.

A. Radial artery.

B. Tendons of the extensors of the thumb.

C. Tendon of extensor carpi radialis.

D. Annular ligament.

E. Deep palmar arch, formed by radial artery giving off e, the artery of
the thumb.

F. Pisiform bone.

G. Ulnar artery, giving off the branch I to join the deep palmar arch E of the
radial artery.

H. Ulnar nerve; h, superficial branches given to the fingers. Its deep
palmar branch is seen lying on the interosseous muscles, M M.

K. Abductor minimi digiti.

L. Flexor brevis minimi digiti.

M. Palmar interosseal muscles.

N. Tendons of flexor digitorum sublimis and profundus, and the lumbricales
muscles cut and turned down.

O. Tendon of flexor pollicis longus.

P. Carpal end of the metacarpal bone of the thumb.

Plate 18

PLATE 19. AAA. Tendons of extensor digitorum communis; A*, tendon overlying
that of the indicator muscle.

B. Dorsal part of the annular ligament.

C. End of the radial nerve distributed over the back of the hand, to two of the
fingers and the thumb.

D. Dorsal branch of the ulnar nerve supplying the back of the hand and the
three outer fingers.

E. Radial artery turning round the carpal end of the metacarpal bone of the
thumb.

F. Tendon of extensor carpi radialis brevis.

G. Tendon of extensor carpi radialis longus.

H. Tendon of third extensor of the thumb.

I. Tendon of second extensor of the thumb.

K. Tendon of extensor minimi digiti joining a tendon of extensor communis.

Plate 19

COMMENTARY ON PLATES 20 & 21.

THE RELATIVE POSITION OF THE CRANIAL, NASAL, ORAL, AND PHARYNGEAL CAVITIES,
&c.

On making a section (vertically through the median line) of the cranio-facial
and cervico-hyoid apparatus, the relation which these structures bear to each
other in the osseous skeleton reminds me strongly of the great fact enunciated
by the philosophical anatomists, that the facial apparatus manifests in
reference to the cranial structures the same general relations which the hyoid
apparatus bears to the cervical vertebrae, and that these relations are similar
to those which the thoracic apparatus bears to the dorsal vertebrae. To this
anatomical fact I shall not make any further allusions, except in so far as the
acknowledgment of it shall serve to illustrate some points of surgical import.

The cranial chamber, A A H, Plate 20, is continuous with the spinal canal C.
The osseous envelope of the brain, called calvarium, Z B, holds serial order
with the cervical spinous processes, E I, and these with the dorsal spinous
processes. The dura-matral lining membrane, A A A*, of the cranial chamber is
continuous with the lining membrane, C, of the spinal canal. The brain is
continuous with the spinal cord. The intervertebral foramina of the cervical
spine are manifesting serial order with the cranial foramina. The nerves which
pass through the spinal region of this series of foramina above and below C are
continuous with the nerves which pass through the cranial region. The anterior
boundary, D I, of the cervical spine is continuous with the anterior boundary,
Y F, of the cranial cavity. And this common serial order of osseous parts—viz.,
the bodies of vertebrae, serves to isolate the cranio-spinal compartment from
the facial and cervical passages. Thus the anterior boundary, Y F D I, of the
cranio-spinal canal is also the posterior boundary of the facial and cervical
cavities.

Now as the cranio-spinal chamber is lined by the common dura-matral membrane,
and contains the common mass of nervous structure, thus inviting us to fix
attention upon this structure as a whole, so we find that the frontal cavity,
Z, the nasal cavity, X W, the oral cavity, 4, 5, S, the pharyngeal and
oesophageal passages 8 Q, are lined by the common mucous membrane, and
communicate so freely with each other that they may be in fact considered as
forming a common cavity divided only by partially formed septa, such as the
one, U V, which separates to some extent the nasal fossa from the oral fossa.

As owing to this continuity of structure, visible between the head and spine,
we may infer the liability which the affections of the one region have to pass
into and implicate the other, so likewise by that continuity apparent between
all compartments of the face, fauces, oesophagus, and larynx, we may estimate
how the pathological condition of the one region will concern the others.

The cranium, owing to its comparatively superficial and undefended condition,
is liable to fracture. When the cranium is fractured, in consequence of force
applied to its anterior or posterior surfaces, A or B, Plate 20, the fracture
will, for the most part, be confined to the place whereat the force has been
applied, provided the point opposite has not been driven against some resisting
body at the same time. Thus when the point B is struck by a force sufficient to
fracture the bone, while the point A is not opposed to any resisting body, then
B alone will yield to the force applied; and fracture thus occurring at the
point B, will have happened at the place where the applied force is met by the
force, or weight, or inertia of the head itself. But when B is struck by any
ponderous body, while A is at the same moment forced against a resisting body,
then A is also liable to suffer fracture. If fracture in one place be attended
with counter-fracture in another place, as at the opposite points A and B, then
the fracture occurs from the force impelling, while the
counter-fracture happens by the force resisting.

Now in the various motions which the cranium A A B performs upon the top of the
cervical spine C, motions backwards, forwards, and to either side, it will
follow that, taking C as a fixed point, almost all parts of the cranial
periphery will be brought vertical to C in succession, and therefore whichever
point happens at the moment to stand opposite to C, and has impelling force
applied to it, then C becomes the point of resistance, and thus
counter-fractures at the cranial base occur in the neighbourhood of C. When
force is applied to the cranial vertex, whilst the body is in the erect
posture, the top of the cervical spine, E D C, becomes the point of resistance.
Or if the body fall from a height upon its cranial vertex, then the propelling
force will take effect at the junction of the spine with the cranial base,
whilst the resisting force will be the ground upon which the vertex strikes. In
either case the cranial base, as well as the vertex, will be liable to
fracture.

The anatomical form of the cranium is such as to obviate a frequent liability
to fracture. Its rounded shape diffuses, as is the case with all rotund forms,
the force which happens to strike upon it. The mode in which the cranium is set
upon the cervical spine serves also to diffuse the pressure at the points where
the two opposing forces meet—viz., at the first cervical vertebra E and the
cranial basilar process F. This fact might be proved upon mechanical principle.

The tegumentary envelope of the head, as well as the dura-matral lining, serves
to damp cranial vibration consequent upon concussion; while the sutural
isolation of the several component bones of the cranium also prevents, in some
degree, the extension of fractures and the vibrations of concussion. The
contents of the head, like the contents of all hollow forms, receive the
vibratory influence of force externally applied. The brain receives the
concussion of the force applied to its osseous envelope; and when this latter
happens to be fractured, the danger to life is not in proportion to the extent
of the fracture here, any more than elsewhere in the skeleton fabric, but is
solely in proportion to the amount of shock or injury sustained by the nervous
centre.

When it is required to trephine any part of the cranial envelope, the points
which should be avoided, as being in the neighbourhood of important
bloodvessels, are the following—the occipital protuberance, B, within which the
“torcular Herophili” is situated, and from this point passing through the
median line of the vertex forwards to Z the frontal sinus, the trephine should
not be applied, as this line marks the locality of the superior longitudinal
sinus. The great lateral sinus is marked by the superior occipital ridge
passing from the point B outwards to the mastoid process. The central point B
of the side of the head, Plate 21, marks the locality of the root of the
meningeal artery within the cranium, and from this point the vessel branches
forwards and backwards over the interior of the cranium.

The nasal fossae are situated on either side of the median partition formed by
the vomer and cartilaginous nasal septum. Both nasal fossae are open anteriorly
and posteriorly; but laterally they do not, in the normal state of these parts,
communicate. The two posterior nares answering to the two nasal fossae open
into the upper part of the bag of the pharynx at 8, Plate 20, which marks the
opening of the Eustachian tube.

The structures observable in both the nasal fossae absolutely correspond, and
the foramina which open into each correspond likewise. All structures situated
on either side of the median line are similar. And the structure which occupies
the median line is itself double, or duality fused into symmetrical unity. The
osseous nasal septum is composed of two laminae laid side by side. The spongy
bones, X W, are attached to the outer wall of the nasal fossa, and are situated
one above the other. These bones are three in number, the uppermost is the
smallest. The outer wall of each naris is grooved by three fossae, called
meatuses, and these are situated between the spongy bones. Each meatus receives
one or more openings of various canals and cavities of the facial apparatus.
The sphenoidal sinus near F opens into the upper meatus. The frontal, Z, and
maxillary sinuses open into the middle meatus, and the nasal duct opens into
the inferior sinus beneath the anterior inferior angle of the lower spongy
bone, W.

In the living body the very vascular fleshy and glandular Schneiderian membrane
which lines all parts of the nasal fossa almost completely fills this cavity.
When polypi or other growths occupy the nasal fossae, they must gain room at
the expense of neighbouring parts. The nasal duct may have a bent probe
introduced into it by passing the instrument along the outer side of the floor
of the nasal fossa as far back as the anterior inferior angle of the lower
spongy bone, W, at which locality the duct opens. An instrument of sufficient
length, when introduced into the nostrils in the same direction, will, if
passed backwards through the posterior nares, reach the opening of the
Eustachian tube, 8.

While the jaws are closed, the tongue, R, Plate 20, occupies the oral cavity
almost completely. When the jaws are opened they form a cavity between them
equal in capacity to the degree at which they are sundered from each other. The
back of the pharynx can be seen when the jaws are widely opened if the tongue
be depressed, as R, Plate 20. The hard palate, U, which forms the roof of the
mouth, is extended further backwards by the soft palate, V, which hangs as the
loose velum of the throat between the nasal fossae above and the fauces below.
Between the velum palati, V, and the root of the tongue, we may readily
discern, when the jaws are open, two ridges of arching form, 5, 6, on either
side of the fauces. These prominent arches and their fellows are named the
pillars of the fauces. The anterior pillar, 5, is formed by the submucous
palato-glossus muscle; the posterior pillar, 6, is formed by the
palato-pharyngeus muscle. Between these pillars, 5 and 6, is situated the
tonsil, S, beneath the mucous membrane. When the tonsils of opposite sides
become inflamed and suppurate, an incision may be made into either gland
without much chance of wounding the internal carotid artery; for, in fact, this
vessel lies somewhat removed from it behind. In Plate 21, that point of the
superior constrictor of the pharynx, marked D, indicates the situation of the
tonsil gland; and a considerable interval will be seen to exist between D and
the internal carotid vessel F.

If the head be thrown backwards the nasal and oral cavities will look almost
vertically towards the pharyngeal pouch. When the juggler is about to “swallow
the sword,” he throws the head back so as to bring the mouth and fauces in a
straight line with the pharynx and oesophagus. And when the surgeon passes the
probang or other instruments into the oesophagus, he finds it necessary to give
the head of the person on whom he operates the same inclination backwards. When
instruments are being passed into the oesophagus through the nasal fossa, they
are not so likely to encounter the rima glottidis below the epiglottis, 9, as
when they are being passed into the oesophagus by the mouth. The glottis may be
always avoided by keeping the point of the instrument pressing against the back
of the pharynx during its passage downwards.

When in suspended animation we endeavour to inflate the lungs through the nose
or mouth, we should press the larynx, 10, 11,12, backwards against the
vertebral column, so as to close the oesophageal tube.

DESCRIPTION OF PLATES 20 & 21.

PLATE 20.

A A. The dura-matral falx; A*, its attachment to the tentorium.

B. Torcular Herophili.

C. Dura-mater lining the spinal canal.

D D*. Axis vertebra.

E E*. Atlas vertebra.

F F*. Basilar processes of the sphenoid and occipital bones.

G. Petrous part of the temporal bone.

H. Cerebellar fossa.

I I*. Seventh cervical vertebra.

K K*. First rib surrounding the upper part of the pleural sac.

L L*. Subclavian artery of the right side overlying the pleural sac.

M M*. Right subclavian vein.

N. Right common carotid artery cut at its origin.

O. Trachea.

P. Thyroid body.

Q. Oesophagus.

R. Genio-hyo-glossus muscle.

S. Left tonsil beneath the mucous membrane.

T. Section of the lower maxilla.

U. Section of the upper maxilla.

V. Velum palati in section.

W. Inferior spongy bone.

X. Middle spongy bone.

Y. Crista galli of oethmoid bone.

Z. Frontal sinus.

2. Anterior cartilaginous part of nasal septum.

3. Nasal bone.

4. Last molar tooth of the left side of lower jaw.

5. Anterior pillar of the fauces.

6. Posterior pillar of the fauces.

7. Genio-hyoid muscle.

8. Opening of Eustachian tube.

9. Epiglottis.

10. Hyoid bone.

11. Thyroid bone.

12. Cricoid bone.

13. Thyroid axis.

14. Part of anterior scalenus muscle.

15. Humeral end of the clavicle.

16. Part of posterior scalenus muscle.

Plate 20

PLATE 21.

A. Zygoma.

B. Articular glenoid fossa of temporal bone.

C. External pterygoid process lying on the levator and tensor palati muscles.

D. Superior constrictor of pharynx.

E. Transverse process of the Atlas.

F. Internal carotid artery. Above the point F, is seen the glosso-pharyngeal
nerve; below F, is seen the hypoglossal nerve.

G. Middle constrictor of pharynx.

H. Internal jugular vein.

I. Common carotid cut across.

K. Rectus capitis major muscle.

L. Inferior constrictor of pharynx.

M. Levator anguli scapulae muscle.

N. Posterior scalenus muscle.

O. Anterior scalenus muscle.

P. Brachial plexus of nerves.

Q. Trachea.

R R*. Subclavian artery.

S. End of internal jugular vein.

T. Bracheo-cephalic artery.

U U*. Roots of common carotid arteries.

V. Thyroid body.

W. Thyroid cartilage.

X. Hyoid bone.

Y. Hyo-glossus muscle.

Z. Upper maxillary bone.

2. Inferior maxillary branch of fifth cerebral nerve.

3. Digastric muscle cut.

4. Styloid process.

5. External carotid artery.

6 6. Lingual artery.

7. Roots of cervical plexus of nerves.

8. Thyroid axis; 8*, thyroid artery, between which and Q, the trachea, is seen
the inferior laryngeal nerve.

9. Omo-hyoid muscle cut.

10. Sternal end of clavicle.

11. Upper rings of trachea, which may with most safety be divided in
tracheotomy.

12. Cricoid cartilage.

13. Crico-thyroid interval where laryngotomy is performed.

14. Genio-hyoid muscle.

15. Section of lower maxilla.

16. Parotid duct.

17. Lingual attachment of styloglossus muscle, with part of the gustatory nerve
seen above it.

Plate 21

COMMENTARY ON PLATE 22.

THE RELATIVE POSITION OF THE SUPERFICIAL ORGANS OF THE THORAX AND ABDOMEN.

In the osseous skeleton, the thorax and abdomen constitute a common
compartment. We cannot, while we contemplate this skeleton, isolate the one
region from the other by fact or fancy. The only difference which I can
discover between the regions called thorax and abdomen, in the osseous
skeleton, (considering this body morphologically,) results, simply, from the
circumstance that the ribs, which enclose thoracic space, have no osseous
counterparts in the abdomen enclosing abdominal space, and this difference
is merely histological. In man and the mammalia the costal arches hold relation
with the pulmonary organs, and these costae fail at that region where the
ventral organs are located. In birds, and many reptiles, the costal arches
enclose the common thoracico-abdominal region, as if it were a common pulmonary
region. In fishes the costal arches enclose the thoracico-abdominal region,
just as if it were a common abdominal region. I merely mention these general
facts to show that costal enclosure does not actually serve to isolate the
thorax from the abdomen in the lower classes of animals; and on turning to the
human form, I find that this line of separation between the two compartments is
so very indefinite, that, as pathologists, we are very liable to err in our
diagnosis between the diseased and the healthy organs of either region, as they
lie in relation with the moveable diaphragm or septum in the living body. The
contents of the whole trunk of the body from the top of the sternum to the
perineum are influenced by the respiratory motions; and it is most true that
the diaphragmatic line, H F H*, is alternately occupied by those organs
situated immediately above and below it during the performance of these
motions, even in health.

The organs of the thoracic region hold a certain relation to each other and to
the thoracic walls. The organs of the abdomen hold likewise a certain relation
to each other and to the abdominal parietes. The organs of both the thorax and
the abdomen have a certain relation to each other, as they lie above and below
the diaphragm. In dead nature these relations are fixed and readily
ascertainable, but in living, moving nature, the organs influence this relative
position, not only of each other, but also of that which they bear to the
cavities in which they are contained. This change of place among the organs
occurs in the normal or healthy state of the living body, and, doubtless,
raises some difficulty in the way of our ascertaining, with mathematical
precision, the actual state of the parts which we question, by the physical
signs of percussion and auscultation. In disease this change of place among
these organs is increased, and the difficulty of making a correct diagnosis is
increased also in the same ratio. For when an emphysematous lung shall fully
occupy the right thoracic side from B to L, then G, the liver, will protrude
considerably into the abdomen beneath the right asternal ribs, and yet will not
be therefore proof positive that the liver is diseased and abnormally enlarged.
Whereas, on the other hand, when G, the liver, is actually diseased, it may
occupy a situation in the right side as high as the fifth or sixth ribs,
pushing the right lung upwards as high as that level; and, therefore, while
percussion elicits a dull sound over this place thus occupied, such sound will
not be owing to a hepatized lung, but to the absence of the lung caused by the
presence of the liver.

In the healthy adult male body, Plate 22, the two lungs, D D*, whilst in their
ordinary expanded state, may be said to range over all that region of the trunk
of the body which is marked by the sternal and asternal ribs. The heart, E,
occupies the thoracic centre, and part of the left thoracic side. The heart is
almost completely enveloped in the two lungs. The only portion of the heart and
pericardium, which appears uncovered by the lung on opening the thorax, is the
base of the right ventricle, E, situated immediately behind the lower end of
the sternum, where this bone is joined by the cartilages of the sixth and
seventh ribs. The lungs range perpendicularly from points an inch above B, the
first rib, downwards to L, the tenth rib, and obliquely downwards and backwards
to the vertebral ends of the last ribs. This space varies in capacity,
according to the degree in which the lungs are expanded within it. The increase
in thoracic space is attained, laterally, by the expansion of the ribs, C I;
and vertically, by the descent of the diaphragm, H, which forces downwards the
mass of abdominal viscera. The contraction of thoracic space is caused by the
approximation of all the ribs on each side to each other; and by the ascent of
the diaphragm. The expansion of the lungs around the heart would compress this
organ, were it not that the costal sides yield laterally while the diaphragm
itself descends. The heart follows the ascent and descent of the diaphragm,
both in ordinary and forced respiration.

But however much the lungs vary in capacity, or the heart as to position in the
respiratory motions, still the lungs are always closely applied to the thoracic
walls. Between the pleura costalis and pulmonalis there occurs no interval in
health. The thoracic parietes expand and contract to a certain degree; and to
that same degree, and no further, do the lungs within the thorax expand and
contract. By no effort of expiration can the animal expel all the air
completely from its lungs, since by no effort of its own, can it contract
thoracic space beyond the natural limit. On the other hand, the utmost degree
of expansion of which the lungs are capable, exactly equals that degree in
which the thoracic walls are dilatable by the muscular effort; and, therefore,
between the extremes of inspiration and expiration, the lungs still hold
closely applied to the costal parietes. The air within the lungs is separated
from the air external to the thorax, by the thoracic parietes. The air within
and external to the lungs communicate at the open glottis. When the glottis
closes and cuts off the communication, the respiratory act ceases—the lungs
become immovable, and the thoracic walls are (so far as the motions of
respiration are concerned) rendered immovable also. The muscles of respiration
cannot, therefore, produce a vacuum between the pulmonic and costal pleura,
either while the external air has or has not access to the lungs. Upon this
fact the mechanism of respiration mainly depends; and we may see a still
further proof of this in the circumstance that, when the thoracic parietes are
pierced, so as to let the external air into the cavity of the pleura, the lung
collapses and the thoracic side ceases to exert an expansile influence over the
lung. When in cases of fracture of the rib the lung is wounded, and the air of
the lung enters the pleura, the same effect is produced as when the external
air was admitted through an opening in the side.

When serous or purulent effusion takes place within the cavity of the pleura,
the capacity of the lung becomes lessened according to the quantity of the
effusion. It is more reasonable to expect that the soft tissue of the lung
should yield to the quantity of fluid within the pleural cavity, than that the
rigid costal walls should give way outwardly; and, therefore, it seldom happens
that the practitioner can discover by the eye any strongly-marked difference
between the thoracic walls externally, even when a considerable quantity of
either serum, pus, or air, occupies the pleural sacs.

In the healthy state of the thoracic organs, a sound characteristic of the
presence of the lung adjacent to the walls of the thorax may be elicited by
percussion, or heard during the respiratory act through the stethoscope, over
all that costal space ranging anteriorly between B, the first rib, and I K, the
eight and ninth ribs. The respiratory murmur can be heard below the level of
these ribs posteriorly, for the lung descends behind the arching diaphragm as
far as the eleventh rib.

When fluid is effused into the pleural cavity, the ribs are not moved by the
intercostal muscles opposite the place occupied by the fluid, for this has
separated the lung from the ribs. The fluid has compressed the lung; and in the
same ratio as the lung is prevented from expanding, the ribs become less
moveable. The presence of fluid in the pleural sac is discoverable by dulness
on percussion, and, as might be expected, by the absence of the respiratory
murmur at that locality which the fluid occupies. Fluid, when effused into the
pleural sac, will of course gravitate; and its position will vary according to
the position of the patient. The sitting or standing posture will therefore
suit best for the examination of the thorax in reference to the presence of
fluid.

Though the lungs are closely applied to the costal sides at all times in the
healthy state of these organs, still they slide freely within the thorax during
the respiratory motions—forwards and backwards—over the serous pericardium, E,
and upwards and downwards along the pleura costalis. The length of the
adhesions which supervene upon pleuritis gives evidence of the extent of these
motions. When the lung becomes in part solidified and impervious to the
inspired air, the motions of the thoracic parietes opposite to the part are
impeded. Between a solidified lung and one which happens to be compressed by
effused fluid it requires no small experience to distinguish a difference,
either by percussion or the use of the stethoscope. It is great experience
alone that can diagnose hydro-pericardium from hypertrophy of the substance of
the heart by either of these means.

The thoracic viscera gravitate according to the position of the body. The heart
in its pericardial envelope sways to either side of the sternal median line
according as the body lies on this or that side. The two lungs must, therefore,
be alternately affected as to their capacity according as the heart occupies
space on either side of the thorax. In expiration, the heart, E, is more
uncovered by the shelving edges of the lungs than in inspiration. In
pneumothorax of either of the pleural sacs the air compresses the lung, pushes
the heart from its normal position, and the space which the air occupies in the
pleura yields a clear hollow sound on percussion, whilst, by the ear or
stethoscope applied to a corresponding part of the thoracic walls, we discover
the absence of the respiratory murmur.

The transverse diameter of the thoracic cavity varies at different levels from
above downwards. The diameter which the two first ribs, B B*, measure, is the
least. That which is measured by the two eighth ribs, I I*, is the greatest.
The perpendicular depth of the thorax, measured anteriorly, ranges from A, the
top of the sternum, to F, the xyphoid cartilage. Posteriorly, the perpendicular
range of the thoracic cavity measures from the spinous process of the seventh
cervical vertebra above, to the last dorsal spinous process below. In full,
deep-drawn inspiration in the healthy adult, the ear applied to the thoracic
walls discovers the respiratory murmur over all the space included within the
above mentioned bounds. After extreme expiration, if the thoracic walls be
percussed, this capacity will be found much diminished; and the extreme limits
of the thoracic space, which during full inspiration yielded a clear sound,
indicative of the presence of the lung, will now, on percussion, manifest a
dull sound, in consequence of the absence of the lung, which has receded from
the place previously occupied.

Owing to the conical form of the thoracic space, the apex of which is measured
by the first ribs, B B*, and the basis by I I*, it will be seen that if
percussion be made directly from before, backwards, over the pectoral masses, R
R*, the pulmonic resonance will not be elicited. When we raise the arms from
the side and percuss the thorax between the folds of the axillae, where the
serratus magnus muscle alone intervenes between the ribs and the skin, the
pulmonic sound will answer clearly.

At the hypochondriac angles formed between the points F, L, N, on either side
the lungs are absent both in inspiration and expiration. Percussion, when made
over the surface of the angle of the right side, discovers the presence of the
liver, G G*. When made over the median line, and on either side of it above the
umbilicus, N, we ascertain the presence of the stomach, M M*. In the left
hypochondriac angle, the stomach may also be found to occupy this place wholly.

Beneath the umbilicus, N, and on either side of it as far outwards as the lower
asternal ribs, K L, thus ranging the abdominal parietes transversely,
percussion discovers the transverse colon, O, P, O*. The small intestines, S
S*, covered by the omentum, P*, occupy the hypogastric and iliac regions.

The organs situated within the thorax give evidence that they are developed in
accordance to the law of symmetry. The lungs form a pair, one placed on either
side of the median line. The heart is a double organ, formed of the right and
left heart. The right lung differs from the left, inasmuch as we find the
former divided into three lobes, while the latter has only two. That place
which the heart now occupies in the left thoracic side is the place where the
third or middle lobe of the left lung is wanting. In the abdomen we find that
most of its organs are single. The liver, stomach, spleen, colon, and small
intestine form a series of single organs: each of these may be cleft
symmetrically. The kidneys are a pair.

The extent to which the ribs are bared in the figure Plate 22, marks exactly
the form and transverse capacity of the thoracic walls. The diaphragm, H H*,
has had a portion of its forepart cut off, to show how it separates the thin
edges of both lungs above from the liver, G, and the stomach, M, below. These
latter organs, although occupying abdominal space, rise to a considerable
height behind K L, the asternal ribs, a fact which should be borne in mind when
percussing the walls of the thorax and abdomen at this region.

DESCRIPTION OF PLATE 22.

A. Upper bone of the sternum.

B B*. Two first ribs.

C C*. Second pair of ribs.

D D*. Right and left lungs.

E. Pericardium, enveloping the heart—the right ventricle.

F. Lower end of the sternum.

G G*. Lobes of the liver.

H H*. Right and left halves of the diaphragm in section. The right half
separating the right lung from the liver; the left half separating the left
lung from the broad cardiac end of the stomach.

I I*. Eighth pair of ribs.

K K*. Ninth pair of ribs.

L L*. Tenth pair of ribs.

M M*. The stomach; M, its cardiac bulge; M*, its pyloric extremity.

N. The umbilicus.

OO*. The transverse colon.

P P*. The omentum, covering the transverse colon and small intestines.

Q. The gall bladder.

R R*. The right and left pectoral prominences.

S S*. Small intestines.

Plate 22

COMMENTARY ON PLATE 23.

THE RELATIVE POSITION OF THE DEEPER ORGANS OF THE THORAX AND THOSE OF THE
ABDOMEN.

The size or capacity of the thorax in relation to that of the abdomen varies in
the individual at different periods of life. At an early age, the thorax,
compared to the abdomen, is less in proportion than it is at adult age. The
digestive organs in early age preponderate considerably over the respiratory
organs; whereas, on the contrary, in the healthy and well-formed adult, the
thoracic cavity and organs of respiration manifest a greater relative
proportion to the ventral cavity and organs. At the adult age, when sexual
peculiarities have become fully marked, the thoracic organs of the male body
predominate over those of the abdomen, whilst in the female form the ventral
organs take precedence as to development and proportions. This diversity in the
relative capacity of the thorax and abdomen at different stages of development,
and also in persons of different sexes, stamps each individual with
characteristic traits of physical conformation; and it is required that we
should take into our consideration this normal diversity of character, while
conducting our examinations of individuals in reference to the existence of
disease.

The heart varies in some measure, not only as to size and weight, but also as
to position, even in healthy individuals of the same age and sex. The level at
which the heart is in general found to be situated in the thorax is that
represented in PLATE 23, where the apex points to the sixth intercostal space
on the left side above K, while the arch of the aorta rises to a level with C,
the second costal cartilage. In some instances, the heart may be found to
occupy a much lower position in the thorax than the one above mentioned, or
even a much higher level. The impulse of the right ventricle, F, has been
noticed occasionally as corresponding to a point somewhat above the middle of
the sternum and the intercostal space between the fourth and fifth left costal
cartilages; while in other instances its beating was observable as low down as
an inch or more below the xiphoid cartilage, and these variations have existed
in a state of health.

Percussion over the region of the heart yields a dull flat sound. The sound is
dullest opposite the right ventricle, F; whilst above and to either side of
this point, where the heart is overlapped by the anterior shelving edges of
both lungs, the sound is modified in consequence of the lung’s resonant
qualities. The heart-sounds, as heard through the stethoscope, in valvular
disease, will, of course, be more distinctly ascertained at the locality of F,
the right ventricle, which is immediately substernal. While the body lies
supine, the heart recedes from the forepart of the chest; and the lungs during
inspiration expanding around the heart will render its sounds less distinct. In
the erect posture, the heart inclines forwards and approaches the anterior wall
of the thorax. When the heart is hypertrophied, the lungs do not overlap it to
the same extent as when it is of its ordinary size. In the latter state, the
elastic cushion of the lung muffles the heart’s impulse. In the former state,
the lung is pushed aside by the overgrown heart, the strong muscular walls of
which strike forcibly against the ribs and sternum.

The thorax is separated from the abdomen by the moveable diaphragm. The heart,
F E, lies upon the diaphragm, L L*. The liver, M, lies immediately beneath the
right side of this muscular septum, L*, while the bulging cardiac end of the
stomach, O, is in close contact with it on the left side, L. As these three
organs are attached to the diaphragm—the heart by its pericardium, the stomach
by the tube of the oesophagus, and the liver by its suspensory ligaments—it
must happen that the diaphragm while descending and ascending in the motions of
inspiration and expiration will communicate the same alternate motions to the
organs which are connected with it.

In ordinary respiration the capacity of the thorax is chiefly affected by the
motions of the diaphragm; and the relative position which this septum holds
with regard to the thoracic and abdominal chambers will cause its motions of
ascent and descent to influence the capacity of both chambers at the same time.
When the lungs expand, they follow the descent of the diaphragm, which forces
the abdominal contents downwards, and thus what the thorax gains in space the
abdomen loses. When the lungs contract, the diaphragm ascends, and by this act
the abdomen gains that space which the thorax loses. But the organs of the
thoracic cavity perform a different office in the economy from those of the
abdomen. The air which fills the lungs is soon again expired, whilst the
ingesta of the abdominal viscera are for a longer period retained; and as the
space, which by every inspiration the thorax gains from the abdomen, would
cause inconvenient pressure on the distended organs of this latter cavity, so
we find that to obviate this inconvenience, nature has constructed the anterior
parietes of the abdomen of yielding material. The muscular parietes of the
abdomen relax during every inspiration, and thus this cavity gains that space
which it loses by the encroachment of the dilating lungs.

The mechanical principle upon which the abdominal chamber is constructed,
enables it to adjust its capacity to such exigence or pressing necessity as its
own visceral organs impose on it, from time to time; and the relation which the
abdominal cavity bears to the thoracic chamber, enables it also to be
compensatory to this latter. When the inspiratory thorax gains space from the
abdomen, or when space is demanded for the increasing bulk of the alimentary
canal, or for the enlarging pregnant uterus; or when, in consequence of
disease, such as dropsical accumulation, more room is wanted, then the
abdominal chamber supplies the demand by the anterior bulge or swell of its
expansile muscular parietes.

The position of the heart itself is affected by the expansion of the lungs on
either side of it. As the expanding lungs force the diaphragm downwards, the
heart follows it, and all the abdominal viscera yield place to the descending
thoracic contents. In strong muscular efforts the diaphragm plays an important
part, for, previously to making forced efforts, the lungs are distended with
air, so as to swell and render fixed the thoracic walls into which so many
powerful muscles of the shoulders, the neck, back, and abdomen, are inserted;
at the same time the muscular diaphragm L L*, becomes tense and unbent from its
arched form, thereby contracting abdominal space, which now has no compensation
for this loss of space, since the abdominal parietes are also rendered firm and
unyielding. It is at this crisis of muscular effort that the abdominal viscera
become impacted together; and, acting by their own elasticity against the
muscular force, make an exit for themselves through the weakest parts of the
abdominal walls, and thus herniae of various kinds are produced. The most
common situations of abdominal herniae are at the inguinal regions, towards
which the intestines, T T, naturally gravitate; and at these situations the
abdominal parietes are weak and membranous.

The contents of a hernial protrusion through the abdominal parietes, correspond
in general with those divisions of the intestinal tube, which naturally lie
adjacent to the part where the rupture has taken place. In the umbilical hernia
it is either the transverse colon S*, or some part of the small intestine
occupying the median line, or both together, with some folds of the omentum,
which will be found to form the contents of this swelling. When the diaphragm
itself sustains a rupture in its left half, the upper portion of the descending
colon, S, protrudes through the opening. A diaphragmatic hernia has not, so far
as I am aware, been seen to occur in the right side; and this exemption from
rupture of the right half of the diaphragm may be accounted for anatomically,
by the fact that the liver, M, defends the diaphragm at this situation. The
liver occupies the whole depth of the right hypochondrium; and intervenes
between the diaphragm L*, and the right extremity of the transverse colon, S**.

The contents of a right inguinal hernia consist of the small intestine, T. The
contents of the right crural hernia are formed by either the small intestine,
T, or the intestinum caecum, S***. I have seen a few cases in which the caecum
formed the right crural hernia. Examples are recorded in which the intestine
caecum formed the contents of a right inguinal hernia. The left inguinal and
crural herniae contain most generally the small intestine, T, of the left side.

The right lung, I*, is shorter than the left; for the liver, M, raises the
diaphragm, L, to a higher level within the thorax, on the right side, than it
does on the left. When the liver happens to be diseased and enlarged, it
encroaches still more on thoracic space; but, doubtless, judging from the
anatomical connexions of the liver, we may conclude that when it becomes
increased in volume it will accommodate itself as much at the expense of
abdominal space. The liver, in its healthy state and normal proportions,
protrudes for an inch (more or less) below the margins of the right asternal
ribs. The upper or convex surface of the liver rises beneath the diaphragm to a
level corresponding with the seventh or sixth rib, but this position will vary
according to the descent and ascent of the diaphragm in the respiratory
movements. The ligaments by which the liver is suspended do not prevent its
full obedience to these motions.

The left lung, I, descends to a lower level than the right; and the left
diaphragm upon which it rests is itself supported by the cardiac end of the
stomach. When the stomach is distended, it does not even then materially
obstruct the expansion of the left lung, or the descent of the left diaphragm,
for the abdominal walls relax and allow of the increasing volume of the stomach
to accommodate itself. The spleen, R, is occasionally subject to an
extraordinary increase of bulk; and this organ, like the enlarged liver and the
distended stomach, will, to some extent, obstruct the movements of the
diaphragm in the act of respiration, but owing to its free attachments it
admits of a change of place. The abdominal viscera, one and all, admit of a
change of place; the peculiar forms of those mesenteric bonds by which they are
suspended, allow them to glide freely over each other; and this circumstance,
together with the yielding nature of the abdominal parietes, allows the
thoracic organs to have full and easy play in the respiratory movements
performed by agency of the diaphragm.

The muscles of respiration perform with ease so long as the air has access to
the lungs through the normal passage, viz., the trachea. While the principle of
the thoracic pneumatic apparatus remains underanged, the motor powers perform
their functions capably. The physical or pneumatic power acts in obedience to
the vital or muscular power, while both stand in equilibrium; but the
ascendancy of the one over the other deranges the whole thoracic machine. When
the glottis closes by muscular spasm and excludes the external air, the
respiratory muscles cease to exert a motor power upon the pulmonary cavity;
their united efforts cannot cause a vacuum in thoracic space in opposition to
the pressure of the external air. When, in addition to the natural opening of
the glottis, a false opening is made in the side at the point K, the air within
the lung at I, and external to it in the now open pleural cavity, will stand in
equilibrio; the lung will collapse as having no muscular power by which to
dilate itself, and the thoracic dilator muscles will cease to affect the
capacity of the lung, so long as by their action in expanding the thoracic
walls, the air gains access through the side to the pleural sac external to the
lung.

Whether the air be admitted into the pleural sac, by an opening made in the
side from without, or by an opening in the lung itself, the mechanical
principle of the respiratory apparatus will be equally deranged. Pneumo-thorax
will be the result of either lesion; and by the accumulation of air in the
pleura the lung will suffer pressure. This pressure will be permanent so long
as the air has no egress from the cavity of the pleura.

The permanent distention of the thoracic cavity, caused by the accumulation of
air in the pleural sac, or by the diffusion of air through the interlobular
cellular tissue consequent on a wound of the lung itself, will equally obstruct
the breathing; and though the situation of the accumulated air is in fact
anatomically different in both cases, yet the effect produced is similar.
Interlobular pressure and interpleural pressure result in the same thing, viz.,
the permanent retention of the air external to the pulmonary cells, which, in
the former case, are collapsed individually; and, in the latter case, in the
mass. Though the emphysematous lung is distended to a size equal to the healthy
lung in deep inspiration, yet we know that emphysematous distention, being
produced by extrabronchial air accumulation, is, in fact, obstructive to the
respiratory act. The emphysematous lung will, in the same manner as the
distended pleural sac, depress the diaphragm and render the thoracic muscles
inoperative. The foregoing observations have been made in reference to the
effect of wounds of the thorax, the proper treatment of which will be obviously
suggested by our knowledge of the state of the contained organs which have
suffered lesion.

DESCRIPTION OF PLATE 23.

A. Upper end of the sternum.

B B.* First pair of ribs.

C C.* Second pair of ribs.

D. Aorta, with left vagus and phrenic nerves crossing its transverse arch.

E. Root of pulmonary artery.

F. Right ventricle.

G. Right auricle.

H. Vena cava superior, with right phrenic nerve on its outer border.

I I*. Right and left lungs collapsed, and turned outwards, to show the heart’s
outline.

K K*. Seventh pair of ribs.

L L*. The diaphragm in section.

M. The liver in section.

N. The gall bladder with its duct joining the hepatic duct to form the common
bile duct. The hepatic artery is seen superficial to the common duct; the vena
portae is seen beneath it. The patent orifices of the hepatic veins are seen on
the cut surface of the liver.

O. The stomach.

P. The coeliac axis dividing into the coronary, splenic and hepatic arteries.

Q. Inferior vena cava.

R. The spleen.

S S* S**. The transverse colon, between which and the lower border of seen the
gastro-epiploic artery, formed by the splenic and hepatic arteries.

S***. Ascending colon in the right iliac region.

T. Convolutions of the small intestines distended with air.

Plate 23

COMMENTARY ON PLATE 24.

THE RELATIONS OF THE PRINCIPAL BLOODVESSELS TO THE VISCERA OF THE
THORACICO-ABDOMINAL CAVITY.

The median line of the body is occupied by the centres of the four great
systems of organs which serve in the processes of circulation, respiration,
innervation, and nutrition. These organs being fashioned in accordance with the
law of symmetry, we find them arranged in close connexion with the vertebrate
centre of the osseous fabric, which is itself symmetrical. In this symmetrical
arrangement of the main organs of the trunk of the body, a mechanical principle
is prominently apparent; for as the centre is the least moveable and most
protected region of the form, so have these vitally important structures the
full benefit of this situation. The aortal trunk, G, of the arterial system is
disposed along the median line, as well for its own safety as for the fitting
distribution of those branches which spring symmetrically from either side of
it to supply the lateral regions of the body.

The visceral system of bloodvessels is moulded upon the organs which they
supply. As the thoracic viscera differ in form and functional character from
those of the abdomen, so we find that the arterial branches which are supplied
by the aorta to each set, differ likewise in some degree. In the accompanying
figure, which represents the thoracic and abdominal visceral branches of the
aorta taken in their entirety, this difference in their arrangement may be
readily recognised. In the thorax, compared with the abdomen, we find that not
only do the aortic branches differ in form according to the variety of those
organs contained in either region, but that they differ numerically according
to the number of organs situated in each. The main vessel itself, however, is
common to both regions. It is the one thoracico-abdominal vessel, and this
circumstance calls for the comparison, not only of the several parts of the
great vessel itself, but of all the branches which spring from it, and of the
various organs which lie in its vicinity in the thorax and abdomen, and hence
we are invited to the study of these regions themselves connectedly.

In the thorax, the aorta, G G*, is wholly concealed by the lungs in their
states both of inspiration and expiration. The first part of the aortic arch,
as it springs from the left ventricle of the heart, is the most superficial,
being almost immediately sub-sternal, and on a level with the sternal junctions
of the fourth ribs. By applying the ear at this locality, the play of the
aortic valves may be distinctly heard. From this point the aorta, G, rises and
arches from before, backwards, to the left side of the spine, G*. The arch of
the vessel lies more deeply between the two lungs than does its ventricular
origin. The descending thoracic aorta lies still more deeply situated at the
left side of the dorsal spine. At this latter situation it is in immediate
contact with the posterior thick part of the left lung; whilst on its right are
placed, L, the thoracic duct; I, the oesophagus; K, the vena azygos, and the
vertebral column. In Plate 26 may be seen the relation which the superior vena
cava, H, bears to the aortic arch, A.

In the span of the aortic arch will be found, H*, the left bronchus, together
with the right branch of the pulmonary artery, and the right pulmonary veins.
The pneumo-gastric and phrenic nerves descend on either side of the arch. The
left pneumo-gastric nerve winds round beneath the arch at the point where the
obliterated ductus arteriosus joins it. See Plates 12 & 26.

The pulmonary artery, B, Plates 1 & 2, lies close upon the fore part, and
conceals the origin, of the systemic aorta. Whenever, therefore, the semilunar
valves of either the pulmonary artery or the systemic aorta become diseased, it
must be extremely difficult to distinguish by the sounds alone, during life, in
which of the two the derangement exists. The origins of both vessels being at
the fore part of the chest, it is in this situation, of course, that the state
of their valves is to be examined. The descending part of the thoracic aorta,
G*, being at the posterior part of the chest, and lying on the vertebral ends
of the left thoracic ribs, will therefore require that we should examine its
condition in the living body at the dorsal aspect of the thorax. As the arch of
the aorta is directed from before backwards—that is, from the sternum to the
spine, it follows that when an aneurism implicates this region of the vessel,
the exact situation of the tumour must be determined by antero-posterior
examination; and we should recollect, that though on the fore part of the chest
the cartilages of the second ribs, where these join the sternum, mark the level
of the aortic arch, on the back of the chest its level is to be taken from the
vertebral ends of the third or fourth ribs. This difference is caused by the
oblique descent of the ribs from the spine to the sternum. The first and second
dorsal vertebrae, with which the first and second ribs articulate, are
considerably above the level of the first and second pieces of the sternum.

In a practical point of view, the pulmonary artery possesses but small interest
for us; and in truth the trunk of the systemic aorta itself may be regarded in
the same disheartening consideration, forasmuch as when serious disease attacks
either vessel, the “tree of life” may be said to be lopped at its root.

When an aneurism arises from the aortic arch it implicates those important
organs which are gathered together in contact with itself. The aneurismal
tumour may press upon and obstruct the bronchi, H H*; the thoracic duct, L; the
oesophagus, I; the superior vena cava, H, Plate 26, or wholly obliterate either
of the vagi nerves. The aneurism of the arch of the aorta may cause suffocation
in two ways—viz., either by pressing directly on the tracheal tube, or by
compressing and irritating the vagus nerve, whose recurrent branch will convey
the stimulus to the laryngeal muscles, and cause spasmodic closure of the
glottis. This anatomical fact also fully accounts for the constant cough which
attends some forms of aortic aneurism. The pulmonary arteries and veins are
also liable to obstruction from the tumour. This will occur the more certainly
if the aneurism spring from the right or the inferior side of the arch, and if
the tumour should not break at an early period, slow absorption, caused by
pressure of the tumour, may destroy even the vertebral column, and endanger the
spinal nervous centre. If the tumour spring from the left side or the fore part
of the arch, it may in time force a passage through the anterior wall of the
thorax.

The principal branches of the thoracic aorta spring from the upper part of its
arch. The innominate artery, 2, is the first to arise from it; the left common
carotid, 6, and the left subclavian artery, 5, spring in succession. These
vessels being destined for the head and upper limbs, we find that the remaining
branches of the thoracic aorta are comparatively diminutive, and of little
surgical interest. The intercostal arteries occasionally, when wounded, call
for the aid of the surgeon; these arteries, like all other branches of the
aorta, are largest at their origin. Where these vessels spring from G, the
descending thoracic aorta, they present considerable caliber; but at this
inaccessible situation, they seldom or never call for surgical interference. As
the intercostal arteries pass outwards, traversing the intercostal spaces with
their accompanying nerves, they diminish in size. Each vessel divides at a
distance of about two inches, more or less, from the spine; and the upper
larger branch lies under cover of the inferior border of the adjacent rib. When
it is required to perform the operation of paracentesis thoracis, this
distribution of the vessel should be borne in mind; and also, that the farther
from the spine this operation is performed, the less in size will the vessels
be found. The intercostal artery is sometimes wounded by the fractured end of
the rib, in which case, if the pleura be lacerated, an effusion of blood takes
place within the thorax, compresses the lung, and obstructs respiration.

The thoracic aorta descends along the left side of the spine, as far as the
last dorsal vertebra, at which situation the pillars of the diaphragm overarch
the vessel. From this place the aorta passes obliquely in front of the five
lumbar vertebrae, and on arriving opposite the fourth, it divides into the two
common iliac branches. The aorta, for an extent included between these latter
boundaries, is named the abdominal aorta, and from its fore part arise those
branches, which supply the viscera of the abdomen.

The branches which spring from the abdominal aorta to supply the viscera of
this region, are considerable, both as to their number and size. They are,
however, of comparatively little interest in practice. To the anatomist they
present many peculiarities of distribution and form worthy of notice, as, for
example, their frequent anastomosis, their looping arrangement, and their large
size and number compared with the actual bulk of the organs which they supply.
As to this latter peculiarity, we interpret it according to the fact that here
the vessels serve other purposes in the economy besides that of the support and
repair of structure. The vessels are large in proportion to the great quantity
of fluid matter secreted from the whole extent of the inner surface of this
glandular apparatus—the gastro-intestinal canal, the liver, pancreas, and
kidneys.

As anatomists, we are enabled, from a knowledge of the relative position of the
various organs and bloodvessels of both the thorax and abdomen, to account for
certain pathological phenomena which, as practitioners, we possess as yet but
little skill to remedy. Thus it would appear most probable that many cases of
anasarca of the lower limbs, and of dropsy of the belly, are frequently caused
by diseased growths of the liver, P, obstructing the inferior vena cava, R, and
vena portae, rather than by what we are taught to be the “want of balance
between secreting and absorbing surfaces.” The like occurrence may obstruct the
gall-ducts, and occasion jaundice. Over-distention of any of those organs
situated beneath the right hypochondrium, will obstruct neighbouring organs and
vessels. Mechanical obstruction is doubtless so frequent a source of
derangement, that we need not on many occasions essay a deeper search for
explaining the mystery of disease.

In the right hypochondriac region there exists a greater variety of organs than
in the left; and disease is also more frequent on the right side. Affections of
the liver will consequently implicate a greater number of organs than
affections of the spleen on the left side, for the spleen is comparatively
isolated from the more important blood vessels and other organs.

The external surface of the liver, P, lies in contact with the diaphragm, N,
the costal cartilages, M, and the upper and lateral parts of the abdominal
parietes; and when the liver becomes the seat of abscess, this, according to
its situation, will point and burst either into the thorax above, or through
the side between or beneath the false ribs, M. The hepatic abscess has been
known to discharge itself through the stomach, the duodenum, T, and the
transverse colon, facts which are readily explained on seeing the close
relationship which these parts hold to the under surface of the liver. When the
liver is inflamed, we account for the gastric irritation, either from the
inflammation having extended to the neighbouring stomach, or by this latter
organ being affected by “reflex action.” The hepatic cough is caused by the
like phenomena disturbing the diaphragm, N, with which the liver, P, lies in
close contact.

When large biliary concretions form in S, the gallbladder, or in the hepatic
duct, Nature, failing in her efforts to discharge them through the common
bile-duct, into the duodenum, T, sets up inflammation and ulcerative
absorption, by aid of which processes they make a passage for themselves
through some adjacent part of the intestine, either the duodenum or the
transverse colon. In these processes the gall-bladder, which contains the
calculus, becomes soldered by effused lymph to the neighbouring part of the
intestinal tube, into which the stone is to be discharged, and thus its escape
into the peritoneal sac is prevented. When the hepatic abscess points
externally towards M, the like process isolates the matter from the cavities of
the chest and abdomen.

In wounds of any part of the intestine, whether of X, the caecum, W, the
sigmoid flexure of the colon, or Z, the small bowel, if sufficient time be
allowed for Nature to establish the adhesive inflammation, she does so, and
thus fortifies the peritoneal sac against an escape of the intestinal matter
into it by soldering the orifice of the wounded intestine to the external
opening. In this mode is formed the artificial anus. The surgeon on principle
aids Nature in attaining this result.

DESCRIPTION OF PLATE 24.

A. The thyroid body.

B. The trachea.

C C*. The first ribs.

D D*. The clavicles, cut at their middle.

E. Humeral part of the great pectoral muscle, cut.

F. The coracoid process of the scapula.

G. The arch of the aorta. G*. Descending aorta in the thorax.

H. Right bronchus. H*. Left bronchus.

I. Oesophagus.

K. Vena azygos receiving the intercostal veins.

L. Thoracic duct.

M M*. Seventh ribs.

N N. The diaphragm, in section.

O. The cardiac orifice of the stomach.

P. The liver, in section, showing the patent orifices of the hepatic veins.

Q. The coeliac axis sending off branches to the liver, stomach, and spleen. The
stomach has been removed, to show the looping anastomosis of these vessels
around the superior and inferior borders of the stomach.

R. The inferior vena cava about to enter its notch in the posterior thick part
of the liver, to receive the hepatic veins.

S. The gall-bladder, communicating by its duct with the hepatic duct, which is
lying upon the vena portae, and by the side of the hepatic artery.

T. The pyloric end of the stomach, joining T*, the duodenum.

U. The spleen.

V V. The pancreas.

W. The sigmoid flexure of the colon.

X. The caput coli.

Y. The mesentery supporting the numerous looping branches of the superior
mesenteric artery.

Z. Some coils of the small intestine.

2. Innominate artery.

3. Right subclavian artery.

4. Right common carotid artery.

5. Left subclavian artery.

6. Left common carotid artery.

7. Left axillary artery.

8. Coracoid attachment of the smaller pectoral muscle.

9. Subscapular muscle.

10. Coracoid head of the biceps muscle.

11. Tendon of the latissimus dorsi muscle.

12. Superior mesenteric artery, with its accompanying vein.

13. Left kidney.

Plate 24

COMMENTARY ON PLATE 25.

THE RELATION OF THE PRINCIPAL BLOODVESSELS OF THE THORAX AND ABDOMEN TO THE
OSSEOUS SKELETON, ETC.

The arterial system of vessels assumes, in all cases, somewhat of the character
of the forms upon which they are distributed, or of the organs which they
supply. This mode of distribution becomes the more apparent, according as we
rise from particulars to take a view of the whole. With the same ease
that any piece of the osseous fabric, taken separately, may be known, so may
any one artery, taken apart from the rest, be distinguished as to the place
which it occupied, and the organs which it supplied in the economy. The
vascular skeleton, whether taken as a whole or in parts, exhibits
characteristics as apparent as are those of the osseous skeleton itself. The
main bloodvessel, A B C, of the trunk of the body, possesses character, sui
generis, just as the vertebral column itself manifests. The main arteries
of the head or limbs are as readily distinguishable, the one from the other, as
are the osseous fabrics of the head and limbs. The visceral arteries are
likewise moulded upon the forms which they supply. But evidently the arterial
system of vessels conforms most strictly with the general design of the osseous
skeleton.

In Plate 25, viewed as a whole, we find that as the vertebral column stands
central to the osseous skeleton, so does the aorta, A B C, take the centre of
the arterial skeleton. As the ribs jut symmetrically from either side of the
vertebral column, so do the intercostal arteries follow them from their own
points of origin in the aorta. The one side of the osseous system is not more
like the other than is the system of vessels on one side like that of the
other. And in addition to this fact of a similarity of sides in the vascular as
in the osseous skeleton, I also remark that both extremities of the aorta
divide into branches which are similar to one another above and below, thereby
conforming exactly with the upper and lower limbs, which manifest unmistakable
points of analogy.

The branches which spring from the aortic arch above are destined to supply the
head and upper limbs. They are, H, the innominate artery, and I K, the left
common carotid and subclavian arteries. The branches which spring from the
other extremity of the aorta are disposed for the support of the pelvis and
lower limbs; they are the right and left common iliac arteries, L M. These
vessels exhibit, at both ends of the main aortic trunk, a remarkable analogy;
and as the knowledge of this fact may serve to lighten the dry and weary detail
of descriptive anatomy, at the same time that it points directly to views of
practical import, I may be allowed briefly to remark upon it as follows:—

The vessels which spring from both ends of the aorta, as seen in Plate 25, are
represented in what is called their normal character—that is, while three
vessels, H I K, spring separately from the aortic arch above, only two vessels,
L and M, arise from the aorta below. Let the anatomist now recall to mind the
“peculiarities” which at times appear amongst the vessels, H I K, above, and he
will find that some of them absolutely correspond to the normal arrangement of
the vessels, L M, below. And if he will consider the “peculiarities” which
occur to the normal order of the vessels, L M, below, he will find that some of
these correspond exactly to the normal order of the vessels above. Thus, when I
K of the left side join into a common trunk, this resembles the innominate
artery, H, of the right side, and then both these vessels perfectly correspond
with the two common iliac arteries below. When, on the other hand, L and M, the
common iliac arteries, divide, immediately after leaving the aortic trunk, into
two pairs of branches, they correspond to the abnormal condition of the
vessels, H I K, above; where H, immediately after leaving the aortic arch,
divides into two branches, like I K. With this generalization upon the normal
and abnormal facts of arrangement, exhibited among the vessels arising from
both ends of the aorta, I furnish to the reader the idea that the vessels, H I
K, above may present of the same figure as the vessels, L M, below, and these
latter may assume the character of H I K, above. Whenever, therefore, either
set of vessels becomes the subject of operation, such as having a ligature
applied to them, we must be prepared to meet the “varieties.”

The veins assume an arrangement similar to that of the arteries, and the above
remarks will therefore equally apply to the veins. In the same way as the
arteries, H I K, may present in the condition of two common or brachio-cephalic
trunks, and thereby simulate the condition of the common iliac arteries, so we
find that the normal forms of the veins above and below actually and
permanently exhibit this very type. The brachio-cephalic veins, D B, Plate 26,
exactly correspond to each other, and to the common iliac veins, S T; and as
these latter correspond precisely with the common iliac arteries, so may we
infer that the original or typical condition of the vessels I K, Plate 25, is a
brachia-cephalic or common-trunk union corresponding with its brachio-cephalic
vein. When the vessels, I K, therefore present of the brachio-cephalic form as
the vessel H, we have a perfect correspondence between the two extremes of the
aorta, both as regards the arteries arising from it, and the veins which
accompany these arteries; and this condition of the vascular skeleton I regard
as the typical uniformity. The separate condition of the vessels I K,
notwithstanding the frequency of the occurrence of such, may be considered as a
special variation from the original type.

The length of the aorta is variable in two or more bodies; and so, likewise, is
the length of the trunk of each of those great branches which springs from its
arch above, and of those into which it divides below, The modes in which these
variations as to length occur, are numerous. The top of the arch of the aorta
is described as being in general on a level with the cartilages of the second
ribs, from which point it descends on the left side of the spinal column; and
after having wound gradually forwards to the forepart of the lumbar spine at C,
divides opposite to the fourth lumbar vertebra into the right and left common
iliac arteries. The length of that portion of the aorta which is called
thoracic, is determined by the position of the pillars of the diaphragm F,
which span the vessel; and from this point to where the aorta divides into the
two common iliac arteries, the main vessel is named abdominal. The aorta, from
its arch to its point of division on the lumbar vertebrae, gradually diminishes
in caliber, according to the number and succession of the branches derived from
it.

The varieties as to length exhibited by the aorta itself, and by the principal
branches which spring from it, occur under the following mentioned
conditions:—When the arch of the aorta rises above or sinks below its ordinary
position or level,—namely, the cartilages of the second ribs, as seen in Plate
25,—it varies not only its own length, but also that of the vessels H I K; for
if the arch of the aorta rises above this level, the vessels H I K become
shortened; and as the arch sinks below this level, these vessels become
lengthened. Even when the aortic arch holds its proper level in the thorax,
still the vessels H I K may vary as to length, according to the height to which
they rise in the neck previously to their division. When the aorta sinks below
its proper level at the same time that the vessels H I K rise considerably
above that point at which they usually arch or divide in the neck, then of
course their length becomes greatly increased. When, on the other hand, the
aortic arch rises above its usual level, whilst the vessels H I K arch and
divide at a low position in the neck, then their length becomes very much
diminished. The length of the artery H may be increased even though the arch of
the aorta holds its proper level, and though the vessels H I K occupy their
usual position in the neck; for it is true that the vessel H may spring from a
point of the aortic arch A nearer to the origin of this from the ventricle of
the heart, whilst the vessel I may be shortened, owing to the fact of its
arising from some part of H, the innominate vessel. All these circumstances are
so obvious, that they need no comment, were it not for the necessity of
impressing the surgeon with the fact that uncertainty as to a successful result
must always attach to his operation of including in a ligature either of the
vessels H I K, so as to affect an aneurismal tumour.

Now whilst the length of the aorta and that of the principal branches springing
from its arch may be varied according to the above-mentioned conditions, so may
the length of the aorta itself, and of the two common iliac vessels, vary
according to the place whereat the aorta, C, bifurcates. Or, even when this
point of division is opposite the usual vertebra,—viz., the fourth
lumbar,—still the common iliac vessels may be short or long, according to the
place where they divide into external and internal iliac branches. The aorta
may bifurcate almost as high up as where the pillars of the diaphragm overarch
it, or as low down as the fifth lumbar vertebra. The occasional existence of a
sixth lumbar vertebra also causes a variety in the length, not only of the
aorta, but of the two common iliac vessels and their branches.[Footnote]

[Footnote: Whatever may be the number of variations to which the branches
arising from both extremes of the aorta are liable, all anatomists admit that
the arrangement of these vessels, as exhibited in Plate 25, is by far the most
frequent. The surgical anatomist, therefore, when planning his operation, takes
this arrangement as the standard type. Haller asserts this order of the vessels
to be so constant, that in four hundred bodies which he examined, he found only
one variety—namely, that in which the left vertebral artery arose from
the aorta. Of other varieties described by authors, he observes—“Rara vero haec
omnia esse si dixero cum quadringenta nunc cadavera humana dissecuerim, fidem
forte inveniam.” (Iconum Anatom.) This variety is also stated by J. F. Meckel
(Handbuch der Mensch Anat.), Soemmerring (De Corp. Hum Fabrica), Boyer (Tr.
d’Anat.), and Mr. Harrison (Surg. Anal. of Art.), to be the most frequent.
Tiedemann figures this variety amongst others (Tabulae Arteriarum). Mr. Quain
regards as the most frequent change which occurs in the number of the branches
of the aortic arch, “that in which the left carotid is derived from the
innominate.” (Anatomy of the Arteries, &c.) A case is recorded by Petsche
(quoted in Haller), in which he states the bifurcation of the aorta to have
taken place at the origin of the renal arteries: (query) are we to suppose that
the renal arteries occupied their usual position? Cruveilhier records a case
(Anal. Descript.) in which the right common iliac was wanting, in consequence
of having divided at the aorta into the internal and external iliac branches.
Whether the knowledge of these and numerous other varieties of the arterial
system be of much practical import to the surgeon, he will determine for
himself. To the scientific anatomist, it must appear that the main object in
regard to them is to submit them to a strict analogical reasoning, so as to
demonstrate the operation of that law which has produced them. To this end I
have pointed to that analogy which exists between the vessels arising from both
extremities of the aorta. “Itaque convertenda plane est opera ad inquirendas et
notandas rerum similitudines et analoga tam integralibus quam partibus; illae
enim sunt, quae naturam uniunt, et constituere scientias incipiunt.” “Natura
enim non nisi parendo vincitur; et quod in contemplatione instar causae est; id
in operatione instar regulae est.” (Novum Organum Scientiarum, Aph. xxvii-iii,
lib. i.)]

The difference between the perpendicular range of the anterior and posterior
walls of the thoracic cavity may be estimated on a reference to Plate 25, in
which the xyphoid cartilage, E, joined to the seventh pair of ribs, bounds its
anterior wall below, while F, the pillars of the diaphragm, bound its posterior
wall. The thoracic cavity is therefore considerably deeper in its posterior
than in its anterior wall; and this occasions a difference of an opposite kind
in the anterior and posterior walls of the abdomen; for while the abdomen
ranges perpendicularly from E to W, its posterior range measures only from F to
the ventra of the iliac bones, R. The arching form of the diaphragm, and the
lower level which the pubic symphysis occupies compared with that of the
cristae of the iliac bones, occasion this difference in the measure of both the
thorax and abdomen.

The usual position of the kidneys, G G*, is on either side of the lumbar spine,
between the last ribs and the cristae of the iliac bones. The kidneys lie on
the fore part of the quadratus lumborum and psoae muscles. They are sometimes
found to have descended as low as the iliac fossae, R, in consequence of
pressure, occasioned by an enlarged liver on the right, or by an enlarged
spleen on the left. The length of the abdominal part of the aorta may be
estimated as being a third of the entire vessel, measured from the top of its
arch to its point of bifurcation. So many and such large vessels arise from the
abdominal part of the aorta, and these are set so closely to each other, that
it must in all cases be very difficult to choose a proper locality whereat to
apply a ligature on this region of the vessel. If other circumstances could
fairly justify such an operation, the anatomist believes that the circulation
might be maintained through the anastomosis of the internal mammary and
intercostal arteries with the epigastric; the branches of the superior
mesenteric with those of the inferior; and the branches of this latter with the
perineal branches of the pubic. The lumbar, the gluteal, and the circumflex
ilii arteries, also communicate around the hip-bone. The same vessels would
serve to carryon the circulation if either L, the common iliac, V, the external
iliac, or the internal iliac vessel, were the subject of the operation by
ligature.

DESCRIPTION OF PLATE 25.

A. The arch of the aorta.

B B. The descending thoracic part of the aorta, giving off b b, the
intercostal arteries.

C. The abdominal part of the aorta.

D D. First pair of ribs.

E. The xyphoid cartilage.

G G*. The right and left kidneys.

H. The brachio-cephalic artery.

I. Left common carotid artery.

K. Left subclavian artery.

L. Right common iliac artery at its place of division.

M. Left common iliac artery, seen through the meso-rectum.

N. Inferior vena cava.

O O. The sigmoid flexure of the colon.

P. The rectum.

Q. The urinary bladder.

R. The right iliac fossa.

S S. The right and left ureters.

T. The left common iliac vein, joining the right under the right common iliac
artery to form the inferior vena cava.

U. Fifth lumbar vertebra.

V. The external iliac artery of right side.

W. The symphysis pubis.

X. An incision made over the locality of the femoral artery.

b b. The dorsal intercostal arteries.

c. The coeliac axis

d. The superior mesenteric artery.

f f. The renal arteries.

g. The inferior mesenteric artery.

h. The vas deferens bending over the epigastric artery and the os pubis,
after having passed through the internal abdominal ring.

Plate 25

COMMENTARY ON PLATE 26.

THE RELATION OF THE INTERNAL PARTS TO THE EXTERNAL SURFACE OF THE BODY.

An exact acquaintance with the normal character of the external form, its
natural prominences and depressions, produced by the projecting swell of
muscles and points of bone, &c., is of great practical importance to the
surgeon. These several marks described on the superficies he takes as certain
guides to the precise locality and relations of the more deeply situated
organs. And as, by dissection, Nature reveals to him the fact that she holds
constant to these relations, so, at least, may all that department of practice
which he bases upon this anatomical certainty be accounted as rooted in truth
and governed by fixed principles. The same organ bears the same special and
general relations in all bodies, not only of the human, but of all other
species of vertebrata; and from this evidence we conclude that the same marks
on surface indicate the exact situation of the same organs in all similar
bodies.

The surface of the well-formed human body presents to our observation certain
standard characters with which we compare all its abnormal conditions. Every
region of the body exhibits fixed character proper to its surface. The neck,
the axilla, the thorax, the abdomen, the groin, have each their special marks,
by which we know them; and the eye, well versed in the characters proper to the
healthy state of each, will soonest discover the nature of all effects of
injury—such as dislocations, fractures, tumours of various kinds, &c. By
our acquaintance with the perfect, we discover the imperfect; by a comparison
with the geometrically true rectangled triangle, or circle, we estimate the
error of these forms when they have become distorted; and in the same way, by a
knowledge of what is the healthy normal standard of human form, we diagnose
correctly its slightest degree of deformity, produced by any cause whatever,
whether by sudden accident, or slowly-approaching disease.

Now, the abnormal conditions of the surface become at once apparent to our
senses; but those diseased conditions which concern the internal organs require
no ordinary exercise of judgment to discover them. The outward form masks the
internal parts, and conceals from our direct view, like the covers of a closed
volume, the marvellous history contained within. But still the superficies is
so moulded upon the deeper situated structures, that we are induced to study it
as a map, which discourses of all which it incloses in the healthy or the
diseased state. Thus, the sternum points to A, the aorta; the middle of the
clavicles, to C, the subclavian vessels; the localities 9, 10 of the coracoid
processes indicate the place of the axillary vessels; the navel, P, points to
Q, the bifurcation of the aorta; the pubic symphysis, Z, directs to the urinary
bladder, Y. At the points 7, 8, may be felt the anterior superior spinous
processes of the iliac bones, between which points and Z, the iliac vessels, V,
6, pass midway to the thigh, and give off the epigastric vessels, 2, 3, to the
abdominal parietes. Between these points of general relations, which we trace
on the surface of the trunk of the body, the anatomist includes the entire
history of the special relations of the organs within contained. And not until
he is capable of summing together the whole picture of anatomical analysis, and
of viewing this in all its intricate relationary combination—even through and
beneath the closed surface of living moving nature, is he prepared to estimate
the conditions of disease, or interfere for its removal.

When fluid accumulates on either side of the thoracic compartment to such an
excess that an opening is required to be made for its exit from the body, the
operator, who is best acquainted with the relations of the parts in a state of
health, is enabled to judge with most correctness in how far these parts, when
in a state of disease, have swerved from these proper relations. In the normal
state of the thoracic viscera, the left thoracic space, G A K N, is occupied by
the heart and left lung. The space indicated within the points A N K, in the
anterior region of the thorax, is occupied by the heart, which, however, is
partially overlapped by the anterior edge of the lung, PLATE 22. If the thorax
be deeply penetrated at any part of this region, the instrument will wound
either the lung or the heart, according to the situation of the wound. But when
fluid becomes effused in any considerable quantity within the pleural sac, it
occupies space between the lung and the thoracic walls; and the fluid
compresses the lung, or displaces the heart from the left side towards the
right. This displacement may take place to such an extent, that the heart,
instead of occupying the left thoracic angle, A K N, assumes the position of A
K* N on the right side. Therefore, as the fluid, whatever be its quantity,
intervenes between the thoracic walls, K K*, and the compressed lung, the
operation of paracentesis thoracis should be performed at the point K, or
between K and the latissimus dorsi muscle, so as to avoid any possibility of
wounding the heart. The intercostal artery at K is not of any considerable
size.

In the normal state of the thoracic organs, the pericardial envelope of the
heart is at all times more or less uncovered by the anterior edge of the left
lung, as seen in PLATE 22. When serous or other fluid accumulates to an excess
in the pericardium, so as considerably to distend this sac, it must happen that
a greater area of pericardial surface will be exposed and brought into
immediate contact with the thoracic walls on the left side of the sternal
median line, to the exclusion of the left lung, which now no longer interposes
between the heart and the thorax. At this locality, therefore, a puncture may
be made through the thoracic walls, directly into the distended pericardium,
for the escape of its fluid contents, if such proceeding be in other respects
deemed prudent and advisable.

The abdominal cavity being very frequently the seat of dropsical effusion, when
this takes place to any great extent, despite the continued and free use of the
medicinal diuretic and the hydragogue cathartic, the surgeon is required to
make an opening with the instrumental hydragogue—viz., the trocar and cannula.
The proper locality whereat the puncture is to be made so as to avoid any large
bloodvessel or other important organ, is at the middle third of the median
line, between P the umbilicus, and Z the symphysis pubis. The anatomist chooses
this median line as the safest place in which to perform paracentesis
abdominis, well knowing the situation of 2, 3, the epigastric vessels, and of
Y, the urinary bladder.

All kinds of fluid occupying the cavities of the body gravitate towards the
most depending part; and therefore, as in the sitting or standing posture, the
fluid of ascites falls upon the line P Z, the propriety of giving the patient
this position, and of choosing some point within the line P Z, for the place
whereat to make the opening, becomes obvious. In the female, the ovary is
frequently the seat of dropsical accumulation to such an extent as to distend
the abdomen very considerably. Ovarian dropsy is distinguished from ascites by
the particular form and situation of the swelling. In ascites, the abdominal
swell is symmetrical, when the body stands or sits erect. In ovarian dropsy,
the tumour is greatest on either side of the median line, according as the
affected ovary happens to be the right or the left one.

The fluid of ascites and that of the ovarian dropsy affect the position of the
abdominal viscera variously In ascites, the fluid gravitates to whichever side
the body inclines, and it displaces the moveable viscera towards the opposite
side. Therefore, to whichever side the abdominal fluid gravitates, we may
expect to find it occupying space between the abdominal parietes and the small
intestines. The ovarian tumour is, on the contrary, comparatively fixed to
either side of the abdominal median line; and whether it be the right or left
ovary that is affected, it permanently displaces the intestines on its own
side; and the sac lies in contact with the neighbouring abdominal parietes; nor
will the intestines and it change position according to the line of
gravitation.

Now, though the above-mentioned circumstances be anatomically true respecting
dropsical effusion within the general peritonaeal sac and that of the ovary,
there are many urgent reasons for preferring to all other localities the line P
Z, as the only proper one for puncturing the abdomen so as to give exit to the
fluid. For though the peritonaeal ascites does, according to the position of
the patient, gravitate to either side of the abdomen, and displace the moveable
viscera on that side, we should recollect that some of these are bound fixedly
to one place, and cannot be floated aside by the gravitating fluid. The liver
is fixed to the right side, 11, by its suspensory ligaments. The spleen
occupies the left side, 12. The caecum and the sigmoid flexure of the colon
occupy, R R*, the right and left iliac regions. The colon ranges transversely
across the abdomen, at P. The stomach lies transversely between the points, 11,
12. The kidneys, O, occupy the lumbar region. All these organs continue to hold
their proper places, to whatever extent the dropsical effusion may take place,
and notwithstanding the various inclinations of the body in this or that
direction. On this account, therefore, we avoid performing the operation of
paracentesis abdominis at any part except the median line, P Z; and as to this
place, we prefer it to all others, for the following cogent reasons—viz., the
absence of any large artery; the absence of any important viscus; the fact that
the contained fluid gravitates in large quantity, and in immediate contact with
the abdominal walls anteriorly, and interposes itself between these walls and
the small intestines, which float free, and cannot approach the parietes of the
abdomen nearer than the length which the mesenteric bond allows.

If the ovarian dropsy form a considerable tumour in the abdomen, it may be
readily reached by the trocar and cannula penetrating the line P Z. And thus we
avoid the situation of the epigastric vessels. The puncture through the linea
alba should never be made below the point, midway between P and Z, lest we
wound the urinary bladder, which, when distended, rises considerably above the
pubic symphysis.

Amongst the many mechanical obstructions which, by impeding the circulation,
give rise to dropsical effusion, are the following:—An aneurismal tumour of the
aorta, A, or the innominate artery, [Footnote 1] F, may press upon the veins, H
or D, and cause an oedematous swelling of the corresponding side of the face
and the right arm. In the same way an aneurism of the aorta, Q, by pressing
upon the inferior vena cava, T, may cause oedema of the lower limbs. Serum may
accumulate in the pericardium, owing to an obstruction of the cardiac veins,
caused by hypertrophy of the substance of the heart; and when from this cause
the pericardium becomes much distended with fluid, the pressure of this upon
the flaccid auricles and large venous trunks may give rise to general anasarca,
to hydrothorax or ascites, either separate or co-existing. Tuberculous deposits
in the lungs and scrofulous bronchial glands may cause obstructive pressure on
the pulmonary veins, followed by effusion of either pus or serum into the
pleural sac. [Footnote 2] An abscess or other tumour of the liver may, by
pressing on the vena portae, cause serous effusion into the peritonaeal sac; or
by pressure on the inferior vena cava, which is connected with the posterior
thick border of the liver, may cause anasarca of the lower limbs. Matter
accumulating habitually in the sigmoid flexure of the colon may cause a
hydrocele, or a varicocele, by pressing on the spermatic veins of the left
side. It is quite true that these two last-named affections appear more
frequently on the left side than on the right; and it seems to me much more
rational to attribute them to the above-mentioned circumstance than to the fact
that the left spermatic veins open, at a disadvantageous right angle, into the
left renal vein.

[Footnote 1: The situation of this vessel, its close relation to the pleura,
the aorta, the large venous trunks, the vagus and phrenic nerves, and the
uncertainty as to its length, or as to whether or not a thyroid or vertebral
branch arises from it, are circumstances which render the operation of tying
the vessel in cases of aneurism very doubtful as to a successful issue. The
operation (so far as I know) has hitherto failed. Anatomical relations, nearly
similar to these, prevent, in like manner, an easy access to the iliac
arteries, and cause the operator much anxiety as to the issue.]

[Footnote 2: The effusion of fluid into the pleural sac (from whatever cause it
may arise) sometimes takes place to a very remarkable extent. I have had
opportunities of examining patients, in whom the heart appeared to be
completely dislocated, from the left to the right side, owing to the large
collection of serous fluid in the left pleural sac. The heart’s pulsations
could be felt distinctly under the right nipple. Paracentesis thoracis was
performed at the point indicated in PLATE 26. In these cases, and another
observed at the Hotel Dieu, the heart and lung, in consequence of the extensive
adhesions which they contracted in their abnormal position, did not immediately
resume their proper situation when the fluid was withdrawn from the chest. Nor
is it to be expected that they should ever return to their normal character and
position, when the disease which caused their displacement has been of long
standing.]

DESCRIPTION OF PLATE 26.

A. The systemic aorta. Owing to the body being inclined forwards, the root of
the aorta appears to approach too near the lower boundary (N) of the thorax.

B. The left brachio-cephalic vein.

C. Left subclavian vein.

D. Right brachia-cephalic vein.

E. Left common carotid artery.

F. Brachio-cephalic artery.

G G*. The first pair of ribs.

H. Superior vena cava.

I. Left bronchus.

K K*. Fourth pair of ribs.

L. Descending thoracic aorta.

M. Oesophagus.

N. Epigastrium.

O. Left kidney.

P. Umbilicus.

Q. Abdominal aorta, at its bifurcation.

R R*. Right and left iliac fossae.

S. Left common iliac vein.

T. Inferior vena cava.

U. Psoas muscle, supporting the right spermatic vessels.

V. Left external iliac artery crossed by the left ureter.

W. Right external iliac artery crossed by the right ureter.

X. The rectum.

Y. The urinary bladder, which being fully distended, and viewed from above,
gives it the appearance of being higher than usual above the pubic symphysis.

Z. Pubic symphysis.

2. The left internal abdominal ring complicated with the epigastric vessels,
the vas deferens, and the spermatic vessels.

3. The right internal abdominal ring in connection with the like vessels and
duct as that of left side.

4. Superior mesenteric artery.

5, 6. Right and left external iliac veins.

7, 8. Situations of the anterior superior iliac spinous processes.

9, 10. Situations of the coracoid processes.

11, 12. Right and left hypochondriac regions.

Plate 26

COMMENTARY ON PLATE 27.

THE SURGICAL DISSECTION OF THE SUPERFICIAL BLOODVESSELS ETC. OF THE
INGUINO-FEMORAL REGION.

Hernial protrusions are very liable to occur at the inguino-femoral region; and
this fact has led the surgeon to study the anatomical relations of this part
with more than ordinary care and patience. So minutely has he dissected every
structure proper to this locality, and so closely has he investigated every
possible condition of it as being the seat of hernial, that the only novelty
which now remains to be sought for is that of a simplification of the facts,
already known to be far too much obscured by an unwieldy nomenclature, and a
useless detail of trifling evidence. And it would seem that nothing can more
directly tend to this simplification, than that of viewing the inguinal and
femoral regions, not separately, but as a relationary whole. For as both
regions are blended together by structures which are common to both, so do the
herniae which are described as being proper to either region, occur in such
close connexion as at times to render it very difficult to distinguish between
them.

The human species is, of all others, most subject to hernial in the groin. The
erect attitude of the human form, and the fact that many of its more powerful
muscular efforts are performed in this posture, cause its more frequent
liability to the accidents called abdominal herniae or ruptures.

The viscera of the abdomen occupy this cavity completely, and indeed they
naturally, at all times, subject the abdominal parietes to a state of constant
pressure, as may be proved by their escape from the abdomen in cases of large
wounds of this region. In the erect posture of the body this pressure is
increased, for the viscera now gravitate and force downwards and forwards
against the abdominal parietes. In addition to this gravitating force, another
power impels the viscera from above downwards—namely, that of the muscles of
the trunk, and the principal agent amongst these is the diaphragm. The lungs,
again, expanding above the diaphragm, add also to the gravitation of the
abdominal contents, and these, under the pressure thus accumulated,
occasionally make an exit for themselves at the groins, which are the weakest
and most depending parts of the abdomen.

Herniae are variously named in accordance with the following
circumstances—viz., the precise locality at which they occur—the size and form
of the tumour—the time of life at which they happen. Sexual peculiarities do
not serve to distinguish herniae, though it is true that the inguinal form, at
the part D F, occurs more commonly in the male, whilst the crural form, at the
opening E, happens more frequently in the female.

The most common forms of herniae happen at those localities where the abdominal
walls are traversed by the bloodvessels on their way to the outstanding organs,
and where, in consequence, the walls of the abdomen have become weakened. It
also happens, that at these very situations the visceral pressure is greatest
whilst the body stands erect. These localities are, A, the umbilicus, a point
characterized as having given passage (in the foetal state) to the umbilical
vessels; D, the place where the spermatic vessels and duct pass from the
abdomen to the testicle; and immediately beneath this, the crural arch, which
gives exit to the crural vessels. Herniae may happen at other localities, such
as at the thyroid aperture, which transmits the thyroid vessels; and at the
greater sacrosciatic notch, through which the gluteal vessels pass; and all
regions of the abdominal walls may give exit to intestinal protrusion in
consequence of malformations, disease, or injury. But as the more frequent
varieties of herniae are those which traverse the localities, A, D, E, and as
these, fortunately, are the most manageable under the care of the surgical
anatomist, we proceed to examine the structures concerned in their occurrence.

A direct opening from within outwards does not exist in the walls of the
abdomen; and anatomy demonstrates to us the fact, that where the spermatic
cord, D F, and the femoral vessels, pass from the abdomen to the external
parts, they carry with them a covering of the several layers of structures,
both muscular and membranous, which they encounter in their passage. The
inguinal and crural forms of herniae which follow the passages made by the
spermatic cord, and the crural vessels, must necessarily carry with them the
like investments, and these are what constitute the coverings of the herniae
themselves.

The groin in its undissected state is marked by certain elevations and
depressions which indicate the general relations of the subcutaneous parts. The
abdomen is separated from the thigh by an undulating grooved line, extending
from C*, the point of the iliac bone, to B, the symphysis pubis This line or
fold of the groin coincides exactly with the situation of that fibrous band of
the external oblique muscle named Poupart’s ligament. From below the middle of
this abdomino-femoral groove, C B, another curved line, D, b, springs,
and courses obliquely, inwards and downwards, between the upper part of the
thigh and the pubis, to terminate in the scrotum. The external border of this
line indicates the course of the spermatic cord, D F, which can be readily felt
beneath the skin. In all subjects, however gross or emaciated they may happen
to be, these two lines are readily distinguishable, and as they bear relations
to the several kinds of rupture taking place in these parts, the surgeon should
consider them with keen regard. A comparison of the two sides of the figure,
PLATE 27, will show that the spermatic cord, D F, and Poupart’s ligament, C B,
determine the shape of the inguino-femoral region. When the integument with the
subcutaneous adipose tissue is removed from the inguino-femoral region, we
expose that common investing membrane called the superficial fascia. This
fascia, a a a, stretches over the lower part of the abdomen and the
upper part of the thigh. It becomes intimately attached to Poupart’s ligament
along the ilio-pubic line, C B; it invests the spermatic cord, as shown at
b, and descends into the scrotum, so as to encase this part. Where this
superficial fascia overlies the saphenous opening, E, of the fascia lata, it
assumes a “cribriform” character, owing to its being pierced by numerous
lymphatic vessels and some veins. As this superficial fascia invests all parts
of the inguino-femoral region, as it forms an envelope for the spermatic cord,
D F, and sheathes over the saphenous opening, E, it must follow of course that
wherever the hernial protrusion takes place in this region, whether at D, or F,
or E, or adjacent parts, this membrane forms the external subcutaneous covering
of the bowel.

There is another circumstance respecting the form and attachments of the
superficial fascia, which, in a pathological point of view, is worthy of
notice—viz., that owing to the fact of its enveloping the scrotum, penis,
spermatic cord, and abdominal parietes, whilst it becomes firmly attached to
Poupart’s ligament along the abdomino-femoral fold, B C, it isolates these
parts, in some degree, from the thigh; and when urine happens to be from any
cause extravasated through this abdominal-scrotal bag of the superficial
fascia, the thighs do not in general participate in the inflammation
superinduced upon such accident.

The spermatic cord, D, emerges from the abdomen and becomes definable through
the fibres of the sheathing tendon of the external oblique muscle, H, at a
point midway between the extremities of the ilio-pubic line or fold. In some
cases, this place, whereat the cord first manifests itself in the groin, lies
nearer the pubic symphysis; but however much it may vary in this particular, we
may safely regard the femoro-pubic fold, D, b, as containing the cord,
and also that the place where this fold meets the iliopubic line, C B, at the
point D, marks the exit of the cord from the abdomen.

The spermatic cord does not actually pierce the sheathing tendon of the
external oblique muscle at the point D, and there does not, in fact, exist
naturally such an opening as the “external abdominal ring,” for the cord
carries with it a production of the tendon of the external oblique muscle, and
this has been named by surgical anatomists the “intercolumnar fascia,”
[Footnote] the “spermatic fascia.” The fibres of this spermatic fascia are seen
at D F, crossing the cord obliquely, and encasing it. This covering of the cord
lies beneath the spermatic envelope formed by, a b, the superficial
fascia; and when a hernial protrusion descends through the cord, both these
investing membranes form the two outermost envelopes for the intestine in its
new and abnormal situation.

[Footnote: On referring to the works of Sir Astley Cooper, Hesselbach, Scarpa,
and, others, I find attempts made to establish a distinction between what is
called the “intercolumnar fascia” and the “spermatic fascia,” and just as if
these were structures separable from each other or from the aponeurotic sheath
of the external oblique muscle. I find, in like manner, in these and other
works, a tediously-laboured account of the superficial fascia, as being
divisible into two layers of membrane, and that this has given rise to
considerable difference of opinion as to whether or not we should regard the
deeper layer as being a production of the fascia lata, ascending from the thigh
to the abdomen, or rather of the membrane of the abdomen descending to the
thigh, &c. These and such like considerations I omit to discuss here; for,
with all proper deference to the high authority of the authors cited, I dare to
maintain, that, in a practical point of view, they arc absolutely of no moment,
and in a purely scientific view, they are, so far as regards the substance of
the truth which they would reveal, wholly beneath the notice of the rational
mind. The practitioner who would arm his judgment with the knowledge of a broad
fact or principle, should not allow his serious attention to be diverted by a
pursuit after any such useless and trifling details, for not only are they
unallied to the stern requirements of surgical skill, but they serve to degrade
it from the rank and roll of the sciences. Whilst operating for the reduction
of inguinal hernia by the “taxis” or the bistoury, who is there that feels
anxiety concerning the origin or the distinctiveness of the “spermatic fascia?”
Or, knowing it to be present, who concerns himself about the better propriety
of naming it “tunica vaginalis communis,” “tunique fibreuse du cordon
spermatique,” “fascia cremasterica,” or “tunica aponeurotica?”]

The close relations which the cord, D F, bears to the saphenous opening, E, of
the fascia lata, should be closely considered, forasmuch as when an oblique
inguinal hernia descends from D to F, it approaches the situation of the
saphenous opening, E, which is the seat of the femoral or crural hernia, and
both varieties of hernia may hence be confounded. But with a moderate degree of
judgment, based upon the habit of referring the anatomy to the surface, such
error may always be avoided. This important subject shall be more fully treated
of further on.

The superficial bloodvessels of the inguino-femoral region are, e e, the
saphenous vein, which, ascending from the inner side of the leg and thigh,
pierces the saphenous opening, E, to unite with the femoral vein. The saphenous
vein, previously to entering the saphenous opening, receives the epigastric
vein, i, the external circumflex ilii vein, h, and another venous
branch, d, coming from the fore part of the thigh. In the living body
the course of the distended saphenous vein may be traced beneath the skin, and
easily avoided in surgical operations upon the parts contained in this region.
Small branches of the femoral artery pierce the fascia lata, and accompany
these superficial veins. Both these orders of vessels are generally divided in
the operation required for the reduction of either the inguinal or the femoral
strangulated hernia; but they are, for the most part, unimportant in size. Some
branches of nerves, such as, k, the external cutaneous, which is given
off from the lumbar nerves, and, f, the middle cutaneous, which is
derived from the crural nerve, pierce the fascia lata, and appear upon the
external side and middle of the thigh.

Numerous lymphatic glands occupy the inguino-femoral region; these can be felt,
lying subcutaneous, even in the undissected state of the parts. These glands
form two principal groups, one of which, c, lies along the middle of the
inguinal fold, C B; the other, G g, lies scattered in the neighbourhood
of the saphenous opening. The former group receive the lymphatic vessels of the
generative organs; and the glands of which it is composed are those which
suppurate in, syphilitic or other affections of these parts.

The general relations which the larger vessels of the inguino-femoral region
bear to each other and to the superficies, may be referred to in PLATE 27, with
practical advantage. The umbilicus, A, indicates pretty generally the level at
which the aorta bifurcates on the forepart of the lumbar vertebrae. In the
erect, and even in the recumbent posture, the aorta may (especially in
emaciated subjects) be felt pulsating under the pressure of the hand; for the
vertebrae bear forward the vessel to a level nearly equal with, C C, the
anterior superior spinous processes of the iliac bones. If a gunshot were to
pass through the abdomen, transversely, from these points, and through B, it
would penetrate the aorta at its bifurcation. The line A B coincides with the
linea alba. The oblique lines, A D, A D,* indicate the course of the iliac
vessels. The point D marks the situation where the spermatic vessels enter the
abdomen; and also where the epigastric artery is given off from the external
iliac. The most convenient line of incision that can be made for reaching the
situation of either of the iliac arteries, is that which ranges from C, the
iliac spine, to D, the point where the spermatic cord enters the abdomen. The
direct line drawn between D and G marks the course of the femoral artery, and
this ranges along the outer border, E, of the saphenous opening.

DESCRIPTION OF PLATE 27.

A. The umbilicus.

B. The upper margin of the pubic symphysis.

C. The anterior superior spine of the left iliac bone. C*, the situation iof
the corresponding part on the right side.

D. The point where, in this subject, the cord manifested itself beneath ithe
fibres of the external oblique muscle. D*, a corresponding part on ithe
opposite side.

E. The saphenous opening in the fascia lata, receiving e, the saphenous
ivein.

F. The lax and pendulous cord, which in this case, overlies the upper ipart of
the saphenous opening.

G. Lymphatic glands lying on the fascia lata in the neighbourhood of the
isaphenous opening.

H. The fleshy part of the external oblique muscle.

a a a. The superficial fascia of the abdomen.

b. The same fascia forming an envelope for the spermatic cord and
iscrotum.

c. Inguinal glands lying near Poupart’s ligament.

d. A common venous trunk, formed by branches from the thigh and abdomen,
iand joining—

e e. The saphenous vein.

f. The middle cutaneous nerve, derived from the anterior crural nerve.

g. Femoral lymphatic glands.

h. Superficial external iliac vein.

i. Superficial epigastric vein.

k. External cutaneous branches of nerves from the lumbar plexus.

Plate 27

COMMENTARY ON PLATES 28 & 29.

THE SURGICAL DISSECTION OF THE FIRST, SECOND, THIRD, AND FOURTH LAYERS OF THE
INGUINAL REGION IN CONNEXION WITH THOSE OF THE THIGH.

The common integument or first layer of the inguino-femoral region being
removed, we expose the superficial fascia constituting the second layer.
The connexion of this fascia with Poupart’s ligament along the line C D,
together with the facts, that corresponding with this line the fascia is devoid
of adipous substance, and the integument thin and delicate, whilst above over
the abdomen, and below over the upper part of the thigh, the meshes of the
fascia are generally loaded with a considerable quantity of adipous tissue,
will account for the permanency and distinctness of the fold of the groin. As
this fold corresponds with Poupart’s ligament, it is taken as a guide to
distinguish between the inguinal and femoral forms of herniae.

The general relations of the superficial fascia are well described by Camper in
the following sentence: “Musculus obliquus igitur externus abdominis, qua parte
carneus est, membrana quadam propria, quali omnes musculi, tegitur, quae sensim
in aponeurosin mutata, ac cum tendineis hujus musculi partibus unita, externe
ac anteriore parte abdomen tegit; finem vero nullibi habere perspicuum est, ad
pubem enim miscet cellulosa membrana, cum ligamento penis in viris ac
clitoridis in feminis, involucrum dat musculo cremasteri, ac aponeuroseos
speciem musculis anterioribus femoris, qua glandulae inguinales, ac cruris vasa
majora obteguntur.” (Icones Herniarum.)

Owing to the varied thickness of the adipous tissue contained in the
superficial fascia at several regions of the same body, and at some
corresponding regions of different individuals, it will be evident that the
depth of the incision required to divide it, so as to expose subjacent
structures, must vary accordingly. Where the superficial fascia, after encasing
the cord, descends into the scrotum, it is also devoid of the fatty tissu.

By the removal of the superficial fascia and glands we expose the aponeurosis
of the external oblique muscle, A a, Pl. 28, (constituting the third
layer of the groin,) and also the fascia of the thigh, H L. These strong
fibrous structures will be observed to hold still in situ the other
parts, and to be the chief agents in determining the normal form of this
region.

The inguino-femoral region, as being the seat of hernial protrusions, may in
this stage of the dissection be conveniently described as a space formed of two
triangles—the one inguinal, the other femoral, placed base to base. The
inguinal triangle may be drawn between the points, B C D, Pl. 28, while the
femoral triangle may be marked by the points, C D N. The conjoined bases of
these triangles correspond to Poupart’s ligament along the line, C D. The
inguinal varieties of herniae occur immediately above the line, C D, while the
femoral varieties of herniae take place below this line. The herniae of the
inguinal triangle are, therefore, distinguishable from those of the femoral
triangle by a reference to the line, C D, or Poupart’s ligament.

The aponeurosis of the external oblique muscle occupies the whole of that space
which I have marked as the inguinal triangle, B C D, Pl. 28. The fleshy fibres
of the muscle, A, after forming the lateral wall of the abdomen, descend to the
level of C, the iliac spinous process, and here give off the inguinal part of
their broad tendon, a. The fibres of this part of the tendon descend
obliquely downwards and forwards to become inserted at the median line of the
abdomen into the linea alba, B D, as also into the symphysis and crista of the
os pubis. The lower band of the fibres of this tendinous sheath—viz., that
which is stretched between C, the iliac spine, and D, the crista pubis, is
named Poupart’s ligament; and this is strongly connected with H, the iliac
portion of the fascia lata of the thigh.

Poupart’s ligament is not stretched tensely in a right line, like the string of
a bow, between the points, C and D. With regard to these points it is lax, and
curves down towards the thigh like the arc of a circle. The degree of tension
which it manifests when the thigh is in the extended position is chiefly owing
to its connexion with the fascia lata. If in this position of the limb we sever
the connexion between the ligament and fascia, the former becomes relaxed in
the same degree as it does when we flex the thigh upon the abdomen. The utmost
degree of relaxation which can be given to Poupart’s ligament is effected by
flexing the thigh towards the abdomen, at the same time that we support the
body forwards. This fact has its practical application in connexion with the
reduction of herniae.

Immediately above the middle of Poupart’s ligament, at the point E, Pl. 28, we
observe the commencement of a separation taking place among the fibres of the
aponeurosis. These divide into two bands, which, gradually widening from each
other as they proceed inwards, become inserted, the upper one into the
symphysis pubis, the lower into the spine and pectineal ridge of this bone. The
lower band identifies itself with Poupart’s ligament. The interval which is
thus formed by the separation of these fibres assumes the appearance of an
acute triangle, the apex of which is at E, and the base at D. But the outer end
of this interval is rounded off by certain fibres which cross those of the
bands at varying angles. At this place, the aponeurosis, thus constituted of
fibres disposed crossways, is elongated into a canal, forming an envelope for
the cord, K. This elongation is named the “external spermatic fascia,” and is
continued over the cord as far as the testicle. In the female, a similar canal
encloses the round ligament of the uterus. From the above-mentioned facts, it
will appear that the so-called “external abdominal ring” does not exist as an
aperture with defined margins formed in the tendon of the external oblique
muscle. It is only when we divide the spermatic fascia upon the cord at K, that
we form the external ring, and then it must be regarded as an artificial
opening, as at D, Pl. 29.

The part of the groin where the spermatic fascia is first derived from the
aponeurosis, so as to envelope the cord, varies in several individuals; and
thereupon depends, in great measure, the strength or weakness of the groin. In
some cases, the cord becomes pendulous as far outwards as the point E, Pl. 28,
which corresponds to the internal ring, thereby offering a direct passage for
the hernial protrusion. In other instances, the two bands of the aponeurosis,
known as the “pillars of the ring,” together with the transverse fibres, or
“intercolumnar fascia,” firmly embrace and support the cord as far inwards as
the point K, and by the oblique direction thus given to the cord in traversing
the inguinal parietes, these parts are fortified against the occurrence of
hernia. In Pl. 28, the cord, K, will be observed to drop over the lower band of
fibres, (“external pillar of the ring,”) and to have D, the crista pubis, on
its inner side. In Pl. 29, the upper band of fibres (“internal pillar of the
ring”) may be seen proceeding to its insertion into the symphysis pubis. When a
hernial tumour protrudes at the situation K, it is invested, in the same manner
as the cord, by the spermatic fascia, and holds in respect to the fibrous bands
or pillars the same relations also as this part.

After removing the tendon of the external oblique muscle, A a, Pl. 28,
together with its spermatic elongation, E, we expose the internal oblique, F E,
Pl. 29, and the cremaster, constituting the fourth inguinal
layer. The fleshy part of this muscle, F E, occupies a much greater extent
of the inguinal region than does that of the external oblique. Whilst the
fleshy fibres of the latter terminate on a level with C, the iliac spine, those
of the internal oblique are continued down as far as the external abdominal
ring, E D h, and even protrude through this place in the form of a
cremaster. The muscular fibres of the internal oblique terminate internally at
the linea semilunaris, g; while Poupart’s ligament, the spinous process
and crest of the ilium, give origin to them externally. At the linea
semilunaris, the tendon of the internal oblique is described as dividing into
two layers, which passing, one before and the other behind the rectus
abdominis, thus enclose this muscle in a sheath, after which they are inserted
into the linea alba, G. The direction of the fibres of the inguinal portion of
the muscle, F E, is obliquely downwards and forwards, and here they are firmly
overlaid by the aponeurosis of the external oblique.

The cremaster muscle manifests itself as being a part of the internal oblique,
viewing this in its totality. Cloquet (Recherches anatomiques sur les Hernies
de l’Abdomen) first demonstrated the correctness of this idea.

The oblique and serial arrangement of the muscular fibres of the internal
oblique, F, Pl. 29, is seen to be continued upon the spermatic cord by the
fibres of the cremaster, E e. These fibres, like those of the lower border of
the internal oblique, arise from the middle of Poupart’s ligament, and after
descending over the cord as far as the testicle in the form of a series of
inverted loops, e, again ascend to join the tendon of the internal
oblique, by which they become inserted into the crest and pectineal ridge of
the os pubis. The peculiar looping arrangement exhibited by the cremasteric
fibres indicates the fact that the testicle, during its descent from the loins
to the scrotum, carried with it a muscular covering, at the expense of the
internal oblique muscle. The cremaster, therefore, is to be interpreted as a
production of the internal oblique, just as the spermatic fascia is an
elongation of the external oblique. The hernia, which follows the course of the
spermatic vessels, must therefore necessarily become invested by cremasteric
fibres.

The fascia lata, H, Pl. 28, being strongly connected and continuous with
Poupart’s ligament along its inferior border, the boundary line, which
Poupart’s ligament is described as drawing between the abdomen and thigh, must
be considered as merely an artificial one.

In the upper region of the thigh the fascia lata is divided into two
parts—viz., H, the iliac part, and L, the pubic. The iliac part, H, which is
external, and occupying a higher plane than the pubic part, is attached to
Poupart’s ligament along its whole extent, from C to D, Pl. 28; that is, from
the anterior iliac spinous process to the crista pubis. From this latter point
over the upper and inner part of the thigh, the iliac division of the fascia
appears to terminate in an edge of crescentic shape, h; but this
appearance is only given to it by our separating the superficial fascia with
which it is, in the natural state of the parts, blended. The pubic part of the
fascia, L, Pl. 28, which is much thinner than the iliac part, covers the
pectineus muscle, and is attached to the crest and pectineal ridge of the os
pubis, occupying a plane, therefore, below the iliac part, and in this way
passes outwards beneath the sheath of the femoral vessels, K I, Pl. 29. These
two divisions of the fascia lata, although separated above, are united and
continuous on the same plane below. An interval is thus formed between them for
the space of about two inches below the inner third of Poupart’s ligament; and
this interval is known as the “saphenous opening,” L h, Pl. 28. Through
this opening, the saphena vein, O, Pl. 29, enters the femoral vein, I.

From the foregoing remarks it will appear that no such aperture as that which
is named “saphenous,” and described as being shaped in the manner of L
h, Pl. 28, with its “upper and lower cornua,” and its “falciform
process,” or edge, h, exists naturally. Nor need we be surprised,
therefore, that so accurate an observer as Soemmering (de Corporis Humani
Fabrica) appears to have taken no notice of it.

Whilst the pubic part of the fascia lata passes beneath the sheath of the
femoral vessels, K I, Pl. 29, the iliac part, H h, blends by its
falciform margin with the superficial fascia, and also with N n, the
sheath of the femoral vessels. The so-called saphenous opening, therefore, is
naturally masked by the superficial fascia; and this membrane being here
perforated for the passage of the saphena vein, and its tributary branches, as
also the efferent vessels of the lymphatic glands, is termed “cribriform.”

The femoral vessels, K I, contained in their proper sheath, lie immediately
beneath the iliac part of the fascia lata, in that angle which is expressed by
Poupart’s ligament, along the line C D above; by the sartorius muscle in the
line C M externally; and by a line drawn from D to N, corresponding to the
pectineus muscle internally. The femoral vein, I, lies close to the outer
margin of the saphenous opening. The artery, K, lies close to the outer side of
the vein; and external to the artery is seen, L, the anterior crural nerve,
sending off its superficial and deep branches.

When a femoral hernia protrudes at the saphenous space L h, Pl. 28, the
dense falciform process, h, embraces its outer side, while the pubic
portion of the fascia, L, lies beneath it. The cord, K, is placed on the inner
side of the hernia; the cribriform fascia covers it; and the upper end of the
saphena vein, M, passes beneath its lower border. The upper cornu, h,
Pl. 29, of the falciform process would seem, by its situation, to be one of the
parts which constrict a crural hernia. An inguinal hernia, which descends the
cord, K, Pl. 28, provided it passes no further than the point indicated at K,
and a crural hernia turning upwards from the saphenous interval over the cord
at K, are very likely to present some difficulty in distinctive diagnosis.

DESCRIPTION OF THE FIGURES OF PLATES 28 & 29.

PLATE 28.

A. The fleshy part of the external oblique muscle; a, its tendon
icovering the rectus muscle.

B. The umbilicus.

C. The anterior superior spinous process of the ilium.

D. The spinous process of the os pubis.

E. The point where in this instance the fibres of the aponeurotic tendon iof
the external oblique muscle begin to separate and form the pillars iof the
external ring.

F G. See Plate 29.

H. The fascia lata—its iliac portion. The letter indicates the isituation of
the common femoral artery; h, the falciform edge of the isaphenous
opening.

I. The sartorius muscle covered by a process of the fascia lata.

K. The spermatic fascia derived from the external oblique tendon.

L. The pubic part of the fascia lata forming the inner and posterior iboundary
of the saphenous opening.

M. The saphenous vein.

N. A tributary vein coming from the fore part of the thigh.

Plate 28

PLATE 29.

A. The muscular part of the external oblique; a, its tendon.

B. The umbilicus.

C. The anterior superior iliac spine.

D. The spine of the os pubis.

E. The cremasteric fibres, within the external ring, surrounding the icord;
e, the cremasteric fibres looping over the cord outside the ring.

F. The muscular part of the internal oblique giving off, E, the icremaster; its
tendon sheathing the rectus muscle.

G. The linea alba; f, g, the linea semilunaris.

H. The iliac part of the fascia lata; h, the upper cornu of its
ifalciform process.

I. The femoral vein.

K. The femoral artery.

L. The anterior crural nerve.

M. The sartorius muscle.

N. The sheath of the femoral vessels; n, its upper part.

O. The saphena vein.

P. The pubic part of the fascia lata.

Plate 29

COMMENTARY ON PLATES 30 & 31.

THE SURGICAL DISSECTION OF THE FIFTH, SIXTH, SEVENTH, AND EIGHTH LAYERS OF THE
INGUINAL REGION, AND THEIR CONNEXION WITH THOSE OF THE THIGH.

When we remove the internal oblique and cremaster muscles, we expose the
transverse muscle, which may be regarded as the fifth inguinal layer, F,
Pl. 30. This muscle is similar in shape and dimensions to the internal oblique.
The connexions of both are also similar, inasmuch as they arise from the inner
edge of the crista ilii, and from the outer half of, V, Poupart’s ligament. The
fleshy fibres of these two muscles vary but little in direction, and terminate
at the same place—viz., the linea semilunaris, which marks the outer border of
the rectus muscle. But whilst the fleshy parts of these three abdominal
muscles, D E F, form successive strata in the groin, their aponeurotic tendons
present the following peculiarities of arrangement in respect to the rectus
muscle. The tendon of the external oblique, d, passes altogether in
front of the rectus; that of the internal oblique is split opposite the linea
semilunaris into two layers, which enclose the rectus between them as they pass
to be inserted into the linea alba. But midway between the navel and pubes, at
the point marked G, both layers of the tendon are found to pass in front of the
rectus. The tendon of the transverse muscle passes behind the rectus; but
opposite the point G, it joins both layers of the internal oblique tendon, and
with this passes in front of the rectus. The fibrous structure thus constituted
by the union of the tendons of the internal oblique and transverse muscles,
e f, is named the “conjoined tendon.”

The conjoined tendon, f, Plates 30 and 31, appears as a continuation of
the linea semilunaris, for this latter is in itself a result of the union of
the tendons of the abdominal muscles at the external border of the rectus. As
the conjoined tendon curves so far outwards to its insertion into the pectineal
ridge of the pubic bone, as to occupy a situation immediately behind the
external ring, it thereby fortifies this part against the occurrence of a
direct protrusion of the bowel. But the breadth, as well as the density, of
this tendon varies in several individuals, and these will accordingly be more
or less liable to the occurrence of hernia.

The arched inferior border of the transverse muscle, F, Plate 30, expresses by
its abrupt termination that some part is wanting to it; and this appearance,
together with the fact that the fibres of this part of the muscle blend with
those of the internal oblique and cremaster, and cannot be separated except by
severing the connexion, at once suggests the idea that the cremaster is a
derivation from both these muscles.

Assuming this to be the case, therefore, it follows that when the dissector
removes the cremaster from the space L h, he himself causes this vacancy
in the muscular parietes of the groin to occur, and at the same time gives
unnatural definition to the lower border of the transverse and oblique muscles.
In a dissection so conducted, the cord is made to assume the variable positions
which anatomists report it to have in respect to the neighbouring muscles. But
when we view nature as she is, and not as fashioned by the scalpel, we never
fail to find an easy explanation of her form.

In the foetus, prior to the descent of the testicle, the cremaster muscle does
not exist. (Cloquet, op cit.) From this we infer, that those parts of the
muscles, E F, Plate 30, which at a subsequent period are converted into a
cremaster, entirely occupy the space L h. In the adult body, where one
of the testicles has been arrested in the inguinal canal, the muscles, E F, do
not present a defined arched margin, above the vacant space L h, but are
continued (as in the foetus) as low down as the external abdominal ring. In the
adult, where the testicle has descended to the scrotum, the cremaster exists,
and is serially continuous with the muscles, E F, covering the space L
h; the meaning of which is, that the cremasteric parts of the muscles, E
F, cover this space. The name cremaster therefore must not cancel the fact that
the fibres so named are parts of the muscles, E F. Again, in the female devoid
of a cremaster, the muscles, E F, present of their full quantities, having
sustained no diminution of their bulk by the formation of a cremaster. But when
an external inguinal hernia occurs in the female body, the bowel during its
descent carries before it a cremasteric covering at the expense of the muscles
E F, just in the same way as the testicle does in the foetus. (Cloquet.)

From the above-mentioned facts, viewed comparatively, it seems that the
following inferences may be legitimately drawn:—1st, that the space L h
does not naturally exist devoid of a muscular covering; for, in fact, the
cremaster overlies this situation; 2nd, that the name cremaster is one given to
the lower fibres of the internal oblique and transverse muscles which cover
this space; and 3rd, that to separate the cremasteric elongation of these
muscles, and then describe them as presenting a defined arched margin, an inch
or two above Poupart’s ligament, is an act as arbitrary on the part of the
dissector as if he were to subdivide these muscles still more, and, while
regarding the subdivisions as different structures, to give them names of
different signification. When once we consent to regard the cremaster as
constituted of the fibres originally proper to the muscles, E F, we then are
led to the discovery of the true relations of the cord in respect to these
muscles.

On removing the transverse muscle, we expose the inguinal part of the
transversalis fascia—the sixth inguinal layer, L h, Plate 30—K
k, Plate 31. This fascia or membrane affords a general lining to the
abdominal walls, in some parts of which it presents of a denser and stronger
texture than in others. It is stretched over the abdomen between the muscles
and the peritonaeum. The fascia iliaca, the fascia pelvica, and the fascia
transversalis, are only regional divisions of the one general membrane. On
viewing this fascia in its totality, I find it to exhibit many features in
common with those other fibrous structures which envelope serous cavities. The
transversalis fascia supports externally the peritonaeum, in the same way as
the dura mater supports the arachnoid membrane, or as the pleural fascia
supports the serous pleura. While the serous membranes form completely shut
sacs, the fibrous membranes which lie external to those sacs are pierced by the
vessels which course between them and the serous membranes, and afford sheaths
or envelopes for these vessels in their passage from the interior to the
external parts. The sheath, H h, Plates 30 and 31, which surrounds the
spermatic vessels, and the sheath, R, Plate 31, which envelopes the crural
vessels, are elongations of the fascia transversalis.

In the groin, the transversalis fascia, K k, Plate 31, presents, in
general, so dense a texture as to offer considerable resistance to visceral
pressure. Here it is stretched between the transverse muscle, F, Plate 31, and
the peritonaeum, I. It adheres to the external surface of the peritonaeum, and
to the internal surface of the transverse muscle, by means of an intervening
cellular tissue. It is connected below to Poupart’s ligament, along the line of
which it joins the fascia iliaca. It lines the lower posterior aspect of the
rectus muscle, where this is devoid of its sheath; and it is incorporated with
f, the conjoined tendon, thereby fencing the external abdominal ring.
Immediately above the middle of Poupart’s ligament, this membrane, at the point
marked h, Plate 30, is pouched into a canal-shaped elongation, which
invests the spermatic vessels as far as the testicle in the scrotum; and to
this elongation is given the names “fascia spermatica interna” (Cooper),
“fascia infundibuliform” (Cloquet). The same part, when it encloses an external
oblique hernia, is named “fascia propria.” The neck or inlet of this
funnel-shaped canal is oval, and named the “internal abdominal ring.” As this
ring looks towards the interior of the abdomen, and forms the entrance of the
funnel-shaped canal, it cannot of course be seen from before until we slit open
this canal. Compare the parts marked H h in Plates 30 and 31.

The inguinal and iliac portions of the fascia transversalis join along the line
of Poupart’s ligament, A C. The iliac vessels, in their passage to the thigh,
encounter the fascia at the middle third of the crural arch formed by the
ligament, and take an investment (the sheath, R) from the fascia. The fore part
of this sheath is mentioned as formed by the fascia transversalis—the back part
by the fascia iliaca; but these distinctions are merely nominal, and it is
therefore unnecessary to dwell upon them. The sheath of the femoral vessels is
also funnel-shaped, and surrounds them on all sides. Its broad entrance lies
beneath the middle of Poupart’s ligament. Several septa are met with in its
interior. These serve to separate the femoral vessels from each other. The
femoral vein, O, Plate 30, is separated from the falciform margin, S s,
of the saphenous opening by one of these septa. Between this septum and the
falx an interval occurs, and through it the crural hernia usually descends.
These parts will be more particularly noticed when considering the anatomy of
crural hernia.

Beneath the fascia transversalis is found the subserous cellular membrane,
which serves as a connecting medium between the fascia and the peritonaeum.
This cellular membrane may be considered as the seventh inguinal layer.
It is described by Scarpa (sull’ Ernie) as forming an investment for the
spermatic vessels inside the sheath, where it is copious, especially in old
inguinal hernia. It is also sometimes mixed with fatty tissue. In it is found
embedded the infantile cord—the remains of the upper part of the peritoneal
tunica vaginalis—a structure which will be considered in connexion with
congenital herniae.

By removing the subserous cellular tissue, we lay bare the peritonaeum, which
forms the eighth layer of the inguinal region. Upon it the epigastric
and spermatic vessels are seen to rest. These vessels course between the fascia
transversalis and the peritonaeum. The internal ring which is formed in the
fascia, K h, may be now seen to be closed by the peritonaeum, I. The
inguinal canal, therefore, does not, in the normal state of these parts,
communicate with the general serous cavity; and here it must be evident that
before the bowel, which is situated immediately behind the peritonaeum, I, can
be received into the canal, H h, it must either rupture that membrane,
or elongate it in the form of a sac.

The exact position which the epigastric, L, Plate 31, and spermatic vessels, M,
bear in respect to the internal ring, is a point of chief importance in the
surgical anatomy of the groin; for the various forms of herniae which protrude
through this part have an intimate relation to these vessels. The epigastric
artery, in general, arises from the external iliac, close above the middle of
Poupart’s ligament, and ascends the inguinal wall in an oblique course towards
the navel. It applies itself to the inner border of the internal ring, and here
it is crossed on its outer side by the spermatic vessels, as these are about to
enter the inguinal canal.

The inguinal canal is the natural channel through which the spermatic vessels
traverse the groin on their way to the testicle in the scrotum. In the remarks
which have been already made respecting the several layers of structures found
in the groin, I endeavoured to realize the idea of an inguinal canal as
consisting of elongations of these layers invaginated the one within the other,
the outermost layer being the integument of the groin elongated into the
scrotal skin, whilst the innermost layer consisted of the transversalis fascia
elongated into the fascia spermatica interna, or sheath. The peritonaeum, which
forms the eighth layer of the groin, was seen to be drawn across the internal
ring of this canal above in such a way as to close it completely, whilst all
the other layers, seven in number, were described as being continued over the
spermatic vessels in the form of funnel-shaped investments, as far down as the
testicle.

With the ideas of an inguinal canal thus naturally constituted, I need not
hesitate to assert that the form, the extent, and the boundaries of the
inguinal canal, as given by the descriptive anatomist, are purely conventional,
and do not exist until after dissection; for which reason, and also because the
form and condition of these parts so described and dissected do not appear
absolutely to correspond in any two individuals, I omit to mention the scale of
measurements drawn up by some eminent surgeons, with the object of determining
the precise relative position of the several parts of the inguinal region.

The existence of an inguinal canal consisting, as I have described it, of
funnel-shaped elongations from the several inguinal layers continued over the
cord as far as the testicle, renders the adult male especially liable to
hernial protrusions at this part. The oblique direction of the canal is, in
some measure, a safeguard against these accidents; but this obliquity is not of
the same degree in all bodies, and hence some are naturally more prone to
herniae than others.

DESCRIPTION OF THE FIGURES OF PLATES 30 & 31.

PLATE 30.

A. The anterior superior iliac spine.

B. The umbilicus.

C. The spine of the pubis.

D. The external oblique muscle; d, its tendon. .

E. The internal oblique muscle; e, its tendon.

F. The transverse muscle; f, its tendon, forming, with e, the
conjoined tendon.

G. The rectus muscle enclosed in its sheath.

H. The fascia spermatica interna covering the cord; h, its funnel-shaped
extremity.

I, K, L, M. See Plate 31.

N. The femoral artery; n, its profunda branch.

O. The femoral vein.

P. The saphena vein.

Q. The sartorius muscle.

R. The sheath of the femoral vessels.

S. The falciform margin of the saphenous opening.

T. The anterior crural nerve.

U. The pubic portion of the fascia lata.

V. The iliac portion attached to Poupart’s ligament.

W. The lower part of the iliacus muscle.

Plate 30

PLATE 31.

A. The anterior superior iliac spine.

B. The umbilicus.

C. The spine of the pubis.

D. The external oblique muscle; d, its tendon; d*, the external
ring.

E. The internal oblique muscle.

F. The transverse muscle; f, its tendon; forming, with e, the
conjoined tendon.

G. The rectus muscle laid bare.

H h. The fascia spermatica interna laid open above and below d*,
the external ring.

I. The peritonaeum closing the internal ring.

K. The fascia transversalis; k, its pubic part.

L. The epigastric artery and veins.

M. The spermatic artery, veins, and vas deferens bending round the epigastric
artery at the internal ring; m, the same vessels below the external
ring.

N. The femoral artery; n, its profunda branch.

O. The femoral vein, joined by—

P. The saphena vein.

Q. The sartorius muscle.

R. The sheath of the femoral vessels.

S S. The falciform margin of the saphenous opening,

T. The anterior crural nerve.

U. The pubic part of the fascia lata.

V. The iliac part of the fascia lata.

W. The lower part of the iliacus muscle.

Plate 31

COMMENTARY ON PLATES 32, 33, & 34.

THE DISSECTION OF THE OBLIQUE OR EXTERNAL AND THE DIRECT OR INTERNAL INGUINAL
HERNIAE.

The order in which the herniary bowel takes its investments from the eight
layers of the inguinal region, is precisely the reverse of that order in which
these layers present in the dissection from before backwards. The innermost
layer of the inguinal region is the peritonaeum, and from this membrane the
intestine, when about to protrude, derives its first covering. This covering
constitutes the hernial sac. Almost all varieties of inguinal herniae are said
to be enveloped in a sac, or elongation of the peritonaeum. This is accounted
as the general rule. The exceptions to the rule are mentioned as occurring in
the following modes: 1st, the caecum and sigmoid flexure of the colon, which
are devoid of mesenteries, and only partially covered by the peritonaeum, may
slip down behind this membrane, and become hernial; 2nd, the inguinal part of
the peritonaeum may suffer rupture, and allow the intestine to protrude through
the opening. When a hernia occurs under either of these circumstances, it will
be found deprived of a sac.

All the blood vessels and nerves of the abdomen lie external to the
peritonaeum. Those vessels which traverse the abdomen on their way to the
external organs course outside the peritonaeum; and at the places where they
enter the abdominal parietes, the membrane is reflected from them. This
disposition of the peritonaeum in respect to the spermatic and iliac vessels is
exhibited in Plate 32.

The part of the peritonaeum which lines the inguinal parietes does not (in the
normal state of the adult body) exhibit any aperture corresponding to that
named the internal ring. The membrane is in this place, as elsewhere,
continuous throughout, being extended over the ring, as also over other
localities, where subjacent structures may be in part wanting. It is in these
places, where the membrane happens to be unsupported, that herniae are most
liable to occur. And it must be added, that the natural form of the internal
surface of the groin is such as to guide the viscera under pressure directly
against those parts which are the weakest.

The inner surface of the groin is divided into two pouches or fossae, by an
intervening crescentic fold of the peritonaeum, which corresponds with the
situation of the epigastric vessels. This fold is formed by the epigastric
vessels and the umbilical ligament, which, being tenser and shorter than the
peritonaeum, thereby cause this membrane to project. The outer fossa represents
a triangular space, the apex of which is below, at P; the base being formed by
the fibres of the transverse muscle above; the inner side by the epigastric
artery; and the outer side by Poupart’s ligament. The apex of this inverted
triangle is opposite the internal ring. The inner fossa is bounded by the
epigastric artery externally; by the margin of the rectus muscle internally;
and by the os pubis and inner end of Poupart’s ligament inferiorly. The inner
fossa is opposite the external abdominal ring, and is known as the triangle of
Hesselbach.

The two peritonaeal fossae being named external and internal, in reference to
the situation of the epigastric vessels, we find that the two varieties of
inguinal herniae which occur in these fossae are named external and internal
also, in reference to the same part.

The external inguinal hernia, so called from its commencing in the outer
peritonaeal fossa, on the outer side of the epigastric artery, takes a covering
from the peritonaeum of this place, and pushes forward into the internal
abdominal ring at the point marked P, Plate 32. In this place, the incipient
hernia or bubonocele, covered by its sac, lies on the forepart of the spermatic
vessels, and becomes invested by those same coverings which constitute the
inguinal canal, through which these vessels pass. In this stage of the hernia,
its situation in respect to the epigastric artery is truly external, and in
respect to the spermatic vessels, anterior, while the protruded intestine
itself is separated from actual contact with either of these vessels by its
proper sac. The bubonocele, projecting through the internal ring at the
situation marked F, (Plate 33,) midway between A, the anterior iliac spine, and
I, the pubic spine, continues to increase in size; but as its further progress
from behind directly forwards becomes arrested by the tense resisting
aponeurosis of the external oblique muscle, h, it changes its course
obliquely inwards along the canal, traversing this canal with the spermatic
vessels, which still lie behind it, and, lastly, makes its exit at the external
ring, H. The obliquity of this course, pursued by the hernia, from the internal
to the external ring, has gained for it the name of oblique hernia. In
this stage of the hernial protrusion, the only part of it which may be truly
named external is the neck of its sac, F, for the elongated body, G, of the
hernia lies now actually in front of the epigastric artery, P, and this vessel
is separated from the anterior wall of the canal, H h, by an interval
equal to the bulk of the hernia. While the hernia occupies the canal, F H,
without projecting through the external ring, H, it is named “incomplete.” When
it has passed the external ring, H, so as to form a tumour of the size and in
the situation of f g, it is named “complete.” When, lastly, the hernia
has extended itself so far as to occupy the whole length of the cord, and reach
the scrotum, it is termed “scrotal hernia.” These names, it will be seen, are
given only to characterise the several stages of the one kind of hernia—viz.,
that which commences to form at a situation external to the epigastric artery,
and, after following the course of the spermatic vessels through the inguinal
canal, at length terminates in the scrotum.

The external inguinal hernia having entered the canal, P, (Plate 32,) at a
situation immediately in front of the spermatic vessels, continues, in the
several stages of its descent, to hold the same relation to these vessels
through the whole length of the canal, even as far as the testicle in the
scrotum. This hernia, however, when of long standing and large size, is known
to separate the spermatic vessels from each other in such a way, that some are
found to lie on its fore part—others to its outer side. However great may be
the size of this hernia, even when it becomes scrotal, still the testicle is
invariably found below it. This fact is accounted for by the circumstance, that
the lower end of the spermatic envelopes is attached so firmly to the coats of
the testicle as to prevent the hernia from either distending and elongating
them to a level below this organ, or from entering the cavity of the tunica
vaginalis.

The external form of inguinal hernia is, comparatively speaking, but rarely
seen in the female. When it does occur in this sex, its position, investments,
and course through the inguinal canal, where it accompanies the round ligament
of the uterus, are the same as in the male. When the hernia escapes through the
external abdominal ring of the female groin, it is found to lodge in the labium
pudendi. In the male body, the testicle and spermatic cord, which have carried
before them investments derived from all the layers of the inguinal region,
have, as it were, already marked out the track to be followed by the hernia,
and prepared for it its several coverings. The muscular parietes of the male
inguinal region, from which the loose cremaster muscle has been derived, have
by this circumstance become weakened, and hence the more frequent occurrence of
external inguinal hernia in the male. But in the female, where no such process
has taken place, and where a cremaster does not exist at the expense of the
internal oblique and transverse muscles, the inguinal parietes remain more
compact, and are less liable to suffer distention in the course of the uterine
ligament.

The internal inguinal hernia takes its peritonaeal covering (the sac)
from the inner fossa, Q R, Plate 32, internal to the epigastric artery, and
forces directly forwards through the external abdominal ring, carrying
investments from each of such structures as it meets with in this locality of
the groin. As the external ring, H, Plate 34, is opposite the inner peritonaeal
fossa, Q R, Plate 32, this hernia, which protrudes thus immediately from behind
forwards, is also named direct. In this way these two varieties of
hernia, (the external, Plate 33, and the internal, Plate 34,) though commencing
in different situations, P and R, Plate 32, within the abdomen, arrive at the
same place—viz., the external ring, H, Plates 33 and 34. The coverings of the
internal hernia, Plate 34, though not derived exactly from the same locality as
those which invest the cord and the external variety, are, nevertheless, but
different parts of the same structures; these are, 1st, the peritonaeum, G,
which forms its sac; 2nd, the pubic part of the fascia transversalis; 3rd, the
conjoined tendon itself, or (according as the hernia may occur further from the
mesial line) the cremaster, which, in common with the internal oblique and
transverse muscles, terminates in this tendon; 4th, the external spermatic
fascia, derived from the margins of the external ring; 5th, the superficial
fascia and integuments.

The coverings of the internal inguinal hernia are (as to number) variously
described by authors. Thus with respect to the conjoined tendon, the hernia is
said, in some instances, to take an investment of this structure; in others, to
pass through a cleft in its fibres; in others, to escape by its outer margin.
Again, the cremaster muscle is stated by some to cover this hernia; by others,
to be rarely met with, as forming one of its coverings; and by others, never.
Lastly, it is doubted by some whether this hernia is even covered by a
protrusion of the fascia transversalis in all instances. [Footnote]

[Footnote: Mr. Lawrence (Treatise on Ruptures) remarks, “How often it may be
invested by a protrusion of the fascia transversalis, I cannot hitherto
determine.” Mr. Stanley has presented to St. Bartholomew’s Hospital several
specimens of this hernia invested by the fascia. Hesselbach speaks of the
fascia as being always present. Cloquet mentions it as being present always,
except in such cases as where, by being ruptured, the sac protrudes through it.
Langenbeck states that the fascia is constantly protruded as a covering to this
hernia: “Quia hernia inguinalis interna non in canalis abdominalis aperturam
internam transit, tunicam vaginalem communem intrare nequit; parietem autem
canalis abdominalis internum aponeuroticum, in quo fovea inguinalis interna, et
qui ex adverso annulo abdominali est, ante se per annulum trudit.” (Comment, ad
illust. Herniarum, &c.) Perhaps the readiest and surest explanation which
can be given to these differences of opinion may be had from the following
remark:—“Culter enim semper has partes extricat, quae involucro adeo inhaerent,
ut pro lubitu musculum (membranam) efformare queas unde magnam illam inter
anatomicos discrepantiam ortam conjicio.” (Camper. Icones Herniarum.)]

The variety in the number of investments of the internal inguinal hernia
(especially as regards the presence or absence of the conjoined tendon and
cremaster) appears to me to be dependent, 1st, upon the position whereat this
hernia occurs; 2nd, upon the state of the parts through which it passes; and
3rd, upon the manner in which the dissection happens to be conducted.

The precise relations which the internal hernia holds in respect to the
epigastric and spermatic vessels are also mainly dependent (as in the external
variety) upon the situation where it traverses the groin. The epigastric artery
courses outside the neck of its sac, sometimes in close connexion with this
part—at other times, at some distance from it, according as the neck may happen
to be wide and near the vessel, or narrow, and removed from it nearer to the
median line. At the external ring, H, (Plate 34,) the sac of this hernia,
g, protrudes on the inner side of the spermatic vessels, f; and
the size of the hernia distending the ring, removes these vessels at a
considerable interval from, I, the crista pubis. At the ring, H, (Plate 34,)
the investments, g f, of the direct hernia are not always
distinct from those of the oblique hernia, g f, (Plate 33); for whilst
in both varieties the intestine and the spermatic vessels are separated from
actual contact by the sac, yet it is true that the direct hernia, as well as
the oblique, may occupy the inguinal canal. It is in relation to the epigastric
artery alone that the direct hernia differs essentially from the oblique
variety; for I find that both may be enclosed in the same structures as invest
the spermatic vessels.

The external ring of the male groin is larger than that of the female; and this
circumstance, with others of a like nature, may account for the fact, that the
female is very rarely the subject of the direct hernia. In the male, the direct
hernia is found to occur much less frequently than the oblique, and this we
might, a priori, expect, from the anatomical disposition of the parts.
But it is true, nevertheless, that the part where the direct hernia occurs is
not defended so completely in some male bodies as it is in others. The
conjoined tendon, which is described as shielding the external ring, is in some
cases very weak, and in others so narrow, as to offer but little support to
this part of the groin.

DESCRIPTION OF THE FIGURES OF PLATES 32, 33, & 34.

PLATE 32.

A. That part of the ilium which abuts against the sacrum.

B. The spine of the ischium.

C. The tuberosity of the ischium.

D. The symphysis pubis.

E. Situation of the anterior superior iliac spine.

F. Crest of the ilium.

G. Iliacus muscle.

H. Psoas magnus muscle supporting the spermatic vessels.

I. Transversalis muscle.

K. Termination of the sheath of the rectus muscle.

L1 L2 L3. The iliac, transverse and pelvic portions of the transversalis
fascia.

M M. The peritonaeum lining the groin.

N. The epigastric vessels lying between the peritonaeum, M, and the
transversalis fascia, L2. O. The umbilical ligament.

P. The neck of the sac of an external inguinal hernia formed before the
spermatic vessels.

Q. An interval which occasionally occurs between the umbilical ligament and the
epigastric artery.

R and Q. Situations where the direct inguinal hernia occurs when, as in this
case, the umbilical ligament crosses the space named the internal fossa—the
triangle of Hesselbach.

S. Lower part of the right spermatic cord.

T. The bulb of the urethra.

U. External iliac vein covered by the peritonaeum.

V. External iliac artery covered by the peritonaeum.

W. Internal iliac artery.

X. Common iliac artery.

Plate 32

PLATE 33.—The External Inguinal Hernia.

A. Anterior iliac spinous process.

B. The umbilicus.

C. Fleshy part of the external oblique muscle; c, its tendon.

D. Fleshy part of the internal oblique muscle; d, its tendon.

E. Transversalis muscle; e, the conjoined tendon.

F f. The funnel-shaped sheath of the spermatic vessels covering the
external hernia; upon it are seen the cremasteric fibres.

G g. The peritonaeal covering or sac of the external hernia within the
sheath.

H. The external abdominal ring.

I. The crista pubis.

K k. The saphenous opening.

L. The saphena vein.

M. The femoral vein.

N. The femoral artery; n, its profunda branch.

O. The anterior crural nerve.

P. The epigastric vessels overlaid by the neck of the hernia.

Q Q. The sheath of the femoral vessels.

R. The sartorius muscle.

S. The iliacus muscle.

Plate 33

PLATE 34.—The Internal Inguinal Hernia.

The letters indicate the same parts as in Plate 33

Plate 34

COMMENTARY ON PLATES 35, 36, 37, & 38.

THE DISTINCTIVE DIAGNOSIS BETWEEN EXTERNAL AND INTERNAL INGUINAL HERNIAE, THE
TAXIS, THE SEAT OF STRICTURE, AND THE OPERATION.

A comparison of the relative position of these two varieties of herniae is in
ordinary cases the chief means by which we can determine their distinctive
diagnosis; but oftentimes they are found to exhibit such an interchange of
characters, that the name direct or oblique can no longer serve
to distinguish between them. The nearer the one approaches the usual place of
the other, the more likely are they to be mistaken the one for the other. An
internal hernia may enter the inguinal canal, and become oblique; while an
external hernia, though occupying the canal, may become direct. It is only when
these herniae occur at the situations commonly described, and where they
manifest their broadest contrast, that the following diagnostic signs can be
observed.

The external bubonocele, H, Plate 37, G, Plate 38, when recently formed, may be
detected at a situation midway between the iliac and pubic spinous processes,
where it has entered the internal ring. When the hernia extends itself from
this part, its course will be obliquely inwards, corresponding with the
direction of the inguinal canal. While it still occupies the canal without
passing through the external ring, it is rendered obscure by the restraint of
the external oblique tendon; but yet a degree of fulness may be felt in this
situation. When the hernia has passed the external ring, T, Plate 36, it
dilates considerably, and assumes the form of an oblong swelling, H, Plate 36,
behind which the spermatic vessels are situated. When it has become scrotal,
the cord will be found still on its posterior aspect, while the testicle itself
occupies a situation directly below the swelling.

The internal hernia, H, Plate 38, also traverses the external ring, T, where it
assumes a globular shape, and sometimes projects so far inwards, over the
pubes, C, as to conceal the crista of this bone. As the direction of this
hernia is immediately from behind forwards, the inguinal canal near the
internal ring is found empty, unswollen. The cord, Q, lies external to and
somewhat over the fore part of this hernia; and the testicle does not occupy a
situation exactly beneath the fundus of the sac, (as it does in the external
hernia,) but is found to be placed either at its fore part or its outer side.
This difference as to the relative position of the cord and testicle in both
these forms of herniae, is accounted for under the supposition that whilst the
external variety descends inside the sheaths of the inguinal canal, the
internal variety does not. But this statement cannot apply to all cases of
internal hernia, for this also occasionally enters the canal. Both forms of
inguinal herniae may exist at the same time on the same side: the external, G,
Plate 38, being a bubonocele, still occupying the inguinal canal; while the
internal, H, protrudes through the external ring, T, in the usual way. In this
form of hernia—a compound of the oblique and direct—while the parts remain
still covered by the integuments, it must be difficult to tell its nature, or
to distinguish any mark by which to diagnose the case from one of the external
variety, H, Plate 36, which, on entering the canal at the internal ring,
protrudes at the external ring. In both cases, the swelling produced in the
groin must be exactly of the same size and shape. The epigastric artery in the
case where the two herniae co-exist lies between them, holding in its usual
position with respect to each when occurring separately—that is, on the outer
side of the internal hernia, H, and on the inner side of the external one, G;
and the external hernia, G, not having descended the canal as far as the
external ring, T, allows the internal hernia, H, to assume its usual position
with respect to the cord, Q. [Footnote]

[Footnote: Cases of this double hernia (external and internal) have been met
with by Wilmer, Arnaud, Sandifort, Richter, and others. A plurality of the same
variety of hernia may also occur on the same side. A complete and incomplete
external inguinal hernia existing in the one groin, is recorded by Mr. Aston
Key in his edition of Sir Astley Cooper’s work on Hernia. Sir Astley Cooper
states his having met with three internal inguinal herniae in each inguinal
region. (Ing. et Congenit. Hernire.) ]

Returning, however, to the more frequent conditions of inguinal hernia—viz.,
those in which either the direct or the oblique variety occurs alone—it should
be remembered that a hernia originally oblique, H, Plates 35 and 37, may, when
of long standing, and having attained a large size, destroy, by its
gravitation, the obliquity of the inguinal canal to such a degree as to bring
the internal, H, Plate 35, opposite to the external ring, as at I, and thereby
exhibit all the appearance of a hernia originally direct, I, Plate 37. In such
a case, the epigastric artery, F, which lies on the outer side of the neck of a
truly direct hernia, I, Plate 37, will be found to course on the inner side, G,
of the neck of this false-seeming direct hernia, I, Plate 35.

In the trial made for replacing the protruded bowel by the taxis, two
circumstances should be remembered in order to facilitate this object: 1st, the
abdominal parietes should be relaxed by supporting the trunk forward, and at
the same time flexing the thigh on the trunk; 2nd, as every complete hernial
protrusion becomes distended more or less beyond the seat of stricture—wherever
this may happen to be—its reduction by the taxis should be attempted, with
gradual, gentle, equable pressure, so that the sac may be first emptied of its
fluid. That part of the hernia which protruded last should be replaced first.
The direction in which the hernia protrudes must always determine the direction
in which it is to be reduced. If it be the external or oblique variety, the
viscus is to be pushed upwards, outwards, and backwards; if it be the internal
or direct variety, it is to be reduced by pressure, made upwards and backwards.
Pressure made in this latter direction will serve for the reduction of that
hernia which, from being originally external and oblique, has assumed the usual
position of the internal or direct variety.

The seat of the stricture in an external inguinal hernia is found to be
situated either at the internal ring, corresponding to the neck of the sac, or
at the external ring. Between these two points, which “bound the canal,” and
which are to be regarded merely as passive agents in causing stricture of the
protruding bowel, the lower parts of the transversalis and internal oblique
muscles embrace the herniary sac, and are known at times to be the cause of its
active strangulation or spasm.

The seat of stricture in an internal hernia may be either at the neck of its
sac, I, Plate 37, or at the external ring, T, Plate 38; and according to the
locality where this hernia enters the inguinal wall, the nature of its
stricture will vary. If the hernia pass through a cleft in the conjoined
tendon, f, Plate 38, this structure will constrict its neck all around.
If it pass on the outer margin of this tendon, then the neck of the sac,
bending inwards in order to gain the external ring, will be constricted against
the sharp resisting edge of the tendon. Again, if the hernia enter the inguinal
wall close to the epigastric artery, it will find its way into the inguinal
canal, become invested by the structures forming this part, and here it may
suffer active constriction from the muscular fibres of the transverse and
internal oblique or their cremasteric parts. The external ring may be
considered as always causing some degree of pressure on the hernia which passes
through it.

In both kinds of inguinal herniae, the neck of the sac is described as being
occasionally the seat of stricture, and it certainly is so; but never from a
cause originating in itself per se, or independently of adjacent
structures. The form of the sac of a hernia is influenced by the parts through
which it passes, or which it pushes and elongates before itself. Its neck, H,
Plate 37, is narrow at the internal ring of the fascia transversalis, because
this ring is itself narrowed; it is again narrowed at the external ring, T,
Plate 36, from the same cause. The neck of the sac of a direct hernia, I, Plate
37, being formed in the space of the separated fibres of the conjoined tendon,
or the pubic part of the transversalis fascia, while the sac itself passes
through the resisting tendinous external ring, is equal to the capacities of
these outlets. But if these constricting outlets did not exist, the neck of the
sac would be also wanting. When, however, the neck of the sac has existed in
the embrace of these constricting parts for a considerable period—when it
suffers inflammation and undergoes chronic thickening—then, even though we
liberate the stricture of the internal ring or the external, the neck of the
sac will be found to maintain its narrow diameter, and to have become itself a
real seat of stricture. It is in cases of this latter kind of stricture that
experience has demonstrated the necessity of opening the sac (a proceeding
otherwise not only needless, but objectionable) and dividing its constricted
neck.

The fact that the stricture may be seated in the neck of the sac independent of
the internal ring, and also that the duplicature of the contained bowel may be
adherent to the neck or other part of the interior, or that firm bands of false
membrane may exist so as to constrict the bowel within the sac, are
circumstances which require that this should be opened, and the state of its
contained parts examined, prior to the replacement of the bowel in the abdomen.
If the bowel were adherent to the neck of the sac, we might, when trying to
reduce it by the taxis, produce visceral invagination; or while the stricture
is in the neck of the sac, if we were to return this and its contents en
masse (the “reduction en bloc”) into the abdomen, it is obvious that the
bowel would be still in a state of strangulation, though free of the internal
ring or other opening in the inguinal wall.

The operation for the division of the stricture by the knife is conducted in
the following way: an incision is to be made through the integuments, adipous
membrane, and superficial fascia, of a length and depth sufficient to expose
the tendon of the external oblique muscle for an inch or so above the external
ring; and the hernia for the same extent below the ring. The length of the
incision will require to be varied according to circumstances, but its
direction should be oblique with that of the hernia itself, and also over the
centre of its longitudinal axis, so as to avoid injuring the spermatic vessels.
If the constriction of the hernia be caused by the external ring, a director is
to be inserted beneath this part, and a few of its fibres divided. But when the
stricture is produced by either of the muscles which lie beneath the
aponeurosis of the external oblique, it will be necessary to divide this part
in order to expose and incise them.

When the thickened and indurated neck of the sac is felt to be the cause of the
strangulation, or when the bowel cannot be replaced, in consequence of
adhesions which it may have contracted with some part of the sac, it then
becomes necessary to open this envelope. And now the position of the epigastric
artery is to be remembered, so as to avoid wounding it in the incision about to
be made through the constricted neck of the sac. The artery being situated on
the inner side of the neck of the sac of an oblique hernia, requires the
incision to be made outwards from the external side of the neck;
whereas in the direct hernia, the artery being on its outer side, the
incision should be conducted inwards from the inner side of the
neck. But as the external or oblique hernia may by its weight, in process
of time, gravitate so far inwards as to assume the position and appearance of a
hernia originally direct and internal, and as by this change of place the
oblique hernia, becoming direct as to position, does not at the same time
become internal in respect to the epigastric artery,—for this vessel, F, Plate
35, has been borne inwards to the place, G, where it still lies, internal to
the neck of the sac, and since, moreover, it is very difficult to diagnose a
case of this kind with positive certainty, it is therefore recommended to
incise the stricture at the neck of the sac in a line carried directly
upwards. (Sir Astley Cooper.) It will be seen, however, on referring to
Plates 32, 33, 34, 35, 36, 37, & 38, that an incision carried obliquely
upwards towards the umbilicus would be much more likely to avoid the
epigastric artery through all its varying relations.

DESCRIPTION OF THE FIGURES OF PLATES 35, 36, 37, & 38.

PLATE 35.

A. Anterior superior spine of the ilium; a, indicates the situation of
the middle of Poupart’s ligament.

B. Symphysis pubis.

C. Rectus abdominis muscle covered by the fascia transversalis.

D. The peritonaeum lining the groin.

E. The situation of the conjoined tendon resisting the further progress of the
external hernia gravitating inwards.

F. A dotted line indicating the original situation of the epigastric artery in
the external hernia.

G. The new position assumed by the epigastric artery borne inwards by the
weight of the old external hernia.

H. The original situation of the neck of the sac of the external hernia.

I. The new situation assumed by the neck of the sac of an old external hernia
which has gravitated inwards from its original place at H.

K. The external iliac vein covered by the peritonaeum.

L. The external iliac artery covered by the peritonaeum and crossed by the
spermatic vessels.

M. The psoas muscle supporting the spermatic vessels and the genito-crural
nerve.

N. The iliacus muscle.

O. The transversalis fascia lining the transverse muscle.

Plate 35

PLATE 36.—AN ANTERIOR VIEW OF PLATE 35.

A. Anterior superior iliac spinous process.

B. The navel.

C. The situation of the crista pubis.

D. The external oblique muscle; d, its tendon.

E. Internal oblique muscle; e, its tendon, covering the rectus muscle.

F. Lower part of the transverse muscle; f, the conjoined tendon.

G. The transversalis fascia investing the upper part of the hernial sac;
g, the original situation of the epigastric artery internal to this
hernia; g*, the new situation of the artery pushed inwards.

H. The hernial sac, invested by h, the elongation of the fascia
transversalis, or funnel-shaped sheath.

I. The femoral artery.

K. The femoral vein.

L. The sartorius muscle.

M. Iliac part of the fascia lata joining Poupart’s ligament.

N. Pubic part of the fascia lata.

O. Saphena vein.

P P. Falciform margin of the saphenous opening.

Q. See Plate 38.

R. Sheath of the femoral vessels.

S. Anterior crural nerve.

T. The external ring.

Plate 36

PLATE 37.

All the letters except the following indicate the same parts as in Plate 35.

F. The epigastric artery passing between the two hernial sacs

G. The umbilical ligament.

H. The neck of the sac of the external hernia.

I. The neck of the sac of the internal hernia.

Plate 37

PLATE 38.—AN ANTERIOR VIEW OF PLATE 37.

All the letters, with the exception of the following, refer to the same parts
as in Plate 36.

G. The funnel-shaped elongation of the fascia transversalis receiving g,
the sac of the external bubonocele.

H. The sac of the internal inguinal hernia invested by h, the
transversalis fascia.

Q. The spermatic vessels lying on the outer side of H, the direct inguinal
hernia.

Plate 38

COMMENTARY ON PLATES 39 & 40.

DEMONSTRATIONS OF THE NATURE OF CONGENITAL AND INFANTILE INGUINAL HERNIAE, AND
OF HYDROCELE.

PLATE 39. Fig. 1—The descent of the testicle from the loins to the
scrotum.—The foetal abdomen and scrotum form one general cavity, and are
composed of parts which are structurally identical. The cutaneous, fascial,
muscular, and membranous layers of the abdominal parietes are continued into
those of the scrotum. At the fifth month of foetal life, the testicle, 3, is
situated in the loins beneath the kidney, 2. The testicle is then numbered
amongst the abdominal viscera, and, like these, it is developed external to the
peritonaeal membrane, which forms an envelope for it. At the back and sides of
the testicle, where the peritonaeum is reflected from it, a small membranous
fold or mesentery (mesorchium, Seiler) is formed, and between the layers
of this the nerves and vessels enter the organ, the nerves being derived from
the neighbouring sympathetic ganglia (aortic plexus), while the arteries and
veins spring directly from the main abdominal bloodvessels. It being
predetermined that the testicle, 3, should migrate from the loins to the
scrotum, 6 a, 7, at a period included between the sixth and ninth month,
certain structural changes are at this time already effected for its sure and
easy passage. By the time that the testis, 5, is about to enter the internal
inguinal ring, 6 a, (seventh or eighth month,) a process or pouch of the
peritonaeal membrane (processus vaginalis) has already descended through this
aperture into the scrotum, and the testicle follows it.

The descent of the testis is effected by a very slow and gradual process of
change. (Tout va par degres dans la nature, et rien par sauts.—Bonnet.)
But how, or by what distinct and active structural agent, this descent is
effected, or whether there does exist, in fact, any such agent as that which
anatomists name “gubernaculum testis,” are questions which appear to me by no
means settled.[Footnote]

[Footnote:  Dr. Carpenter (Principles of Human Physiology) remarks, that
“the cause of this descent is not very clear. It can scarcely be due merely, as
some have supposed, to the contraction of the gubernaculum, since that does not
contain any fibrous structure until after the lowering of the testis has
commenced.” Dr. Sharpey (Quain’s Anatomy, 5th edition) observes, that “the
office of the gubernaculum is yet imperfectly understood.” The opinions of
these two distinguished physiologists will doubtless be regarded as an
impartial estimate of the results of the researches prosecuted in reference to
these questions by Haller, Camper, Hunter, Arnaud, Lobstein, Meckel, Paletta,
Wrisberg, Vicq d’Azyr, Brugnone, Tumiati, Seiler, Girardi, Cooper, Bell, Weber,
Carus, Cloquet, Curling, and others. From my own observations, I am led to
believe that no such muscular structure as a gubernaculum exists, and therefore
that the descent of the testis is the effect of another cause. Leaving these
matters, however, to the consideration of the physiologist, it is sufficient
for the surgeon to know that the testis in its transition derives certain
coverings from the parietes of the groin, and that a communication is thereby
established between the scrotal and abdominal cavities.]

The general lining membrane of the foetal abdomen is composed of two layers—an
outer one of fibrous, and an inner one of serous structure. Of these two
layers, the abdominal viscera form for themselves a double envelope.
[Footnote]  The testis in the loins has a covering from both membranes,
and is still found to be enclosed by both, even when it has descended to the
scrotum. The two coverings of fibro-serous structure which surrounded the
testis in the loins become respectively the tunica albuginea and tunica
vaginalis when the gland occupies the scrotal cavity.

[Footnote: Langenbeck describes the peritonaeum as consisting of two layers;
one external and fibrous, another internal and serous. By the first, he means,
I presume, that membrane of which the transversalis and iliac fasciae are
parts. (See Comment. de Periton. Structura, &c.) ]

Plate 39—Figure 1

PLATE 39, Fig. 2.—The testicle in the scrotum.—When the testicle, 5,
descends into the scrotum, 7, which happens in general at the time of birth,
the abdomino-scrotal fibro-serous membrane, 6 a, 6 d, is still
continuous at the internal ring, 6 b. From this point downwards, to a
level with the upper border of the testicle, the canal of communication between
the scrotal cavity and the abdomen becomes elongated and somewhat constricted.
At this part, the canal itself consists, like the abdominal membrane above and
the scrotal membrane below, of a fibrous and serous layer, the latter enclosed
within the former. The serous lining of this canal is destined to be
obliterated, while the outer fibrous membrane is designed to remain in its
primitive condition. When the serous canal contracts and degenerates to the
form of a simple cord, it leaves the fibrous canal still continuous above with
the fibrous membrane (transversalis fascia) of the abdomen, and below with the
fibrous envelope (tunica albuginea) of the testis; and at the adult period,
this fibrous canal is known as the internal spermatic sheath, or
infundibuliform fascia enclosing the remains of the serous canal, together with
the spermatic vessels, &c.

Plate 39—Figure 2

PLATE 39, Fig. 3.—The serous tunica vaginalis is separated from the
peritonaeum.—When the testicle, 7, has descended to the scrotum, the serous
tube or lining of the inguinal canal and cord, 6 b, 6 c, closes
and degenerates into a simple cord, (infantile spermatic cord,) and thereby the
peritonaeal sac, 6 a, becomes distinct from the serous tunica vaginalis,
6 d. But the fibrous tube, or outer envelope of the inguinal canal,
remains still pervious, and continues in this condition throughout life. In the
adult, we recognise this fibrous tube as the infundibuliform fascia of the
cord, or as forming the fascia propria of an external inguinal hernia. The
anterior part of the fibrous spermatic tube descends from the fascia
transversalis; the posterior part is continuous with the fascia iliaca. In
relation to the testicle, the posterior part will be seen to be reflected over
the body of the gland as the tunica albuginea, while the anterior part blends
with the cellular tissue of the front wall of the scrotum. The tunica
vaginalis, 6 d, is now traceable as a distinct sac,[Footnote] closed on
all sides, and reflected from the fore part of the testicle, above and below,
to the posterior aspect of the front wall of the scrotum.

[Footnote: Mr. Owen states that the Chimpanzee alone, amongst brute animals,
has the tunica vaginalis as a distinct sac.]

Plate 39—Figure 3

PLATE 40, Fig. 1.—The abdomino-scrotal serous lining remains continuous at
the internal ring, and a congenital hydrocele is formed.—When the serous
spermatic tube, 6 b, 6 c, remains pervious and continuous above
with the peritonaeum, 6 a, and below with the serous tunica vaginalis, 6
d, the serous fluid of the abdomen will naturally gravitate to the most
depending part—viz., the tunica vaginalis; and thus a hydrocele is formed. This
kind of hydrocele is named congenital, owing to the circumstance that the
natural process of obliteration, by which the peritonaeum becomes separated
from the tunica vaginalis, has been, from some cause, arrested. [Footnote
1]  As long as the canal of communication, 6 b, 6 c, between
the tunica vaginalis, 6 d, and the peritonaeum 6 a, remains
pervious, which it may be throughout life, this form of hydrocele is, of
course, liable to occur. It may be diagnosed from diseased enlargements of the
testicle, by its transparency, its fluctuation, and its smooth, uniform fulness
and shape, besides its being of less weight than a diseased testis of the same
size would be. It may be distinguished from the common form of hydrocele of the
isolated tunica vaginalis by the fact, that pressure made on the scrotum will
cause the fluid to pass freely into the general cavity of the peritonaeum. As
the fluid distends the tunica vaginalis, 6 c, 6 d, in front of
the testis, this organ will of course lie towards the back of the scrotum, and
therefore, if it be found necessary to evacuate the fluid, the puncture may be
made with most safety in front of the scrotum. If ascites should form in an
adult in whom the tunica vaginalis still communicates with the peritonaeal sac,
the fluid which accumulates in the latter membrane will also distend the
former, and all the collected fluid may be evacuated by tapping the scrotum.
When a hydrocele is found to be congenital, it must be at once obvious that to
inject irritating fluids into the tunica vaginalis (the radical cure) is
inadmissible. In an adult, free from all structural disease, and in whom a
congenital hydrocele is occasioned by the gravitation of the ordinary serous
secretion of the peritonaeum, a cure may be effected by causing the
obliteration of the serous spermatic canal by the pressure of a truss. When a
congenital hydrocele happens in an infant in whom the testicle, 5, Fig. 1,
Plate 39, is arrested in the inguinal canal, [Footnote 2] if pressure be made
on this passage with a view of causing its closure, the testicle will be
prevented from descending.

[Footnote 1: The serous spermatic tube remains open in all quadrupeds; but
their natural prone position renders them secure against hydrocele or hernial
protrusion. It is interesting to notice how in man, and the most
anthropo-morphous animals, where the erect position would subject these to the
frequent accident of hydrocele or hernia, nature causes the serous spermatic
tube to close.]

[Footnote 2: In many quadrupeds (the Rodentia and Monotremes) the testes remain
within the abdomen. In the Elephant, the testes always occupy their original
position beneath the kidneys, in the loins. Human adults are occasionally found
to be “testi-conde;” the testes being situated below the kidneys, or at some
part between this position and the internal inguinal ring. Sometimes only one
of the testes descends to the scrotum.]

Plate 40—Figure 1.

PLATE 40, Fig. 2.—The serous spermatic canal closes imperfectly, so as to
become sacculated, and thus a hydrocele of the cord is formed.—After the
testicle, 7, has descended to the scrotum, the sides of the serous tube, or
lining of the inguinal canal and cord, 6 b, 6 c, may become
adherent at intervals; and the intervening sacs of serous membrane continuing
to secrete their proper fluid, will occasion a hydrocele of the cord. This form
of hydrocele will differ according to the varieties in the manner of closure;
and these may take place in the following modes:—1st, if the serous tube close
only at the internal ring, 6 a, while the lower part of it, 6 b,
6 c, remains pervious, and communicating with the tunica vaginalis, 6
d, a hydrocele will be formed of a corresponding shape; 2nd, if the tube
close at the upper part of the testicle, 6 c, thus isolating the tunica
vaginalis, 6 d, while the upper part, 6 b, remains pervious, and
the internal ring, 6 a, open, and communicating with the peritonaeal
sac, a hydrocele of the cord will happen distinct from the tunica vaginalis; or
this latter may be, at the same time, distended with fluid, if the disposition
of the subject be favourable to the formation of dropsy; 3rd, the serous tube
may close at the internal ring, form sacculi along the cord, and close again at
the top of the testicle, thus separating the tunica vaginalis from the abdomen,
and thereby several isolated hydroceles may be formed. If in this condition of
the parts we puncture one of the sacs for the evacuation of its contents, the
others, owing to their separation, will remain distended.

Plate 40—Figure 2.

PLATE 40, Fig. 3.—Hydrocele of the isolated tunica vaginalis.—When the
serous spermatic tube, 6 b, 6 c, becomes obliterated, according
to the normal rule, after the descent of the testicle, 7, the tunica vaginalis,
6 d, is then a distinct serous sac. If a hydrocele form in this sac, it
may be distinguished from the congenital variety by its remaining undiminished
in bulk when the subject assumes the horizontal position, or when pressure is
made on the tumour, for its contents cannot now be forced into the abdomen. The
testicle, 7, holds the same position in this as it does in the congenital
hydrocele. [Footnote] The radical cure may be performed here without
endangering the peritonaeal sac. Congenital hydrocele is of a cylindrical
shape; and this is mentioned as distinguishing it from isolated hydrocele of
the tunica vaginalis, which is pyriform; but this mark will fail when the cord
is at the same time distended, as it may be, in the latter form of the
complaint.

[Footnote: When a hydrocele is interposed between the eye and a strong light,
the testis appears as an opaque body at the back of the tunica vaginalis. But
this position of the organ is, from several causes, liable to vary. The testis
may have become morbidly adherent to the front wall of the serous sac, in which
case the hydrocele will distend the sac laterally. Or the testis may be so
transposed in the scrotum, that, whilst the gland occupies its front part, the
distended tunica vaginalis is turned behind. The tunica vaginalis, like the
serous spermatic tube, may, in consequence of inflammatory fibrinous effusion,
become sacculated-multilocular, in which case, if a hydrocele form, the
position of the testis will vary accordingly.—See Sir Astley Cooper’s work,
(“Anatomy and Diseases of the Testis;”) Morton’s “Surgical Anatomy;” Mr.
Curling’s “Treatise on Diseases of the Testis;” and also his article
“Testicle,” in the Cyclopaedia of Anatomy and Physiology.]

Plate 40—Figure 3.

PLATE 40, Fig. 4.—The serous spermatic tube remaining pervious, a congenital
hernia is formed.—When the testicle, 7, has descended to the scrotum, if
the communication between the peritonaeum, 6 a, and the tunica
vaginalis, 6 c, be not obliterated, a fold of the intestine, 13, will
follow the testicle, and occupy the cavity of the tunica vaginalis, 6 d.
In this form of hernia (hernia tunicae vaginalis, Cooper), the intestine
is in front of, and in immediate contact with, the testicle. The intestine may
descend lower than the testicle, and envelope this organ so completely as to
render its position very obscure to the touch. This form of hernia is named
congenital, since it occurs in the same condition of the parts as is found in
congenital hydrocele—viz., the inguinal ring remaining unclosed. It may occur
at any period of life, so long as the original congenital defect remains. It
may be distinguished from hydrocele by its want of transparency and
fluctuation. The impulse which is communicated to the hand applied to the
scrotum of a person affected with scrotal hernia, when he is made to cough, is
also felt in the case of congenital hydrocele. But in hydrocele of the separate
tunica vaginalis, such impulse is not perceived. Congenital hernia and
hydrocele may co-exist; and, in this case, the diagnostic signs which are
proper to each, when occurring separately, will be so mingled as to render the
precise nature of the case obscure.

Plate 40—Figure 4.

PLATE 40, Fig. 5.—Infantile hernia.—When the serous spermatic tube
becomes merely closed, or obliterated at the inguinal ring, 6 b, the
lower part of it, 6 c, is pervious, and communicating with the tunica
vaginalis, 6 d. In consequence of the closure of the tube at the
inguinal ring, if a hernia now occur, it cannot enter the tunica vaginalis, and
come into actual contact with the testicle. The hernia, 13, therefore, when
about to force the peritonaeum, 6 a, near the closed ring, 6 b,
takes a distinct sac or investment from this membrane. This hernial sac, 6
e, will vary as to its position in regard to the tunica vaginalis, 6
d, according to the place whereat it dilates the peritonaeum at the
ring. The peculiarity of this hernia, as distinguished from the congenital
form, is owing to the scrotum containing two sacs,—the tunica vaginalis and the
proper sac of the hernia; whereas, in the congenital variety, the tunica
vaginalis itself becomes the hernial sac by a direct reception of the naked
intestine. If in infantile hernia a hydrocele should form in the tunica
vaginalis, the fluid will also distend the pervious serous spermatic tube, 6
c, as far up as the closed internal ring, 6 b, and will thus
invest and obscure the descending herniary sac, 13. This form of hernia is
named infantile (Hey), owing to the congenital defect in that process,
whereby the serous tube lining the cord is normally obliterated. Such a form of
hernia may occur at the adult age for the first time, but it is still the
consequence of original default.

Plate 40—Figure 5.

PLATE 40, Fig. 6.—Oblique inguinal hernia in the adult.—This variety of
hernia occurs not in consequence of any congenital defect, except inasmuch as
the natural weakness of the inguinal wall opposite the internal ring may be
attributed to this cause. The serous spermatic tube has been normally
obliterated for its whole length between the internal ring and the tunica
vaginalis; but the fibrous tube, or spermatic fascia, is open at the internal
ring where it joins the transversalis fascia, and remains pervious as far down
as the testicle. The intestine, 13, forces and distends the upper end of the
closed serous tube; and as this is now wholly obliterated, the herniary sac, 6
c, derived anew from the inguinal peritonaeum, enters the fibrous tube,
or sheath of the cord, and descends it as far as the tunica vaginalis, 6
d, but does not enter this sac, as it is already closed. When we compare
this hernia, Fig. 6, Plate 40, with the infantile variety, Fig. 5, Plate 40, we
find that they agree in so far as the intestinal sac is distinct from the
tunica vaginalis; whereas the difference between them is caused by the fact of
the serous cord remaining in part pervious in the infantile hernia; and on
comparing Fig. 6, Plate 40, with the congenital variety, Fig. 4, Plate 40, we
see that the intestine has acquired a new sac in the former, whereas, in the
latter, the intestine has entered the tunica vaginalis. The variable position
of the testicle in Figs. 4, 5, & 6, Plate 40, is owing to the variety in
the anatomical circumstances under which these herniae have happened.

Plate 40—Figure 6.

COMMENTARY ON PLATES 41 & 42.

DEMONSTRATIONS OF THE ORIGIN AND PROGRESS OF INGUINAL HERNIAE IN GENERAL.

PLATE 41, Fig. 1.—When the serous spermatic tube is obliterated for its whole
length between the internal ring, 1, and the top of the testicle, 13, a hernia,
in order to enter the inguinal canal, 1, 4, must either rupture the peritonaeum
at the point 1, or dilate this membrane before it in the form of a sac.
[Footnote] If the peritonaeum at the point 1 be ruptured by the intestine, this
latter will enter the fibrous spermatic tube, 2, 3, and will pass along this
tube devoid of the serous sac. If, on the other hand, the intestine dilates the
serous membrane at the point, 1, where it stretches across the internal ring,
it will, on entering the fibrous tube, (infundibuliform fascia,) be found
invested by a sac of the peritonaeum, which it dilates and pouches before
itself. As the epigastric artery, 9, bends in general along the internal border
of the ring of the fibrous tube, 2, 2, the neck of the hernial sac which enters
the ring at a point external to the artery must be external to it, and remain
so despite all further changes in the form, position, and dimensions of the
hernia. And as this hernia enters the ring at a point anterior to the spermatic
vessels, its neck must be anterior to them. Again, if the bowel be invested by
a serous sac, formed of the peritonaeum at the point 1, the neck of such sac
must intervene between the protruding bowel and the epigastric and spermatic
vessels. But if the intestine enter the ring of the fibrous tube, 2, 2, by
having ruptured the peritonaeum at the point 1, then the naked intestine will
lie in immediate contact with these vessels.

[Footnote: Mr. Lawrence (op. cit.) remarks, “When we consider the texture of
the peritonaeum, and the mode of its connexion to the abdominal parietes, we
cannot fancy the possibility of tearing the membrane by any attitude or
motion.” Cloquet and Scarpa have also expressed themselves to the effect, that
the peritonaeum suffers a gradual distention before the protruding bowel.]

Plate 41—Figure 1

PLATE 41, Fig. 2—When the serous spermatic tube, 11, remains pervious between
the internal ring, 1, (where it communicates with the general peritonaeal
membrane,) and the top of the testicle, (where it opens into the tunica
vaginalis,) the bowel enters this tube directly, without a rupture of the
peritonaeum at the point 1. This tube, therefore, becomes one of the
investments of the bowel. It is the serous sac, not formed by the protruding
bowel, but one already open to receive the bowel. This is the condition
necessary to the formation of congenital hernia. This hernia must be one of the
external oblique variety, because it enters the open abdominal end of the
infantile serous spermatic tube, which is always external to the epigastric
artery. Its position in regard to the spermatic vessels is the same as that
noticed in Fig, 1, Plate 41. But, as the serous tube through which the
congenital hernia descends, still communicates with the tunica vaginalis, so
will this form of hernia enter this tunic, and thereby become different to all
other herniae, forasmuch as it will lie in immediate contact with the testicle.
[Footnote]

[Footnote: A hernia may be truly congenital, and yet the intestine may not
enter the tunica vaginalis. Thus, if the serous spermatic tube close only at
the top of the testicle, the bowel which traverses the open internal inguinal
ring and pervious tube will not enter the tunica vaginalis.]

Plate 41—Figure 2

PLATE 41, Fig. 3.—The infantile serous spermatic tube, 11, sometimes remains
pervious in the neighbourhood of the internal ring, 1, and a narrow tapering
process of the tube (the canal of Nuck) descends within the fibrous tube, 2, 3,
and lies in front of the spermatic vessels and epigastric artery. Before this
tube reaches the testicle, it degenerates into a mere filament, and thus the
tunica vaginalis has become separated from it as a distinct sac. When the bowel
enters the open abdominal end of the serous tube, this latter becomes the
hernial sac. It is not possible to distinguish by any special character a
hernia of this nature, when already formed, from one which occurs in the
condition of parts proper to Fig. 1, Plate 41, or that which is described in
the note to Fig. 2, Plate 41; for when the intestine dilates the tube, 11, into
the form of a sac, this latter assumes the exact shape of the sac, as noticed
in Fig. 1, Plate 41. The hernia in question cannot enter the tunica vaginalis.
Its position in regard to the epigastric and spermatic vessels is the same as
that mentioned above.

Plate 41—Figure 3

PLATE 41, Fig. 4.—If the serous spermatic tube, 11, be obliterated or closed at
the internal ring, 1, thus cutting off communication with the general
peritonaeal membrane; and if, at the same time, it remain pervious from this
point above to the tunica vaginalis below, then the herniary bowel, when about
to protrude at the point 1, must force and dilate the peritonaeum, in order to
form its sac anew, as stated of Fig. 1, Plate 41. Such a hernia does not enter
either the serous tube or the tunica vaginalis; but progresses from the point
1, in a distinct sac. In this case, there will be found two sacs—one enclosing
the bowel; and another, consisting of the serous spermatic tube, still
continuous with the tunica vaginalis. This original state of the parts may,
however, suffer modification in two modes: 1st, if the bowel rupture the
peritonaeum at the point 1, it will enter the serous tube 11, and descend
through this into the cavity of the tunica vaginalis, as in the congenital
variety. 2nd, if the bowel rupture the peritonaeum near the point 1, and does
not enter the serous tube 11, nor the tunica vaginalis, then the bowel will be
found devoid of a proper serous sac, while the serous tube and tunica vaginalis
still exist in communication. In either case, the hernia will hold the same
relative position in regard to the epigastric artery and spermatic vessels, as
stated of Fig. 1, Plate 41.

Plate 41—Figure 4

PLATE 41, Fig. 5.—Sudden rupture of the peritonaeum at the closed internal
serous ring, 1, though certainly not impossible, may yet be stated as the
exception to the rule in the formation of an external inguinal hernia. The
aphorism, “natura non facit saltus,” is here applicable. When the peritonaeum
suffers dilatation at the internal ring, 1, it advances gradatim and
pari passu with the progress of the protruding bowel, and assumes the
form, character, position, and dimensions of the inverted curved phases, marked
11, 11, till, from having at first been a very shallow pouch, lying external to
the epigastric artery, 9, it advances through the inguinal canal to the
external ring, 4, and ultimately traverses this aperture, taking the course of
the fibrous tube, 3, down to the testicle in the scrotum.

Plate 41—Figure 5

PLATE 41, Fig. 6.—When the bowel dilates the peritonaeum opposite the internal
ring, and carries a production of this membrane before it as its sac, then the
hernia will occupy the inguinal canal, and become invested by all those
structures which form the canal. These structures are severally infundibuliform
processes, so fashioned by the original descent of the testicle; and,
therefore, as the bowel follows the track of the testicle, it becomes, of
course, invested by the selfsame parts in the selfsame manner. Thus, as the
infundibuliform fascia, 2, 3, contains the hernia and spermatic vessels, so
does the cremaster muscle, extending from the lower margins of the internal
oblique and transversalis, invest them also in an infundibuliform manner.
[Footnote]

[Footnote: Much difference of opinion prevails as to the true relation which
the cord (and consequently the oblique hernia) bears to the lower margins of
the oblique and transverse muscles, and their cremasteric prolongation. Mr.
Guthrie (Inguinal and Femoral Hernia) has shown that the fibres of the
transversalis, as well as those of the internal oblique, are penetrated by the
cord. Albinus, Haller, Cloquet, Camper, and Scarpa, record opinions from which
it may be gathered that this disposition of the parts is (with some exceptions)
general. Sir Astley Cooper describes the lower edge of the transversalis as
curved all round the internal ring and cord. From my own observations, coupled
with these, I am inclined to the belief that, instead of viewing these facts as
isolated and meaningless particulars, we should now fuse them into the one idea
expressed by the philosophic Carus, and adopted by Cloquet, that the cremaster
is a production of the abdominal muscles, formed mechanically by the testicle,
which in its descent dilates, penetrates, and elongates their fibres.]

Plate 41—Figure 6

PLATE 41. Fig. 7.—When an external inguinal hernia, 11, dilates and protrudes
the peritonaeum from the closed internal ring, 1, and descends the inguinal
canal and fibrous tube, 3, 3, it imitates, in most respects, the original
descent of the testicle. The difference between both descents attaches alone to
the mode in which they become covered by the serous membrane; for the testicle
passes through the internal ring behind the inguinal peritonaeum, at the
same time that it takes a duplicature of this membrane; whereas the bowel
encounters this part of the peritonaeum from within, and in this mode
becomes invested by it on all sides. This figure also represents the form and
relative position of a hernia, as occurring in Figs. 1 and 3, 5, and 6, Plate
41.

Plate 41—Figure 7

PLATE 41, Fig. 8.—When the serous spermatic tube only closes at the internal
ring, as seen at 1, Fig. 4, Plate 41, if a hernia afterwards pouch the
peritonaeum at this part, and enter the inguinal canal, we shall then have the
form of hernia, Fig. 8, Plate 41, termed infantile. Two serous sacs will be
here found, one within the cord, 13, and communicating with the tunica
vaginalis, the other, 11, containing the bowel, and being received by inversion
into the upper extremity of the first. Thus the infantile serous canal, 13,
receives the hernial sac, 11. The inguinal canal and cord may become
multicapsular, as in Fig. 8, from various causes, each capsule being a distinct
serous membrane. First, independent of hernial formation, the original serous
tube may become interruptedly obliterated, as in Plate 40, Fig. 2. Secondly,
these sacs may persist to adult age, and have a hernial sac added to their
number, whatever this may be. Thirdly, the original serous tube, 13, Fig. 8,
may persist, and after having received the hernial sac, 11, the bowel may have
been reduced, leaving its sac behind it in the inguinal canal; the neck of this
sac may have been obliterated by the pressure of a truss, a second hernia may
protrude at the point 1, and this may be received into the first hernial sac in
the same manner as the first was received into the original serous infantile
tube. The possibility of these occurrences is self-evident, even if they were
never as yet experienced. [Footnote]

[Footnote: According to Mr. Lawrence and M. Cloquet, most of the serous cysts
found around hernial tumours are ancient sacs obliterated at the neck, and
adhering to the new swelling (opera cit.)]

Plate 41—Figure 8

PLATE 42, Fig. 1.—The epigastric artery, 9, being covered by the fascia
transversalis, can lend no support to the internal ring, 2, 2, nor to the tube
prolonged from it. The herniary bowel may, therefore, dilate the peritonaeum
immediately on the inner side of the artery, and enter the inguinal canal. In
this way the hernia, 11, although situated internal to the epigastric artery,
assumes an oblique course through the canal, and thus closely simulates the
external variety of inguinal hernia, Fig. 7, Plate 41. If the hernia enter the
canal, as represented in Fig. 1, Plate 42, it becomes invested by the same
structures, and assumes the same position in respect to the spermatic vessels,
as the external hernia.

Plate 42—Figure 1

PLATE 42, Fig. 2.—The hernial sac, 11, which entered the ring of the fibrous
tube, 2, 2, at a point immediately internal to the epigastric artery, 9, may,
from having been at first oblique, as in Fig. 1, Plate 42, assume a direct
position. In this case, the ring of the fibrous tube, 2, 2, will be much
widened; but the artery and spermatic vessels will remain in their normal
position, being in no wise affected by the gravitating hernia. If the conjoined
tendon, 6, be so weak as not to resist the gravitating force of the hernia, the
tendon will become bent upon itself. If the umbilical cord, 10, be side by side
with the epigastric artery at the time that the hernia enters the mouth of the
fibrous tube, then, of course, the cord will be found external. If the cord lie
towards the pubes, apart from the vessel, the hernia may enter the fibrous tube
between the cord, 10, and artery, 9. [Footnote:] It is impossible for any
internal hernia to assume the congenital form, because the neck of the original
serous spermatic tube, 11, Fig. 2, Plate 41, being external to the epigastric
artery, 9, cannot be entered by the hernia, which originates internally to this
vessel.

[Footnote: M. Cloquet states that the umbilical cord is always found on the
inner side of the external hernia. Its position varies in respect to the
internal hernia, (op. cit. prop. 52.)]

Plate 42—Figure 2

PLATE 42, Fig. 3.—Every internal hernia, which does not rupture the
peritonaeum, carries forward a sac produced anew from this membrane, whether
the hernia enter the inguinal canal or not. But this is not the case with
respect to the fibrous membrane which forms the fascia propria. If the hernia
enter the inguinal wall immediately on the inner side of the epigastric artery,
Fig. 1, Plate 42, it passes direct into the ring of the fibrous tube, 2, 2,
already prepared to receive it. But when the hernia, 11, Fig. 3, Plate 42,
cleaves the conjoined tendon, 6, 6, then the artery, 9, and the tube, 2, 2,
remain in their usual position, while the bowel carries forward a new
investment from the transversalis fascia, 5, 5. That part of the conjoined
tendon which stands external to the hernia keeps the tube, 2, 2, in its proper
place, and separates it from the fold of the fascia which invests the hernial
sac. This is the only form in which an internal hernia can be said to be
absolutely distinct from the inguinal canal and spermatic vessels. This hernia,
when passing the external ring, 4, has the spermatic cord on its outer side.

Plate 42—Figure 3

PLATE 42, Fig. 4.—The external hernia, from having been originally oblique, may
assume the position of a hernia originally internal and direct. The change of
place exhibited by this form of hernia does not imply a change either in its
original investments or in its position with respect to the epigastric artery
and spermatic vessels. The change is merely caused by the weight and
gravitation of the hernial mass, which bends the epigastric artery, 9*, from
its first position on the inner margin of the internal ring, 1, till it assumes
the place 9. In consequence of this, the internal ring of the fascia
transversalis, 2, 2, is considerably widened, as it is also in Fig. 2, Plate
42. It is the inner margin of the fibrous ring which has suffered the pressure;
and thus the hernia now projects directly from behind forwards, through, 4, the
external ring. The conjoined tendon, 6, when weak, becomes bent upon itself.
The change of place performed by the gravitating hernia may disturb the order
and relative position of the spermatic vessels; but these, as well as the
hernia, still occupy the inguinal canal, and are invested by the spermatic
fascia, 3, 3. When an internal hernia, Fig. 1, Plate 42, enters the inguinal
canal, it also may descend the cord as far as the testicle, and assume in
respect to this gland the same position as the external hernia. [Footnote]

[Footnote: As the external hernia, Fig. 4, Plate 42, may displace the
epigastric artery inwards, so may the internal hernia, Fig. 1, Plate 42,
displace the artery outwards. Mr. Lawrence, Sir Astley Cooper, Scarpa,
Hesselbach, and Langenbeck, state, however, that the internal hernia does not
disturb the artery from its usual position three-fourths of an inch from the
external ring.]

Plate 42—Figure 4

PLATE 42, Figs. 5, 6, 7.—The form and position of the inguinal canal varies
according to the sex and age of the individual. In early life, Fig. 6, the
internal ring is situated nearly opposite to the external ring, 4. As the
pelvis widens gradually in the advance to adult age, Fig. 5, the canal becomes
oblique as to position. This obliquity is caused by a change of place,
performed rather by the internal than the external ring. [Footnote] The greater
width of the female pelvis than of the male, renders the canal more oblique in
the former; and this, combined with the circumstance that the female inguinal
canal, Fig. 7, merely transmits the round ligament, 14, accounts anatomically
for the fact, that this sex is less liable to the occurrence of rupture in this
situation.

[Footnote: M. Velpeau (Nouveaux Elemens de med. Operat.) states the length of
the inguinal canal in a well-formed adult, measured from the internal to the
external ring, to be 1-1/2 or 2 inches, and 3 inches including the rings; but
that in some individuals the rings are placed nearly opposite; whilst in young
subjects the two rings nearly always correspond. When, in company with these
facts, we recollect how much the parts are liable to be disturbed in ruptures,
it must be evident that their relative position cannot be exactly ascertained
by measurement, from any given point whatever. The judgment alone must fix the
general average.]

Plate 42—Figure 5

Plate 42—Figure 6

Plate 42—Figure 7

COMMENTARY ON PLATES 43 & 44.

THE DISSECTION OF FEMORAL HERNIA, AND THE SEAT OF STRICTURE.

Whilst all forms of inguinal herniae escape from the abdomen at places situated
immediately above Poupart’s ligament, the femoral hernia, G, Fig. 1, Plate 43,
is found to pass from the abdomen immediately below this structure, A I, and
between it and the horizontal branch of the pubic bone. The inguinal canal and
external abdominal ring are parts concerned in the passage of inguinal herniae,
whether oblique or direct, external or internal; whilst the femoral canal and
saphenous opening are the parts through which the femoral hernia passes. Both
these orders of parts, and of the herniae connected with them respectively,
are, however, in reality situated so closely to each other in the
inguino-femoral region, that, in order to understand either, we should, examine
both at the same time comparatively.

The structure which is named Poupart’s ligament in connexion with inguinal
herniae, is named the femoral or crural arch (Gimbernat) in relation to femoral
hernia. The simple line, therefore, described by this ligament explains the
narrow interval which separates both varieties of the complaint. So small is
the line of separation described between these herniae by the ligament, that
this (so to express the idea) stands in the character of an arch, which, at the
same time, supports an aqueduct (the inguinal canal) and spans a road (the
femoral sheath.) The femoral arch, A I, Fig. 1, Plate 43, extends between the
anterior superior iliac spinous process and the pubic spine. It connects the
aponeurosis of the external oblique muscle, D d, Fig. 2, Plate 44, with
F, the fascia lata. Immediately above and below its pubic extremity appear the
external ring and the saphenous opening. On cutting through the falciform
process, F, Fig. 1, Plate 44, we find Gimbernat’s ligament, R, a structure well
known in connexion with femoral hernia. Gimbernat’s ligament consists of
tendinous fibres which connect the inner end of the femoral arch with the
pectineal ridge of the os pubis. The shape of the ligament is acutely
triangular, corresponding to the form of the space which it occupies. Its apex
is internal, and close to the pubic spine; its base is external, sharp and
concave, and in apposition with the sheath of the femoral vessels. It measures
an inch, more or less, in width, and it is broader in the male than in the
female—a fact which is said to account for the greater frequency of femoral
hernia in the latter sex than in the former, (Monro.) Its strength and density
also vary in different individuals. It is covered anteriorly by, P, Fig. 1,
Plate 44, the upper cornu of the falciform process; and behind, it is in
connexion with, k, the conjoined tendon. This tendon is inserted with
the ligament into the pectineal ridge. The falciform process also blends with
the ligament; and thus it is that the femoral hernia, when constricted by
either of these three structures, may well be supposed to suffer pressure from
the three together.

A second or deep femoral arch is occasionally met with. This structure consists
of tendinous fibres, lying deeper than, but parallel with, those of the
superficial arch. The deep arch spans the femoral sheath more closely than the
superficial arch, and occupies the interval left between the latter and the
sheath of the vessels. When the deep arch exists, its inner end blends with the
conjoined tendon and Gimbernat’s ligament, and with these may also constrict
the femoral hernia.

The sheath, e f, of the femoral vessels, E F, Fig. 1, Plate 43, passes
from beneath the middle of the femoral arch. In this situation, the iliac part
of the fascia lata, F G, Fig. 2, Plate 44, covers the sheath. Its inner side is
bounded by Gimbernat’s ligament, R, Fig. 1, Plate 44, and F, the falciform edge
of the saphenous opening. On its outer side are situated the anterior crural
nerve, and the femoral parts of the psoas and iliacus muscles. Of the three
compartments into which the sheath is divided by two septa in its interior, the
external one, E, Fig. 1, Plate 43, is occupied by the femoral artery; the
middle one, F, by the femoral vein; whilst the inner one, G, gives passage to
the femoral lymphatic vessels; and occasionally, also, a lymphatic body is
found in it. The inner compartment, G, is the femoral canal, and through it the
femoral hernia descends from the abdomen to the upper and forepart of the
thigh. As the canal is the innermost of the three spaces inclosed by the
sheath, it is that which lies in the immediate neighbourhood of the saphenous
opening, Gimbernat’s ligament, and the conjoined tendon, and between these
structures and the femoral vein.

The sheath of the femoral vessels, like that of the spermatic cord, is
infundibuliform. Both are broader at their abdominal ends than elsewhere. The
femoral sheath being broader above than below, whilst the vessels are of a
uniform diameter, presents, as it were, a surplus space to receive a hernia
into its upper end. This space is the femoral or crural canal. Its abdominal
entrance is the femoral or crural ring.

The femoral ring, H, Fig. 2, Plate 43, is, in the natural state of the parts,
closed over by the peritonaeum, in the same manner as this membrane shuts the
internal inguinal ring. There is, however, corresponding to each ring, a
depression in the peritonaeal covering; and here it is that the bowel first
forces the membrane and forms of this part its sac.

On removing the peritonaeum from the inguinal wall on the inner side of the
iliac vessels, K L, we find the horizontal branch of the os pubis, and the
parts connected with it above and below, to be still covered by what is called
the subserous tissue. The femoral ring is not as yet discernible on the inner
side of the iliac vein, K; for the subserous tissue being stretched across this
aperture masks it. The portion of the tissue which closes the ring is named the
crural septum, (Cloquet.) When we remove this part, we open the femoral ring
leading to the corresponding canal. The ring is the point of union between the
fibrous membrane of the canal and the general fibrous membrane which lines the
abdominal walls external to the peritonaeum. This account of the continuity
between the canal and abdominal fibrous membrane equally applies to the
connexion existing between the general sheath of the vessels and the abdominal
membrane. The difference exists in the fact, that the two outer compartments of
the sheath are occupied by the vessels, whilst the inner one is vacant. The
neck or inlet of the hernial sac, H, Fig. 2, Plate 43, exactly represents the
natural form of the crural ring, as formed in the fibrous membrane external to,
or (as seen in this view) beneath the peritonaeum.

The femoral ring, H, is girt round on all sides by a dense fibrous circle, the
upper arc being formed by the two femoral arches; the outer arc is represented
by the septum of the femoral sheath, which separates the femoral vein from the
canal; the inner arc is formed by the united dense fibrous bands of the
conjoined tendon and Gimbernat’s ligament; and the inferior arc is formed by
the pelvic fascia where this passes over the pubic bone to unite with the under
part of the femoral canal and sheath. The ring thus bound by dense resisting
fibrous structure, is rendered sharp on its pubic and upper sides by the
salient edges of the conjoined tendon and Gimbernat’s ligament, &c. From
the femoral ring the canal extends down the thigh for an inch and a-half or two
inches in a tapering form, supported by the pectineus muscle, and covered by
the iliac part of the fascia lata. It lies side by side with the saphenous
opening, but does not communicate with this place. On a level with the lower
cornu of the saphenous opening, the walls of the canal become closely applied
to the femoral vessels, and here it may be said to terminate.

The bloodvessels which pass in the neighbourhood of the femoral canal are, 1st.
the femoral vein, F, Fig. 1, Plate 43, which enclosed in its proper sheath lies
parallel with and close to the outer side of the passage. 2nd, Within the
inguinal canal above are the spermatic vessels, resting on the upper surface of
the femoral arch, which alone separates them from the upper part or entrance of
the femoral canal. 3rd, The epigastric artery, F, Fig. 2, Plate 43, which
passes close to the outer and upper border of, H, the femoral ring. This vessel
occasionally gives off the obturator artery, which, when thus derived, will be
found to pass towards the obturator foramen, in close connexion with the ring;
that is, either descending by its outer border, G*, between this point and the
iliac vein, K; or arching the ring, G, so as to pass down close to its inner or
pubic border. In some instances, the vessel crosses the ring; a vein generally
accompanies the artery. These peculiarities in the origin and course of the
obturator artery, especially that of passing on the pubic side of the ring,
behind Gimbernat’s ligament and the conjoined tendon, E H, are fortunately very
rare.

As the course to be taken by the bowel, when a femoral hernia is being formed,
is through the crural ring and canal, the structures which have just now been
enumerated as bounding this passage, will, of course, hold the like relation to
the hernia. The manner in which a femoral hernia is formed, and the way in
which it becomes invested in its descent, may be briefly stated thus: The bowel
first dilates the peritonaeum opposite the femoral ring, H, Fig. 2, Plate 43,
and pushes this membrane before it into the canal. This covering is the hernial
sac. The crural septum has, at the same time, entered the canal as a second
investment of the bowel. The hernia is now enclosed by the sheath, G, Fig. 1,
Plate 43, of the canal itself. [Footnote 1] Its further progress through the
saphenous opening, B F, Fig. 1, Plate 44, must be made either by rupturing the
weak inner wall of the canal, or by dilating this part; in one or other of
these modes, the herniary sac emerges from the canal through the saphenous
opening. In general, it dilates the side of the canal, and this becomes the
fascia propria, B G. If it have ruptured the canal, the hernial sac appears
devoid of this covering. In either case, the hernia, increasing in size, turns
up over the margin of F, the falciform process, [Footnote 2] and ultimately
rests upon the iliac fascia lata, below the pubic third of Poupart’s ligament.
Sometimes the hernia rests upon this ligament, and simulates, to all outward
appearance, an oblique inguinal hernia. In this course, the femoral hernia will
have its three parts—neck, body, and fundus—forming nearly right angles with
each other: its neck [Footnote 3] descends the crural canal, its body is
directed to the pubis through the saphenous opening, and its fundus is turned
upwards to the femoral arch.

[Footnote 1: The sheath of the canal, together with the crural septum,
constitutes the “fascia propria” of the hernia (Sir Astley Cooper). Mr.
Lawrence denies the existence of the crural septum.]

[Footnote 2: The “upper cornu of the saphenous opening,” the “falciform
process” (Burns), and the “femoral ligament” (Hey), are names applied to the
same part. With what difficulty and perplexity does this impenetrable fog of
surgical nomenclature beset the progress of the learner!]

[Footnote 3: The neck of the sac at the femoral ring lies very deep, in the
undissected state of the parts (Lawrence).]

The crural hernia is much more liable to suffer constriction than the inguinal
hernia. The peculiar sinuous course which the former takes from its point of
origin, at the crural ring, to its place on Poupart’s ligament, and the
unyielding fibrous structures which form the canal through which it passes,
fully account for the more frequent occurrence of this casualty. The neck of
the sac may, indeed, be supposed always to suffer more or less constriction at
the crural ring. The part which occupies the canal is also very much
compressed; and again, where the hernia turns over the falciform process, this
structure likewise must cause considerable compression on the bowel in the sac.
[Footnote] This hernia suffers stricture of the passive kind always; for the
dense fibrous bands in its neighbourhood compress it rather by withstanding the
force of the herniary mass than by reacting upon it. There are no muscular
fibres crossing the course of this hernia; neither are the parts which
constrict it likely to change their original position, however long it may
exist. In the inguinal hernia, the weight of the mass may in process of time
widen the canal by gravitating; but the crural hernia, resting on the pubic
bone, cannot be supposed to dilate the crural ring, however greatly the
protrusion may increase in size and weight.

[Footnote: Sir A. Cooper (Crural Hernia) is of opinion that the stricture is
generally in the neck of the sheath. Mr. Lawrence remarks, “My own observations
of the subject have led me to refer the cause of stricture to the thin
posterior border (Gimbernat’s ligament) of the crural arch, at the part where
it is connected to the falciform process.” (Op. cit.) This statement agrees
also with the experience of Hey, (Practical Obs.)]

DESCRIPTION OF THE FIGURES OF PLATES 43 & 44.

PLATE 43.

FIGURE 1.

A. Anterior superior iliac spine.

B. Iliacus muscle, cut.

C. Anterior crural nerve, cut.

D. Psoas muscle, cut.

E. Femoral artery enclosed in e, its compartment of the femoral sheath.

F. Femoral vein in its compartment, f, of the femoral sheath.

G. The fascia propria of the hernia; g, the contained sac.

H. Gimbernat’s ligament.

I. Round ligament of the uterus.

Plate 43.—Figure 1.

FIGURE 2.

A. Anterior superior iliac spine.

B. Symphysis pubis.

C. Rectus abdominis muscle.

D. Peritonaeum.

E. Conjoined tendon.

F. Epigastric artery.

G* G. Positions of the obturator artery when given off from the epigastric.

H. Neck of the sac of the crural hernia.

I. Round ligament of the uterus.

K. External iliac vein.

L. External iliac artery.

M. Tendon of the psoas parvus muscle, resting on the psoas magnus.

N. Iliacus muscle.

O. Transversalis fascia.

Plate 43.—Figure 2.

PLATE 44.

FIGURE 1.

A. Anterior superior iliac spine.

B. The crural hernia.

C. Round ligament of the uterus.

D. External oblique muscle; d, Fig. 2, its aponeurosis.

E. Saphaena vein.

F. Falciform process of the saphenous opening.

G. Femoral artery in its sheath.

H. Femoral vein in its sheath.

I. Sartorius muscle.

K. Internal oblique muscle; k, conjoined tendon.

L L. Transversalis fascia.

M. Epigastric artery.

N. Peritonaeum.

O. Anterior crural nerve.

P. The hernia within the crural canal.

Q Q. Femoral sheath.

R. Gimbernat’s ligament.

FIGURE 2.

The other letters refer to the same parts as seen in Fig. 1.

G. Glands in the neighbourhood of Poupart’s ligament.

H. Glands in the neighbourhood of the saphenous opening.

I. The sartorius muscle seen through its fascia.

Plate 44.—Figure 1, 2.

COMMENTARY ON PLATES 45 & 46.

DEMONSTRATIONS OF THE ORIGIN AND PROGRESS OF FEMORAL HERNIA— ITS DIAGNOSIS, THE
TAXIS, AND THE OPERATION.

PLATE 45, Fig. 1.—The point, 3, from which an external inguinal hernia first
progresses, and the part, 5, within which the femoral hernia begins to be
formed, are very close to each other. The inguinal hernia, 3, arising above, 5,
the crural arch, descends the canal, 3, 3, under cover of the aponeurosis of
the external oblique muscle, obliquely downwards and inwards till it gains the
external abdominal ring formed in the aponeurosis, and thence descends to the
scrotum. The femoral hernia, commencing on a level with, 5, the femoral arch,
descends the femoral canal, under cover of the fascia lata, and appears on the
upper and forepart of the thigh at the saphenous opening, 6, 7, formed in the
fascia lata; and thence, instead of descending to the scrotum, like the
inguinal hernia, turns, on the contrary, up over the falciform process, 6, till
its fundus rests near, 5, the very place beneath which it originated. Such are
the peculiarities in the courses of these two hernial; and they are readily
accounted for by the anatomical relations of the parts concerned.

Plate 45.—Figure 1

PLATE 45, Fig. 2.—There exists a very evident analogy between the canals
through which both herniae pass. The infundibuliform fascia, 3, 3, of the
spermatic vessels is like the infundibuliform sheath, 9, 9, of the femoral
vessels. Both sheaths are productions of the general fibrous membrane of the
abdomen. They originate from nearly the same locality. The ring of the femoral
canal, 12, is situated immediately below, but to the inner side of the internal
inguinal ring, 3. The epigastric artery, 1, marks the width of the interval
which separates the two rings. Poupart’s ligament, 5, being the line of union
between the oblique aponeurosis of the abdominal muscle and the fascia lata,
merely overarches the femoral sheath, and does not separate it absolutely from
the spermatic sheath.

Plate 45.—Figure 2

PLATE 45, Fig. 3.—The peritonaeum, 2, 3, closes the femoral canal, 12, at the
femoral ring, in the same way as this membrane closes the inguinal canal at the
internal inguinal ring, 3, Fig. 2, Plate 45. The epigastric artery always holds
an intermediate position between both rings. The spermatic vessels in the
inguinal tube, 3, 3, Fig. 2, Plate 45, are represented by the round ligament in
the female inguinal canal, Fig. 3, Plate 45. When the bowel is about to
protrude at either of the rings, it first dilates the peritonaeum, which covers
these openings.

Plate 45.—Figure 3

PLATE 45, Fig. 4.—The place of election for the formation of any hernia is that
which is structurally the weakest. As the space which the femoral arch spans
external to the vessels is fully occupied by the psoas and iliacus muscles,
and, moreover, as the abdominal fibrous membrane and its prolongation, the
femoral sheath, closely embrace the vessels on their outer anterior and
posterior sides, whilst on their inner side the membrane and sheath are removed
at a considerable interval from the vessels, it is through this interval (the
canal) that the hernia may more readily pass. The peritonaeum, 2, and crural
septum, 13, form at this place the only barrier against the protrusion of the
bowel into the canal.

Plate 45.—Figure 4

PLATE 45, Fig. 5.—The hernia cannot freely enter the compartment, 10, occupied
by the artery, neither can it enter the place 11, occupied as it is by the
vein. It cannot readily pass through the inguinal wall at a point internal to,
9, the crural sheath, for here it is opposed by, 4, the conjoined tendon, and
by, 8, Gimbernat’s ligament. Neither will the hernia force a way at a point
external to the femoral vessels in preference to that of the crural canal,
which is already prepared to admit it. [Footnote] The bowel, therefore, enters
the femoral canal, 9, and herein it lies covered by its peritonaeal sac,
derived from that part of the membrane which once masked the crural ring. The
septum crurale itself, having been dilated before the sac, of course invests it
also. The femoral canal forms now the third covering of the bowel. If in this
stage of the hernia it should suffer constriction, Gimbernat’s ligament, 8, is
the cause of it. An incipient femoral hernia of the size of 2, 12, cannot, in
the undissected state of the parts, be detected by manual operation; for, being
bound down by the dense fibrous structures which gird the canal, it forms no
apparent tumour in the groin.

[Footnote: The mode in which the femoral sheath, continued from the abdominal
membrane, becomes simply applied to the sides of the vessels, renders it of
course not impossible for a hernia to protrude into the sheath at any point of
its abdominal entrance. Mr. Stanley and M. Cloquet have observed a femoral
hernia external to the vessels. Hesselbach has also met with this variety. A
hernia of this nature has come under my own observation. Cloquet has seen the
hernia descend the sheath once in front of the vessels, and once
behind them. These varieties, however, must be very rare. The external form has
never been met with by Hey, Cooper, or Scarpa; whilst no less than six
instances of it have come under the notice of Mr. Macilwain, (on Hernia, p.
293.)]

Plate 45.—Figure 5

PLATE 45, Fig. 6.—The hernia, 2, 12, increasing gradually in size, becomes
tightly impacted in the crural canal, and being unable to dilate this tube
uniformly to a size corresponding with its own volume, it at length bends
towards the saphenous opening, 6, 7, this being the more easy point of egress.
Still, the neck of the sac, 2, remains constricted at the ring, whilst the part
which occupies the canal is also very much narrowed. The fundus of the sac, 9*,
12, alone expands, as being free of the canal; and covering this part of the
hernia may be seen the fascia propria, 9*. This fascia is a production of the
inner wall of the canal; and if we trace its sides, we shall find its lower
part to be continuous with the femoral sheath, whilst its upper part is still
continuous with the fascia transversalis. When the hernia ruptures the
saphenous side of the canal, the fascia propria is, of course, absent.

Plate 45.—Figure 6

PLATE 46, Fig. 1.—The anatomical circumstances which serve for the diagnosis of
a femoral from an inguinal hernia may be best explained by viewing in contrast
the respective positions assumed by both complaints. The direct hernia, 13,
traverses the inguinal wall from behind, at a situation corresponding with the
external ring; and from this latter point it descends the scrotum. An oblique
external inguinal hernia enters the internal ring, 3, which exists further
apart from the general median line, and, in order to gain the external ring,
has to take an oblique course from without inwards through the inguinal canal.
A femoral hernia enters the crural ring, 2, immediately below, but on the inner
side of, the internal inguinal ring, and descends the femoral canal, 12,
vertically to where it emerges through, 6, 7, the saphenous opening. The direct
inguinal hernia, 13, owing to its form and position, can scarcely ever be
mistaken for a femoral hernia. But in consequence of the close relationship
between the internal inguinal ring, 3, and the femoral ring, 2, through which
their respective herniae pass, some difficulty in distinguishing between these
complaints may occur. An incipient femoral hernia, occupying the crural canal
between the points, 2, 12, presents no apparent tumour in the undissected state
of the parts; and a bubonocele, or incipient inguinal hernia, occupying the
inguinal canal, 3, 3, where it is braced down by the external oblique
aponeurosis, will thereby be also obscured in some degree. But, in most
instances, the bubonocele distends the inguinal canal somewhat; and the impulse
which on coughing is felt at a place above the femoral arch, will serve to
indicate, by negative evidence, that it is not a femoral hernia.

Plate 46.—Figure 1

PLATE 46, Fig. 2.—When the inguinal and femoral herniae are fully produced,
they best explain their distinctive nature. The inguinal hernia, 13, descends
the scrotum, whilst the femoral hernia, 9*, turns over the falciform process,
6, and rests upon the fascia lata and femoral arch. Though in this position the
fundus of a femoral hernia lies in the neighbourhood of the inguinal canal, 3,
yet the swelling can scarcely be mistaken for an inguinal rupture, since, in
addition to its being superficial to the aponeurosis which covers the inguinal
canal, and also to the femoral arch, it may be withdrawn readily from this
place, and its body, 12, traced to where it sinks into the saphenous opening,
6, 7, on the upper part of the thigh. An inguinal hernia manifests its proper
character more and more plainly as it advances from its point of origin to its
termination in the scrotum. A femoral hernia, on the contrary, masks its proper
nature, as well at its point of origin as at its termination. But when a
femoral hernia stands midway between these two, points—viz. in the saphenous
opening, 6, 7, it best exhibits its special character; for here it exists below
the femoral arch, and considerably apart from the external abdominal ring.

Plate 46.—Figure 2

PLATE 46, Fig. 3.—The neck of the sac of a femoral hernia, 2, lies always close
to, 3, the epigastric artery. When the obturator artery is derived from the
epigastric, if the former pass internal to the neck behind, 8, Gimbernat’s
ligament, it can scarcely escape being wounded when this structure is being
severed by the operator’s knife. If, on the other hand, the obturator artery
descend external to the neck of the sac, the vessel will be comparatively
remote from danger while the ligament is being divided. In addition to the fact
that the cause of stricture is always on the pubic side, 8, of the neck of the
sac, 12, thereby requiring the incision to correspond with this situation only,
other circumstances, such as the constant presence of the femoral vein, 11, and
the epigastric artery, 1, determine the avoidance of ever incising the canal on
its outer or upper side. And if the obturator artery, [Footnote] by rare
occurrence, happen to loop round the inner side of the neck of the sac,
supposing this to be the seat of stricture, what amount of anatomical
knowledge, at the call of the most dexterous operator, can render the vessel
safe from danger?

[Footnote: M. Velpeau (Medecine Operatoire), in reference to the relative
frequency of cases in which the obturator artery is derived from the
epigastric, remarks, “L’examen que j’ai pu en faire sur plusieurs milliers de
cadavres, ne me permet pas de dire qu’elle se rencontre un fois sur trois, ni
sur cinq, ni meme sur dix, mais bien seulement sur quinze a vingt.” Monro (Obs.
on Crural Hernia) states this condition of the obturator artery to be as 1 in
20-30. Mr. Quain (Anatomy of the Arteries) gives, as the result of his
observations, the proportion to be as 1 in 3-1/2, and in this estimate he
agrees to a great extent with the observations of Cloquet and Hesselbach.
Numerical tables have also been drawn up to show the relative frequency in
which the obturator descends on the outer and inner borders of the crural ring
and neck of the sac. Sir A. Cooper never met with an example where the vessel
passed on the inner side of the sac, and from this alone it may be inferred
that such a position of the vessel is very rare. It is generally admitted that
the obturator artery, when derived from the epigastric, passes down much more
frequently between the iliac vein and outer border of the ring. The researches
of anatomists (Monro and others) in reference to this point have given rise to
the question, “What determines the position of the obturator artery with
respect to the femoral ring?” It appears to me to be one of those questions
which do not admit of a precise answer by any mode of mathematical computation;
and even if it did, where then is the practical inference?]

The taxis, in a case of crural hernia, should be conducted in accordance with
anatomical principles. The fascia lata, Poupart’s ligament, and the abdominal
aponeurosis, are to be relaxed by bending the thigh inwards to the
hypogastrium. By this measure, the falciform process, 6, is also relaxed; but I
doubt whether the situation occupied by Gimbernat’s ligament allows this part
to be influenced by any position of the limb or abdomen. The hernia is then to
be drawn from its place above Poupart’s ligament, (if it have advanced so far,)
and when brought opposite the saphenous opening, gentle pressure made outwards,
upwards, and backwards, so as to slip it beneath the margin of the falciform
process, will best serve for its reduction. When this cannot be effected by the
taxis, and the stricture still remains, the cutting operation is required.

The precise seat of the stricture cannot be known except during the operation.
But it is to be presumed that the sac and contained intestine suffer
constriction throughout the whole length of the canal. [Footnote] Previously to
the commencement of the operation, the urinary bladder should be emptied; for
this organ, in its distended state, rises above the level of the pubic bone,
and may thus be endangered by the incision through the stricture—especially if
Gimbernat’s ligament be the structure which causes it.

[Footnote: “The seat of the stricture is not the same in all cases, though, in
by far the greater number of instances, the constriction is relieved by the
division upwards and inwards of the falciform process of the fascia lata, and
the lunated edge of Gimbernat’s ligament, where they join with each other. In
some instances, it will be the fibres of the deep crescentic (femoral) arch; in
others, again, the neck of the sac itself, and produced by a thickening and
contraction of the subserous and peritonaeal membranes where they lie within
the circumference of the crural ring.”—Morton (Surgical Anatomy of the
Groin p. 148).]

An incision commencing a little way above Poupart’s ligament, is to be carried
vertically over the hernia, parallel with, but to the inner side of its median
line. This incision divides the skin and subcutaneous adipose membrane, which
latter varies considerably in quantity in several individuals. One or two small
arteries (superficial pubic, &c.) may be divided, and some lymphatic bodies
exposed. On cautiously turning aside the incised adipose membrane contained
between the two layers of the superficial fascia, the fascia propria, 9, Figs.
4, 5, Plate 46, of the hernia is exposed. This envelope, besides varying in
thickness in two or more cases, may be absent altogether. The fascia closely
invests the sac, 12; but sometimes a layer of fatty substance interposes
between the two coverings, and resembles the omentum so much, that the operator
may be led to doubt whether or not the sac has been already opened. The fascia
is to be cautiously slit open on a director; and now the sac comes in view. The
hernia having been drawn outwards, so as to separate it from the inner wall of
the crural canal, a director [Footnote] is next to be passed along the interval
thus left, the groove of the instrument being turned to the pubic side. The
position of the director is now between the neck of the sac and the inner wall
of the canal. The extent to which the director passes up in the canal will vary
according to the suspected level of the stricture. A probe-pointed bistoury is
now to be slid along the director, and with its edge turned upwards and
inwards, according to the seat of stricture, the following mentioned parts are
to be divided—viz., the falciform process, 6; the inner wall of the canal,
which is continuous with the fascia propria, 9; Gimbernat’s ligament, 8; and
the conjoined tendon, 4; where this is inserted with the ligament into the
pectineal ridge. By this mode of incision, which seems to be all-sufficient for
the liberation of the stricture external to the neck of the sac, we avoid
Poupart’s ligament; and thereby the spermatic cord, 3, and epigastric artery,
1, are not endangered. The crural canal being thus laid open on its inner side,
and the constricting fibrous bands being severed, the sac may now be gently
manipulated, so as to restore it and its contents to the cavity of the abdomen;
but if any impediment to the reduction still remain, the cause, in all
probability, arises either from the neck of the sac having become strongly
adherent to the crural ring, or from the bowel being bound by bands of false
membrane to the sac. In either case, it will be necessary to open the sac, and
examine its contents. The neck of the sac is then to be exposed by an incision
carried through the integument across the upper end of the first incision, and
parallel with Poupart’s ligament. The neck is then to be divided on its inner
side, and the exposed intestine may now be restored to the abdomen.

[Footnote: The finger is the safest director; for at the same time that it
guides the knife it feels the stricture and protects the bowel. As all the
structures which are liable to become the seat of stricture—viz., the falciform
process, Gimbernat’s ligament, and the conjoined tendon, lie in very close
apposition, a very short incision made upwards and inwards is all that is
required.]

Plate 46—Figure 3

Plate 46—Figure 4

Plate 46—Figure 5

COMMENTARY ON PLATE 47.

THE SURGICAL DISSECTION OF THE PRINCIPAL BLOODVESSELS AND NERVES OF THE ILIAC
AND FEMORAL REGIONS.

Through the groin, as through the axilla, the principal blood vessels and
nerves are transmitted to, the corresponding limb. The main artery of the lower
limb frequently becomes the subject of a surgical operation. The vessel is
usually described as divisible into parts, according to the regions which it
traverses. But, as in examining any one of those parts irrespective of the
others, many facts of chief surgical importance are thereby obscured and
overlooked, I propose to consider the vessel as a whole, continuous from
the aorta to where it enters the popliteal space. The general course and
position of the main artery may be described as follows:—The abdominal aorta,
A, bifurcates on the body of the fourth lumbar vertebra. The level of the
aortic bifurcation corresponds with the situation of the navel in front, and
the crista ilii laterally. The aorta is in this situation borne so far forwards
by the lumbar spine as to occupy an almost central position in the cavity of
the abdomen. If the abdomen were pierced by two lines, one extending from a
little to the left side of the navel, horizontally backwards to the fourth
lumbar vertebra, and the other from immediately over the middle of one crista
ilii, transversely to a corresponding point in the opposite side, these lines
would intersect at the aortic bifurcation. The two arteries, G G,* into which
the aorta divides symmetrically at the median line, diverge from one another in
their descent towards the two groins. As both vessels correspond in form and
relative position, the description of one will serve for the other.

While the thigh is abducted and rotated outwards, if a line be drawn from the
navel to a point, D, of the inguinal fold, midway between B, the anterior iliac
spine, and C, the symphysis pubis, and continued thence to the inner condyle of
the femur, it would indicate the general course of the artery, G I W. In this
course, the vessel may be regarded as a main trunk, giving off at intervals
large branches for the supply of the pelvic organs, the abdominal parietes, and
the thigh. From the point where the vessel leaves the aorta, A, down to the
inguinal fold, D, it lies within the abdomen, and here, therefore, all
operations affecting the vessel are attended with more difficulty and danger
than elsewhere, in its course.

The artery of the lower limb, arising at the bifurcation of the aorta on the
fourth lumbar vertebra, descends obliquely outwards to the sacra-iliac
junction, and here it gives off its first branch, G, (internal iliac,) to the
pelvic organs. The main vessel is named common iliac, at the interval
between its origin from the aorta and the point where it gives off the internal
iliac branch. This interval is very variable as to its length, but it is stated
to be usually two inches. The artery, I, continuing to diverge in its first
direction from its fellow of the opposite side, descends along the margin of
the true pelvis as far as Poupart’s ligament, D, where it gives off its next
principal branches,—viz., the epigastric and circumflex iliac. At the interval
between the internal iliac and epigastric branches, the main artery, I, is
named external iliac; and the surgical length of this part is also
liable to vary, in consequence of the epigastric or circumflex iliac branches
arising higher up or lower down than usual. The main vessel, after passing
beneath the middle of Poupart’s ligament, D, next gives off the profundus
branch, N, to supply the thigh. This branch generally arises at a point an inch
and half or two inches below the fold of the groin; and between it and the
epigastric above, the main artery is named common femoral. From the
point where the profundus branch arises, down to the popliteal space, the
vessel remains as an undivided trunk, being destined to supply the leg and
foot. In this course, the artery is accompanied by the vein, H K O, which,
according to the region in which it lies, assumes different names,
corresponding to those applied to the artery. Both vessels may now be viewed in
relation to each other, and to the several structures which lie in connexion
with them.

The two vessels above Poupart’s ligament lie behind the intestines, and are
closely invested by the serous membrane. The origin of the vena cava, F, lies
close to the right side of the bifurcation of the aorta, A; and here both
vessels are supported by the lumbar spine. Each of the two arteries, G G,* into
which the aorta divides, has its accompanying vein, H, on its inner side, but
the common iliac part of the right artery is seen to lie upon the upper
portions of both the veins, as these joining beneath it form the commencement
of the vena cava. The external iliac part, I, of each artery has its vein, K,
on its inner side. At the point, G, where the artery gives off its internal
iliac branch, the ureter, g, crosses it, and thence descends to the
bladder. The internal iliac branch subdivides in general so soon after its
origin, that it may be regarded as for the most part an unsafe proceeding to
place a ligature upon it.

The iliac vessels, A G I, in approaching Poupart’s ligament along the border of
the true pelvis, are supported by the psoas muscle, and invested and bound to
their place by the peritonaeum, and a thin process of the iliac fascia. Some
lymphatic glands are here found to lie over the course of the vessels. The
spermatic artery and vein, together with the genito-crural nerve, descend along
the outer border of the iliac artery. When arrived at Poupart’s ligament, the
iliac vessels, I K, become complicated by their own branches, and also by the
spermatic vessels, as these are about to pass from the abdomen through the
internal inguinal ring. While passing beneath the middle of Poupart’s ligament,
D, the iliac artery, I, having its vein, K, close to its inner side, rests upon
the inner border of the psoas muscle, and in this place it may be effectually
compressed against the os pubis. The anterior crural nerve, P, which in the
iliac region lies concealed by the psoas muscle, and separated by this from the
vessels, now comes into view, lying on the outer side of the artery. When the
vessels have passed from beneath Poupart’s ligament, the serous membrane no
longer covers them, but the fibrous membrane is seen to invest them in the form
of a sheath, divided into two compartments, one of which (internal) receives
the vein, the other the artery. The iliac vessels, in passing to the thigh,
assume the name of femoral.

The femoral vessels, O N W, in the upper third of the thigh traverse a
triangular space, the base of which is formed by Poupart’s ligament, D, whilst
the sides and apex are formed by the sartorius, Q, and adductor longus muscles,
T, approaching each other. In the undissected state of the part, the structures
which bound this space can in general be easily recognised. A central
depression extends from the middle of its base, D, to its apex, V, and marks
the course of the vessels. Near the middle of Poupart’s ligament, the vessels
are comparatively superficial, and here the artery may be felt pulsating; but
lower down, as they approach the apex of the triangle, the vessels become
gradually deeper, till the sartorius muscle inclining from its origin obliquely
inwards to the centre of the thigh, w, at length overlaps them. The inner
border of the sartorius muscle at the lower part of the upper third of the
thigh, W, guides to the position of the artery. Whilst traversing the femoral
triangle, the vessels enclosed in their proper sheath are covered by the fascia
lata, adipose membrane, and integument. In this place they lie imbedded in
loose cellular and adipose tissue. The femoral vein, O, is on the same plane
with the artery near Poupart’s ligament; but from this place downwards through
the thigh, the vein gradually winds from the inner to the back part of the
artery; and when both vessels pass under cover of the sartorius, they enter a
strong fibrous sheath, V, derived from the tendons of the adductor muscles upon
which they lie. The artery approaches the shaft of the femur near its middle;
and in this place it may be readily compressed against the bone by the hand.
The anterior crural nerve, P, dividing on the outer side of the artery, sends
some of its branches coursing over the femoral sheath; and one of these—the
long saphenous nerve—enters the sheath and follows the artery as far as the
opening in the great adductor tendon. The femoral artery, before it passes
through this opening into the popliteal space, gives off its anastomatic
branch. The profundus branch, N, springs from the outer side of the femoral
artery usually at a distance of from one to two inches (seldom more) below
Poupart’s ligament, and soon subdivides. [Footnote] The femoral artery in a few
instances has been found double.

[Footnote: The ordinary length of each part of the main artery is stated on the
authority of Mr. Quain. See “Anatomy of the Arteries,” &c. ]

The main artery of the lower limb may be exposed and tied in any part of its
course from the aorta to the popliteal space. But the situation most eligible
for performing such an operation depends of course upon circumstances, both
anatomical and pathological. If an aneurism affect the popliteal part of the
vessel, or if, from whatever cause arising, it be found expedient to tie the
femoral above this part, the place best suited for the operation is that where
the artery, W, first passes under cover of the sartorius muscle. [Footnote]
For, considering that the vessel gives off no important branch destined to
supply any part of the thigh or leg between the profundus branch and those into
which it divides below the popliteal space, the arrest to circulation will be
the same in amount at whichever part of the vessel between these two points the
ligature be applied. But since the vessel in the situation specified can be
reached with greater facility here than elsewhere lower down; and since,
moreover, a ligature applied to it here will be sufficiently removed from the
profundus branch above, and the seat of disease below, to produce the desired
result, the choice of the operator is determined accordingly. The steps of the
operation performed at the situation W, where the artery is about to pass
beneath the sartorius, are these: an incision of sufficient length—from two to
three inches—is to be made over the course of the vessel, so as to divide the
skin and adipose membrane, and expose the fascia lata, through which the inner
edge of the sartorius muscle becomes now readily discernible. A vein (anterior
saphena) may be found to cross in this situation, but the saphena vein proper
is not met with, as this lies nearer the inner side of the thigh. The fascia
having been next divided, the edge of the sartorius is to be turned aside, and
now the pulsation of the artery in its sheath will indicate its exact position.
The sheath is next to be opened, for an extent sufficient only to carry the
point of the ligature-needle safely around the artery, care being taken not to
injure the femoral vein, which lies close behind it, and also to exclude any
nerve which may lie in contact with the vessel.

[Footnote: This is the situation chosen by Scarpa for arresting by ligature the
circulation through the femoral artery in cases of popliteal aneurism. The
reasons stated in the text are those which determine the surgeon to perform the
operation in this place in preference to that (the lower third of the thigh)
where Mr. Hunter first proposed to tie the vessel.]

If an aneurism affect the common femoral portion of the artery, the external
iliac part would require to be tied, because, between the seat of the tumour
and the epigastric and circumflex ilii branches above, there would not be
sufficient space to allow the ligature to rest undisturbed; and even if the
aneurism arose from the femoral below the profundus branch in the upper third
of the thigh, or if, after amputation of the thigh, a secondary haemorrhage
took place from the femoral and the profunda arteries, a ligature would with
more safety be applied to the external iliac part than to the common femoral;
because of this latter, even when of its clear normal length, presenting so
small an interval between the epigastric and profundus branches. In addition to
this, it must be noticed, that occasionally the profundus itself, or some one
of its branches, (external and internal circumflex, &c.), arises as high up
as Poupart’s ligament, close to the origin of the epigastric and circumflex
iliac. [Footnote]

[Footnote: The main artery (Plate 47) has been exposed in the iliac and femoral
regions with the object of showing the relation which its parts bear to each
other and to the whole; all the other dissections have been made upon the same
plan, the practical tendency of which will be illustrated when considering the
subject of arterial anastomosis.]

The external iliac part of the artery, G I, when requiring to be tied, may be
reached in the following way: an incision, commencing above the anterior iliac
spine, B, is to be carried inwards parallel to, and above, Poupart’s ligament,
D, as far as the outer margin of the internal abdominal ring. This incision is
the one best calculated for avoiding the epigastric artery, and for not
disturbing the peritonaeum more than is necessary. The skin and the three
abdominal muscles having been successively incised, the fibrous transversalis
fascia is next to be carefully divided, so as to expose the peritonaeum. This
membrane is then to be gently raised by the fingers, from off the iliacus and
psoas muscles as far inwards as the margin of the true pelvis where the artery
lies. On raising the peritonaeum the spermatic vessels will be found adhering
to it. The iliac artery itself is liable to be displaced by adhering to the
serous membrane, when this is being detached from the inner side of the psoas
muscle. [Footnote] The artery having been divested of its serous covering as
far up as a point midway between I G, the epigastric and internal iliac
branches, the ligature is to be passed around it in this place, as being
equidistant from these two sources of disturbance. As the vein, K, lies close
along the inner side of the artery, the point of the instrument should first be
inserted between them, and passed from within outwards, in order to avoid
wounding the vein. If an aneurism affect the upper end of the external iliac
artery, it is proposed to tie the common iliac; but this is an operation of so
serious a nature, that it can in this respect be exceeded only by tying the
aorta itself. The common iliac artery is so situated, that it can as easily be
reached from the groin upwards as from the side of the abdomen inwards, and in
both directions the peritonaeum would have to be disturbed to an equal extent.

[Footnote: The student, in operating upon the dead subject, is often puzzled to
find that the iliac artery does not appear in its usual situation, unaware at
the time that he has lifted the vessel in connexion with the peritonaeum. I
have once seen a very distinguished surgeon, whilst performing this operation
on the living body, at fault owing to the same cause.]

DESCRIPTION OF PLATE 47.

A. The aorta at its point of bifurcation.

B. The anterior superior iliac spine.

C. The symphysis pubis.

D. Poupart’s ligament, immediately above which are seen the circumflex ilii and
epigastric arteries, with the vas deferens and spermatic vessels.

E E*. The right and left iliac muscles covered by the peritonaeum; the external
cutaneous nerve is seen through the membrane.

F. The vena cava.

G G*. The common iliac arteries giving off the internal iliac branches on the
sacro-iliac symphyses; g g, the right and left ureters.

H H*. The right and left common iliac veins.

I I*. The right and left external iliac arteries, each is crossed by the
circumflex ilii vein.

K K *. The right and left external iliac veins.

L. The urinary bladder covered by the peritonaeum.

M. The rectum intestinum.

N. The profundus branch of the femoral artery.

O. The femoral vein; O, the saphena vein.

P. The anterior crural nerve.

Q. The sartorius muscle, cut.

S. The pectinaeus muscle.

T. The adductor longus muscle.

U. The gracilis muscle.

V. The tendinous sheath given off from the long adductor muscle, crossing the
vessels, and becoming adherent to the vastus internus muscle.

W. The femoral artery. The letter is on the part where the vessel becomes first
covered by the sartorius muscle.

Plate 47.

COMMENTARY ON PLATES 48 & 49.

THE RELATIVE ANATOMY OF THE MALE PELVIC ORGANS.

As the abdomen and pelvis form one general cavity, the organs contained in both
regions are thereby intimately related. The viscera of the abdomen completely
fill this region, and transmit to the pelvic organs all the impressions made
upon them by the diaphragm and abdominal walls. The expansion of the lungs, the
descent of the diaphragm, and the contraction of the abdominal muscles, cause
the abdominal viscera to descend and compress the pelvic organs; and at the
same time the muscles occupying the pelvic outlet, becoming relaxed or
contracted, allow the perinaeum to be protruded or sustained voluntarily
according to the requirements. Thus it is that the force originated in the
muscular parietes of the thorax and abdomen is, while opposed by the
counterforce of the perinæal muscles, brought so to bear upon the pelvic organs
as to become the principal means whereby the contents of these are evacuated.
The abdominal muscles are, during this act, the antagonists of the diaphragm,
while the muscles which guard the pelvic outlet become at the time the
antagonists of both. As the pelvic organs appear therefore to be little more
than passive recipients of their contents, the voluntary processes of
defecation and micturition may with more correctness be said to be performed
rather for them than by them. The relations which they bear to the abdomen and
its viscera, and their dependence upon these relations for the due performance
of the processes in which they serve, are sufficiently explained by
pathological facts. The same system of muscles comprising those of the thorax,
abdomen and perinaeum, performs consentaneously the acts of respiration,
vomiting, defecation and micturition. When the spinal cord suffers injury above
the origin of the phrenic nerve, immediate death supervenes, owing to a
cessation of the respiratory act. Considering, however, the effect of such an
injury upon the pelvic organs alone, these may be regarded as being absolutely
excluded from the pale of voluntary influence in consequence of the paralysis
of the diaphragm, the abdominal and perinæal muscles. The expulsory power over
the bladder and rectum being due to the opposing actions of these muscles above
and below, if the cord be injured in the neck below the origin of the phrenic
nerve, the inferior muscles becoming paralysed, the antagonism of muscular
forces is thereby interrupted, and the pelvic organs are, under such
circumstances, equally withdrawn from the sphere of volition. The antagonism of
the abdominal muscles to the diaphragm being necessary, in order that the
pelvic viscera may be acted upon, if the cord be injured in the lower dorsal
region, so as to paralyse the abdominal walls and the perinæal muscles, the
downward pressure of the diaphragm alone could not evacuate the pelvic organs
voluntarily, for the abdominal muscles are now incapable of deflecting the line
of force backwards and downwards through the pelvic axis; and the perinæal
muscles being also unable to act in agreement, the contents of the viscera pass
involuntarily. Again, as the muscular apparatus which occupies the pelvic
outlet acts antagonistic to the abdomen and thorax, when by an injury to the
cord in the sacral spine the perinæal apparatus alone becomes paralysed, its
relaxation allows the thoracic and abdominal force to evacuate the pelvic
organs involuntarily. It would appear, therefore, that the term “paralysis” of
the bladder or rectum, when following spinal injuries, &c. &c. means,
or should mean, only a paralytic state of the abdomino-pelvic muscular
apparatus, entirely or in part. For, in fact, neither the bladder nor rectum
ever acts voluntarily per se any more than the stomach does, and
therefore the name “detrusor” urinae, as applied to the muscular coat investing
the bladder, is as much a misnomer (if it be meant that the act of voiding the
organ at will be dependent upon it) as would be the name “detrusor” applied to
the muscular coat of the stomach, under the meaning that this were the agent in
the spasmodic effort of vomiting.

The urinary bladder, G, Plate 49, (in the adult body,) occupies the true pelvic
region when the organ is collapsed, or only partly distended. It is situated
behind the pubic symphysis and in front of the rectum, C,—the latter lies
between it and the sacrum, A. In early infancy, when the pelvis is
comparatively small, the bladder is situated in the hypogastric region, with
its summit pointing towards the umbilicus; as the bladder varies in shape,
according to whether it be empty or full, its relations to neighbouring parts,
especially to those in connexion with its summit, vary also considerably. When
empty, the back and upper surface of the bladder collapse against its forepart,
and in this state the organ lies flattened against the pubic symphysis. Whether
the bladder be distended or not, the small intestines lie in contact with its
upper surface, and compress it in the manner of a soft elastic cushion. When
distended largely, its summit is raised above the pubic symphysis, the small
intestines having yielded place to it, and in this state it can be felt by the
hand laid upon the hypogastrium.

The shape of the bladder varies in different individuals. In some it is
rounded, in others pyriform, in others peaked towards its summit. Its capacity
varies also considerably at different ages and in different sexes. When
distended, its long axis will be found to coincide with a line passing from a
point midway between the navel and pubes to the point of the coccyx, the
obliquity of this direction being greatest when the body is in the erect
posture, for the intestines now gravitate upon it. When the body is recumbent,
the bladder recedes somewhat from the pubes, and as the intestines do not now
press upon it from above, it allows of being distended to a much greater degree
without causing uneasiness, and a desire to void its contents.

The manner in which the bladder is connected to neighbouring parts is such as
to admit of its full distension. Its summit, back, and upper sides are free and
covered by the elastic peritonaeum, whilst its front, lower sides, and base are
adherent to adjacent parts, and divested of the serous membrane. On tracing the
peritonaeum from the front wall of the abdomen to its point of reflexion over
the summit of the bladder, we find the membrane to be in this part so loosely
adherent, that the bladder when much distended, raises the peritonaeum above
the level of the upper margin of the pubic symphysis. In this state the organ
may be punctured immediately above the pubic symphysis without endangering the
serous sac. When the bladder is collapsed, the peritonaeum follows its summit
below the level of the pubes, and in this position of the organ such an
operation would be inadmissible, if indeed the necessity for it can now be
conceived.

By removing the os innominatum, A D, Plate 48, together with the internal
obturator, and levator ani muscles, which arise from its inner side, we obtain
a lateral view, Plate 49, of the pelvic viscera, and of the vessels &c.
connected with them. Those parts of the bladder, G, and the rectum, C, which
are invested by the peritonaeum, are also now fully displayed. On tracing this
membrane from before backwards, over the summit of the bladder, G, we find it
descending deeply upon the posterior surface of the organ, before it becomes
reflected so as to ascend over the forepart of the rectum. This duplicature of
the serous membrane, H H, is named the recto-vesical pouch, and it is required
to ascertain with all the exactness possible the level to which it descends, so
as to avoid it in the operation of puncturing the bladder through the rectum.
The serous pouch descends lower in some bodies than in others; but in all there
exists a space, of greater or less dimensions, between it and the prostate, V,
whereat the base of the bladder is in direct apposition with the rectum, W, the
serous membrane not intervening.

When the peritonaeum is traced from one iliac fossa to the other, we find it
sinking deeply into the hollow of the pelvis behind the bladder, so as to form
the sides of the recto-vesical pouch; but when traced over the summit of the
bladder, this organ is seen to have the membrane reflected upon it, almost
immediately below the pelvic brim. At the situations where the peritonaeum
becomes reflected in front, laterally, and behind, upon the sides of the
bladder, the membrane is thrown into folds, which are named “false ligaments.”
The pelvic fascia, in being reflected to the bladder from the front and sides
of the pelvis, at a lower level than that of the peritonaeum, forms the “true
ligaments.” In addition to these ligaments, which serve to keep the base and
front of the bladder fixed in the pelvis, other structures, such as the
ureters, K, the vasa deferentia, I, the hypogastric cords, the urachus, and the
bloodvessels, embrace the organ in various directions, and act as bridles, to
limit its expansion more or less in all directions, but least so towards its
summit, which is always comparatively free.

The neck and outlet of the bladder, V, are situated at the anterior part of its
base, and point towards the subpubic space. The prostate gland, V, surrounds
its neck, and occupies a position behind and below the pubic arch, D, and in
front of the rectum, W. The gland, V, being of a rounded form and dense
structure, can be felt in this situation by the finger, passed upwards through
the bowel. The prostate is suspended from the back of the pubic arch by the
anterior true ligament of the bladder, and at its forepart, where the
membranous portion of the urethra commences, this passes through the deep
perinæal fascia, X. The anterior fibres of the levator ani muscle embrace the
prostate on both its sides. Behind the base of the prostate, the ureter, K, is
seen to enter the coats of the bladder obliquely, whilst the vas deferens, I,
joined by the vesicula seminalis, L, penetrates the substance of the prostate,
V, at its lower and back part, which lies in apposition with the rectum.

The rectum, W C, at its middle and upper parts, occupies the hollow of the
sacrum, A Q, and is behind the bladder. The lower third of the rectum, W, not
being covered by the peritonaeum, is that part on which the various surgical
operations are performed. At its upper three-fifths, the rectum describes a
curve corresponding to that of the sacrum; and if the bladder be full, its
convex back part presses the bowel against the bone, causing its curve to be
greater than if the bladder were empty and collapsed. This fact requires to be
borne in mind, for, in order to introduce a bougie, or to allow a large
injection to pass with freedom into the bowel, the bladder should be first
evacuated. The coccygeal bones, Q, continuing in the curve of the sacrum, bear
the rectum, W, forwards against the base of the bladder, and give to this part
a degree of obliquity upwards and backwards, in respect to the perinaeum and
anus. From the point where the prostate, V, lies in contact with the rectum, W,
this latter curves downwards, and slightly backwards, to the anus, P. The
prostate is situated at a distance of about an inch and a half or two inches
from the anus—the distance varying according to whether the bladder and bowel
be distended or not. [Footnote]

[Footnote: The distance between any two given parts is found to vary in
different cases. “In subjects of an advanced age,” Mr. Stanley remarks, “a deep
perinaeum, as it is termed, is frequently met with. This may be occasioned
either by an unusual quantity of fat in the perinaeum, or by an enlarged
prostate, or by the dilatation of that part of the rectum which is contiguous
to the prostate and bladder. Under either of these circumstances, the prostate
and bladder become situated higher in the pelvis than naturally, and
consequently at a greater distance from the perinaeum.”—On the Lateral
Operation of Lithotomy.]

The arteries of the bladder are derived from the branches of the internal
iliac, S. The rectum receives its arteries from the inferior mesenteric and
pudic. The veins which course upwards from the rectum are large and numerous,
and devoid of valves. When these veins become varicose, owing to a stagnation
of their circulation, produced from whatever cause, the bowel is liable to be
affected with haemorrhoids or to assume a haemorrhagic tendency.

The pudic artery, S s, is a branch of the internal iliac. It passes from
the pelvis by the great sciatic foramen, below the pyriformis muscle, and in
company with the sciatic artery. The pudic artery and vein wind around the
spine, E, of the ischium, where they are joined by the pudic nerve, derived
from, T, the sacral plexus. The artery, in company with the nerve and vein,
re-enters the pelvis by the small sciatic foramen, and gets under cover of a
dense fibrous membrane (obturator fascia), between which and the obturator
muscle, it courses obliquely downwards and forwards to the forepart of the
perinaeum. At the place where the vessel re-enters the pelvis, it lies removed
at an interval of an inch and a half from the perinaeum, but becomes more
superficial as it approaches the subpubic space, N. The levator ani muscle
separates the pudic vessels and nerves from the sides of the rectum and
bladder. The principal branches given off from the pudic artery of either side,
are (1st), the inferior hemorrhoidal, to supply the lower end of the rectum;
(2nd), the transverse and superficial perinæal; (3rd), the artery of the bulb;
(4th), that which enters the corpus cavernosum of the penis, N; and (5th), the
dorsal artery of the penis. [Footnote] The branches given off from the pudic
nerve correspond in number and place to those of the artery. Having now
considered the relations of the pelvic organs in a lateral view, we are better
prepared to understand these relations when seen at their perinæal aspect.

[Footnote: The pudic artery, or some one of its branches, occasionally
undergoes marked deviations from the ordinary course. In Mr. Quain’s work,
(“Anatomy of the Arteries,”) a case is represented in which the artery of the
bulb arose from the pudic as far back as the tuber ischii, and crossed the line
of incision made in the lateral operation of lithotomy. In another figure is
seen a vessel (“accessory pudic”), which, passing between the base of the
bladder and the levator ani muscle, crosses in contact with the left lobe of
the prostate.]

DESCRIPTION OF PLATES 48 & 49.

PLATE 48.

A. The anterior superior iliac spine.

B. The anterior inferior iliac spine.

C. The acetabulum; c, the ligamentum teres.

D. The tuber ischii.

E. The spine of the ischium.

F. The pubic horizontal ramus.

G. The summit of the bladder covered by the peritonaeum.

H. The femoral artery.

I. The femoral vein.

K. The anterior crural nerve.

L. The thyroid ligament.

M. The spermatic cord.

N. The corpus cavernosum penis; n, its artery.

O. The urethra; o, the bulbus urethrae.

P. The sphincter ani muscle.

Q. The coccyx.

R. The sacro-sciatic ligament.

S. The pudic artery and nerve.

T. The sacral nerves.

U. The pyriformis muscle, cut.

V. The gluteal artery.

W. The small gluteus muscle.

Plate 48

PLATE 49.

A. The part of the sacrum which joins the ilium.

B. The external iliac artery, cut across.

C. The upper part of the rectum.

D. The ascending pubic ramus.

E. The spine of the ischium, cut.

F. The horizontal pubic ramus, cut.

G. The summit of the bladder covered by the peritonaeum; G *, its side, not
covered by the membrane.

H H. The recto-vesical peritonaeal pouch,

I. The vas deferens.

K. The ureter.

L. The vesicula seminalis.

M, N, O, P, Q, R, S, T, U, refer to the same parts as in Plate 48.

V. The prostate.

W. The lower part of the rectum.

X. The deep perinæal fascia.

Plate 49

COMMENTARY ON PLATES 50 & 51.

THE SURGICAL DISSECTION OF THE SUPERFICIAL STRUCTURES OF THE MALE PERINAEUM.

The median line of the body is marked as the situation where the opposite
halves unite and constitute a perfect symmetrical figure. Every
structure—superficial as well as deep—which occupies the median line is either
single, by the union of halves, or dual, by the cleavage and partition of
halves. The two sides of the body being absolutely similar, the median line at
which they unite is therefore common to both. Union along the median line is an
occlusion taking place by the junction of sides; and every hiatus or opening,
whether normal or abnormal, which happens at this line, signifies an omission
in the process of central union. The sexual peculiarities are the results of
the operation of this law, and all forms which are anomalous to either sex, may
be interpreted as gradations in the same process of development; a few of these
latter occasionally come under the notice of the surgeon.

The region which extends from the umbilicus to the point of the coccyx is
marked upon the cutaneous surface by a central raphe dividing the hypogastrium,
the penis, the scrotum, and the perinaeum respectively into equal and similar
sides. The umbilicus is a cicatrix formed after the metamorphosis of a median
foetal structure—the placental cord, &c. In the normal form, the meatus
urinarius and the anus coincide with the line of the median raphe, and signify
omissions at stated intervals along the line of central union. When between
these intervals the process of union happens likewise to be arrested,
malformations are the result; and of these the following are
examples:—Extrusion of the bladder at the hypogastrium is caused by a
congenital hiatus at the lower part of the linea alba, which is in the median
line; Epispadias, which is an urethral opening on the dorsum of the penis; and
Hypospadias, which is a similar opening on its under surface, are of the same
nature—namely, omissions in median union. Hermaphrodism may be interpreted
simply as a structural defect, compared to the normal form of the male, and as
a structural excess compared to that of the female. Spina bifida is a
congenital malformation or hiatus in union along the median line of the sacrum
or loins. As the process of union along the median line may err by a defect or
omission, so may it, on the other hand, err by an excess of fulfilment, as, for
example, when the urethra, the vagina, or the anus are found to be imperforate.
As the median line of union thus seems to influence the form of the
hypogastrium, the genitals, and the perinaeum, the dissection of these parts
has been conducted accordingly.

By removing the skin and subjacent adipose membrane from the hypogastrium, we
expose the superficial fascia. This membrane, E E E*, Fig. 1, Plate 50, is, in
the middle line, adherent to B, the linea alba, and thereby contributes to form
the central depression which extends from the navel to the pubes. The adipose
tissue, which in some subjects accumulates on either side of the linea alba,
renders this depression more marked in them. At the folds of the groin the
fascia is found adherent to Poupart’s ligament, and this also accounts for the
depressions in both these localities. From the central linea alba to which the
fascia adheres, outwards on either side to the folds of both groins, the
membrane forms two distinct sacs, which droop down in front, so as to invest
the testicles, E**, and penis in a manner similar to that of the skin covering
these parts. As the two sacs of the superficial fascia join each other at the
line B, coinciding with the linea alba, they form by that union the suspensory
ligament of the penis, which is a structure precisely median.

The superficial fascia having invested the testicles each in a distinct sac,
the adjacent sides of both these sacs, by joining together, form the median
septum scroti, E, Fig. 2, Plate 50. In the perinaeum, Fig. 1, Plate 51, the
fascia, A, may be traced from the back of the scrotum to the anus. In this
region the membrane is found to adhere laterally to the rami of the ischium and
pubes; whilst along the median perinæal line the two sacs of which the membrane
is composed unite, as in the scrotum, and form an imperfect septum. In front of
the anus, beneath the sphincter ani, the fascia degenerates into cellular
membrane, one layer of which is spread over the adipose tissue in the
ischio-rectal space, whilst its deeper and stronger layer unites with the deep
perinæal fascia, and by this connexion separates the urethral from the anal
spaces. The superficial fascia of the hypogastrium, the scrotum, and the
perinaeum forming a continuous membrane, and being adherent to the several
parts above noticed, may be regarded as a general double sac, which isolates
the inguino-perinæal region from the femoral and anal regions, and hence it
happens that when the urethra becomes ruptured, the urine which is extravasated
in the perinaeum, is allowed to pass over the scrotum and the abdomen,
involving these parts in consequent inflammation, whilst the thighs and anal
space are exempt. The tunicae vaginales, which form the immediate coverings of
the testicles, cannot be entered by the urine, as they are distinct sacs
originally protruded from the abdomen. It is in consequence of the imperfect
state of the inguino-perinæal septum of the fascia, that urine effused into one
of the sacs is allowed to enter the other.

Like all the other structures which join on either side of the median line, the
penis appears as a symmetrical organ, D D, Fig. 2, Plate 50. While viewed in
section, its two corpora cavernosa are seen to unite anteriorly, and by this
union to form a septum “pectiniforme;” posteriorly they remain distinct and
lateral, F F, Fig. 2, Plate 51, being attached to the ischio-pubic rami as the
crura penis. The urethra, B, Fig. 2, Plate 50, is also composed of two sides,
united along the median line, but forming between them a canal by the cleavage
and partition of the urethral septum. All the other structures of the perinaeum
will be seen to be either double and lateral, or single and median, according
as they stand apart from, or approach, or occupy the central line.

The perinaeum, Figs. 1, 2, Plate 51, is that space which is bounded above by
the arch of the pubes, behind by C, the os coccygis, and the lower borders of,
I I, the glutaei muscles and sacro-sciatic ligaments, and laterally by D D, the
ischiatic tuberosities. The osseous boundaries can be felt through the
integuments. Between the back of the scrotum and the anus the perinaeum swells
on both sides of the raphe, A B, Fig. 3, Plate 50, and assumes a form
corresponding with the bag of the superficial fascia which encloses the
structures connected with the urethra. The anus is centrally situated in the
depression formed between D D, the ischiatic tuberosities, and the double folds
of the nates.

The perinaeum, Fig. 3, Plate 50, is, for surgical purposes, described as
divisible into two spaces (anterior and posterior) by a transverse line drawn
from one tuber ischii, D, to the other, D, and crossing in front of the anus.
The anterior space, A D D, contains the urethra; the posterior space, D D C,
contains the rectum. The central raphe, A B C, traverses both these spaces. The
anterior or urethral space is (while viewed in reference to its osseous
boundaries) triangular in shape, the apex being formed by the pubic symphysis
beneath A, whilst two lines drawn from A to D D, would coincide with the
ischio-pubic rami which form its sides. The raphe in the anterior space
indicates the central position of the urethra, as may be ascertained by passing
a sound into the bladder, when the shaft of the instrument will be felt
prominently between the points A B. Behind the point B, the sound or staff
sinks deeper in the perinaeum as it follows the curve of the urethra towards
the bladder, and becomes overlaid by the bulb, &c.

The ischiatic tuberosities, D D, Fig. 3, Plate 50, are, in all subjects,
sufficiently prominent to be felt through the integuments, &c.; and the
line which, when drawn from one to the other, serves to divide the two perinæal
spaces, forms the base of the anterior one. In well-formed subjects, the
anterior space is equiangular, the base being equal to each side; but according
as the tuberosities approach the median line, the base becomes narrowed, and
the triangle is thereby rendered acute. These circumstances influence the
direction in which the first incision in the lateral operation of lithotomy
should be made. When the tuberosity of the left ischium stands well apart from
the perinæal centre, the line of incision, B E, Fig. 3, Plate 50, is carried
obliquely from above downwards and outwards; but in cases where the tuberosity
approaches the centre, the incision must necessarily be made more vertical. The
posterior perinæal space may be described on the surface by two lines drawn
from D D, the ischiatic tuberosities, to C, the point of the coccyx, whilst the
transverse line between D and D bounds it above.

By removing the integument and superficial fascia, we expose the superficial
vessels and nerves, together with the muscles in the neighbourhood of the
urethra and the anus. The accelerator urinae, E, Fig. 2, Plate 51, which
embraces the urethra, and the sphincter ani, B C, which surrounds the anus, H,
occupy the median line, and are divided each into halves by a central tendon, E
B C, which traverses the perinaeum from before backwards, to the point of the
coccyx. On either side of the anus, in the ischio-rectal space, D D, Fig. 1,
Plate 51, is found a considerable quantity of granular adipose tissue,
traversed by the inferior haemorrhoidal arteries and nerves-branches of the
pudic artery and nerve.

In front of the anus are seen two small muscles (transversae perinaei), G G,
Fig. 2, Plate 51, each arising from the tuber ischii of its own side, and the
two becoming inserted into, B, the central tendon. These transverse muscles
serve to mark the boundary between the anterior and posterior perinæal spaces.
Behind each muscle is found a small artery, crossing to the median line. The
left transverse muscle and artery are always divided in the lateral operation
of lithotomy. On the outer sides of the anterior perinæal space are seen the
erectores penis muscles, F F, overlaying the crura penis. Between each muscle
and the accelerator urinae, the superficialis perinaei artery and nerve course
forwards to the scrotum, &c.

The perinæal muscles having been brought fully into view, Plate 52, Fig. 1,
their symmetrical arrangement on both sides of the median line at once strikes
the attention. On either side of the anterior space appears a small angular
interval, L, formed between B, the accelerator urinae, D, the erector penis,
and E, the transverse muscle. Along the surface of this interval, the
superficial perinæal artery and nerve are seen to pass forwards; and deep in
it, beneath these, may also be observed, L, the artery of the bulb, arising
from the pudic, and crossing inwards, under cover of the anterior layer of the
membrane named the deep perinæal fascia. The first incision in the lateral
operation of lithotomy is commenced over the inferior inner angle of this
interval.

The muscles occupying the anterior perinæal space require to be removed, Fig.
1, Plate 53, in order to expose the urethra, B M, the crus penis, D, and the
deep perinæal fascia. The fascia will be now seen stretched across the subpubic
triangular space, reaching from one ischio-pubic ramus to the other, whilst by
its lower border, corresponding with the line of the transversae perinaei
muscles, it becomes continuous with the superficial fascia, in the manner
before described. The deep perinæal fascia (triangular ligament) encloses
between its two layers, C E, on either side of the urethra, the pudic artery,
the artery of the bulb, Cowper’s glands, and some muscular fibres occasionally
to be met with, to which the name “Compressor urethrae” has been assigned. At
this stage of the dissection, as the principal vessels and parts composed of
erectile tissue are now in view, their relative situations should be well
noticed, so as to avoid wounding them in the several cutting operations
required to be performed in their vicinity.

Along the median line (marked by the raphe) from the scrotum to the coccyx, and
close to this line on either side, the vessels are unimportant as to size. The
urethra lies along the middle line in the anterior perinæal space; the rectum
occupies the middle in the posterior space. When either of these parts
specially requires to be incised—the urethra for impassable stricture, &c.,
and the lower part of the rectum for fistula in ano—the operation may be
performed without fear of inducing dangerous arterial haemorrhage. With the
object of preserving from injury these important parts, deep incisions at, or
approaching to, the middle line must be avoided. The outer (ischio-pubic)
boundary of the perinaeum is the line along which the pudic artery passes. The
anterior half of this boundary supports also the crus penis; hence, therefore,
in order to avoid these, all deep incisions should be made parallel to, but
removed to a proper distance from this situation. The structures placed at the
middle line, B M F, Fig. 2, Plate 52, and those in connexion with the left
perinæal boundary, D G L, require (in order to insure the safety of these
parts) that the line of incision necessary to gain access to the neck of the
bladder in lithotomy should be made through the left side of the perinaeum from
a point midway between M, the bulb, and D, crus penis above, to a point, K,
midway between the anus, F, and tuber ischii, G, below. As the upper end of
this incision is commenced over the situation of the superficial perinæal
artery and the artery of the bulb, the knife at this place should only divide
the skin and superficial fascia. The lower end, K, just clears the outer side
of the dilated lower part of the rectum. The middle of the incision is over the
left lobe of the prostate gland and neck of the bladder, which parts, together
with the membranous portion of the urethra, are still concealed by the deep
perinæal fascia, the structures between its layers, and the anterior fibres of
K, the levator ani muscle. The incision, if made in due reference to the
relative situation of the parts above noticed, will leave them untouched; but
when the pudic artery, or some one of its branches, deviates from its ordinary
course and crosses the line of incision, a serious haemorrhage will ensue,
despite the anatomical knowledge of the most experienced operator. When it is
requisite to divide the superficial and deep sphincter ani as in the operation
for complete fistula in ano, if the incision be made transversely in the
ischio-rectal fossa, the haemorrhoidal arteries and nerves converging towards
the anus will be the more likely to escape being wounded.

DESCRIPTION OF THE FIGURES OF PLATES 50 & 51.

PLATE 50.

FIGURE 1.

A. The umbilicus.

B. The linea alba.

C. The suspensory ligament of the penis.

D D. The two corpora cavernosa penis.

E E**. The hypogastric and scrotal superficial fascia.

F F. The spermatic cords.

FIGURE 2.

A. The umbilicus.

B. The urethra.

C*. The tunica vaginalis; c, the testicle invested by the tunic.

D D. The corpora cavernosa seen in section.

E. The scrotal raphe and septum scroti.

FIGURE 3.

A B. The perinæal raphè.

C. The place of the coccyx.

D D. The projections of the ischiatic tuberosities.

BE. The line of section in lithotomy.

Plate 50

PLATE 51.

FIGURE 1.

A. The superficial fascia covering the urethral space.

B. The sphincter ani.

C. The coccyx.

D D. The right and left ischiatic tuberosities.

H. The anus.

I I. The glutei muscles.

FIGURE 2.

A, B, C, D, H, I. The same parts as in Fig. 1.

E. The accelerator urinae muscle.

F F. Right and left erector penis muscle.

G G. Right and left transverse muscle.

Plate 51

COMMENTARY ON PLATES 52 & 53.

THE SURGICAL DISSECTION OF THE DEEP STRUCTURES OF THE MALE PERINAEUM.

THE LATERAL OPERATION OF LITHOTOMY.

The urethra, at its membranous part, M, Fig. 1, Plate 53, which commences
behind the bulb, perforates the centre of the deep perinaeal fascia, E E, at
about an inch and a half in front of F, the anus. The anterior layer of the
fascia is continued forwards over the bulb, whilst the posterior layer is
reflected backwards over the prostate gland.

Behind the deep perinaeal fascia, the anterior fibres of K, the levator ani
muscle, arise from either side of the pubic symphysis posteriorly, and descend
obliquely down wards and forwards, to be inserted into the sides of N N, the
rectum above the anus. These fibres of the muscle, and the lower border of the
fascia which covers them, lie immediately in front of the prostate, C C, Fig.
2, Plate 53, and must necessarily be divided in the operation of lithotomy.
Previously to disturbing the lower end of the rectum from its natural position
in the perinaeum, its close relation to the prostate and base of the bladder
should be noticed. While the anus remains connected with the deep perinaeal
fascia in front, the fibres of the levator ani muscle of the left side may be
divided; and by now inserting the finger between them and the rectum, the left
lobe of the prostate can be felt in apposition with the forepart of the bowel,
an inch or two above the anus. It is owing to this connexion between these
parts that the lithotomist has to depress the bowel, lest it be wounded, while
the prostate is being incised. If either the bowel or the bladder, or both
together, be over-distended, they are brought into closer apposition, and the
rectum is consequently more exposed to danger during the latter stages of the
operation. The prostate being in contact with the rectum, the surgeon is
enabled to examine by the touch, per anum, the state of the gland. If
the prostate be diseased and irregularly enlarged, the urethra, which passes
through it, becomes, in general, so distorted, that the surgeon, after passing
the catheter along the urethra as far as the prostate, will find it necessary
to guide the point of the instrument into the bladder, by the finger introduced
into the bowel. The middle or third lobe of the prostate being enlarged, bends
the prostatic part of the urethra upwards. But when either of the lateral lobes
is enlarged, the urethra becomes bent towards the opposite side.

By dividing the levator ani muscle on both sides of the rectum, F, Fig. 2,
Plate 53, and detaching and depressing this from the perinaeal centre, the
prostate, C C, and base of the bladder, P, are brought into view. The pelvic
fascia may be now felt reflected from the inner surface of the levator ani
muscle to the bladder at a level corresponding with the base of the prostate,
and the neck of the bladder in front, and the vesiculae seminales, N N,
laterally. In this manner the pelvic fascia serves to insulate the perinaeal
space from the pelvic cavity. The prostate occupies the centre of the
perinaeum. If the perinaeum were to be penetrated at a point midway between the
bulb of the urethra and the anus, and to the depth of two inches straight
backwards, the instrument would transfix the apex of the gland. Its left lobe
lies directly under the middle of the line of incision which the lithotomist
makes through the surface; a fibrous membrane forms a capsule for the gland,
and renders its surface tough and unyielding, but its proper substance is
friable, and may be lacerated or dilated with ease, after having partly incised
its fibrous envelope. The membranous part of the urethra, M, Fig. 2, Plate 53,
enters the apex of the prostate, and traverses this part in a line, nearer to
the upper than to the under surface; and that portion of the canal which the
gland surrounds, is named prostatic. The prostate is separated from the pudic
artery by the levator ani muscle, and from the artery of the bulb, by the deep
perinaeal fascia and the muscular fibres enclosed between its two layers.

The prostate being a median structure, is formed of two lobes, united at the
median line. The bulbus urethrae being also a median structure, is occasionally
found notched in the centre, and presenting a bifid appearance. On the base of
the bladder, P, Fig. 2, Plate 53, the two vasa deferentia, Q Q, are seen to
converge from behind forwards, and enter the base of the gland; a triangular
interval is thus formed between the vasa, narrower before than behind, and at
the middle of this place the point of the trocar is to be passed (through the
rectum,) for the purpose of evacuating the contents of the bladder, when other
measures fail. When this operation is required to be performed, the situation
of the prostate is first to be ascertained through the bowel; and at a distance
of an inch behind the posterior border of the gland, precisely in the median
line, the distended base of the bladder may be safely punctured. If the trocar
pierce the bladder at this point, the seminal vessels converging to the
prostate from either side, and the recto-vesical serous pouch behind, will
escape being wounded. If the prostate happen to be much enlarged, the relative
position of the neighbouring parts will be found disturbed, and in such case
the bladder can be punctured above the pubes with greater ease and safety. In
cases of impassable stricture, when extravasation of urine is
threatened, or has already occurred, the urethra should be opened in the
perinaeum behind the place where the stricture is situated, and this (in the
present instance) certainly seems to be the more effectual measure, for at the
same time that the stricture is divided, the contents of the bladder may be
evacuated through the perinaeum. If the membranous part of the urethra be that
where the stricture exists, a staff with a central groove is to be passed as
far as the strictured part, and having ascertained the position of the
instrument by the finger in the bowel, the perinaeum should be incised, at the
middle line, between the bulb of the urethra and the anus. The urethra in this
situation will be found to curve backwards at the depth of an inch or more from
the surface. The point of the staff is now to be felt for, and the urethra is
to be incised upon it. The bistoury is next to be carried backwards through the
stricture till it enters that part of the urethra (usually dilated in such
cases) which intervenes between the seat of obstruction and the neck of the
bladder.

The lateral operation of lithotomy is to be performed according to the above
described anatomical relations of the parts concerned. The bowel being empty
and the bladder moderately full, a staff with a groove in its left side is to
be passed by the urethra into the bladder. The position and size of the
prostate is next to be ascertained by the left fore-finger in the rectum.
Having now explored the surface of the perinaeum in order to determine the
situation of the left tuberosity and ischio-pubic ramus, in relation to the
perinaeal middle line, the staff being held steadily against the symphysis
pubis, the operator proceeds to divide the skin and superficial fascia on the
left side of the perinaeum, commencing the incision on the left of the raphe
about an inch in front of the anus, and carrying it downwards and outwards
midway between the anus and ischiatic tuberosity, to a point below these parts.
The left fore-finger is then to be passed along the incision for the purpose of
parting the loose cellular tissue; and any of the more resisting structures,
such as the transverse and levator ani muscles, are to be divided by the knife.
Deep in the forepart of the wound, the position of the staff is now to be felt
for, and the structures which cover the membranous portion of the urethra are
to be cautiously divided. Recollecting now that the artery of the bulb passes
anterior to the staff in the urethra on a level with the bulb, the vessel is to
be avoided by inserting the point of the knife in the groove of the staff as
far backwards—that is, as near the apex of the prostate—as possible. The point
of the knife having been inserted in the groove of the staff, the bowel is then
to be depressed by the left fore-finger; and now the knife, with its back to
the staff, and its edge lateralized (towards the lower part of the left tuber
ischii), is to be pushed steadily along the groove in the direction of the
staff, and made to divide the membranous part of the urethra and the anterior
two-thirds of the left lobe of the prostate. The gland must necessarily be
divided to this extent if the part of the urethra which it surrounds be
traversed by the knife. The extent to which the prostate is divided depends
upon the degree of the angle which the knife, passing along the urethra, makes
with the staff. The greater this angle is, the greater the extent to which the
gland will be incised. The knife being next withdrawn, the left fore-finger is
to be passed through the opening into the bladder, and the parts are to be
dilated by the finger as it proceeds, guided by the staff. The staff is now to
be removed while the point of the finger is in the neck of the bladder, and the
forceps is to be passed into the bladder along the finger as a guide. The
calculus, now in the grip of the forceps, is to be extracted by a slow
undulating motion.

The general rules to be remembered and adopted in performing the operation of
lithotomy are as follow:—1st, The incision through the skin and sub-cutaneous
cellular membrane should be freely made, in order that the stone may be easily
extracted and the urine have ready egress. The incision which (judging from the
anatomical relations of the parts) appears to be best calculated to effect
these objects, is one which would extend from a point an inch above the anus to
a point in the posterior perinaeal space an inch or more below the anus. The
wound thus made would depend in relation to the neck of the bladder; the
important parts, vessels, &c., in the anterior perinaeal space would be
avoided where the incision, if extended upwards, would have no effect whatever
in facilitating the extraction of the stone or the egress of the urine; and
what is also of prime importance, the external opening would directly
correspond with the incision through the prostate and neck of the bladder. 2nd,
After the incision through the skin and superficial fascia is made, the
operator should separate as many of the deeper structures as will admit of it,
by the finger rather than by the knife; and especially use the knife cautiously
towards the extremities of the wound, so as to avoid the artery of the bulb,
and the bulb itself in the upper part, and the rectum below. The pudic artery
will not be endangered if the deeper parts be divided by the knife, with its
edge directed downwards and outwards, while its point slides securely along the
staff in the prostate. 3rd, The prostate should be incised sparingly, for, in
addition to the known fact that the gland when only partly cut admits of
dilatation to a degree sufficient to admit the passage of even a stone of large
size, it is also stated upon high authority that by incising the prostate and
neck of the bladder to a length equal to the diameter of the stone, such a
proceeding is more frequently followed with disastrous results, owing to the
circumstance that the pelvic fascia being divided at the place where it is
reflected upon the base of the gland and the side and neck of the bladder,
allows the urine to infiltrate the cellular tissue of the pelvis. [Footnote]

[Footnote: “The object in following this method,” Mr. Liston observes, “is to
avoid all interference with the reflexion of the ilio-vesical fascia from the
sides of the pelvic cavity over the base of the gland and side of the bladder.
If this natural boundary betwixt the external and internal cellular tissue is
broken up, there is scarcely a possibility of preventing infiltration of the
urine, which must almost certainly prove fatal. The prostate and other parts
around the neck of the bladder are very elastic and yielding, so that without
much solution of their continuity, and without the least laceration, the
opening can be so dilated as to admit the fore-finger readily through the same
wound; the forceps can be introduced upon this as a guide, and they can also be
removed along with a stone of considerable dimensions, say from three to nearly
five inches in circumference, in one direction, and from four to six in the
largest.”—Practical Surgery, page 510. This doctrine (founded, no doubt,
on Mr. Liston’s own great experience) coincides with that first expressed by
Scarpa, Le Cat, and others. Sir Benjamin Brodie, Mr. Stanley, and Mr. Syme are
also advocates for limited incisions, extending no farther than a partial
division of the prostate, the rest being effected by dilatation. The
experience, however, of Cheselden, Martineau, and Mr. S. Cooper, inclined them
in favour of a rather free incision of the prostate and neck of the bladder
proportioned to the size of the calculus, so that this may be extracted freely,
without lacerating or contusing the parts, “and,” says the distinguished
lithotomist Klein, “upon this basis rests the success of my operations; and
hence I invariably make it a rule to let the incision be rather too large than
too small, and never to dilate it with any blunt instrument when it happens to
be too diminutive, but to enlarge it with a knife, introduced, if necessary,
several times.”—Practische Ansichten der Bedeutendsten Chirurgische
Operationen. Opinions of the highest authority being thus opposed, in
reference to the question whether free or limited incisions in the neck of the
bladder are followed respectively by the greater number of fatal or favourable
results, and these being thought mainly to depend upon whether the pelvic
fascia be opened or not, one need not hesitate to conclude, that since facts
seem to be noticed in support of both modes of practice equally, the issue of
the cases themselves must really be dependent upon other circumstances, such as
the state of the constitution, the state of the bladder, and the relative
position of the internal and external incisions. “Some individuals (observes
Sir B. Brodie) are good subjects for the operation, and recover perhaps without
a bad symptom, although the operation may have been very indifferently
performed. Others may be truly said to be bad subjects, and die, even though
the operation be performed in the most perfect manner. What is it that
constitutes the essential difference between these two classes of cases? It is,
according to my experience, the presence or absence of organic
disease.”—Diseases of the Urinary Organs.]