Demonstrations Of The Origin And Progress Of Femoral Hernia Its Diagnosis The Taxis And The Operation

Sources: Surgical Anatomy

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 he 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, 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, 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, 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, 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, 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 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, 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, 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.]