Part 33 (1/2)

O. Anterior crural nerve.

P. The hernia within the crural ca.n.a.l.

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.

[Ill.u.s.tration: Abdomen, showing bone, blood vessels and other internal organs.]

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 ca.n.a.l, 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 s.c.r.o.t.u.m. The femoral hernia, commencing on a level with, 5, the femoral arch, descends the femoral ca.n.a.l, 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 s.c.r.o.t.u.m, 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.

[Ill.u.s.tration: Abdomen, showing bone, blood vessels and other internal organs.]

PLATE 45.--FIGURE 1

PLATE 45, Fig. 2.--There exists a very evident a.n.a.logy between the ca.n.a.ls through which both herniae pa.s.s. 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 ca.n.a.l, 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.

[Ill.u.s.tration: Abdomen, showing bone, blood vessels and other internal organs.]

PLATE 45.--FIGURE 2

PLATE 45, Fig. 3.--The peritonaeum, 2, 3, closes the femoral ca.n.a.l, 12, at the femoral ring, in the same way as this membrane closes the inguinal ca.n.a.l 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 ca.n.a.l, 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.

[Ill.u.s.tration: Abdomen, showing bone, blood vessels and other internal organs.]

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 s.p.a.ce 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 ca.n.a.l) that the hernia may more readily pa.s.s. The peritonaeum, 2, and crural septum, 13, form at this place the only barrier against the protrusion of the bowel into the ca.n.a.l.