88 Commentary on plates 35, 36, 37, & 38.
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.) ]
(Page 89)
Plate 39--Figure 1