1022 SURGICAL ANATOMY OF HERNI^E. 



the margin of the muscle with its tendon has a semicircular direction with 

 respect to the aperture. 



The tendinous fibres in which the fleshy parts of the two preceding 

 muscles end, are connected together so as to form one layer, which is named 

 the "conjoined tendon of the internal oblique and transverse muscles." 

 This tendon is fixed to the crest of the pubes in front of the rectus muscle, 

 and likewise to the pectineal ridge. It is thus behind the external abdo- 

 minal ring, and serves to strengthen the wall of the abdomen where it is 

 weakened by the presence of that opening. 



A band of tendinous fibres, directed upwards and inwards over the 

 conjoined tendon in a triangular form, gives additional strength to the 

 abdominal wall in the same situation, but the fibres of this structure are 

 often very indistinct. 



Where the spermatic cord is in apposition with the preceding muscle, 

 the cremaster muscle of the testis descends over it. The fibres which com- 

 pose this muscle are, from their colour, more easily distinguished than the 

 other investments of the cord ; and this is especially the case in robust 

 persons ; or when they are hypertrophied, as sometimes happens in cases 

 of long-standing hernia. The outer part of the cremaster is much larger 

 than the portion connected with the pubes ; and the latter is sometimes 

 absent (p. 253). 



When observed in different bodies the lower parts of the internal oblique and 

 transverse muscles present some differences in their physical characters as well as 

 in the manner in which they are disposed with respect to the spermatic cord. 

 Thus : 



a. The transversalis, in some cases, is attached to but a small part of Poupart's 

 ligament, and leaves, therefore, a larger part of the abdominal wall without its sup- 

 port. On the other hand, that muscle may be found to extend so low clown as to 

 cover the internal abdominal ring together with the spermatic cord, for a short space. 

 Not unfrequently the fleshy fibres of the two muscles are blended together as well as 

 their tendons. 



6. Cases occasionally occur in which the spermatic cord, instead of escaping beneath 

 the margin of the internal oblique, is found to pass through the muscle, so that 

 some muscular fibres are below as well as above it. And examples of the transversalis 

 being penetrated by that structure in the same manner are recorded.* 



c. In his latest account of the structure of these parts Sir A. Cooper described the lower 

 edge of the transversalis as curved all round the internal ring and the spermatic cord. 

 " But the lower edge of the transversalis has a very peculiar insertion, which I have 

 hinted at in my work on Hernia. It begins to be fixed in Poupart's ligament, almost 

 immediately below the commencement of the internal ring, and it continues to be in- 

 serted behind the spermatic cord into Poupart's ligament as far as the attachment of 

 the rectus."f With this disposition of its fibres, the muscles would, in the opinion of 

 the last-cited authority, have the effect of a sphincter, in closing the internal ring, 

 and would thus tend to prevent the occurrence of hernia. But the principal object 

 with which the attention of surgeons has been fixed on the muscles in this situation, 

 is in order to account for the active strangulation of hernial protrusions at the internal 

 abdominal ring, and in the inguinal canal. 



Fascia transversalis. This membrane is described as part of the general 

 lining of the abdominal walls (p. 258). Closely connected with the trans- 

 versalis muscle by means of the areolar tissue interposed between the fleshy 

 fibres of the muscle, it is united below to the posterior edge of Poupart's 



* Eecherches Anatomiques sur les Hermes, &c., par J. Cloquet, p. 18 and 23. Pans, 

 1817. Inguinal and Femoral Heruiae, by G. J. Guthrie, plate I. London, 1833. 



f* Observations on the Structure and Diseases of the Testis, second edition, p. 36. Ed. 

 by Bransby B. Cooper, F.R.S. London, 1841. 



