DIRECT INGUINAL HERNIA. 



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below by the grooved border of Poupart's ligament ; and at each ex- 

 tremity by one of the abdominal rings, the internal ring at the inner 

 termination, the external ring at the outer extremity. These relations 

 may be more distinctly illustrated by the following plan 



In Front. 



Aponeurosis of 

 external oblique. 



Above. 



Lower borders of internal oblique 

 and transversalis muscle. 



Spermatic canal. 



Behind. 



Transversalis fascia. 

 Conjoined tendon of 

 internal oblique and 

 transversalis. 



Below. 



Grooved border of 

 Poupart's ligament. 



There are three varieties of oblique inguinal hernia: common, con- 

 genital, and encysted. 



Common oblique hernia is that which has been described above. 



Congenital hernia results from the nonclosure of the pouch of peri- 

 toneum carried downwards into the scrotum by the testicle, during 

 its descent in the foetus. 



The intestine at some period of life is forced into this canal, and de- 

 scends through it into the tunica vaginalis where it lies in contact with 

 the testicle ; so that congenital hernia has no proper sac, but is con- 

 tained within the tunica vaginalis. The other coverings are the same 

 as those of common inguinal hernia. 



Encysted hernia (hernia infantilis, of Hey) is that form of protrusion 

 in which the pouch of peritoneum forming the tunica vaginalis, being 

 only partially closed, and remaining open externally to the abdomen, 

 admits of the hernia passing into the scrotum, behind the tunica vagi- 

 nalis. So that the surgeon in operating upon this variety, requires 

 to divide three layers of serous membrane ; the first and second layers 

 being those of the tunica vaginalis ; and the third the true sac of the 

 hernia. 



DIRECT INGUINAL HERNIA has received its name from passing di- 

 rectly through the external abdominal ring, and forcing: before- it the 

 opposing parietes. This portion of the wall of the abdomen is 

 strengthened by the conjoined tendon of the internal oblique and 

 transversalis muscle, which is pressed before the hernia, and forms one 

 of its investments. Its coverings are, the 



Integument, 

 Superficial fascia, 

 Intercolumnar fascia, 

 Conjoined tendon, 

 Transversalis fascia, 

 Peritoneal sac. 



