402 ABDOMEN 



carried distally into the thigh behind the inguinal ligament, 

 to form the anterior part of the femoral sheath (vide p. 182); 

 (3) medial to the femoral vessels, where it is attached to the 

 ilio-pectineal line or pecten of the superior ramus of the 

 pubis behind the falx inguinalis (O.T. conjoined tendon), 

 with which it is partially blended. 



Annulus Inguinalis Abdominalis (Abdominal Inguinal Ring). 

 It has been noted that the transversalis fascia is pierced by 

 the spermatic cord. The opening through which it passes is 

 called the abdominal inguinal ring (O.T. internal abdominal 

 ring). This opening can only be defined from the front by 

 an artificial dissection viz. by dividing the infundibuliform 

 fascia around the cord and pushing it upwards with the 

 handle of the knife. The ring thus defined lies about half 

 an inch above the inguinal ligament, at a point midway 

 between the symphysis pubis and the anterior superior 

 spine of the ilium. Through the opening the dissector 

 can see the extra-peritoneal fat upon which the transversalis 

 fascia rests, and, just medial to the opening, he will notice 

 the inferior epigastric artery, pursuing its oblique course 

 upwards and medially, and shining through the fascia. If the 

 handle of the knife be now introduced into the ring and carried 

 laterally between the fascia and extra-peritoneal fat, the 

 attachments of the fascia to the inguinal ligament and to the 

 iliac crest can be very clearly shown. 



Canalis Inguinalis (Inguinal Canal). The dissector has 

 observed that the spermatic cord in the male and the round 

 ligament in the female pierce the abdominal wall above the 

 inguinal ligament. The passage which is formed for their 

 transmission receives the name of the inguinal canal. Now, as 

 this canal is a source of weakness to the abdominal wall, and 

 as it is in connection with it that inguinal hernia occurs, the 

 student will understand how necessary it is that he should 

 examine it carefully from all points of view. 



The inguinal canal is a narrow channel of about one inch 

 and a half in length. It begins at the abdominal inguinal 

 ring, which may be spoken of as its inlet, and ends at the 

 subcutaneous inguinal ring, which constitutes its outlet. It is, 

 consequently, very oblique, having a direction almost directly 

 medialwards, with a slight inclination downwards and for- 

 wards. So much for its length and direction ; its floor, its 

 anterior wall, and its posterior wall have still to be examined. . 



