772 -SURGICAL ANATOMY OF FEMORAL HERNIA. 



The communicating branch between the epigastric and obturator lies in front, 

 of the ring. 



The circumference of the ring is thus seen to be bounded by vessels in every 

 part excepting internally and behind. It is in the former position that the stric- 

 ture is divided in cases of strangulated femoral hernia. 



Fig. 386. Hernia. The Relations of the Femoral and Internal Abdominal Rings, 

 seeii from within the Abdomen. Right Side. 



The obturator artery, when it arises by a common trunk with the epigastric, 

 which occurs once in every three subjects and a half, bears a very important 

 relation to the crural ring. In some cases (fig. 387) it descends on the inner side 

 of the external iliac vein to the obturator foramen, and will consequently lie on 

 the outer side of the crural ring, where there is little danger of its being wounded 

 in the operation for dividing the stricture in femoral hernia. Occasionally, how- 



Variations in Origin and Course of Obturator Artery. 

 Fig. 387. Fig. 388. 



ever, this vessel curves along the free margin of Gimbernat's ligament in its 

 passage to the obturator foramen ; it would, consequently, skirt along the greater 

 part of the circumference of the crural canal, and cpuld hardly fail in being 

 wounded in the operation (fig. 388). 



Septum Crurale. The femoral ring is closed by a layer of condensed areolar 

 tissue, called, by J. Cloquet, the septum crurale. This serves as a barrier to the 

 protrusion of a hernia through this part. Its upper surface is slightly concave, 



