1140 



SURGICAL AND TOPOGRAPHICAL ANATOMY 



A pouch of peritoneum having been gradually, after repeated straining, coughing, 

 etc., pushed through the weak spot, the femoral ring, further weakened perhaps, 

 together with all the parts in the femoral arch, by child-bearing, some extra efi'ort 

 will force intestine or omentum into this pouch and thus form a hernia. Thus 

 formed, femoral hernia passes at first downwards in the femoral canal as far as the 

 saphenous opening, but, as a rule, does not go farther downwards on the thigh, but 

 mounts forwards and upwards, and somewhat outwards, even reaching the level of 

 Poupart's ligament. The reasons for this change of position are — (1) The narrow- 

 ing of the femoral sheath, funnel-like, i.e. wide above but narrowed below; (2) 

 the unyielding nature of the lower margin of the saphenous opening; (3) the fact 

 that this margin and the outer border are united to the femoral sheath; (4) the 



Fig. 704. — Irregularities of the Obturator Artery. (After Gray.) 

 A 



Deep circumflex iliac artery — ix 



Ejcternal iliac artery 

 Ejcternal iliac vein 



Obturator /oram,er> 



Internal ring, uith spermatic 

 vessels cut short in it 



De^p epigastric artery 



Lympliatic gland in femoral 

 ring 



The obturator artery, given off" 

 from the external iliac uith the 

 deep epigastric, descends to gain 

 the obturator foramen, but at a 

 safe distance from, the femoral 

 ring 



B 



The obturator artery, coming off" 

 from the deep epigastric, takes 

 a course so near to the femoral 

 ring that it tvould very likely 

 be (lidded by the bistonry intro- 

 ductil from n-ithout to divide 

 the base of Gimbernat's liga- 

 ment, the cause of the constric- 

 tion 



constant flexion of the thigh; (5) the fact that vessels (chiefly veins) and lym- 

 phatics descend to the sa})henous opening, the veins to join the saphena vein, and 

 the lymphatics to join the deeper group: these descending vessels serve to loop 

 upwards or suspend a femoral hernia, and thus prevent its further course down- 

 wards. 



Coverings of a femoral hernia. — (A) At the upper or femoral ring it 

 obtains ])eritoneum, extra-] )erit()neal fat, and septum crurale. 



(B) In the canal, a coating of the femoral sheath. 



(C) At the external or superficial opening, further coverings of cribriform 

 fascia, skin, and superficial fascia are added. 



