2 86 SURGICAL APPLIED ANATOMY. [Chap. xvi. 



well as upwards. It should be remembered that the 

 incision required to relieve a constriction is, if pro- 

 perly applied, of the most insignificant character. 



Femoral hernia. In this form of rupture the 

 gut leaves the abdomen through the femoral ring and 

 passes down into the thigh along the crural canal. 

 The name " crural canal " is given to the narrow 

 interval between the femoral vein and the inner wall 

 of the crural sheath. Like the inguinal canal, it is 

 a potential rather than an actual canal, and exists 

 only when the sheath has been separated from the 

 vein by dissection or by a hernia! protrusion of some 

 kind. The canal is funnel-shaped, about half an inch 

 in length, and ends opposite the saphenous opening. 

 Femoral hernise are always acquired, and possess a sac, 

 made by themselves out of the parietal peritoneum 

 covering the crural ring and its vicinity. The canal 

 is larger in women than in men, and thus it happens 

 that this species of rupture is much more common in 

 the former sex. The tendency to this hernia in 

 women appears also to be increased by the weakening 

 effects of pregnancy upon the abdominal walls. As 

 the gut descends it pushes in front of it its sac of 

 peritoneum and the septum crurale (the name given 

 to the subserous tissue that covers in the femoral ring) 

 and enters the crural sheath. The adhesions of the 

 sheath limit its downward progress when it has 

 travelled about half an inch, and it therefore passes 

 forwards through the saphenous opening, pushing 

 before it the cribriform fascia. It then receives a 

 covering from the superficial fascia and the skin. 

 Owing to the rigidity of the structures about the 

 femoral ring, the neck of the sac must always be 

 small. For similar reasons its dimensions while in 

 the femoral canal must of necessity be insignificant, 

 but when once it has escaped through the saphenous 

 opening the loose subcutaneous fasciae of the groin 



