186 SURGICAL ANATOMY OF 



crural hernia, it must be remembered that the direction 

 of the crural canal is downwards, and slightly forwards 

 and outwards ; moreover, that, in order to relax the ori- 

 fices of this canal, the thigh must be flexed upon the 

 pelvis, adducted and rotated inwards. 



The course taken by a crural hernia is as follows : 

 First, passing into the femoral ring, it descends verti- 

 cally in the femoral canal as far as the saphenic opening ; 

 next, being here prevented from passing further along 



FIG. 31. 



Section of the structures which pass beneath the femoral arch. 1. Poupart's 

 ligament. 2, 2. Iliac portion of the fascia lata, attached along the margin of the 

 crest of the ilium, and along Poupart's ligament as far as the spine of the pubes 

 (3). 4. Pubic portion of the fascia lata, continuous at 3 with the iliac portion, 

 and passing outwards behind the sheath of the femoral vessels to its outer border 

 at 5, where it divides into two layers ; one is continuous with the sheath of the 

 psoas (6) and iliacus (7) ; the other (8) is lost upon the capsule of the hip-joint 

 (9). 10. The anterior crural nerve. 11. Gimbernat's ligament. 12. The femoral 

 ring within the femoral sheath. 13. Femoral vein. 14. Femoral artery; the 

 two vessels and the ring are surrounded by the femoral sheath. (From WILSON.) 



the sheath of the vessels, it is directed forwards and 

 subsequently upwards, upon the external pillar of the 

 opening and Poupart's ligament. 



