Relations of Femoral Artery 455 



the overhanging vastus internus, and the roof of Hunter's canal ; 

 also the long saphenous nerve, which, like the sartorius, crosses it 

 obliquely from the outer side. 



To the outer side is the anterior crural nerve, and, lower down, 

 are its saphenous branch and the sartorius, also the vastus internus, 

 and, at the end of the canal, the superficial femoral vein. On the 

 inner side are the common femoral vein and the pectineus, then the 

 three adductors, and, further down, is the sartorius, which has 

 crossed it. 



Note. To the surgeon the most important relations of the artery 

 are the vein and the sartorius ; and, fortunately, by remembering the 

 position which the muscle occupies (which is sufficiently obvious) he 

 remembers also the situation of the vein, which is upon just the oppo- 

 site aspect of the artery. Thus, when the sartorius is entirely to the 

 outer side, as at the base of Scarpa's triangle, the vein is entirely to 

 the inner side. When the sartorius is gaining the front of the artery 

 from the outer side the vein is getting behind it from the inner side, 

 as towards the apex of the triangle. When the muscle is exactly over 

 the artery, as at the apex of the triangle, the vein is exactly behind 

 it ; and when, as in Hunter's canal, the sartorius is lying above and 

 to the inner side, the vein is beneath and to the outer side. Lastly, 

 when the muscle is quite to the inner side, as at the lower end of the 

 canal, the vein is quite to the outer side, in which relative position it 

 is found at the top of the popliteal space. 



The relationship of the long saphenous nerve to the artery is the 

 same as that of the sartorius. 



The branches of the common femoral artery are the three super- 

 ficial twigs which, coming through the cribriform fascia, pass between 

 the layers of the superficial fascia, towards, as their names respectively 

 denote, the epigastric region, over Poupart's ligament, the iliac region 

 (circumflexd), and the external ptidic region. The former branches 

 communicate with the deeper and larger vessels of the same name 

 (p. 370). The third branch passes to the scrotum or labium, and, 

 lying over the spermatic cord, is wounded in inguinal herniotomy 

 and in castration. A fourth branch, the deep external pudic, pierces 

 the fascia lata on the inner side of the thigh, and, ending like the last, 

 anastomoses with the superficial perineal artery. 



The superficial femoral artery gives off various muscular branches, 

 and, in Hunter's canal, the anastomotica magna. This important 

 branch divides into a superficial part, which leaves the canal through 

 the roof, in company with the saphenous nerve ; and a deep part, 

 which passes obliquely across the lower end of the femur, under the 

 quadriceps extensor, giving branches into the articulation, and anasto- 

 mosing on the inner side with the superior articular of the popliteal, 

 and on the outer side with the superior external articular, the recur- 

 rent tibial, and the descending branches of the external circumflex. 



