MEDIAL SIDE OF THE THIGH 267 



placed on the medial side of the pectineus. It is somewhat 

 triangular in shape, being narrow at its origin and expanded 

 at its insertion. It arises by a short, but strong, tendon from 

 the anterior surface of the body of the pubis, immediately 

 below the pubic crest (Fig. 116), and it is inserted into 

 the medial lip of the linea aspera of the femur by a thin, 

 tendinous expansion. It is supplied by the anterior division of 

 the obturator nerve. It acts like the adductor brevis (p. 272). 



Dissection. Divide the adductor longus 25 mm. below its 

 origin. Turn the proximal part upwards and notice how the 

 flat tendon is so curved upon itself that it simulates the appear- 

 ance of a round tendon. Turn the distal portion towards the 

 femur, and secure its nerve of supply from the anterior division 

 of the obturator nerve, which lies posterior to the muscle. As 

 the femur is approached the muscle fibres will be found to 

 terminate in a thin aponeurosis, by which the muscle is attached 

 to the linea aspera. This aponeurosis of insertion is intimately 

 connected anteriorly with the vastus medialis and posteriorly 

 with the adductor magnus. Separate it from both as far as 

 possible ; especially from the adductor magnus, in order to 

 display the profunda vessels, which lie, in part of their course, 

 between the adductors longus and magnus. 



Art. Profunda Femoris. This large vessel is the chief 

 artery of supply to the muscles of the thigh. It arises, in the 

 femoral triangle, from the lateral and posterior aspect of the 

 femoral artery, about an inch and a half distal to the inguinal 

 ligament. At first it is placed on the iliacus, but, as it pro- 

 ceeds distally, it inclines medially, and thus it crosses posterior 

 to the femoral artery, and conies to lie on the pectineus. 

 Reaching the upper border of the adductor longus, it passes 

 posterior to that muscle, and is continued distally, close to the 

 body of the femur, in front of the adductor brevis and adductor 

 magnus. Numerous large branches spring from the profunda 

 femoris, so that it rapidly diminishes in size. Ultimately it 

 is reduced to a fine terminal twig, which turns backwards 

 through the adductor magnus, and receives the name of the 

 fourth perforating artery. The following are the relations of 

 the profunda femoris: (i) It lies anterior to the iliacus, 

 on the lateral side of the femoral artery. (2) It is anterior 

 to the pectineus and posterior to the femoral artery, but 

 separated from it by the femoral vein and the profunda femoris 

 vein. (3) It is anterior to the adductor brevis, and, more 

 distally, to the adductor magnus, and it is posterior to the 

 adductor longus, which separates it from the femoral vessels. 



