250 THE INFERIOR EXTREMITY 



the twig which springs from it and pierces the fibrous capsule 

 of the joint; then clean the straight head of the rectus femoris 

 to its origin from the anterior inferior spine of the ilium, and 

 follow the reflected tendon backwards to the upper border of 

 the acetabulum where it is embedded in the fibrous stratum of 

 the capsule of the hip joint. Note that tha interval between 

 the tensor fasciae and the sartorius is a path by which the surgeon 

 gets easy access to the front of the hip joint without endangering 

 any structures of importance. Clean and define the anterior 

 borders of the glutaeus medius and minimus. The nerve to the 

 tensor fascias emerges between the closely apposed borders of 

 the two muscles and indicates the line of separation. Not 

 uncommonly the anterior border of the medius is blended with 

 the deep surface of the tensor fascias ; if that is the case, separate 

 the two muscles with the scalpel. 



Turn now to the medial side of the middle third of the thigh, 

 and pull the sartorius laterally. Posterior to it there is an 

 angular interval bounded laterally by the vastus medialis and 

 medially by the adductor longus above and the adductor magnus 

 below. The interval is crossed by a strong layer of fascia which 

 forms the roof of the adductor canal (Hunter'sj (Figs. 114, 115). 

 On the fascia lies some loose areolar - issue in which is embedded 

 the subsartorial plexus of nerves. The plexus is not always easily 

 demonstrable, but if the dissector is successful he will find that 

 it is formed by interlacing twigs from the medial cutaneous, 

 the saphenous, and the obturator nerves. Clean the plexus and 

 areolar tissue away and clean the fascial roof of the canal. It 

 is attached laterally to the vastus medialis, and medially to the 

 adductors magnus and longus. Its proximal extremity fades 

 away indefinitely at the apex of the femoral triangle, but at its 

 distal end it terminates in a sharp crescentic border which extends 

 from the vastus medialis to the adductor magnus, at the junction 

 of tha middle and distal thirds of the thigh. The saphenous 

 nerve accompanied by the saphenous branch of the arteria genu 

 suprema will be seen emerging from the canal behind the distal 

 crescentic border of the fascial roof. To display the contents 

 of the canal, divide the fascial roof by a vertical incision extending 

 from its proximal to its distal end, and then clean the contents, 

 which are the femoral artery, the femoral vein, the saphenous 

 nerve, and the nerve to the vastus medialis. 



M. Sartorius. The sartorius is a long slender muscle, 

 which arises from the anterior superior spine of the ilium and 

 the upper part of the notch on the anterior border of the bone 

 immediately below the spine. It crosses the front of the 

 proximal third of the thigh obliquely, and, gaining the medial 

 side of the limb, it takes a nearly straight course distally to a 

 point beyond the medial prominence of the knee. There it 

 turns forwards, and ends in a thin, expanded aponeurotic 

 tendon, which is inserted into the medial surface of the body 

 of the tibia, posterior to the tuberosity (Fig. 139, p. 322). 

 By its distal border the tendon is connected with the fascia 



