234 ANATOMY OF THE LOWER EXTREMITY. 



Upon the fascia lata, thus exposed, will be found a numbei 

 of cutaneous nerves, on the inside, derived from the obtu- 

 rator nerve, on the outside from the external cutaneous 

 nerve (p. 199), and in the middle from the middle posterioi 

 cutaneous branch of the lesser sciatic nerve (p. 230). A1 

 the lower part of the thigh, the external saphena vein, 

 ascending from the foot along the median line of the cali 

 of the leg, may be seen penetrating the popliteal space 

 join the popliteal vein. 



The fascia lata is to be removed and the muscles are to be dissected. 

 The sciatic nerve and its divisions are to be particularly respected. 



The posterior femoral muscles will be found supplied 

 with arteries from the circumflex and perforating branches 

 of the profunda artery. 



The BICEPS MUSCLE is the most external of this region, 

 and, in common with the two muscles to be next described, 

 is covered in at its upper part by the glutens maximus. It 

 arises from the tuberosity of the ischium by a tendon, only 

 artificially separable from the other muscles arising at that 

 point, and also from the femur by a second head attached 

 to the linea aspera ; these two heads unite to be inserted 

 lay a round tendon into the head of the fibula and outer 

 tuberosity of the tibia. This tendon forms the outer ham- 

 string. 1 



The SEMI-TENDINOSUS MUSCLE lies upon the inner side of 

 the posterior femoral region. At its origin from the tuber- 

 osity of the ischium, and for some distance below it, it is 

 not easily separable from the biceps; it forms a compara- 

 tively short and stout belly, terminating in a long tendon, 

 which is inserted into the inner surface of the tibia below 

 the tendon of the gracilis, both of these tendons being 

 covered in by the expanded insertion of the sartorius. 



The SEMI-MEMBRANOSUS MUSCLE lies beneath the two pre- 

 ceding muscles, and derives its name from the membrani- 

 form tendon which characterizes its origin. It arises from 

 the tuberosity of the ischium, in common with the biceps 

 and semi-tendinosus muscles, and is inserted by a tendon 

 which has three different points of attachment, viz : an 

 internal, to the inner tuberosity of the 'tibia; a middle 



1 The student can assist his memory to retain the fact that the 

 biceps forms the outer hamstring, by the first two letters in the word 

 Boston. (13. 0. biceps, outer.) 



