2 78 INFERIOR EXTREMITY 



medial side of the leg are (i) the saphenous nerve ; (2) the 

 posterior branch of the medial cutaneous of the thigh ; and (3) 

 the medial calcanean nerves. 



The guide to the saphenous nerve is the great saphenous vein. 

 It may now be exposed in its entire course along the medial 

 side of the leg. The posterior branch of th'e medial cutaneous 

 nerve of the thigh proceeds distally a short distance posterior 

 to the preceding nerve. It usually ends about the middle of 

 the leg. The medial calcanean nerves are branches of the 

 posterior tibial nerve. Dissect for them in the interval between 

 the prominence of the heel and medial malleolus. They pierce 

 the ligamentum laciniatum (O.T. internal annular), nearer the 

 former than the latter, and their branches of distribution to the 

 skin of the heel and sole will be seen in a future dissection. 



In the middle line of the leg two nerves will be found, viz. 

 (i) the terminal part of the posterior cutaneous nerve of 

 the thigh, and (2) the medial cutaneous nerve of the calf. 

 They have both been previously seen in the dissection of 

 the fossa poplitea. The medial cutaneous nerve of the calf, 

 a branch of the tibial nerve, descends in the interval 

 between the two heads of the gastrocnemiiis and pierces the 

 deep fascia midway between the knee and ankle. A short 

 distance distal to this it is joined by the anastomotic peroneal 

 nerve, and then acquires the name of sural nerve. 



On the lateral side of the posterior aspect of the leg is the 

 anastomotic peroneal nerve, a branch of the common peroneal 

 nerve. It descends upon the lateral head of the gastro- 

 cnemius, and, perforating the deep fascia, unites with the 

 medial cutaneous nerve of the calf a short distance distal to 

 the middle of the leg, to form the sural nerve. The latter 

 has already been traced posterior to the lateral malleolus to 

 the lateral margin of the foot and little toe. 



Deep Fascia. A continuous view of the deep fascia, on the 

 posterior aspect of the leg, can now be obtained by removing 

 the remains of the superficial fat. Observe how thin and 

 transparent it is in the proximal part of the leg, and how it 

 thickens as it is followed distally towards the heel. At no 

 point, however, is it very dense. As it passes over the interval 

 between the heel and the medial malleolus it forms the 

 ligamentum laciniatum. It is continuous proximally with the 

 popliteal fascia, and a short distance distal to the knee, on 

 the medial side, it receives a reinforcement of fibres from 



