The Leg. 373 



third of the course of the vessel, lies to its inner side, 

 whereas, in the lower two-thirds, i.e., after crossing, it lies 

 to its outer side. The branches of this artery are : Mus- 

 cular, nutrient to the tibia, calcanean communicating with 

 the peroneal, the peroneal itself, which runs along the 

 fibular side of the leg, and the malleolar. 



Landmarks. Artery. A line drawn from the mid- 

 dle of the popliteal space, opposite the knee joint, to a point 

 midway between the centre of the convexity of the heel 

 and the tip of the internal malleolus, corresponds to the 

 direction of the lower two-thirds of the posterior tibial 

 artery, whereas, the upper third is represented by a 

 slightly curved line, with its convexity outwards, drawn 

 downwards, from a point, on the posterior surface of the 

 leg, on a level with the lower part of the tubercle of the 

 tibia, to join the former line about two inches below this 

 point. Landmarks for the veins. The posterior tibial 

 veins correspond to the above lines for the artery, since 

 these veins lie one on either side of that vessel. For the 

 external saphenous vein. Draw a line from the centre of 

 the leg, on a level with the styloid process of the fibula, to a 

 point midway between the external malleolus and the heel. 

 This represents the superficial part of the vein, but, at the 

 upper part of the leg, this vessel, after piercing the deep 

 fascia runs for a distance of one and a half inches vertical- 

 ly upwards, before emptying into the popliteal vein. Land- 

 marks for the nerves. The posterior tibial nerve may be 

 represented by a line starting, as in the case of the artery, 

 from the middle of the popliteal space opposite the level 

 of the knee joint and drawn, downwards, to a point about 

 a quarter of an inch external to midway between the cen- 

 tre of the convexity of the heel and the tip of the internal 

 malleolus. 



