476 THE INFERIOR EXTREMITY 



tendo calcaneus and the medial malleolus. The commencement 

 of the artery is on the same level as the tibial tuberosity. At 

 first it lies on the tibialis posterior, but near the ankle-joint it 

 is placed on the tibia between the flexor hallucis longus and the 

 flexor digitorum longus tendons. It terminates under cover of 

 the laciniate ligament by dividing into the lateral and medial 

 plantar arteries. 



Ligature of the posterior tibial artery is usually carried out 

 from the medial side, in order to avoid injuring the superficial 

 group of muscles. The incision is made a finger's breadth 

 behind the medial border of the tibia in its proximal third, and 

 retraction of the skin and fasciae exposes the free border of the 

 medial head of the gastrocnemius, which overlaps the origin of 

 the soleus from the medial border of the tibia (p. 474). The 

 wound is deepened through the soleus, exposing the strong 

 fascia which covers the deep muscles. After this fascia has been 

 carefully split, its lateral part is raised from the underlying 

 muscles, and the posterior tibial artery with its venae comites 

 is exposed, lying on the tibialis posterior. In the proximal third 

 of the leg the tibial nerve lies close to the medial side of the 

 artery, and must be avoided when the ligature is applied. 



The Tibial Nerve passes distally through the posterior 

 compartment in close relation to the posterior tibial vessels. 

 At first it lies on their medial side, but as it descends it crosses 

 them superficially and lies on their lateral side at the ankle. 

 It gives off branches of supply to the deep muscles (p. 475) and 

 terminates under the laciniate ligament by dividing into the 

 lateral and medial plantar nerves. 



The Peroneal Artery arises from the posterior tibial soon after its com- 

 mencement and runs distally in association with the flexor hallucis longus. 

 It lies to the lateral side of the posterior tibial artery and, just proximal to 

 the ankle-joint, gives off a perforating branch which pierces the interosseous 

 membrane and descends in front of the lateral malleolus. 



The Surgical Approach to the Tibia, whether for 

 exploration or for resection, is carried out along the medial 

 surface of the bone. The incision is vertical and is carried down 

 to the periosteum, care being taken to avoid injuring the 

 saphenous nerve and the great saphenous vein as they lie in 

 front of the medial malleolus. Resection of the whole diaphysis, 

 or of a portion of it, may be carried out in the manner already 

 described in the case of the humerus (p. 39). Along the 

 interosseous crest and near the epiphyseal cartilages the 

 periosteum is more adherent than it is elsewhere, and it is 



