270 SURGICAL ANATOMY OF 



neurosis which separates the superficial from the deep 

 flexors is to be divided on a director, and the posterior 

 tibial nerve drawn on one side ; the posterior tibial artery, 

 surrounded by venae comites, is seen lying on the flexor 

 longus digitorum. 



The nutritious artery is a branch of considerable im- 

 portance. Directed upwards towards the knee, it enters 

 the shaft of the tibia in a deep canal in the posterior as- 

 pect, about four fingers' breadth from the knee, and may 

 give rise to troublesome hemorrhage in amputation of 

 the leg at this part. 



The peroneal artery, generally regarded as a branch 

 of the posterior tibial, is very often of larger size. It is 

 very deep, and lying along the fibular surface of the leg, 

 has the following relations : In front, the tibialis posticus 

 and flexor longus pollicis ; externally, the fibula ; and be- 

 hind, the soleus, deep aponeurosis, and flexor longus 

 pollicis. This vessel is occasionally wounded in com- 

 pound comminuted fractures of the fibula. 



In fractures of the tibia and fibula, which take place 

 obliquely from above, downwards, and forwards, the 

 muscles of the calf cause the lower fragments to be drawn 

 upwards and backwards, and frequently the upper one 

 to protrude through the integument. With a view of 

 bringing the surfaces into apposition, the knee should be 

 bent to relax the opposing muscles, and extension made 

 from the knee and ankle (vide Ankle-joint). 



Fracture of the lower end of the fibula is usually asso- 

 ciated with fracture of the inner malleolus (Pott's frac- 

 ture), or rupture of the internal lateral ligament of the 

 ankle-joint, causing dislocation of the foot outwards. 

 The eversion of the foot is due to the action of the pero- 

 neus longus, whilst the heel is drawn upwards by the 



