306 PERONEAL ARTERY. 



The Posterior Tibial Artery 



After parting with the anterior tibial, sends off the Peroneal 

 or Fibular, as has been already stated, and then continues on 

 the back of the tibia, behind the internal ankle, to the sole of 

 the foot. 



The Peroneal or Fibular Artery 





 Is not commonly so large as either of the two other arteries 



of the leg, nor is it so constant. It passes down very near the 

 internal edge of the fibula. It is in contact, for some distance, 

 with the tibialis posticus muscle, and is anterior to the soleus 

 and the flexor pollicis longus ; it sends branches to the contigu- 

 ous muscles. After it has passed along two-thirds of the length 

 of the fibula, it frequently, but not always, divides into an ante- 

 rior and a posterior branch. 



The Anterior Peroneal soon perforates the interosseous liga- 

 ment, and passing down some distance on its anterior surface, 

 continues to the ankle and upper surface of the foot. It gives 

 ramifications to all the contiguous parts in its progress, and 

 anastomoses with some of the small ramifications of the tibialis 

 antica. 



The Posterior Peroneal Branch is the continuation of the 

 main trunk. It passes behind the external malleolus, and rami- 

 fies upon the external side of the foot. 



The Posterior Tibial artery passes down, inclining rather 

 obliquely inwards, between the gastrocnemius internus, which 

 is posterior to it, and the tibialis posticus and flexor digitorum, 

 which are anterior to it. Upon the leg it gives off many small 

 branches, one of which, termed the Arteria Nutritia Tibia, 

 comes off high up,* and, after ramifying as it descends, sends a 

 branch to the medullary foramen of the tibia. 



At the lower part of the leg, the Posterior Tibial is situated 

 rather superficially between the tendo Achillis and the tibia. 

 It proceeds thence behind the internal ankle in a deep situa- 

 tion, covered by an annular ligament, and passes between the 



* This artery sometimes comes off from the popliteal. 



