Artc:ies of Leg and Fact 491 



tibial ks2lf, and it m iv practically take i';s place ; sometimes this large 

 artery passes through as the anterior psroneal to become the dorsalis 

 p^dis. 



In addition to the p^roneal, the posterior tibial also gives off a 

 nulr'ent branch which runs downwards in the tibia ; tiiuscii lar branches ; 

 a communicating to join the corresponding branch from the peroneal, 

 and some infernal calcanean twigs which nourish the inner part of the 

 flap in Syme's amputation. 



Collateral ircuiation after ligation of the posterior tibial artery 

 below the origin of the peroneal would be carried on by numberless 

 muscular branches. Blood would also enter the empty trunk through 

 the communicating artery, and the other anastomoses frr m the pero- 

 neal ; through the plantar arch, and through other communications 

 with the anterior tibial and the dorsalis pedis. 



Ligatio?i of the peroneal artery is required in the case of a punc- 

 tured wound, when the surgeon would have the track of the original 

 wound to guide him. Should he be called upon, however, to tie the 

 artery in its continuity, when there was no wound to guide him, he 

 had better make a four-inch incision between the bellies of the gastro- 

 cnemius, and, having traversed that muscle, the soleus, and the second 

 layer of deep fascia, secure the artery just previous to its entering the 

 long flexor of the great toe. 



The internal plantar division of the posterior tibial artery runs 

 forward between the abductor hallucis and the flexor brevis digitorum, 

 and, arriving at the ball of the great toe as a small twig, ends by 

 anastomosing with the innermost digital branch. The internal 

 plantar is an unimportant trunk ; it takes no part in the formation of 

 the plantar arch. 



The external plantar artery corner off from the bifurcation of 

 the posterior tibial, under cover of the abductor hallucis. It is a large 

 artery, and, having passed outwards between the flexors brevis and 

 accessorius, runs forwards between the former muscle and the abduc- 

 tor minimi digiti to the base of the fifth metatarsal bone. From that 

 situation it curves inwards across the metatarsal bones to the root of 

 the first interosseous space, where it joins the branch from the dorsalis 

 pedis to form the plantar arch. In this latter bend the artery lies 

 deeply beneath the long flexor tendons and the lumbricals. 



The branches are calcanean, muscular, and cutaneous ; also three 

 posterior perforating, which mount through the roots of the three 

 outer interosseous spaces to join the interosseous branches of the 

 metatarsal artery, and four digital arteries, of which one runs along 

 the outer side of the little toe, whilst the others pass in the inter- 

 osseous spaces to divide at the three outer c'efts, to supply the toes, 

 and to inosculate by short anterior perforating branches with the end- 

 ings of the dorsal interosseous arteries. The innermost cleft, and the 

 inner side of the great toe, are supplied by the dorsalis pedis. 



