POSTERIOR TIBIAL ARTERY. 245 



tensor brevis muscle, and forms a sort of arch at the roots of 

 the metatarsal bones. It furnishes several ramifications to the 

 upper surface of the tarsus and the contiguous parts; amongst 

 them is an interosseal artery for each of the three outer interos- 

 seal spaces. These arteries communicate, by small anasto- 

 moses, with the arteries of the sole of the foot, both at the bases 

 and at the ends of the metatarsal bones, and terminate in front 

 by supplying the backs of the small toes. 



This artery is sometimes a branch of the tarsal. 



7. The Dorsal Artery of the Great Toe (Art. Dorsalis Hal- 

 lucis) arises from the anterior tibial at the root of the first me- 

 tatarsal bone. It runs along the superior face of the first me- 

 tatarsal interval, and having reached the anterior end of it, di- 

 vides into two branches, one of which goes to the back of the 

 great toe and the other to the tibial margin of the next toe. 



The Anterior Tibial, in its course from the ankle joint to the 

 base of the first metatarsal bone, is sometimes called Pedal (Jlr- 

 teria Pedicea;) at the posterior end of the first metatarsal inter- 

 val, being still of considerable size, it sinks down to the sole of 

 the foot, and joins itself to the external plantar artery at this 

 point. 



It frequently happens that the anterior tibial being small in 

 its course down the leg, is joined by the continued trunk of the 

 peroneal, which perforates the interosseous ligament somewhat 

 above the ankle joint. Afterwards the trunk formed by this 

 union, being of considerable size, follows the course and has 

 the distribution mentioned. 



The Posterior Tibial Artery (Mrleria Tibialis Postica) is 

 sometimes called, at its commencement, till it gives off the pe- 

 roneal, tibio-peroneal; it extends from the head of the tibia to 

 the sinuosity of the os calcis, in a line from the middle of the 

 ham to the internal ankle. It is at the tibial side of the back 

 of the leg, on the posterior face of the flexor longus digitorum 

 muscle; and covered by the fascia of the latter. In the two 

 superior thirds of its course, it is concealed behind by the gas- 

 trocnemius and the solseus muscle: in the inferior third, it is 

 at the internal margin of the tendo-achillis. At the ankle joint, 

 before it passes into the sinuosity of the os calcis, it is between 

 the tendon of the tibialis posticus and that of the flexor Ion- 



22* 



