ANTERIOR TIBIAL ARTERY 



627 



THE LATER.AJL PLANTAR ARTERY 



The lateral plantar artery [a. plantaris lateralis] (figs. 501, 502) — the larger of 

 the two branches into which the posterior tibial divides beneath the laciniate 

 (internal annular) ligament — passes at first laterally and forward across the sole 

 of the foot to the base of the fifth metatarsal bone, where it bends medially, and 

 still running forward sinks deeply into the foot and terminates at the proximal end 

 of the first interosseous space by anastomosing with the deep plantar (com- 

 municating) branch of the dorsal artery of the foot. In its course to the fifth 

 metatarsal bone the artery runs in a more or less straight line obliquely across the 

 foot; whilst its deep portion, extending from the fifth metatarsal bone to the proximal 



Fig. 501. — The Plantar Arteries, Left Foot. 

 (From a dissection in the Museum of St. Bartholomew's Hospital.) 



Lateral calcanean branch 



Anastomosing branch of lateral 

 plantar 



Abductor digit! quinti 



Anastomotic branch 

 Lateral plantar artery 



Digital to lateral side of little toe 



Lumbrical muscle 

 Fourth metatarsal 



Third metatarsal - 

 Second metatarsal 



Anastomosis about interpha- 

 langeal joint 



Dorsal branch of plantar digital- 



Anastomosis of plantar digital arteries 

 around matrix of nail and pulp of toe 



Medial calcanean branches 



Cutaneous branch of medial 

 plantar 



Plantar aponeurosis, cut 



Abductor hallucis 



Medial plantar artery 

 Flexor digitorum brevis 



Superior branch of medial plantar 

 Flexor hallucis brevis 



First plantar metatarsal artery 



Plantar digital branch of first meta- 

 tarsal to toe 



Plantar digital branch of first meta- 

 tarsal to medial side of great toe 



Plantar digital branch of first meta- 

 tarsal to lateral side of great toe 



end of the first interosseous space, forms a slight curve with the convexity forward, 

 and is known as the plantar arch. The plantar arch is comparable to the deep 

 volar arch formed by the deep branch of the ulnar anastomosing with the radial 

 through the first interosseous space. This homology is at times more complete 

 in that the deep plantar (communicating) branch of the dorsalis pedis, the 

 homologue of the radial in the upper limb, takes the chief share in forming the 

 arch. The lateral plantar artery is accompanied by two veins. The course of 

 the artery is indicated by a line drawn across the sole of the foot from a point 

 midway between the tip of the medial malleolus and the medial tubercle of the 

 calcaneus to the base of the fifth metatarsal bone, and thence to the lateral side 

 of the base of the first metatarsal. 



The lateral plantar artery, besides the branches named below gives twigs to 

 supply the muscles between which it passes, and the tarsal joints. It also gives 



