The Arteria Dorsalis Pedis
The arteria dorsalis pedis (Fig. 553), the continuation of the anterior tibial, passes forward from the ankle-joint along the tibial side of the dorsum of the foot to the proximal part of the first intermetatarsal space, where it divides into two branches, the first dorsal metatarsal and the deep plantar Relations—This vessel, in its course forward, rests upon the front of the articular capsule of the ankle-joint, the talus, navicular, and second cuneiform bones, and the ligaments connecting them, being covered by the integument, fascia and cruciate ligament, and crossed near its termination by the first tendon of the Extensor digitorum brevis. On its tibial side is the tendon of the Extensor hallucis longus; on its fibular side the first tendon of the Extensor digitorum longus, and the termination of the deep peroneal nerve. It is accompanied by two veins. Peculiarities in Size—The dorsal artery of the foot may be larger than usual, to compensate for a deficient plantar artery; or its terminal branches to the toes may be absent, the toes then being supplied by the medial plantar; or its place may be taken altogether by a large perforating branch of the peroneal artery. Position—This artery frequently curves lateralward, lying lateral to the line between the middle of the ankle and the back part of the first interosseous space. Branches—The branches of the arteria dorsalis pedis are: Lateral Tarsal.
First Dorsal Metatarsal.
The lateral tarsal artery (a. tarsea lateralis; tarsal artery) arises from the dorsalis pedis, as that vessel crosses the navicular bone; it passes in an arched direction lateralward, lying upon the tarsal bones, and covered by the Extensor digitorum brevis; it supplies this muscle and the articulations of the tarsus, and anastomoses with branches of the arcuate, anterior lateral malleolar and lateral plantar arteries, and with the perforating branch of the peroneal artery. The medial tarsal arteries (aa. tarseæ mediales) are two or three small branches which ramify on the medial border of the foot and join the medial malleolar net-work. The arcuate artery (a. arcuata; metatarsal artery) arises a little anterior to the lateral tarsal artery; it passes lateralward, over the bases of the metatarsal bones, beneath the tendons of the Extensor digitorum brevis, its direction being influenced by its point of origin; and its anastomoses with the lateral tarsal and lateral plantar arteries. This vessel gives off the second, third and fourth dorsal metatarsal arteries which run forward upon the corresponding Interossei dorsales; in the clefts between the toes, each divides into two dorsal digital branches for the adjoining toes. At the proximal parts of the interosseous spaces these vessels receive the posterior perforating branches from the plantar arch, and at the distal parts of the spaces they are joined by the anterior perforating branches, from the plantar metatarsal arteries. The fourth dorsal metatarsal artery gives off a branch which supplies the lateral side of the fifth toe. The first dorsal metatarsal artery (a. dorsalis hallucis) runs forward on the first Interosseous dorsalis, and at the cleft between the first and second toes divides into two branches, one of which passes beneath the tendon of the Extensor hallucis longus, and is distributed to the medial border of the great toe; the other bifurcates to supply the adjoining sides of the great and second toes. The deep plantar artery (ramus plantaris profundus; communicating artery) descends into the sole of the foot, between the two heads of the first Interosseous dorsalis, and unites with the termination of the lateral plantar artery, to complete the plantar arch. It sends a branch along the medial side of the great toe, and is continued forward along the first interosseous space as the first plantar metatarsal artery which bifurcates for the supply of the adjacent sides of the great and second toes.