THE DORSAL ARTERY. 



845 



Fig. 743- 



Musculo- 

 cutaneous nerve 



THE DORSAL ARTERY OF THE FOOT. 



The dorsal artery of the foot (a. dorsalis pedis) (Fig. 743) is the continuation of 

 the anterior tibial beyond the ankle-joint. It extends to the proximal portion of the 

 first intermetatarsal space, where it receives the large fourth perforating branch of the 

 plantar arch, and is thence continued forward along the intermetatarsal space as the 

 a. dorsalis hallucis. 



Relations. — The dorsalis pedis is covered in the proximal portion of its course by 

 the anterior annular ligament, and is crossed just before it reaches the intermetatarsal 

 space by the tendon of the extensor brevis digitorum which passes to the great toe. It 

 rests successively upon 

 the anterior ligament of 

 the ankle-joint, the head 

 of the astragalus, the 

 astragalo-scaphoid liga- 

 ment, the dorsal surface 

 of the scaphoid bone, the 

 dorsal scapho-cuneiforni 

 ligament, and the in- 

 tercuneiform ligaments 

 which extend between 

 the middle and internal 

 cuneiform bones. Ex- 

 ternally it is separated 

 from the innermost ten- 

 don of the extensor lon- 

 gus digitorum and from 

 the extensor brevis digi- 

 torum by the inner termi- 

 nal branch of the anterior 

 tibial nerve, and inter- 

 nally it is in relation with 

 the tendon of the exten- 

 sor hallucis proprius. 



Branches. — In 

 addition to numerous cu- 

 taneous branches to the 

 skin of the dorsum of 

 the foot and muscnlar 

 branches to the extensor 

 brevis digitorum, the 

 dorsalis pedis gives rise 

 to the following vessels. 



I. The internal 

 tarsal branches (aa. 

 tarseae mediales) are one 



Tendon of 



tibialis anticus 



Branch of musculo- 

 cutaneous nerve 



Ant. tibial artery 

 Ant tibial nerve 



Tendon of extensor 



longus hallucis 



Dorsalis pedis artery 



Peroneus brevis 

 Peroneus longus 



/ 



Dissection showing relations of vessels and nerves in vicinity of left ankle; 

 portion of anterior annular ligament still in place. 



or more small vessels which pass o\'er the outer border of the foot, supplying the 

 integument and the tarsal articulations and anastomosing with the internal malleolai 

 and internal plantar arteries. 



2. The external tarsal branch fa. tarsea lateralis) arises opposite the head 

 of the astragalus and passes outward and forward over the scaphoid and cuboid 

 bones, under cover of the extensor brevis digitorum. It gives branches to that 

 muscle, to the skin, and to the tarsal articulations, and anastomoses with the external 

 malleolus and anterior peroneal arteries above, with the external plantar laterally, and 

 with the metatarsal below. 



3. The metatarsal branch (a. arcuata") arises over the internal cuneiform bone 

 and is directed at first laterally forward and then laterally over the bases of the four 

 outer metatarsal bones and beneath the tendons of the extensor longus and extensoi 



