512 A MANUAL OF ANATOMY 



The metatarsal artery arises on a level with the bases of 

 the metatarsal bones, over which it passes on its way to the outer 

 border of the foot, being under cover of the extensor brevis 

 digitorum. At the outer border it anastomoses with the tarsal 

 and external plantar arteries. The vessel forms a slight arch 

 with the convexity directed forwards. From the concavity of 

 the arch a few recurrent branches are given off to the tarsal 

 articulations. From the convexity three dorsal interosseous 

 arteries- are given off, which pass forwards over the outer three 

 interosseous spaces. Kt the level of the metatarso-phalangeal 

 joints each divides into two dorsal collateral digital arteries, which 

 supply the contiguous sides of the second and third, third and 

 fourth, and fourth and fifth toes. The most external dorsal inter- 

 osseous artery, before it divides into its two collateral branches, 

 furnishes a single dorsal digital artery to the outer side of the fifth 

 or little toe. At the proximal end of the second, third, and fourth 

 interosseous spaces the three dorsal interosseous arteries (in them- 

 selves small) are reinforced each by a posterior perforating artery, 

 the three posterior perforating arteries being branches of the plantar 

 arch. At the distal end of these interosseous spaces the three 

 dorsal interosseous arteries are usually further reinforced each by 

 an anterior perforating artery, the three anterior perforating arteries 

 being branches of the three compound plantar digital arteries from 

 the plantar arch. 



The arteria dorsalis hallucis is the first dorsal interosseous artery. 

 Arising from the terminal part of the dorsalis pedis artery, it 

 continues the direction of that vessel, and passes forwards over 

 the first interosseous space. On reaching the cleft between the 

 great toe and the second it divides into two dorsal collateral digital 

 branches for the supply of the contiguous sides of these two toes, 

 and it furnishes a small single dorsal digital artery for the supply 

 of the inner side of the great toe. The dorsalis hallucis artery is 

 not reinforced by any posterior perforating branch. Before, how- 

 ever, dividing into its digital branches it receives an anterior per- 

 forating artery, which is derived from the arteria magna or princeps 

 hallucis in the sole. 



The dorsal digital arteries as they pass along the sides of the toes 

 communicate with each other across their dorsal aspects, and also 

 with the corresponding plantar digital arteries. 



The plantar or perforating artery will be described in connection 

 with the sole of the foot. 



Varieties of Dorsalis Pedis Artery— i. Origin.— The vessel maybe the con- 

 tinuation of the anterior peroneal artery. 



2. Course. — The vessel often describes a considerable curve outwards before 

 it reaches the proximal end of the first interosseous space. In these cases 

 the artery may terminate at the back of the second interosseous space instead 

 of the first. 



3. Branches. — There is considerable deviation from the normal in respect 

 of branches. The branch most affected is the metatarsal artery. This may 

 arise in common with the tarsal branch. The metatarsal arch is often very 



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