THE ANTERIOR TIBIAL ARTERY. 469 



deeply placed at the upper part of the leg, where those muscles 

 are fleshy ; but it is comparatively superficial below, between their 

 tendons, and comes forward upon the tibia. At the bend of the ankle 

 it is covered by the annular ligament, and is crossed from without 

 inwards by the tendon of the extensor proprius pollicis. In its oblique 

 course downwards the anterior tibial artery lies at first close to the 

 interosseous ligament, and is then at a considerable distance from the 

 spine of the tibia ; but in descending it gradually approaches that ridge, 

 and towards the lower part of the leg is supported on the anterior surface 

 of the bone 



Relation to Veins and Nerves. — The anterior tibial artery is accompa- 

 nied by two veins (vente comites). The anterior tibial nerve, coming 

 from the outer side of the head of the fibula, approaches the artery at 

 some distance below the ])lace where the vessel appears in front of the 

 interosseous ligament. Lower down, the nerve for the most part lies in 

 front of the artery, but often changes its position from the one side of 

 the vessel to the other. 



Branches. — Besides numerous small muscular branches, the anterior tibial 

 arteiy furnishes the following-. 



(<?) The recurrent artery, given off as soon as the anterior tibial reaches the 

 front of the leg-, ascends through the fibres of the tibialis anticus, and. ramifying 

 on the outside and front of the knee-joint, anastomoses with the inferior articular 

 and other branches of the pophteal aiteiy. 



(*) The viallcolar arteries, two in number, external and internal, are given off 

 near the ankle-joint, but are veiy variable in size and mode of origin. The 

 internal branch passes beneath the tendon of the tibialis anticus to the inner 

 ankle, and communicates with branches of the posterior tibial artery. The 

 external branch passes outwards under the tendon of the common cntensor of 

 the toes, and anastomoses wdth the anterior division of the peroneal artery, and 

 also with some ascending or recuiTent branches from the tarsal branch of the 

 dorsal artery of the foot. — These malleolar arteries supply articular branches to 

 the neighbouiing joints. 



DORSAL ARTERY OF THE FOOT. 



The dorsal artery of the foot (dorsalis pedis), the continuation of 

 the anterior tibial artery, extends from the termination of that vessel 

 at the bend of the ankle, to the posterior end of the first metatarsal 

 space. At this spot it divides into two branches, of which one pro- 

 ceeds forwards in tlie first interosseous space, whilst the other dips into 

 the sole of the foot, and terminates by inosculating with the plantar 

 arch. The dorsal artery of the foot lies in the interval between the 

 tendon of the proper extensor of the great toe, and that of the long 

 extensor of the other toes ; and is covered by a deep layer of fascia, 

 which binds it to the parts beneath. Near its end it is crossed by the 

 innermost tendon of the short extensor of the toes. 



Two veins accompany this artery ; the anterior tibial nerve lies on 

 its outer side. 



Branches. — The principal branches of the dorsal arteiy of the foot 

 are directed outwards and forwards upon the tarsus and metatarsus, 

 and are named accordingly. Some small offsets also run obliquely 

 inwards, and ramify upon the inner side of the foot. 



(a) Tlie tarsal branch arises from the artery usually where it crosses 

 the scaphoid bone, but its point of origin varies in different instances. 



