7 he Leg. 367 



other tendons, the bloodvessels and the nerve, all pass be- 

 neath this ligament without any special sheath of synovial 

 membrane. 



The Bloodvessels The anterior tibial artery be- 

 gins at the lower border of the popliteus muscle, i.e., at 

 the termination of the popliteal. It passes to the front of 

 the leg and then down this surface to terminate, on the 

 dorsum of the foot, as the dorsalis pedis. 



Relations. In front, are the skin, superficial and 

 deep fasciae, while, in its lower third, it is crossed, from 

 without inwards by the extensor proprius hallucis. The 

 vessel lies in the interval between the tibialis anticus, in- 

 ternally, and the extensor longus digitorum and the ex- 

 tensor hallucis, externally. It has in front, also, the an- 

 terior annular ligament of the ankle joint, as well as the 

 anterior tibial nerve in its middle third ; behind, it lies, in 

 the upper two-thirds of its course, on the interosseous 

 membrane, and, in its lower third, on the front of the 

 tibia and the ankle joint ; externally, in its upper third, it 

 lies in contact with the extensor longus digitorum, and in 

 most of its lower two-thirds, with the extensor proprius 

 hallucis, while, for the distance of about one inch above 

 the ankle joint, the extensor longus digitorum again lies 

 next to it; internally, it has the tibialis anticus, with the 

 exception of the lower portion, where the extensor pro- 

 prius hallucis lies, for a short distance, in front or on its 

 inner side. 



Landmarks. The course of the artery corresponds 

 to a line drawn from the inner side of the head of the 

 fibula to a point midway between the two malleoli. Since 

 the artery begins about the lower border of the tubercle 

 of the tibia and comes almost directly to the front, the 

 landmark for its upper end, on the anterior surface of the 

 leg, will be indicated by the lower border of the tubercle, 



