710 THE VEINS. 



5. Deep Veins of the Leg. 



These are two in number : the anterior and posterior tibial. 



A. Anterior Tibial Vein. — Placed beside the homonymous artery, often 

 double, always very ample, this vein originates on the anterior face of the tarsal 

 articulations by means of several anastomosing roots, the principal of which is 

 formed by the deep metatarsal vein, that passes through the cuboido-cuneo- 

 scaphoid canal from behind to before. After crossing the fibular arch with the 

 artery, it joins the posterior tibial to constitute the popliteal vein. 



B. Posterior Tibial Vein. — This commences near the hollow of the hock, 

 in front of the calcis, by radicles which principally come from the two saphena 

 veins. It then ascends along its satellite artery, to open into the anterior vein 

 beneath the popliteal muscle. 



6. Superficial Veins of the Leg. 



These are the internal and external saphena. 



A. Internal Saphena Vein. — This vessel shows two roots — an anterior 

 and posterior (Fig. 389, 39, 40). 



The first proceeds from the internal metatarsal vein, the second from the 

 external. Both ascend, in converging towards each other, on the internal face 

 of the tibia, uniting into a single branch before reaching the thigh. 



This single branch — always very volimiinous — glides upwards on the sartorius 

 muscle, and terminates in a variable manner on reaching the groin : sometimes 

 it is insinuated into the interstice between the gracilis and sartorius, to join the 

 femoral vein, and at other times it ascends to the ring of the gracilis, to open 

 into the external pudic veins. 



B. External Saphena Vein. — It rises, by a short branch, outside the os 

 calcis, communicates, even at its origin, with the posterior root of the internal 

 saphena by means of a large reticular anastomosis thrown transversely in front 

 of the apex of the calcis ; and with the posterior tibial, by a large branch that 

 passes between the tibia and the flexor pedis perforans muscle. It follows the 

 external saphena nerve outside the gastrocnemius tendon, behind the exterual 

 head of the gastrocnemius muscle, and enters the popliteal vein, after joining the 

 femoro-popliteal vessel. 



7. Metatarsal Veins. 



These veins are three in number, and are distinguished as internal, externaU 

 and deep ; they proceed from the sesamoidean arch, which is formed by the 

 anastomosis of tlie two digital veins. 



A. Internal Metatarsal Vein. — This vessel, the most considerable of the 

 three, appears more particularly to continue the digital vein of the same side. 

 For the greater part of its extent it is placed with the internal plantar nerve, 

 along, and a little in advance of, the flexor tendons. Arriving near the tareus, 

 it deviates slightly to reach the anterior face of the tarsal articulations, and 

 there communicates — by a very large transverse branch — with the origin of the 

 anterior tibial vein ; afterwards it rises on the internal face of the leg, where it 

 constitutes the anterior radicle of the internal saphena vein. 



B. External Metatarsal Vein. — It occupies, outside the flexor tendons, a 

 position analogous to the preceding. Towards the superior extremity of the 



