136 TOPOGRAPHICAL ANATOMY OP 



The branches of the posterior tibial artery are : — 



(1) A. nntritia tibice. — The nutrient artery of the tibia leaves the 

 parent vessel as this emerges from beneath the popliteus muscle. 



(2) Rami musculares. — Numerous muscular branches are distributed 

 to the popliteus and the deep flexor muscles. 



(3) A. tar sea lateralis. — The lateral tarsal 1 artery is the smaller of 

 the two terminal branches of the posterior tibial. Passing between 

 the tibia and the combined tendon of the flexor hallucis longus and 

 tibialis posterior it gains the lateral aspect of the tarsus, over which 

 it ramifies. A slender twig, the recurrent tarsal artery (a. tarsea 

 recurrens), runs upwards on the lateral border of the tendo calcaneus, 

 and unites with a branch of the posterior femoral artery. 



(4) A. tarsea medialis. — The medial tarsal artery is so much larger 

 than the lateral vessel that it might be regarded as the true continua- 

 tion of the posterior tibial. Passing backwards from its point of 

 origin, the artery describes a double curve, with the first convexity 

 directed distalwards, and the convexity of the second curve looking in 

 a proximal direction. After the second curve has been formed the 

 medial tarsal artery follows the combined tendon of the flexor hallucis 

 longus and tibialis posterior to end, behind the tarsus, in the medial 

 and lateral plantar arteries. 



Small branches of the medial tarsal artery are distributed over the 

 medial surface of the tarsus. A larger branch, the recurrent tibial 

 artery (a. recurrens tibialis), leaves the second convexity of the medial 

 tarsal and runs in a proximal direction along the medial border of the 

 tendo calcaneus, where it is related to the tibial nerve. It unites with 

 the saphenous and posterior femoral arteries. 



Dissection. — The dissection of the anterior tibial and fibular regions 

 should be combined with that of the dorsum of the metatarsus and 

 digit. The combined dissection, while not being too complicated, per- 

 mits of a connected view of the muscle and tendons of this part of the 

 limb. 



During the removal of the tarsal fascia certain specialised bands 

 (transverse ligaments) should be retained in position. One of these 

 will be found a short distance proximal to the end of the tibia. By 

 the attachments of its extremities to the bone it forms a ring through 

 which the tendons of the extensor digitorum longus, tibialis anterior, 

 and peronreus tertius play. Another band crosses the tendon of the 

 long digital extensor just beyond the joint between the tibia and the 

 talus. One extremity of this transverse ligament is attached to the 

 calcaneus; the other blends with the lateral limb of the peronreus 

 tertius tendon of insertion. 



A third very definite transverse ligament has its ends attached to 



1 Tarsus [L.], Tupo-os (tarsos) [Gr.], any broad, flat surface ; for example, the 

 flat of the human foot. 



