The =posterior tibial artery= (A. tibialis posterior) is much the
smaller of the two terminals of the popliteal. It lies at first between
the tibia and the popliteus, then between that muscle and the deep and
inner heads of the deep flexor. Lower down it descends along the tendon
of the inner head, becomes superficial in the distal third of the leg,
and passes behind the tendon. At the level of the tuber calcis it forms
an ᔕ-shaped curve, runs downward along the deep flexor tendon
accompanied by the plantar nerves, and divides at the lower part of the
hock into internal and external plantar arteries. The collateral
branches are as follows: