The posterior tibial extends from the lower border of the popliteus to a point almost midway between the medial malleolus and the calcaneum. Here, beneath the medial annular ligament (lig. laciniatum) it divides into the medial and lateral plantar nerves. In the calf it accompanies the posterior tibial vessels in the interval between the superficial and deep flexors. At first it lies on the medial side of the vessels, but about the middle of the leg it crosses to their lateral side.
(a) Muscular, to the tibialis posticus, flexor longus digitorum, and flexor longus hallucis.
(b) Articular, to the ankle-joint.
(c) Cutaneous, (calcaneal) pierce the medial annular ligament to supply the skin of the heel and posterior part of the sole of the foot.