Anatomy, Bony Pelvis and Lower Limb: Posterior Tibial Nerve

Excerpt

The posterior tibial nerve describes the distal end of the tibial nerve as it passes around the medial malleolus in the tarsal tunnel. Anatomically, the structure is a continuation its parent tibial nerve in a specific region of the distal extremity and does not represent a branch of the tibial nerve or a distinct structure. Accordingly, some texts will refer to it as the tibial nerve. Moreover, there is no anterior tibial nerve at the level of the foot or ankle. However, many authors and texts refer to the structure as the posterior tibial nerve due to its clinical significance. The tibial nerve is both a motor and sensory nerve is the largest distal extension of the sciatic nerve and is a branch of the lumbosacral plexus carrying spinal roots L4, L5, S1, S2, and S3. In the distal thigh, the tibial nerve splits from the sciatic nerve, passes through the popliteal fossa, runs under the arch of the soleus and continues distally on its undersurface to finally descend posterior to the medial malleolus, where it earns the distinction of the posterior tibial nerve, and into the foot as the medial and lateral plantar branches. The posterior tibial nerve is susceptible to entrapment in tarsal tunnel syndrome and can be manipulated with anesthesia to provide nerve blockade.