Tibial Neuropathy

Excerpt

Tibial neuropathy refers to any dysfunction of the tibial nerve. The most common known association is tarsal tunnel syndrome, which is tibial neuropathy as it crosses through the tarsal tunnel at the level of the ankle. Although tarsal tunnel syndrome and tibial neuropathy can be used synonymously, they represent separate entities.

The tibial nerve originates from the sciatic nerve at around the level of the popliteal fossa. It travels down the posterior aspect of the lower leg and runs inferiorly on the tibialis posterior muscle with the posterior tibial artery and vein. The tibial nerve passes along the medial malleolus in the tarsal tunnel, which is covered by the flexor retinaculum.

Along with the tibial nerve, the tarsal tunnel contains the tendons of the tibial posterior, flexor digitorum longus, and flexor hallucis longus muscles, as well as the posterior tibial artery and vein. After passing through the tarsal tunnel, the tibial nerve branches into the medial and lateral plantar nerves, which provide innervation to the plantar aspect of the foot.

The tibial nerve in the lower leg, proximal to the tarsal tunnel, provides motor innervation to the gastrocnemius, soleus, popliteus, flexor hallucis longus, flexor hallucis digitorum, tibialis posterior, and plantaris muscles. The medial plantar nerve supplies the abductor hallucis, flexor digitorum brevis, flexor hallucis brevis, and the first lumbrical muscles.

The lateral plantar nerve supplies the rest of the muscles of the plantar surface of the foot. This includes the abductor digiti minimi, quadratus plantae, abductor hallucis, flexor digiti minimi brevis, plantar interossei, dorsal interossei, and lateral three lumbrical muscles of the foot.