Variation in the division of the tibial nerve: application to nerve blocks.

One hundred and twenty-six human cadaver lower extremities were dissected to determine the level of division of the tibial nerve into medial and lateral plantar nerves. While there is a considerable amount of variance in the level of division, there is a higher incidence of division proximal to the usual description. This is deep to the flexor retinaculum between the calcaneus and medial malleolus.