The tibial nerve is a component of the sciatic nerve. It is formed from the anterior divisions of the sacral plexus.
The tibial nerve travels in the posterior leg with the posterior tibial artery, in the fascial plane between the superficial and deep muscle groups. It passes posterior to the medial malleolus at the ankle ("Tom, Dick and very nervous Harry").
The tibial nerve provides motor innervation to the muscles of the posterior compartment of the leg (both superficial and deep).
The tibial nerve provides sensory innervation to the posterior aspect of the leg (via its contribution to the sural nerve) and the sole of the foot.
The tibial nerve terminates by bifurcating into the medial and lateral plantar nerves in the sole of the foot.
Injury to the tibial nerve typically produces: loss of plantarflexion of the foot, loss of flexion of the toes and weakened inversion of the foot; sensory loss over the territories described above.