dorsiflexor

Dorsiflexors are muscles that produce dorsiflexion of the foot at the ankle, moving the top of the foot toward the shin. They are primarily located in the anterior compartment of the leg and play a key role in walking by clearing the foot during the swing phase and stabilizing the ankle during stance.

The principal dorsiflexor is the tibialis anterior. Other contributors are the extensor digitorum longus, extensor hallucis longus, and, to a lesser extent, the peroneus tertius. Together they bend the ankle upward and, for the toe extensors, extend the toes; tibialis anterior also contributes to foot inversion, while peroneus tertius can assist eversion.

These muscles are innervated mainly by the deep peroneal nerve, a branch of the common fibular nerve. They originate in the shin region and their tendons cross the ankle anteriorly to insert on the dorsal foot and toe bases.

Clinically, weakness or injury of the dorsiflexors, particularly the deep peroneal nerve, can cause foot drop, resulting in difficulty lifting the front of the foot and a compensatory steppage gait. Evaluation involves resisted dorsiflexion and nerve testing; management may include physical therapy, ankle-foot orthoses, or surgical interventions in some cases.