Entrapment of Medial Plantar Nerve/’Joggers foot’
Usually occurs where the nerve is bound by a fascial sling (Master knot of Henry) between the medial aspects of the talus and navicular.
Unclear – may be an excessively pronated foot increasing tension on nerve (almost all have a pronated rearfoot). It has been suggested that higher arched foot orthoses may predispose to the problem.
Sharp, burning and radiating pain from the posterior arch area towards the first and second toes. Tenderness or pain on palpation above edge of abductor hallucis muscle in medial arch area. May be able to elicit Tinnel’s sign by tapping with finger. Sensory changes are not common, but can get numbness under medial toes.
Differential diagnosis – tendonitis of flexor hallucis longus and/or flexor digitorum longus – use resisted flexion or passive hyperextension of toes.
Orthoses for excessive pronation (may need to be modified to avoid pressure on area of entrapment); activity modification; NSAID’s; cortisone injection; surgical release of the fascia.