Sensory conduction velocity of plantar digital nerves in Morton's metatarsalgia.

The orthodromic sensory conduction velocity of the plantar interdigital nerves were measured with needle electrodes in 28 healthy subjects. The stimulating needle electrodes were placed close to the shaft of the proximal phalanx of the toe, and the recording needle electrode was placed behind the medial malleolus. We examined six subjects with clinical symptoms of entrapment of the common plantar digital nerve (Morton's metatarsalgia). Five of the subjects later had surgery. The conduction velocities of the affected interdigital nerves were abnormally slow. The method is technically simple, but more painful than conventional conduction studies.