Conduction Study of Dorsomedial Cutaneous Nerve to the Great Toe

ABSTRACT

OBJECTIVE: The dorsomedial cutaneous nerve (DMCN) to the great toe is a branch of the medial dorsal cutaneous nerve, which originates from the superficial peroneal nerve. The objective of this study is to standardize the electrodiagnostic technique, and to investigate the usefulness of dorsomedial cutaneous nerve (DMCN) conduction study in patients with peripheral neuropathy. METHOD: Sixty two legs in 31 normal adults and 56 legs in 28 patients with the clinical signs and symptoms as well as electrodiagnostic evidences of peripheral neuropathy were evaluated with the DMCN conduction study. The stimulating electrode was placed over the lateral 1/3 between medial and lateral malleoli and the active electrode was placed over 12 mm medial and 10 mm proximal to the extensor hallucis longus tendon over the 1st metatarsophalangeal joint. RESULTS: The mean values of DMCN conduction study in normal adults were 2.95+/-0.47 msec for onset latency, 3.58+/-0.43 msec for peak latency, 6.67+/-2.87microvolt in amplitude, and 12.96+/-1.17 cm for distance from active electrode to stimulation point. There were statistically significant differences between normal and patients groups in all parameters except the distance. CONCLUSION: A method for DMCN conduction study was introduced which could be used as a valuable technique for the early evaluation of peripheral neuropathy.