Isolated neuropathy of the recurrent motor branch of the median nerve.

Unlike carpal tunnel syndrome, isolated neuropathy of the recurrent motor branch of the median nerve is a rare condition as a cause of thenar muscle wasting. A focused neurophysiological approach is mandatory to reach the proper diagnosis and start specific treatment early enough to prevent possible irreversible hand function disabilities. This is a description of 16-year-old female patient who presented with isolated thenar muscle wasting for 3 years. A focused neurophysiologic approach using abductor pollicis brevis and second lumbrical muscles for recording of median nerve motor conduction and index finger for sensory conduction proved isolated neuropathy of the recurrent motor branch of the median nerve.