A test which measures muscle response to nerve stimulation. Used to evaluate muscle weakness and to determine if the weakness is related to the muscles themselves or a problem with the nerves that supply the muscles. 
Abnormal results may be seen in myasthenia gravis, polymyositis, carpal tunnel syndrome, amyotrophic lateral sclerosis, alcoholic neuropathy, cervical spondylosis, dermatomyositis, familial periodic paralysis, Guillain-Barre syndrome, Lambert-Eaton syndrome, Friedreich's ataxia, mononeuritis multiplex, peripheral neuropathy,sciatic nerve disease and a variety of peripheral nerve disorders.