Nerve conduction studies in upper limbs of patients with cervical spondylosis and motor neurone disease.

Proximal conduction studies by F-wave technique, with conventional distal motor and sensory conduction were performed along the ulnar nerves of 20 patients each with cervical spondylotic radiculopathy and/or myelopathy and with classical motor neurone disease (MND). Such F-wave parameters as shortest F-latency, F-conduction velocity, conduction time and F-ratio were calculated. Twenty-five age- and sex-matched healthy volunteers acted as controls. Proximal slowing associated with sensory conduction abnormalities and normal distal motor conduction favored cervical spondylosis (CS). Distal slowing with a normal proximal motor and sensory conduction was associated with motor neurone disease.