Distal neuralgic amyotrophy

Abstract

Neuralgic amyotrophy consists of severe pain around the shoulder and arm followed by weakness in one or several muscles of the same area. We describe four patients with distal neuralgic amyotrophy in whom acute, severe, and transient pain around the shoulder or arm was followed by weakness of the forearm and hand muscles only. Minor sensory symptoms were present in only one patient. The presence of structural lesions causing the extent of the forearm and hand motor deficit was excluded by ancillary examinations. Electrophysiological studies showed a motor axonopathy and minimal sensory axonopathy. A follow-up of 2 years or longer showed either spontaneous improvement or residual motor deficit. Unfamiliarity with a clinically distal localization of neuralgic amyotrophy may result in misdiagnosis of lower cervical (poly)radiculopathy in view of the distal localization of the motor deficit and the high prevalence of coincidental abnormalities of the lower cervical spine on plain radiography, computed tomography, or magnetic resonance imaging.