[Neuralgic amyotrophy].

Neuralgic amyotrophy (NA) is a distinct peripheral nervous system (PNS) disorder characterized by sudden attacks of neuropathic pain, usually in a unilateral upper extremity, and patchy paresis with atrophy in the glenohumeral muscles. The lesion sites of NA are commonly considered to be upper brachial plexus (BP) and/or individual branches of the BP. The cause of NA remains unknown. Some evidence suggests a complex pathogenesis in NA that includes predisposition and susceptible PNS structures, and it can be triggered by infection, trauma, and strenuous exercise. NA is considered to be broad and encompasses a spectrum of atypical presentations, including involvement of the lower part of the BP, isolated nerves (anterior interosseous nerve or posterior interosseous nerve), or lumbosacral plexuses. Functional prognosis of NA is less favorable than previously assumed; however, specific therapy for patients with NA remains to be established.