Magnetic resonance imaging features of subacute idiopathic brachial neuritis.

A 60-year-old man presented with sudden onset of left shoulder pain followed 2 weeks later by the development of left shoulder girdle weakness. A clinical and electrophysiological diagnosis of subacute idiopathic brachial neuritis was made. The MRI features of subacute muscular denervation in this patient are discussed and the relevant literature reviewed.