Suprascapular neuropathy related to a glenohumeral joint cyst.

A man with shoulder pain and complaints of weakness had examination findings consistent with a suprascapular neuropathy with predominant involvement of the infraspinatus muscle. Electrodiagnostic studies confirmed an axon-loss suprascapular neuropathy with greater involvement of the infraspinatus muscle. Magnetic resonance imaging (MRI) demonstrated a large ganglion cyst originating from the glenohumeral joint. The clinical, electrodiagnostic, and radiologic evaluation of suprascapular neuropathy is discussed.