Compression neuropathies of the upper extremity.

Nerve compression syndromes of the upper extremity occur at predicable locations. The diagnosis of nerve compression or nerve entrapment is based on the neurologic and electrodiagnostic examinations. The anatomy, neurophysiology, and electrodiagnosis of nerve compression are discussed. Common and uncommon compression and entrapment syndromes of the upper extremity are described. Errors in diagnosis occur when the neurologic or electrodiagnostic examinations are incomplete or inaccurate.