AAEE case report #15: ulnar neuropathy at or distal to the wrist.

A 56-year-old woman developed insidiously progressive, painless weakness of her left hand. Clinical and electrodiagnostic abnormalities were limited to the motor function of the hand, with the hypothenar less affected than more distal ulnar muscles. Compression of the distal ulnar nerve by a ganglionic cyst was surgically relieved and there was postoperative improvement. The electrodiagnosis of ulnar neuropathy at or distal to the wrist is reviewed together with relevant anatomic and clinical aspects of these uncommon lesions.