Median nerve compression in the palm of the hand by an anomalously enlarged ulnar artery.

Median nerve compression in the carpal tunnel by a thrombosed persistent median artery and a large aberrant artery substituting for the radial artery has been described but there have been no reports of median nerve compression in the palm of the hand by an anomalously enlarged ulnar artery. A 46 year old man is described who presented with clinical and electrophysiological features consistent with a median neuropathy at the wrist but surgical exploration revealed median nerve compression in the palm of the hand by an anomalously enlarged palmar branch of the ulnar artery. This case highlights another treatable cause of median nerve compression and illustrates that symptoms suggestive of carpal tunnel syndrome may be produced by median nerve compression in the palm of the hand.