[Os epilunatum is a rare cause of atraumatic impaired motility and wrist pain].

In this case report a 28-year-old man had a six-year history of atraumatic wrist pain. X-ray and MRI showed an accessory ossicle dorsal to the lunate, near the scapholunate ligament: an os epilunatum. Os epilunatum is a rare ossicle of the hand, and only one clinical case and few cadaveric studies have previously been reported. Resection was performed through a dorsal approach, without damaging the scapholunate ligament. Three months post-operatively the patient had increased motility of the hand and no pain.