Parosteal lipoma of the proximal radius: a report of five cases.

Parosteal lipoma of the proximal radius is a benign, slow-growing tumor. It may cause compression of either the posterior interosseous or the superficial branch of the radial nerve. Surgical excision usually leads to complete recovery. Five cases of parosteal lipoma of the proximal radius are presented. X-ray films demonstrated a radiolucent mass in contact with the radius. Two patients had signs of posterior interosseous nerve compression, and two showed signs of superficial radial nerve compression. In one case the lipoma surrounded an exostosis arising from the proximal radius. The tumors were excised in four patients. The three patients with neurologic involvement recovered fully. One patient refused surgery, and posterior interosseous nerve paralysis developed.