Myositis ossificans circumscripta (MOC) is a benign proliferation of fibrous tissue with large amounts of bone within soft tissues. Its clinical and radiological course is described and the value of CT and MR imaging is emphasized. Differential diagnosis includes soft tissue hematoma, infection or tumor. Florid reactive periostitis of the phalanges, turret exostosis, bizarre periosteal osteochondromatous proliferation in the hand and fibro-osseous pseudotumor of the digits are also described.