A case of traumatic myositis ossificans of the iliopsoas muscle in a 13 year old ballet dancer is presented. A history of multiple minor injuries to the region of the left hip in addition to the radiographic appearance of calcification were indicative of ectopic bone formation. The lesion was explored surgically because of the clinical symptoms of the coexistant femoral hernia as well as to obtain biopsy material to exclude a soft tissue tumor. Histological examination demonstrated the zoning effect of myositis ossificans with patterns varying from a cellular central zone to a peripheral one of fairly well oriented bone. The patient remains symptom-free and no radiographic evidence of recurrence was observed four years postoperatively.