[Non-traumatic circumscribed myositis ossificans in the femoral region]

The authors report the main clinical and radiographic aspects of non-traumatic circumscribed myositis ossificans in a 12 year-old child. These observations provide useful information for making a diagnosis. CT scan showed the presence of two distinct areas, a lucent central area and a dense outer area whose appearance suggest the presence of calcium. The main differential diagnosis concerned tumors in the soft bone tissue which necessitated regular clinical and paraclinical follow-up.