Fasciitis ossificans: imaging features, histology, and differential diagnosis

Ossifying fasciitis of the proximal lower extremity

Ossifying fasciitis is a rare benign tumor of heterotopic bone formation within fascial tissue. We present a case of a 23-year-old female with a nontraumatic painful mass of the left proximal thigh identified as ossifying fasciitis, a lesion that must be considered in the differential diagnosis of soft tissue tumors.