Heterotopic ossification of the hip after non-accidental injury in a child: case report.

Heterotopic ossification is bone formation that occurs in an abnormal soft tissue location, most commonly after trauma, head injury, and surgical procedures such as joint arthroplasty. We report a rare case of severe heterotopic ossification caused by nonaccidental injury in a 3-year-old child. To our knowledge, heterotopic ossification as a result of nonaccidental injury in children has been reported in only 2 other patients. Physicians should be aware of this rare presentation of nonaccidental injury, and nonaccidental injury should be considered in the differential diagnosis in children who present with heterotopic ossification.