Dramatic subperiosteal bone formation following physeal injury in patients with myelomeningocele.

We present five cases of dramatic subperiosteal bone formation following fracture of the distal femoral physis in children with myelomeningocele. These fractures often go unrecognized due to lack of displacement and/or pain. Children present with a swollen, warm extremity and often systemic signs of inflammation, but rarely any pain or history of trauma. The dramatic radiographic appearance can cause a diagnostic dilemma. We present these cases in order to familiarize the clinician with the oftentimes dramatic appearance of this injury.