How are fractures of the physis classified?
Physeal injuries are classified in the Salter-Harris classification, increasing in severity from I to V. Type I is a fracture through the physis. The fracture line in type II includes the metaphysis and physis. Type III fracture includes the epiphysis and the physis. Type IV fracture involves the metaphysis, physis, and epiphysis. Type V fracture is a crush injury of the physis. Follow-up for Salter-Harris fractures may include magnetic resonance imaging (MRI), which can delineate an abnormally fused physis in the healing phase that may need to be disrupted to allow future osseous growth.