Triplane fracture of the distal radius.

A case of triplane fracture of the distal radius is reported in a 13-year-old boy. This exceptional fracture showed displacement, and was healed by closed reduction and 6 weeks of external immobilization. Eighteen months later, the patient showed complete physeal arrest of the distal radius, with radio-ulnar length discrepancy but without any repercussion on wrist mobility. The patient was declared asymptomatic 3 years after the injury. Prompt, physiological physeal arrest reduces the potential of growth deformity. These fractures must be treated conservatively by closed reduction (if displacement exists) and external immobilization, just like a normal one-plane fracture. We may suppose that final radio-ulnar discrepancy could lead to a painful and symptomatic ulno-carpal conflict in adult life. The following characteristics can be associated with this rare fracture: (1) occurrence close to the end of the growth period, as in other types of triplane fractures; (2) evolution towards partial or complete growth arrest of the physis, not requiring treatment and (3) stability of the fracture after closed reduction. In the present case, as in the other reported cases, it may also be added that orthopaedic treatment has been the rule, in contrast with triplane fractures occurring in the distal tibia, in which surgical treatment is indicated.