[Scaphoid fracture in motocross riders].

Motocross racing is a demanding motorcycling discipline with significant physiological and psychological demands. Upper extremity injuries are frequently encountered. Interestingly, motocross riders present with a significantly stronger left arm, even if the left hand is not dominant. This difference is attributed to the use of the clutch lever with the left hand, which is more frequent in motocross than in Enduro or desert rally. The wrist has been reported to be involved especially among motocross racers in contrast to road racing. Besides wrist fractures, scaphoid fractures have been previously without a detailed analysis of the injury mechanism. We report on three patients suffering scaphoid fractures caused by extreme hyperextension of the wrist during landing after a motocross jump. Two patients presented late three months following the initial trauma (both Herbert type C fractures), while one motocross athlete with a B 2-type scaphoid fracture was admitted to wrist surgery within a week. The B 2-type fracture was treated with open reduction and Herbert-screw fixation, while the C-type fractures were treated by Herbert-screw fixation in addition to a cortico-cancellous bone graft. Within ten weeks after the surgery the patients were back in sport at their given preoperative level. Hyperextension rather than wrist flexion appears as the predominant mechanism of wrist injuries in motocross riders. A more axial impact on the wrist is more likely to produce a radial fracture during the landing phase. Preventive strategies are internal muscular wrist stabilisation using eccentric training and external stabilisation by rigid gloves allowing only limited hyperextension.