Eight children had valgus deformity of the ankle, resulting from fibular pseudarthroses and treated by bone-grafting. It was found that, in the growing child, bridging of the defect of the fibula resulted in correction of the valgus deformity as the fibula grew. The mechanism of production of the lateral malleolar elevation and of the valgus deformity of the ankle was removal of the thrust of growth contributed by the proximal epiphysis of the fibula.