Avascular necrosis of the femoral head in childhood: the results of treatment with articulated distraction method.

The treatment of avascular necrosis of the femoral head in children is still being debated. We performed articulated distraction in 11 children with avascular necrosis of the femoral head between March 1994 and February 1997. The reasons for avascular necrosis were: Perthes disease in eight patients, fracture of the femoral neck in two, and complication arising because of treatment of developmental hip dysplasia in one. Mean age was 7.9 years. Fixator duration time was 3.5 months and mean follow-up was 32 months. At follow-up, the femoral head was spherical and congruent in four patients, aspherical and congruent in five, and aspherical and incongruent in two according to Stulberg's criteria. The aim of the articulated distraction method is to neutralize muscle and weight-bearing forces, to prevent stress fractures of subchondral immature bone, to encourage synovial circulation, and to promote creeping substitution.