Management strategy for prevention of avascular necrosis during treatment of congenital dislocation of the hip.

We retrospectively analyzed the cases of fifty children with unilateral congenital dislocation of the hip in an attempt to determine what factors in treatment were associated with the prevention of avascular necrosis of the femoral head. All children were less than thirty-six months old at the initiation of treatment, had no other anomalies, had their entire treatment rendered at the same institution, and were followed for at least one year after reduction. Avascular necrosis occurred in 36% of the patients; in all cases definite roentgenographic signs were apparent within twelve months of reduction. No patient whose hip had grown normally during the first twelve months after reduction later had avascular necrosis. The management strategy for congenital dislocation of the hip in the child who is less than thirty-six months old should include a minimum two-week period of traction until achievement of the +2 traction station and immobilization in the so-called human position following reduction. Skeletal traction, gradually increased over several weeks to an average of 39% of body weight, usually was required to attain the +2 station. Observation of these principles should decrease the incidence of avascular necrosis and increase the probability of obtaining a normal hip.