Copyright 981 by The Journal of Bone and Joint Surgery. Incorporated 140 ThE JOURNAL OF BONE AND JOINT SURGERY Management Strategy for Prevention of Avascular Necrosis during Treatment of Congenital Dislocation of the Hip

ABSTRACT: 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 avas-cular 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 per cent 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 ne-crosis. The management strategy for congenital disloca-tion 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 fol-lowing reduction. Skeletal traction, gradually in-creased over several weeks to an average of 39 per cent of body weight, usually was required to attain the +2 station. Observation of these principles should de-crease the incidence of avascular necrosis and increase the probability of obtaining a normal hip. Congenital dislocation of the hip is a complex or-thopaedic problem requiring sophisticated treatment. En-rors in management can result in a painful, unstable hip. Avascular necrosis of the femoral head, the most serious iatrogenic complication, occurs only following treat-ment4. Although some children with this complication may ultimately have a normal hip, many more will require subsequent reconstructive operations. This study seeks to identify the treatment options that affect the occurrence of avascular necrosis