[Long-term results of congenital dislocation of the hip treated with Pavlik harness].

We have studied congenital dislocation and subluxation of the hip reduced by Pavlik harness with long-term roentgenographic results and prognostic factors. Eighty dislocations and thirty-five subluxations were assessed by X-ray. Average age at final follow-up was 17 years (14 to 23 years). Anatomical healing (Group I of Severin's classification) was 61.2% in dislocation and 71.5% in subluxation. Avascular necrosis of the femoral head was 7.0% (8 hips) and deformity was mild. Acetabular dysplasia appeared to be an important factor in determining the prognosis. In cases with both satisfactory and unsatisfactory results, the acetabular development differed from that of the normal cases from early childhood. After 11-12 year old the acetabular development normalized in cases with satisfactory results but did not in those with unsatisfactory results. Factors influencing the results were not clarified, there was the strong relationship between affected side and unaffected side in Center-Edge angle of Wiberg, Sharp's angle, AAQ (Approximate Acetabular Quotient) and Severin's classification respectively. This study concluded that long-term results of congenital dislocation and subluxation of the hip reduced by Pavlik harness were not always satisfactory and were strongly influenced by endogenous acetabular development in our cases.