The purpose of this study is to compare the efficacy of closed reduction with anesthesia and no anesthesia for developmental dislocation of the hip < 6 months

We treated children (<6 months) with prolonged traction before an attempted closed reduction. And compare the efficacy of closed reduction with anesthesia and no anesthesia for developmental dislocation of the hip. All the patients were followed up for a minimum of 18 months in order to identify any avascular changes in the femoral head. The presence of avascular necrosis was assessed by the criteria of Salter.

Inclusion Criteria:

• The patients with GrafⅢ/Ⅳtype DDH diagnosed by ultrasound or if they were IHDI (International Hip Dysplasia Institute) grade III or IV on radiographs，and The infants who were <6 months of age. Patients were followed for at least 18 months,by which time they had either completed treatment with no evidence of requiring further treatment or were treated surgically after failing brace treatment.

Exclusion Criteria:

• Infants were excluded if they had multiple congenital abnormalities, had prior treatment in other centres, or showed teratological dislocations. The last were defined as fixed dislocation of the hip in association with either a recognised syndrome or a neurological disorder.

developmental dislocation of the hip（ < 6 months）