OBJECTIVETo explore factors influencing acetabular development after closed reduction in developmental dislocation of the hip (DDH), to provide theoretical basis for improving the therapeutic effects of closed reduction treatment of DDH.

METHODSA total of 100 children with single side DDH who were treated by closed reduction from January 2002 to December 2005 were followed up, and the AI and AI (D/W) of dislocation hip were measured at the 12th month after reduction. Ten factors such as gender, side, age, AI and AI (D/W) of dislocation hip before reduction, degree of dislocation, the rate of width of femoral head, femoral neck anteversion of dislocation hip before reduction, h/b rate,cut off adductor and skeletal traction et al were taken as independent variable, AI and AI (D/W) at the 12th month after reduction were taken as dependent variable,then multiple linear stepwise regression analysis was used to screen the major influencing factors.

RESULTSAge, gender, degree of dislocation, h/b rate, the rate of width of femoral head and femoral neck anteversion exerted obviously influence on AI and AI (D/W),and then age,degree of dislocation and FNA had positive correlation with AI and negative correlation with AI (D/W); the rate of width of femoral head and h/b rate had negative correlation with AI and positive correlation with AI(D/W). The development of acetabular of female patients was faster than that of male patients.

CONCLUSIONAge, gender,degree of dislocation, concentric reduction or not, the development degree of femoral head before reduction and proximal femoral shape are the major factors influencing acetabular development.