Background: Osteonecrosis (ON) of the femoral head is one of the main complications associated with treatment of developmental dysplasia of the hips (DDH). The reported rates of ON vary widely between 6% and 48%, suggesting varying factors in these studies influence the rate. Several studies suggest open reduction combined with femoral shortening provides protection against ON. However, it is unclear whether confounders such as failed Pavlik harness treatment, preliminary traction, closed versus open reduction, and redislocation influence the rate of ON.
Questions/purpose: We therefore asked whether open reduction with concomitant osteotomies without femoral shortening, redislocation, and secondary surgical procedures for residual acetabular dysplasia influenced the rate of ON.
Methods: We retrospectively reviewed 64 children (78 hips) hospitalized with developmental dislocation of the hip between January 1998 and February 2007. Patients younger than 12 months were treated with closed or open reduction. Open reduction combined with concomitant pelvic and femoral osteotomies was performed in patients past walking age. ON was diagnosed from radiographs obtained at last followup. We used logistic regression analysis to identify predictors for the development of ON. The minimum followup was 3.2 years (mean, 6.8 years; range, 3.2-11.5 years).
Results: The overall rate of ON was 40%. Patients who underwent open reduction combined with concomitant osteotomies, experienced redislocation, or required secondary reconstructive procedures after initial reduction were at higher risk for having ON develop.
Conclusions: We advocate early reduction of the dislocated hip in the first year of life to avoid the need for concomitant osteotomies combined with open reduction.