Efficacy of closed reduction for developmental dysplasia of the hip: midterm outcomes and risk factors associated with treatment failure and avascular necrosis

Background: The purpose of this study was to evaluate the efficacy after closed reduction (CR) in the treatment of developmental dysplasia of the hip (DDH) and investigate risk factors associated with CR failure and avascular necrosis (AVN) occurrence in the follow-ups.Primary and secondary outcome measures: The study retrospectively included 110 patients and 138 hips with DDH diagnosis between February 2012 and November 2015 in our single tertiary medical institution and underwent closed reduction. The failure rate of CR and the underlying risk factors were evaluated. meanwhile, the incidence of AVN and the related risk factors among the successful CR cases were assessed.Results: The overall failure rate of DDH treated by CR in present study was 31.16% (43/138). Risk factors for the CR failure was older age at the time of CR (≥18.35 month), large medical interval before CR (≥35.35 millimeters), and severer dislocation of the affected hip (IDHI grade III and IV). The incidence of AVN was 8.33% (6/72) in the patients with successful CR at last follow-up. No significant risk factors had been established in present study that associated with the AVN occurrence.Conclusions: For the treatment of DDH with CR, patients with younger age might achieve better outcomes, early diagnosis and early treatment might be the key point in the DDH treatment.