title: Does open reduction of the developmental dislocated hip increase the risk of osteonecrosis?
abstract: 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.
  
  
  OBJECTIVE
  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.
authors.affiliation: Pediatric Orthopaedic Department, Orthopaedic Hospital Vienna-Speising, Speisinger Strasse 109, 1130 Vienna, Austria. renata.pospischill@oss.at
authors.forename: Renata
authors.initials: R
authors.lastname: Pospischill
authors.forename: Julia
authors.initials: J
authors.lastname: Weninger
authors.forename: Rudolf
authors.initials: R
authors.lastname: Ganger
authors.forename: Johannes
authors.initials: J
authors.lastname: Altenhuber
authors.forename: Franz
authors.initials: F
authors.lastname: Grill
mesh_terms: D000704:Analysis of Variance; D001863:Bone Screws; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003131:Combined Modality Therapy; D005260:Female; D005271:Femur Head Necrosis / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000209:etiology*; D005500:Follow-Up Studies; D006618:Hip Dislocation, Congenital / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D015994:Incidence; D007223:Infant; D016015:Logistic Models; D008297:Male; D019637:Orthopedic Procedures / Q000009:adverse effects* / Q000379:methods; D010027:Osteotomy / Q000009:adverse effects / Q000379:methods; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000503:physiopathology; D011859:Radiography; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome