title: Earlier time to reduction did not reduce rates of femoral head osteonecrosis in pediatric hip fractures.
abstract: OBJECTIVE
  Hip fractures account for less than 1% of all pediatric fractures; however, femoral head osteonecrosis (ON) after this injury ranges from 0% to 92%. The aim of this investigation was to add our experience to the literature and identify factors that may increase or decrease the risk of ON in pediatric patients with hip fractures.
  
  
  METHODS
  Institutional review board-approved retrospective review.
  
  
  METHODS
  Pediatric level II trauma center.
  
  
  METHODS
  Two hundred fifty-five pediatric hip fracture cases were reviewed from 1983 to 2009. Children were excluded if they had metabolic bone disease, subtrochanteric or pathologic fractures, slipped capital femoral epiphysis, or less than 1 year follow-up. This left 43 patients with 44 fractures in the study.
  
  
  METHODS
  Standard fixation procedures.
  
  
  METHODS
  Factors that could influence ON were analyzed and included age, Delbet classification, displacement, time to reduction, reduction quality and type, and whether a decompression was performed. Fisher exact tests were used with P <0.05 considered statistically significant.
  
  
  RESULTS
  Of the 44 cases included in the study, 9 (20%) developed ON. Age ≥11 years was the only statistically significant independent predictor of ON (P = 0.04). The details of 3 unique cases are also presented.
  
  
  CONCLUSIONS
  The rate of ON in this case series was 20%. No ON occurred in any child <11 years old. We were unable to demonstrate that earlier time to reduction reduced the incidence of ON.
  
  
  METHODS
  Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: *Akron Children's Hospital, Center for Orthopedics and Sports Medicine, Akron, OH; and †Biostats, East Canton, OH.
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Riley
authors.forename: Melanie A
authors.initials: MA
authors.lastname: Morscher
authors.forename: M David
authors.initials: MD
authors.lastname: Gothard
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Riley
mesh_terms: D019644:Arthroplasty, Replacement, Hip; D002648:Child; D005260:Female; D005271:Femur Head Necrosis / Q000209:etiology / Q000517:prevention & control*; D006620:Hip Fractures / Q000150:complications / Q000601:surgery* / Q000628:therapy; D006801:Humans; D008297:Male; D019637:Orthopedic Procedures; D012189:Retrospective Studies; D013997:Time Factors