title: Calcaneal Scoring as an Adjunct to Modified Oxford Hip Scores: Prediction of Contralateral Slipped Capital Femoral Epiphysis.
abstract: BACKGROUND
  In 2 recent studies, modified Oxford hip scores of 16 through 18 have been shown to predict an extremely high risk of contralateral slipping in unilateral slipped capital femoral epiphysis (SCFE). However, the modified Oxford system is not widely used. This may be due, in part, to the complexity of the scoring system, difficulty in viewing all 5 radiographic features on a single x-ray and phenotypic variation in the features. Ossification of the calcaneal apophysis provides an osteologic marker of skeletal maturation in relation to peak height velocity and has been described previously. We examine the value of the calcaneal apophyseal ossification sequence for predicting modified Oxford hip scores.
  
  
  METHODS
  We examined 279 pelvis and matching foot x-rays that were taken at the same session from 94 healthy children aged 3 to 18 years. A fellowship-trained pediatric orthopaedist determined the modified Oxford hip score for each hip radiograph. The calcaneal x-rays had been previously graded. Modified Oxford hip scores were compared with calcaneal scores for each set of matched hip and calcaneal x-rays.
  
  
  RESULTS
  Stage 0 to 2 calcanei had 94% of corresponding hip radiographs rated as modified Oxford scores of 16 to 18. Stage 3 calcanei had 54% rated as 16 to 18 and 31% rated as scores 19 to 21. Stage 4 calcanei had 31% rated as scores 19 to 21, and 68% rated as scores 22 to 26. Stage 5 calcanei had 100% rated as 22 to 26. Using data from Popejoy and colleagues' study, the weighted risk of contralateral SCFE was 94% for calcaneal stage 0, 86.5% for calcaneal stage 1, 90.3% for calcaneal stage 2, 55.8% for calcaneal stage 3, 6.1% for calcaneal stage 4, and 0 for calcaneal stage 5.
  
  
  CONCLUSIONS
  Calcaneal stages 0 to 3 correspond entirely to modified Oxford scores indicating elevated risk of contralateral SCFE. The calcaneal scoring system has potential for adjunctive use with the modified Oxford score for prediction of contralateral SCFE.
authors.affiliation: *Department of Orthopaedics and Rehabilitation, Yale School of Medicine, New Haven, CT †Department of Orthopaedics, University of Rochester School of Medicine, Rochester, NY ‡Department of Orthopaedics, Case Western Reserve University School of Medicine, Cleveland, OH.
authors.forename: Allen D
authors.initials: AD
authors.lastname: Nicholson
authors.forename: Coridon M
authors.initials: CM
authors.lastname: Huez
authors.forename: James O
authors.initials: JO
authors.lastname: Sanders
authors.forename: Raymond W
authors.initials: RW
authors.lastname: Liu
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Cooperman
mesh_terms: D000293:Adolescent; D000365:Age Determination by Skeleton; D015415:Biomarkers; D002111:Calcaneus / Q000000981:diagnostic imaging*; D002648:Child; D002675:Child, Preschool; D005260:Female; D064368:Healthy Volunteers; D006621:Hip Joint / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D010012:Osteogenesis; D060048:Slipped Capital Femoral Epiphyses
chemical_list: D015415:Biomarkers