title: Lateral insertion is a good prognostic factor after in situ fixation in slipped capital femoral epiphysis.
abstract: BACKGROUND
  In situ fixation (ISF) is standard treatment for slipped capital femoral epiphysis (SCFE) to stabilize the epiphysis and to prevent further slip. The aim of this study was to clarify the incidence of slip progression after ISF and its prognostic factors.
  
  
  METHODS
  We retrospectively reviewed 53 hips in 49 consecutive SCFE patients who underwent single screw ISF and were followed until physeal closure. Clinical and radiographic findings were viewed to assess progression of the posterior tilting angle (PTA).
  
  
  RESULTS
  Mean PTA was 33.4 degrees (range, 18 to 75 degrees) at ISF and 35.9 degrees (range, 18 to 75 degrees) at physeal closure with progression of PTA of 2.5 degrees (range, -2 to 19 degrees). Slip progression occurred in 28 of 53 hips (53%), and more than five degrees of progression occurred in 14 hips (26%). Multiple regression analysis revealed that point of screw insertion (one point for lateral and two points for medial) was a significant prognostic factor for progression of the slip by the following formula: (progression of PTA) = -1.523 + 2.701 × (point of screw insertion), R(2) = 0.148, p = 0.005.
  
  
  CONCLUSIONS
  The current study showed that a screw inserted from the lateral side to the intertrochanteric line prevented postoperative slip progression.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Hagiwara
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba 260-8677, Japan. njonedr@chiba-u.jp.
authors.forename: Junichi
authors.initials: J
authors.lastname: Nakamura
authors.forename: Makoto
authors.initials: M
authors.lastname: Kamegaya
authors.forename: Takashi
authors.initials: T
authors.lastname: Saisu
authors.forename: Jun
authors.initials: J
authors.lastname: Kakizaki
authors.forename: Seiji
authors.initials: S
authors.lastname: Ohtori
authors.forename: Shunji
authors.initials: S
authors.lastname: Kishida
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Takahashi
mesh_terms: D002648:Child; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016268:Internal Fixators; D008297:Male; D011379:Prognosis; D011859:Radiography; D012189:Retrospective Studies; D060048:Slipped Capital Femoral Epiphyses / Q000000981:diagnostic imaging* / Q000601:surgery*