title: Inter- and intra-observer variation of the Schatzker and AO/OTA classifications of tibial plateau fractures and a proposal of a new classification system.
abstract: BACKGROUND
  The aim of this study was to evaluate the intra- and inter-observer variation of the Schatzker and AO/OTA classifications in assessing tibial plateau fractures, using plain radiographs.
  
  
  METHODS
  Fifty tibial plateau fractures were classified independently by six observers as per the Schatzker and AO/OTA classifications, using antero-posterior and lateral plain radiographs. Assessment was done on two occasions, 8 weeks apart.
  
  
  RESULTS
  We found that both the Schatzker and AO/OTA classifications have a high intra-observer (kappa = 0.57 and 0.53, respectively), and inter-observer (kappa = 0.41 and 0.43, respectively) variation. Classification of tibial plateau fractures into unicondylar versus bicondylar and pure splits versus articular depression +/- split conferred improved inter- and intra-observer variation.
  
  
  CONCLUSIONS
  The high inter-observer variation found for the Schatzker and AO/OTA classifications must be taken into consideration when these are used as a guidance of treatment and when used in evaluating patients' outcome. Simply classifying tibial plateau fractures into unicondylar versus bicondylar and pure splits versus articular depression +/- split may be more reliable.
authors.affiliation: Department of Orthopaedics and Trauma, Manchester Royal Infirmary, Manchester, UK. bcharalambos@hotmail.com
authors.forename: C P
authors.initials: CP
authors.lastname: Charalambous
authors.forename: M
authors.initials: M
authors.lastname: Tryfonidis
authors.forename: F
authors.initials: F
authors.lastname: Alvi
authors.forename: M
authors.initials: M
authors.lastname: Moran
authors.forename: C
authors.initials: C
authors.lastname: Fang
authors.forename: R
authors.initials: R
authors.lastname: Samarji
authors.forename: R
authors.initials: R
authors.lastname: Samaraji
authors.forename: P
authors.initials: P
authors.lastname: Hirst
mesh_terms: D006801:Humans; D015588:Observer Variation; D011859:Radiography; D013978:Tibial Fractures / Q000145:classification* / Q000000981:diagnostic imaging / Q000601:surgery