title: Three-column classification and Schatzker classification: a three- and two-dimensional computed tomography characterisation and analysis of tibial plateau fractures.
abstract: OBJECTIVE
  The aim of the study was to evaluate inter-observer reliability and intra-observer reproducibility between the three-column classification and Schatzker classification systems using 2D and 3D CT models.
  
  
  METHODS
  Fifty-two consecutive patients with tibial plateau fractures were evaluated by five orthopaedic surgeons. All patients were classified into Schatzker and three-column classification systems using x-rays and 2D and 3D CT images. The inter-observer reliability was evaluated in the first round and the intra-observer reliability was determined during the second round 2 weeks later.
  
  
  RESULTS
  The average intra-observer reproducibility for the three-column classification was from substantial to excellent in all sub classifications, as compared with Schatzker classification. The inter-observer kappa values increased from substantial to excellent in three-column classification and to moderate in Schatzker classification The average values for three-column classification for all the categories are as follows: (I-III) k2D = 0.718, 95% CI 0.554-0.864, p < 0.0001 and average 3D = 0.874, 95% CI 0.754-0.890, p < 0.0001. For Schatzker classification system, the average values for all six categories are as follows: (I-VI) k2D = 0.536, 95% CI 0.365-0.685, p < 0.0001 and average k3D = 0.552 95% CI 0.405-0.700, p < 0.0001. The values are statistically significant.
  
  
  CONCLUSIONS
  Statistically significant inter-observer values in both rounds were noted with the three-column classification, making it statistically an excellent agreement. The intra-observer reproducibility for the three-column classification improved as compared with the Schatzker classification. The three-column classification seems to be an effective way to characterise and classify fractures of tibial plateau.
authors.affiliation: Department of Orthopaedics, University Hospital of Wales, 84 Colchester Avenue Penylan, Cardiff, UK, patangesubbarao@gmail.com.
authors.forename: Sheethal Prasad
authors.initials: SP
authors.lastname: Patange Subba Rao
authors.forename: James
authors.initials: J
authors.lastname: Lewis
authors.forename: Ziad
authors.initials: Z
authors.lastname: Haddad
authors.forename: Vishal
authors.initials: V
authors.lastname: Paringe
authors.forename: Khitish
authors.initials: K
authors.lastname: Mohanty
mesh_terms: D006801:Humans; D021621:Imaging, Three-Dimensional; D057072:Intra-Articular Fractures / Q000145:classification* / Q000000981:diagnostic imaging*; D015588:Observer Variation; D015203:Reproducibility of Results; D013978:Tibial Fractures / Q000145:classification* / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed