Three column classification and Schatzker classification: a three and two dimentional computed tomography characterisation and analysis of tibial plateau fractures

Objective The aim of the study was to evaluate inter observer reliability and intra observer reproducibility between the three column classification using 3D CT reconstruction models and schatzker classification systems using 2D CT models. Materials and methods Fifty two consecutive patients with tibial plateau fractures were evaluated by two orthopaedic surgeons. All patients were classified into Schatzker and three column classification systems using CTimages. The Images were evaluated in a randomised and blind fashion. Demographics of the patient were blinded to reduce observer bias. The inter observer reliability was measured for both classfications in round one. In round two the process was repeated after two weeks and the intra observer reproducibility was measured using cohen kappa coefficient and level of agreement based on Landis and Koch. Results The average inter observer reliability for schatzker classification in round one were (k2D=0.661, 95% CI 0.531–0.697) in round two (k2D = 0.673, 95% CI 0.451–0.774). The three column classification average in round one were (k3D=0.851 95% CI 0.705–0.968), in round two (k3D=0.929 95% CI 0.813–1.00). The average intra observer reproducibility for Schatzker classification in round two for the first obsrever were (k2D=0.689 IQR, 0.6–0.846) for observer two (k2D=0.656 IQR 0.2988–1.0). The average intra observer reproducibility for three column for observer one were (k3D=0.693 IQR, 0.484-.859), for observer two (k3D=0.711 IQR, 0.5185–0.8294). 31 % of patients had a posterior column involvement. Conclusion 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 to the schatzker classification. The three column classification seems to be effective way to characterise and classify fractures of tibial plateau.