Abstract
Aims: This study assesses the reliability of a new classi-þcation system for the periprosthetic femoral fractures. Methods: Forty (40) radiographs were evaluated by 6 observers, 2 expert, 2 hip fellows and 2 higher trainees. Each observer read the radiographs on 2 separate occasions (four weeks interval between the two readings) and classiþed each case as to its type. Four fracture types are described in this classiþcation system (GS, GU, BS, BU), according to bone quality (Good or Bad) and prosthesis stability (Stable or Unstable). Anatomical location is independently considered (rule of thirds). Speciþc radiographic criteria have been employed to access bone quality and prosthesis stability. Reliability was assessed by an independent statistician looking at the intra-observer and inter-observer agreement and using the κ (Kappa) statistic. Results: All data collected were subject to analysis using Cohenñs weighted kappa statistic. Stats Direct version 1.9.1 to measure the level of agreement between two observers. The results of the intra observer reliability testing showed a mean kappa value of 0.57 with a standard error of 0.29. The overall mean for the inter-reliability was 0.57 with a standard error of 0.28. Conclusion: The results indicate nearly substantial intra and inter-observer agreement. We suggest that the proposed classiþcation system for periprosthetic femoral fractures is reliable.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
