Assessment of Reproducibility of Sanders Classification for Calcaneal Fractures

OBJECTIVE : To assess intra- and interobserver reproducibility of Sanders Classification System of calcaneal fractures among experienced and less experienced observers. METHODS : Forty-six CT scans of intra-articular calcaneal fractures were reviewed. Four observers, two with ten years of experience in foot and ankle surgery and two third-year residents in Orthopedics and Traumatology classified the fractures on two separate occasions three weeks apart from each other. The intra and inter-observer reliability was analyzed using the Kappa index. RESULTS : There was good intraobserver reliability for the two experienced observers and one less experienced observer (Kappa values 0.640, 0.632 and 0.629, respectively). The interobserver reliability was fair between the experienced observers (Kappa = 0.289) and moderate among the less experienced observers (Kappa = 0.527). CONCLUSIONS : The Sanders Classification System showed good intraobserver reliability, but interobserver reproducibility below the ideal level, both among experienced and less experienced observers. Level of Evidence III, Diagnostic Studies.