Clinical outcome scoring of intra-articular calcaneal fractures

Outcome reporting of intra-articular calcaneal fractures is inconsistent. This study aimed to identify the most cited outcome scores in the literature and to analyze their reliability and validity. A systematic literature search identified 34 different outcome scores. The most cited outcome score was the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot score, followed by the Maryland Foot Score (MFS) and the Creighton-Nebraska score (CN). Reliability (internal consistency) and validity (content, construct, and criterion) were determined for the 3 outcome scoring systems. Internal consistency (Cronbach's alpha, reliability) was similar for the Maryland Foot Score (alpha = 0.82) and American Orthopedic Foot and Ankle Society hindfoot score (alpha = 0.78), but lower for the Creighton-Nebraska (alpha = 0.61). Floor and ceiling effects were good for all 3 scores. The individual items within these outcome scores showing best content validity were pain, return to work, subtalar range of motion, walking distance, ankle range of motion, and gait abnormalities or limping. Construct validity was good for all individual items except sagittal motion, stability at physical exam, and shoe size. The 3 outcome scores showed high correlation with patient satisfaction as measured with a visual analog scale (VAS, criterion validity) and indication for an arthrodesis. In conclusion, pending consensus, we would recommend choosing between the widely accepted, reliable and valid AOFAS hindfoot and the Maryland Foot Score as the scoring systems of choice.