Correlations between commonly used clinical outcome scales and patient satisfaction after total knee arthroplasty.

UNLABELLED: Patient satisfaction is becoming increasingly important as a crucial outcome measure for total knee arthroplasty. We aimed to determine how well commonly used clinical outcome scales correlate with patient satisfaction after total knee arthroplasty. In particular, we sought to determine whether patient satisfaction correlates better with absolute postoperative scores or preoperative to 12-month postoperative changes. Patient satisfaction was evaluated using 4 grades (enthusiastic, satisfied, noncommittal, and disappointed) for 438 replaced knees that were followed for longer than 1 year. Outcomes scales used the American Knee Society, Western Ontario McMaster University Osteoarthritis Index scales, and Short Form-36 scores. Correlation analyses were performed to investigate the relation between patient satisfaction and the 2 different aspects of the outcome scales: postoperative scores evaluated at latest follow-ups and preoperative to postoperative changes. The Western Ontario McMaster University Osteoarthritis Index scales function score was most strongly correlated with satisfaction (correlation coefficient=0.45). Absolute postoperative scores were better correlated with satisfaction than the preoperative to postoperative changes for all scales. LEVEL OF EVIDENCE: Level IV (retrospective case series).