Abstract / Summary
ABSTRACT Purpose The purpose of this study was to investigate the association between preoperative central sensitization and postoperative patient-reported outcomes, including failure to achieve a patient-acceptable symptom state (PASS) for postoperative satisfaction and pain after primary total knee arthroplasty (TKA), and to identify an exploratory cutoff value for the Central Sensitization Inventory (CSI). Methods This retrospective cohort study included 138 patients who underwent primary TKA for osteoarthritis. Preoperative central sensitization was assessed using the CSI. Postoperative outcomes at 1 year were evaluated using the 2011 Knee Society Score (KSS) and the Knee injury and Osteoarthritis Outcome Score (KOOS) pain subscale. Failure to achieve PASS was defined as a KSS satisfaction score <22 or a KOOS pain score <84.5. Multivariable logistic regression and receiver operating characteristic (ROC) curve analyses were also performed. Results Patients with central sensitization (CSI ≥40) had significantly higher odds of failing to achieve PASS for postoperative satisfaction [adjusted odds ratio (OR), 4.79; 95% confidence interval (CI), 1.21–19.01; p = 0.026] and pain (adjusted odds ratio, 6.14; 95% CI, 1.29–29.21; p = 0.023). When CSI was analyzed as a continuous variable, each 1-point increase was associated with a 5.7% increase in the odds of postoperative dissatisfaction and a 7.5% increase in residual pain. ROC analysis identified an exploratory CSI cutoff value of 18 points associated with failure to achieve PASS for both outcomes, with an area under the curve of 0.651 (95% CI, 0.557–0.744) for postoperative satisfaction and 0.709 (95% CI, 0.623–0.795) for postoperative pain. Conclusions Preoperative central sensitization was independently associated with postoperative dissatisfaction and residual pain after TKA. An exploratory CSI cutoff value below the conventional diagnostic threshold may help identify patients at increased risk of poor postoperative outcomes; however, external validation is required before clinical implementation.