Pain Catastrophizing Improves After Total Knee Arthroplasty, but Still Has a Negative Effect on Outcomes in Japanese...

Preoperative pain catastrophizing has been reported to influence postoperative outcomes in total knee arthroplasty (TKA). However, little is known about how catastrophizing changes after surgery. This study assessed the longitudinal changes in pain catastrophizing following TKA and its clinical impact.

We included 267 patients who underwent TKA and assessed the Pain Catastrophizing Scale (PCS) preoperatively and at postoperative day seven, six weeks, six months, and one year. Patients undergoing bilateral TKA or contralateral knee surgery within one year before or after TKA were excluded. Outcomes included PCS, the 2011 Knee Society Score (KSS), and visual analog scale (VAS). Temporal changes were analyzed using linear mixed-effects models. There were two multivariable linear regression models constructed to evaluate concurrent associations and prospective predictors of 1-year KSS satisfaction.

In the mixed-effects model, PCS showed a modest, but statistically significant improvement from six weeks to six months, whereas VAS did not change significantly after six weeks. In the concurrent model, both the 1-year postoperative PCS (β = -0.390, P < 0.001) and VAS (β = -0.166, P = 0.021) were independently associated with the 1-year KSS satisfaction score. In the prospective model, the six months PCS (β = -0.241, P = 0.014) and VAS (β = -0.229, P = 0.018) independently predicted patient satisfaction at one year.

Pain catastrophizing improved after TKA, but remained independently associated with patient satisfaction at one year, even after adjustment for pain intensity. The PCS at six months was also associated with later satisfaction, suggesting that patient-perceived outcomes may reflect psychological dimensions beyond pain severity alone.