Preoperative Pain Catastrophizing Prior to Total Knee Arthroplasty is Associated With Worse Preoperative Symptoms and More Clinical Improvement: A Prospective Comparative Study

Background: Total knee arthroplasty (TKA) is a reliable procedure for end-stage osteoarthritis with excellent long-term survivorship, but approximately 15% of patients are not satisfied. Pain catastrophizing (PC) has been proposed as a potential cause but current evidence is limited to smaller studies with short-term follow-up. Our goal was to assess outcomes following TKA in a large cohort with and without PC. Methods: A prospective comparative study was performed with patients undergoing unilateral primary TKA between 2019 and 2021 with 2-year follow-up. All patients completed a PC Scale questionnaire preoperatively and a score of minimum 30 was considered PC. Outcomes consisted of Knee injury and Osteoarthritis Outcome Score-Physical Function Shortform (KOOS-PS), Oxford Knee Score (OKS), numeric rating scale Pain, and aseptic revisions. Ultimately, 301 patients were included (mean age 69 years [range, 30-92 years], with 60.8% women). Forty four patients (14.6%) had PC. Results: Preoperatively, PC patients had inferior KOOS-PS, inferior OKS, and more pain than non-PC patients (all P < .001). PC patients had more improvement from preoperatively to 6 months postoperatively for KOOS-PS, OKS, and pain (all P < .05) and to 12 months for KOOS-PS and OKS (both P < .005). Similarly, PC patients had more improvement from preoperative to 24 months for OKS (P = .003). At 24 months, however, PC patients reported more pain than non-PC patients. There was no difference in revision rates (P = .192). Conclusion: Patients who had PC reported worse function and pain preoperatively but had more improvement to 6 months and 12 months postoperatively. At 24 months, similar subjective function was noted, although PC patients reported more pain.