Katherine Hadlandsmyth, M Bridget Zimmerman, Roohina Wajid, Kathleen A Sluka, Keela Herr, Charles R Clark, Nicolas O Noiseux, John J Callaghan, Barbara A Rakel

While the majority of patients undergoing Total Knee Arthroplasty report substantial improvement in pain and function, a significant subset experience persistent post-surgical pain and dysfunction. Better understanding of the longitudinal postoperative course is needed, including the association between patient status following physical rehabilitation at 6 weeks post-TKA, to six month outcomes. This study aims to described the postoperative course of TKA and examine variables associated with change in pain and functioning between 6 weeks and 6 months post-TKA. In this longitudinal study of 223 participants, assessments of analgesic intake, depression, anxiety, pain catastrophizing, dysfunction, resting and range of motion (ROM) pain, and pain sensitivity were completed at 6 weeks post-TKA. Analgesic intake, pain ratings and dysfunction data were also collected at 6 months post-TKA. Pain and dysfunction ratings were divided into none-mild and moderate-severe categories. Between 6 weeks and 6 months post-TKA, 75% of the sample stayed in the same pain category, 20% improved, and 5% worsened. In terms of functional changes between 6 weeks and 6 months, 65% of the sample stayed in the same functional category, while 31% improved, and 5% worsened. These findings demonstrate that the majority of patients' pain and functioning remains stable between 6 weeks and 6 months post-TKA. However, a notable subset continues to improve or worsen in pain and functioning and the current study identifies variables associated with these changes.