Preoperative Predictors Associated with Pain in the Contralateral Knee Joint after Unilateral Total Knee Arthroplasty

: [Purpose] The purpose of this study was to determine whether preoperative physical and psychological factors of patients are associated with postoperative contralateral knee joint pain after unilateral total knee arthroplasty (TKA). [Participants and Methods] The participants were 43 patients who underwent unilateral TKA. The study investigated the relationship between preoperative physical factors, quality of life rating scale, and psychological factors on the presence of postoperative contralateral knee pain. [Results] Pain at 3 months postoperatively was related to rumination on the Pain Catastrophizing Scale (PCS) and usual activities on the Japanese Knee Osteoarthritis Measure (JKOM). [Conclusion] The results suggest that preoperative PCS rumination and JKOM usual activities may be predictors of the presence of contralateral knee pain at 3 months postoperatively.