Summary

It was found that six months was needed to obtain improvement in physical function and quality of life.

Abstract

【Objective】
CR-type total knee arthroplasty (TKA) is expected to improve pain and ADL in a relatively short period of time. However, we sometimes hear patients express doubts and concerns about the duration of improvement in physical function after surgery. The aim of this study was to investigate the transition of improvement in physical function and quality of life from the early postoperative period.
【Methods】
A retrospective study of 222 knees (42 men and 180 women) undergoing TKA for knee osteoarthritis from January 2020 to December 2022 were evaluated up to 6 months after surgery. We compared between preoperatively , at discharge,3 months after surgery,　and 6 months after surgery. We investigated knee joint range of motion, the pain Visual Analogue Scale (VAS), the Knee Injury and Osteoarthritis Outcome Score (KOOS), the MOS Short-Form 36-Item Health Survey (SF-36), and the Timed Up and Go test (TUG).
【Results】
Compared to the preoperative period, significant improvements were observed at discharge in pain during exercise VAS, KOOS (symptoms, stiffness, pain), and knee joint extension angle (P<0.01). At 3 months postoperatively, significant improvement was observed in KOOS (sports), SF-36 (PF, RP, BP, GH, VT, MH), and TUG (P < 0.01). At 6 months postoperatively, significant improvement was observed in knee flexion angle and SF-36 (SF, RE) (P < 0.05). However, there were no significant differences in KOOS (ADL, QOL) at all time points.
【Conclusion】
This study revealed the following: knee joint extension angle, knee joint stiffness and pain, and basic activities such as walking and stair climbing could be improved at discharge. At 3 months postoperatively, SF-36 (PF, RP, BP, GH, VT, MH) and TUG improved significantly, indicating that 3 months is necessary for improvement in mental and physical QOL. Knee flexion angle, SF-36（SF, RE ）significantly improved at 6 months postoperatively, indicating that patients need about 6 months to return to social activities. It was found that six months was needed to obtain improvement in physical function and quality of life.