Changes in knee pain and walking speed following primary, unilateral total knee arthroplasty and their association: A systematic review and meta-analysis.

Objective: To quantify changes in knee pain and walking speed following primary, unilateral total knee arthroplasty (TKA) for knee osteoarthritis, and to examine their relationship during recovery. Walking speed is a key indicator of functional recovery and long-term health, but whether pain relief translates into improved mobility remains unclear. Design: A systematic review and meta-analysis was conducted following PRISMA guidelines. PubMed was searched to September 2025 for studies reporting pre- and post-TKA values of knee pain (WOMAC-pain or KOOS-pain) and self-selected walking speed in adults undergoing primary, unilateral TKA. Pooled changes were calculated using inverse-variance weighted random-effects models. Meta-regression explored associations between pain and walking speed, adjusting for covariates. Results: Eighteen studies (n ​= ​819; 64.1 ​% female; age 65.1 ​± ​8.3 years; body mass index 28.4 ​± ​5.9 ​kg/m2) were included. Knee pain significantly decreased by 27-36 points (WOMAC-pain) and 19-40 points (KOOS-pain), exceeding minimal clinically important differences. Walking speed increased by +0.12 ​m/s at 3 months and +0.18 ​m/s at 12 months, both exceeding the +0.1 ​m/s threshold for clinically relevant change. No significant change in speed occurred before 3 months, and a non-significant decline appeared beyond 12 months. Meta-regression revealed greater knee pain (β ​= ​-0.005, p ​< ​0.001) and use of WOMAC-pain (vs. KOOS-pain) (β ​= ​-0.224, p ​< ​0.001) predicted slower walking speed (R2 ​= ​0.48, p ​< ​0.001). Conclusions: TKA yields substantial pain relief and improved walking speeds by 3-12 months. However, mobility gains are not sustained beyond one year and are influenced by pain. Postoperative care should support both symptoms and mobility to improve long-term outcomes.