Kinematic versus Mechanically Aligned Total Knee Arthroplasty: A Meta-Analysis of Randomized Controlled Trials.

Study Summary

21 randomized controlled trials undergoing primary total knee arthroplasty (TKA) for knee osteoarthritis were included in this systematic review and meta-analysis comparing kinematic alignment (KA) with mechanical alignment (MA). Pooled outcomes included pain, knee range of motion, walking distance, Knee Society Score (KSS) domains, Forgotten Joint Score (FJS), Oxford Knee Score (OKS), Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index, quality of life, hospital stay, and complications. KA produced statistically better resting pain, flexion, walking distance, joint awareness, function, satisfaction, and selected KSS, while most other outcomes and complication rates were comparable. However, most improvements were below established minimal clinically important difference thresholds, suggesting that KA is a safe alternative with modest rather than substantial clinical advantages.