Gait Biomechanics, Symmetry Restoration, and Functional Recovery Following Total Knee Arthroplasty: A Prospective...

Background/Objectives: Total knee arthroplasty (TKA) is the standard surgical treatment for end-stage knee osteoarthritis (KOA); however, restoration of normal gait biomechanics remains an important challenge. Objective assessment of gait recovery may provide valuable information beyond conventional clinical outcome measures. This study aimed to evaluate changes in spatiotemporal gait parameters, symmetry restoration, and functional recovery during the first year following primary TKA, and to identify predictors of postoperative gait performance. Methods: A prospective longitudinal cohort study was conducted in 150 patients undergoing primary unilateral TKA for end-stage KOA. Spatiotemporal gait parameters, symmetry-related variables, and functional outcomes were assessed preoperatively and at 3, 6, and 12 months postoperatively. Gait analysis included walking speed, step length, cadence, stance phase symmetry, symmetry index (SI), loading asymmetry, and single-limb support time. Functional evaluation included the Timed Up and Go (TUG) test, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Knee Society Score (KSS). Repeated-measures analysis of variance (ANOVA), Pearson correlation analysis, and multivariate linear regression were performed. Results: Significant improvements were observed in all gait and functional parameters throughout follow-up (all p < 0.001). Walking speed increased from 0.84 ± 0.16 m/s preoperatively to 1.21 ± 0.18 m/s at 12 months, while step length increased from 49.8 ± 7.4 cm to 64.0 ± 6.4 cm and cadence from 91 ± 10 to 108 ± 8 steps/min. SI improved from 73 ± 11% to 93 ± 6%, whereas loading asymmetry decreased from 18.2 ± 6.1% to 4.8 ± 2.3%. Walking speed demonstrated strong correlations with WOMAC score (r = -0.74, p < 0.001) and TUG performance (r = -0.79, p < 0.001). Multivariate regression analysis identified preoperative walking speed (β = 0.47, p < 0.001) as the strongest predictor of postoperative gait recovery, while age and body mass index (BMI) were significant negative predictors. Conclusions: Patients undergoing primary TKA demonstrated substantial improvements in gait biomechanics, symmetry restoration, and functional performance during the first postoperative year. Objective gait assessment was strongly associated with clinical outcomes and may facilitate identification of patients at risk of delayed recovery. Incorporating quantitative gait analysis into postoperative evaluation may support individualized rehabilitation strategies aimed at optimizing functional outcomes following TKA.