Background Gait asymmetry is a sensitive marker of age-related neuromuscular dysfunction, but its multidimensional profiles across frailty stages remain unclear. This study characterized spatiotemporal, kinematic, and kinetic gait asymmetry across frailty-status groups.Methods A total of 150 older adults (Non-frail = 49, Prefrail = 80, Frail = 21) underwent 3D gait analysis. Fifty-one gait asymmetry features spanning spatiotemporal parameters, joint kinematics, and kinetics were derived. Group differences were examined using Kruskal–Wallis tests and pairwise Mann–Whitney U tests with Benjamini–Hochberg false discovery rate (FDR) correction.Results Nine of 51 features showed at least one significant pairwise difference after within-feature FDR adjustment. Compared with non-frail participants, prefrail participants exhibited greater asymmetry in single-support time (p = 0.033) and stride length (p = 0.001). Frail participants showed greater asymmetry than non-frail participants in stride length (p = 0.020) , hip flexion (p = 0.025), knee flexion (p = 0.019), hip external rotation (p = 0.026), knee flexion moment (p = 0.027), and knee eccentric power (p = 0.040). Compared with prefrail participants, frail participants also demonstrated greater asymmetry in hip flexion, hip external rotation, knee flexion moment, and knee eccentric power.Conclusions Gait asymmetry differed across frailty-status groups. Prefrail participants mainly showed feature-level differences in spatiotemporal asymmetry, whereas frail participants showed additional feature-level differences involving hip/knee kinematic and knee kinetic asymmetry. These findings describe exploratory, domain-informed gait asymmetry patterns associated with frailty status. These cross-sectional associations require longitudinal validation before prognostic or clinical monitoring utility can be inferred.Trial registration: Chinese Clinical Trial Registry, ChiCTR2300073905.
Gao et al. (Tue,) studied this question.