Altered Spatiotemporal Muscle Synergies in Chronic Ankle Instability: Evidence of Proximal Compensatory Strategies During Landing

Abstract

Human locomotion relies on muscle synergies—modular strategies of the central nervous system—yet prior studies on chronic ankle instability (CAI) have largely focused on isolated muscle activation. To elucidate muscle coordination dynamics, we analyzed synergy patterns during landing in 22 unilateral CAI patients and 22 healthy controls. Surface EMG signals from ten muscles were processed using a recursive second-order differential equation model and decomposed via non-negative matrix factorization (NNMF).

Human locomotion relies on muscle synergies—modular strategies of the central nervous system—yet prior studies on chronic ankle instability (CAI) have largely focused on isolated muscle activation. To elucidate muscle coordination dynamics, we analyzed synergy patterns during landing in 22 unilateral CAI patients and 22 healthy controls. Surface EMG signals from ten muscles were processed using a recursive second-order differential equation model and decomposed via non-negative matrix factorization (NNMF).