Neuromuscular electrical stimulation improves frontal ankle motor control in individuals with chronic ankle instability during drop-landing.

OBJECTIVE: This study investigated the effect of neuromuscular electrical stimulation (NMES) on the frontal ankle motor control in individuals with chronic ankle instability (CAI) during drop-landing.

DESIGN: This was a randomized, controlled, double-blind trial. Thirty-six individuals with CAI were randomly assigned to each group. Participants received 6-week NMES intervention and sham stimulation in the NMES and control groups, respectively. Data was collected at week0 and week6. A mixed-effects model and analysis of covariance were employed to investigate the between-group differences in continuous and discrete outcome variables at week6, with the outcome variables at week0 as covariates.

RESULTS: Compared to control group, NMES group exhibited a 2.66° (2.45, 2.86) reduction in frontal ankle inversion angle, a 47.41°/s (-16.05, -78.77) decrease in peak ankle inversion angular velocity, and a 0.43 Nm/kg (0.18, 0.68) increase in peak ankle eversion moment during drop-landing at week6.

CONCLUSION: Applying 6-week NMES to the fibularis longus resulted in decreased ankle inversion angle and ankle inversion angular velocity, and increased peak ankle eversion moment during drop-landing. Consequently, NMES could be considered an effective modality for individuals with CAI to enhance the frontal ankle movement patterns and overall ankle motor control.