Neuromuscular Electrical Stimulation of Peroneal Longus on Balance Control Ability in Young Adults with Chronic Ankle Instability: A Randomized Controlled Trial

Objective This study aimed to investigate the effects of 6 wks of peroneal longus neuromuscular electrical stimulation on the balance control ability in young adults with chronic ankle instability. Design This study is a double-blind randomized controlled trial. Six weeks of neuromuscular electrical stimulation and placebo intervention were conducted in the neuromuscular electrical stimulation and control groups for 20 mins, three times a week, respectively. Thirty-eight participants successfully completed the whole intervention and single-leg standing tests. The kinetics data of the center of pressure trajectory during static single-leg stance were measured using a Kistler force platform. Two-way repeated measures analysis of variance was used to analyze the electrical stimulation effects. Results Significant interactions were detected in Cumberland Ankle Instability Tool scores and all balance parameters including displacement X, displacement Y, 95% confidence ellipse area, root-mean-square, and center of pressure mean displacement velocity ( P < 0.05, 0.103 ≤ η 2 ≤ 0.201). Significant between-group differences were found in Cumberland Ankle Instability Tool scores ( P = 0.003, Cohen’s d = 0.215), displacement X ( P = 0.045, Cohen’s d = 0.107), root-mean-square ml ( P = 0.019, Cohen’s d = 0.143), and 95% confidence ellipse area ( P = 0.031, Cohen’s d = 0.123) after the 6-wk interventions. Conclusions Six weeks of neuromuscular electrical stimulation on the peroneus longus can improve static balance control ability in young adults with chronic ankle instability, especially the stability of ankle frontal plane.