Effects of Vibro-Stimulation Ankle Bracing on Tactile Sensation and Center of Pressure Dynamics in Individuals with Chronic Ankle Instability: A Randomized Clinical Trial

Abstract

<bold>Background/Objectives:</bold> Chronic ankle instability (CAI) is a common sequela of lateral ankle sprain and is characterized by recurrent episodes of giving way, sensorimotor deficits, impaired postural control, and diminished functional performance. While exercise-based rehabilitation, including neuromuscular training and proprioceptive exercises, remains the gold standard for managing CAI, patients often require additional support during daily activities. Orthotic interventions predominantly address mechanical instability, yet there is a clinical gap in providing integrated solutions that simultaneously offer mechanical support and sensory feedback to enhance postural control. This study aimed to investigate the effects of a semi-rigid ankle brace combined with vibro-stimulation on tactile sensation and center of pressure excursion in individuals with CAI. <bold>Methods:</bold> A randomized clinical trial was designed with two parallel groups and repeated measurements over time. Thirty adults (n = 15 per group) aged 18-35 years, who met the International Ankle Consortium criteria for CAI, were recruited. Participants in the experimental group received a semi-rigid ankle brace integrated with a wearable vibro-stimulation system, whereas those in the comparison group used the ankle brace alone. Outcome measures were collected at baseline, after 10 min, and after 2 and 4 weeks. Primary outcomes included Vibration Detection Rate and phase plane portraits assessed using a 128 Hz tuning fork and a force plate. <bold>Results:</bold> The ankle bracing plus vibration band group demonstrated significantly greater improvement at 4 weeks than the orthosis group in Vibration Detection Rate (F (3,26) = 31.93, p < 0.001, eta(2) = 0.78). Also, the largest effect was observed for the anteroposterior phase plane portrait at 4 weeks (MD = -2.10 +/- 0.42, 95 CI: -2.96 to -1.23, p < 0.001, d = -1.79). <bold>Conclusions:</bold> The findings suggest that combining a semi-rigid ankle bracing with vibro-stimulation provides additional benefits over the use of bracing alone in individuals with CAI.