Greg Barlow1, Luke Donovan2, Joseph M Hart3, Jay Hertel4. 1. University of Virginia, 210 Emmet St. South, Charlottesville, VA 22904, USA. Electronic address: gbarlow39@gmail.com. 2. University of Virginia, 210 Emmet St. South, Charlottesville, VA 22904, USA. Electronic address: ltd2r@virginia.edu. 3. University of Virginia, 210 Emmet St. South, Charlottesville, VA 22904, USA. Electronic address: jmh3zf@virginia.edu. 4. University of Virginia, 210 Emmet St. South, Charlottesville, VA 22904, USA. Electronic address: jnh7g@virginia.edu.
Abstract
BACKGROUND:Lace-up ankle braces reduce the incidence of ankle sprains and have been hypothesized to do so through both mechanical and neuromuscular mechanisms. OBJECTIVE: To determine the effect of lace-up ankle braces on surface electromyography (sEMG) measures during walking in adults with chronic ankle instability (CAI). DESIGN: Randomized crossover. SETTING: Laboratory. PARTICIPANTS: Fifteen adults with CAI. MAIN OUTCOME MEASURES: Surface EMG activity was recorded from the anterior tibialis, peroneus longus, lateral gastrocnemius, rectus femoris, biceps femoris and gluteus medius during treadmill walking with and without lace-up ankle braces. The dependent variables were sEMG amplitude 100 ms pre- and 200 ms post-initial contact, time of activation relative to initial contact, and percent of activation across the stride cycle. RESULTS: When compared to no brace, ankle bracing resulted in lower pre-contact amplitude of the peroneus longus (p = 0.02). The anterior tibialis, peroneus longus, rectus femoris, and gluteus medius were activated later relative to initial contact (p < 0.03). The peroneus longus and rectus femoris were activated for a shorter percentage of the stride cycle (p < 0.05). CONCLUSION: Braces cause a change in neuromuscular activity during walking. Clinicians should be aware of these changes when prescribing braces, as it may relate to the mechanism in which braces decrease sprains.
RCT Entities:
BACKGROUND: Lace-up ankle braces reduce the incidence of ankle sprains and have been hypothesized to do so through both mechanical and neuromuscular mechanisms. OBJECTIVE: To determine the effect of lace-up ankle braces on surface electromyography (sEMG) measures during walking in adults with chronic ankle instability (CAI). DESIGN: Randomized crossover. SETTING: Laboratory. PARTICIPANTS: Fifteen adults with CAI. MAIN OUTCOME MEASURES: Surface EMG activity was recorded from the anterior tibialis, peroneus longus, lateral gastrocnemius, rectus femoris, biceps femoris and gluteus medius during treadmill walking with and without lace-up ankle braces. The dependent variables were sEMG amplitude 100 ms pre- and 200 ms post-initial contact, time of activation relative to initial contact, and percent of activation across the stride cycle. RESULTS: When compared to no brace, ankle bracing resulted in lower pre-contact amplitude of the peroneus longus (p = 0.02). The anterior tibialis, peroneus longus, rectus femoris, and gluteus medius were activated later relative to initial contact (p < 0.03). The peroneus longus and rectus femoris were activated for a shorter percentage of the stride cycle (p < 0.05). CONCLUSION: Braces cause a change in neuromuscular activity during walking. Clinicians should be aware of these changes when prescribing braces, as it may relate to the mechanism in which braces decrease sprains.
Authors: Mark A Feger; Shannon Snell; Geoffrey G Handsfield; Silvia S Blemker; Emily Wombacher; Rachel Fry; Joseph M Hart; Susan A Saliba; Joseph S Park; Jay Hertel Journal: Orthop J Sports Med Date: 2016-06-16