Andreas Stotz1, Cornelius John2, Julian Gmachowski2, Anna Lina Rahlf2, Daniel Hamacher3, Karsten Hollander4, Astrid Zech2. 1. Department of Human Movement Science and Exercise Physiology, Institute of Sport Science, Friedrich Schiller University Jena, Seidelstraße 20, 07749, Jena, Germany. Electronic address: andreas.stotz@uni-jena.de. 2. Department of Human Movement Science and Exercise Physiology, Institute of Sport Science, Friedrich Schiller University Jena, Seidelstraße 20, 07749, Jena, Germany. 3. Methods and Statistics in Sports, Institute of Sport Science, Friedrich Schiller University Jena, Seidelstraße 20, 07749, Jena, Germany. 4. Institute of Interdisciplinary Exercise Science and Sports Medicine, MSH Medical School Hamburg, Am Kaiserkai 1, 20457, Hamburg, Germany; Department of Physical Medicine and Rehabilitation, Spaulding National Running Center, Harvard Medical School, 1575 Cambridge St., Cambridge, MA, 02138, USA.
Abstract
BACKGROUND: Individuals with chronic ankle instability (CAI) have an increased risk for recurrent injuries. The preventive effects of external ankle supports are not fully understood. This study aimed to examine the effect of elastic ankle support on running ankle kinematics. METHODS: 3D running gait analysis of individuals with and without CAI was conducted at three-minute-running trials at 2.78 m/s with and without elastic ankle support in a randomised order. Ankle kinematics and intra-individual standard deviations (variability) were calculated at each percent of the running gait cycle. Group and ankle support effects were calculated using statistical parameter mapping. RESULTS: Twenty-seven individuals were analysed (CAI: n = 14, controls: n = 13). When wearing ankle support, CAI individuals showed significantly decreased plantarflexion angles at 43-47 % (p = 0.033) and 49-51 % (p = 0.043) of the running gait cycle compared to normal running. In healthy controls, no differences in ankle angles between both conditions were found. Comparisons between CAI individuals and healthy controls showed statistically significant differences in the plantar-/dorsiflexion angles at 38-41 % (p = 0.044) with ankle support and at 34-46 % (p = 0.004) without ankle support. Significant ankle angle variability differences were found for ankle in-/eversion between CAI individuals and healthy controls (p = 0.041) at 32-33 % of the running gait cycle. CONCLUSIONS: Elastic ankle support reduces the range of sagittal plane running ankle kinematics of CAI individuals but not of healthy controls. Further research is needed to evaluate the association between ankle support effects and the risk for recurrent ankle sprains.
BACKGROUND: Individuals with chronic ankle instability (CAI) have an increased risk for recurrent injuries. The preventive effects of external ankle supports are not fully understood. This study aimed to examine the effect of elastic ankle support on running ankle kinematics. METHODS: 3D running gait analysis of individuals with and without CAI was conducted at three-minute-running trials at 2.78 m/s with and without elastic ankle support in a randomised order. Ankle kinematics and intra-individual standard deviations (variability) were calculated at each percent of the running gait cycle. Group and ankle support effects were calculated using statistical parameter mapping. RESULTS: Twenty-seven individuals were analysed (CAI: n = 14, controls: n = 13). When wearing ankle support, CAI individuals showed significantly decreased plantarflexion angles at 43-47 % (p = 0.033) and 49-51 % (p = 0.043) of the running gait cycle compared to normal running. In healthy controls, no differences in ankle angles between both conditions were found. Comparisons between CAI individuals and healthy controls showed statistically significant differences in the plantar-/dorsiflexion angles at 38-41 % (p = 0.044) with ankle support and at 34-46 % (p = 0.004) without ankle support. Significant ankle angle variability differences were found for ankle in-/eversion between CAI individuals and healthy controls (p = 0.041) at 32-33 % of the running gait cycle. CONCLUSIONS: Elastic ankle support reduces the range of sagittal plane running ankle kinematics of CAI individuals but not of healthy controls. Further research is needed to evaluate the association between ankle support effects and the risk for recurrent ankle sprains.