Miéville Carole, Lauzière Séléna, Betschart Martina, Nadeau Sylvie, Duclos Cyril
Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal, CIUSSS Centre-Sud-de-l'Île-de-Montréal, Montreal, Canada; School of Rehabilitation, Université de Montréal, Montreal, Canada.
Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal, CIUSSS Centre-Sud-de-l'Île-de-Montréal, Montreal, Canada; School of Rehabilitation, Université de Montréal, Montreal, Canada.
J Electromyogr Kinesiol. 2018 Aug;41:41-49. doi: 10.1016/j.jelekin.2018.04.008. Epub 2018 Apr 24.
Spontaneous gait is often asymmetrical in individuals post-stroke, despite their ability to walk more symmetrically on demand. Given the sensorimotor deficits in the paretic limb, this asymmetrical gait may facilitate balance maintenance. We used a split-belt walking protocol to alter gait asymmetry and determine the effects on dynamic and postural balance. Twenty individuals post-stroke walked on a split-belt treadmill. In two separate periods, the effects of walking with the non-paretic leg, and then the paretic one, on the faster belt on spatio-temporal symmetry and balance were compared before and after these perturbation periods. Kinematic and kinetic data were collected using a motion analysis system and an instrumented treadmill to determine symmetry ratios of spatiotemporal parameters and dynamic and postural balance. Balance, quantified by the concepts of stabilizing and destabilizing forces, was compared before and after split-belt walking for subgroups of participants who improved and worsened their symmetry. The side on the slow belt during split-belt walking, but not the changes in asymmetry, affected balance. Difficulty in maintaining balance was higher during stance phase of the leg that was on the slow belt and lower on the contralateral side after split-belt walking, mostly because the center of pressure was closer (higher difficulty) or further (lower difficulty) from the limit of the base of support, respectively. Changes in spatiotemporal parameters may be sought without additional alteration of balance during gait post-stroke.
中风后的个体，其自发步态通常是不对称的，尽管他们能够根据要求更对称地行走。鉴于患侧肢体存在感觉运动缺陷，这种不对称步态可能有助于维持平衡。我们采用分带步行方案来改变步态不对称性，并确定其对动态平衡和姿势平衡的影响。20名中风后个体在分带跑步机上行走。在两个不同阶段，分别比较在扰动期前后，先让健侧腿、然后让患侧腿在较快传送带上行走，对时空对称性和平衡的影响。使用运动分析系统和装有仪器的跑步机收集运动学和动力学数据，以确定时空参数的对称比率以及动态平衡和姿势平衡。对于对称性得到改善和恶化的参与者亚组，比较分带步行前后通过稳定力和去稳定力概念量化的平衡情况。分带步行期间慢传送带上的那一侧，而非不对称性的变化，会影响平衡。分带步行后，在慢传送带上的腿的站立期维持平衡的难度较高，而对侧的难度较低，这主要是因为压力中心分别离支撑面边缘更近（难度较高）或更远（难度较低）。中风后步态期间，在不额外改变平衡的情况下，可能会寻求时空参数的变化。
