Division of Physical Therapy, Department of Rehabilitation Medicine, Emory University, United States.
Division of Physical Therapy, Department of Rehabilitation Medicine, Emory University, United States.
Gait Posture. 2022 Jul;96:275-278. doi: 10.1016/j.gaitpost.2022.05.022. Epub 2022 May 21.
In individuals with post-stroke hemiparesis, reduced paretic leg propulsion, measured through anterior ground reaction forces (AGRF), is a common and functionally-relevant gait impairment. Deficits in other biomechanical variables such as plantarflexor moment, ankle power, and ankle excursion contribute to reduced propulsion. While reduction in the magnitude of propulsion post-stroke is well studied, here, our objective was to compare the timing of propulsion-related biomechanical variables.
Are there differences in the timing of propulsion and propulsion-related biomechanical variables between able-bodied individuals, the paretic leg, and non-paretic leg of post-stroke individuals?
Nine able-bodied and 13 post-stroke individuals completed a gait analysis session comprising treadmill walking trials at each participant's self-selected speed. Two planned independent sample t-tests were conducted to detect differences in the timing of dependent variables between the paretic versus non-paretic leg post-stroke and paretic leg versus the dominant leg of able-bodied individuals.
Post-stroke individuals demonstrated significantly earlier timing of peak AGRF of their paretic leg versus their non-paretic leg and able-bodied individuals. Post-stroke participants displayed earlier timing of peak power of their paretic leg versus their non-paretic leg and able-bodied individuals, and earlier timing of peak ankle moment of the paretic leg versus able-bodied. No significant differences were detected in the timing of peak ankle angle.
The earlier onset of peak AGRF, peak ankle power, and peak ankle moment may be an important, under-studied biomechanical factor underlying stroke gait impairments, and a potential therapeutic target for stroke gait retraining. Future investigations can explore the use of interventions such as gait biofeedback to normalize the timing of these peaks, thereby improving propulsion and walking function post-stroke.
在脑卒中后偏瘫患者中，通过前向地面反作用力（AGRF）测量到的患侧腿部推进力减小是一种常见且具有功能相关性的步态障碍。其他生物力学变量（如跖屈肌力矩、踝关节功率和踝关节活动度）的缺陷也会导致推进力减小。虽然脑卒中后推进力减小的幅度已经得到了充分研究，但在这里，我们的目的是比较与推进相关的生物力学变量的时间。
在健全个体、脑卒中个体的患侧腿和非患侧腿之间，推进相关的生物力学变量的时间是否存在差异？
9 名健全个体和 13 名脑卒中个体完成了一次步态分析测试，包括在每个参与者自选择的速度下进行跑步机行走试验。进行了两项计划的独立样本 t 检验，以检测脑卒中个体的患侧腿与非患侧腿之间以及健全个体的患侧腿与优势腿之间的依赖变量时间的差异。
脑卒中个体的患侧腿的 AGRF 峰值时间明显早于其非患侧腿和健全个体的 AGRF 峰值时间。脑卒中患者的患侧腿的功率峰值时间明显早于其非患侧腿和健全个体的功率峰值时间，以及患侧腿的踝关节力矩峰值时间明显早于健全个体的踝关节力矩峰值时间。在踝关节角度峰值时间方面未检测到显著差异。
AGRF、踝关节功率和踝关节力矩峰值时间的提前出现可能是脑卒中步态障碍的一个重要且研究不足的生物力学因素，也是脑卒中步态再训练的潜在治疗靶点。未来的研究可以探索使用步态生物反馈等干预措施来使这些峰值的时间正常化，从而改善脑卒中后的推进力和行走功能。
