PhD Program in Rehabilitation Sciences, College of Applied Health Sciences, University of Illinois at Chicago, IL, USA.
Department of Physical Therapy and School of Engineering, Grand Valley State University, Grand Rapids, MI, USA.
Hum Mov Sci. 2020 Feb;69:102559. doi: 10.1016/j.humov.2019.102559. Epub 2019 Dec 5.
Impairment of anticipatory postural adjustments (APAs) is an important source of postural instability in older adults and individuals with neurological disorders. The aim of the study was to investigate whether APAs could be improved in people with stroke as a result of targeted exercise involving their unaffected upper extremity. Nine individuals with stroke and five healthy control individuals participated in the laboratory tests before and after a single session of practice consisting of pushing a medicine ball attached to the ceiling and stopping the ball with their palm when it returns. The tests included self-initiated perturbations induced by fast, discrete shoulder flexion movements and external perturbations induced by a pendulum impact. Bilateral EMG activity of eight trunk and leg muscles was recorded and analyzed during the anticipatory phase of postural control. Significantly early APAs onsets (p < .05) were seen in trunk and leg muscles after a single session of practice as compared to pre-practice in both the groups and individuals with stroke improved their ability to generate APAs more than control group. While the improvement was more pronounced on the unaffected side of the body, enhanced APAs were recorded on the affected side as well. The observed practice-related earlier activations of muscles confirm a possibility of APA enhancement in individuals with stroke. The outcome provides a background for the development of balance rehabilitation protocols focused on improvement of anticipatory postural adjustments in individuals with neurological disorders.
姿势预位调整（APAs）的损伤是老年人和神经障碍患者姿势不稳定的一个重要来源。本研究的目的是探讨针对未受影响的上肢进行有针对性的锻炼是否可以改善中风患者的 APA。9 名中风患者和 5 名健康对照者在单次练习（包括将一个附在天花板上的药球推开，然后用手掌接住返回的球）前后进行了实验室测试。测试包括由快速、离散的肩部弯曲运动引起的自我引发的扰动和由摆锤冲击引起的外部扰动。在姿势控制的预期阶段，记录并分析了 8 个躯干和腿部肌肉的双侧肌电图活动。与练习前相比，练习后两组和中风患者的躯干和腿部肌肉的 APA 起始明显提前（p<.05），中风患者比对照组更能提高产生 APA 的能力。虽然身体未受影响的一侧的改善更为明显，但受影响的一侧也记录到了增强的 APA。观察到的与练习相关的肌肉更早激活证实了中风患者的 APA 增强的可能性。研究结果为以改善神经障碍患者的姿势预位调整为重点的平衡康复方案的发展提供了背景。
