Slijper Harm, Latash Mark L, Rao Noel, Aruin Alexander S
Department of Kinesiology, The Pennsylvania State University, University Park 16802, USA.
Clin Neurophysiol. 2002 May;113(5):642-55. doi: 10.1016/s1388-2457(02)00041-x.
To study adaptation of anticipatory postural adjustments (APAs) in paretic and non-paretic muscles of individuals with hemiparesis to changes in the direction of the self-initiated perturbation and additional manual support.
Electrical activity of leg and trunk muscles on both sides of the body and ground reaction forces were recorded in 10 patients with hemiparesis and a group of matched control subjects. Subjects released a standard load, held in the hand of the extended relatively unimpaired arm. The load was released either in front of the body or to the side, with or without the impaired arm touching an external stable surface.
APAs were reduced in individuals with hemiparesis, especially on the paretic side. In paretic muscles, the modulation of APAs with the direction of the perturbation was decreased or showed atypical patterns. Also the effects of touch were decreased in patients. Center of pressure displacements shortly after load release were similar in control subjects and patients.
The results suggest that the ability of individuals with hemiparesis to prepare for a self-initiated predictable perturbation is reduced and that they may use alternative strategies of postural stabilization.
研究偏瘫患者患侧和健侧肌肉的预期姿势调整（APA）对自我引发扰动方向变化及额外手动支撑的适应性。
记录10例偏瘫患者及一组匹配的对照受试者身体两侧腿部和躯干肌肉的电活动以及地面反作用力。受试者松开握在相对未受损伸展手臂手中的标准负载。负载在身体前方或一侧释放，同时患侧手臂接触或不接触外部稳定表面。
偏瘫患者的APA降低，尤其是在患侧。在患侧肌肉中，APA随扰动方向的调制作用减弱或呈现非典型模式。患者中触摸的影响也减弱。负载释放后不久，对照组受试者和患者的压力中心位移相似。
结果表明，偏瘫患者为自我引发的可预测扰动做准备的能力降低，并且他们可能采用替代的姿势稳定策略。
