Levin M F
Centre de Recherche, Institut de Réadaptation de Montréal, Québec, Canada.
Brain. 1996 Feb;119 ( Pt 1):281-93. doi: 10.1093/brain/119.1.281.
Approaches to the rehabilitation of movement in spastic hemiparetic patients depend on knowledge of the underlying mechanisms of movement deficits. The goals of this study were to characterize end-point trajectories and interjoint coordination of arm pointing movements to different targets on a horizontal planar surface and to correlate disruptions in motor control in the affected arm of hemiparetic subjects with the level of spasticity and the degree of functional impairment measured clinically. Arm movements were studied in six normal and 10 hemiparetic subjects. Data from the affected arms of hemiparetic subjects were compared with those from their non-affected arms and to data from the arms of normal subjects. Subjects were seated in front of a horizontal surface adjusted to the height of the sternal notch with the trunk stabilized. They made planar arm reaching movements (20 and 40 cm) to four different targets located directly in front of them and in the ipsilateral and contralateral workspace. Kinematic data from the finger, wrist, elbow and shoulder were recorded with a three-dimensional optical tracking system. Results showed that movement amplitudes were lower and movement times were significantly prolonged in the affected arms. Although trajectories were marked by deviations from smooth straight lines and characterized by increased dispersion and segmentation, even those subjects with the most severe spasticity could reach into all parts of the workspace with both their affected and non-affected arms. This indicated that movement planning in terms of extrapersonal space was unaffected in these subjects. On the other hand, the interjoint coordination of movements made into or out of the typical extensor or flexor synergies was equally disrupted. These findings suggest a bi-level control organization of pointing movements in both normal and hemiparetic subjects: the level of trajectory planning in extrapersonal space and the level specifying interjoint coordination according to the trajectory plan. Deficits in motor performance in stroke patients may be associated with problems at the second control level. This implies some strategies for the rehabilitation of stroke patients with motor disorders. Treatment aimed at improving arm function should be oriented toward restoring the normal sensorimotor relationships between the joints. We also found that while clinical spasticity scores were correlated with some aspects of motor performance, they provided little information about the movement deficit itself.
痉挛性偏瘫患者运动功能康复的方法取决于对运动功能障碍潜在机制的了解。本研究的目的是描述在水平平面上指向不同目标的手臂动作的终点轨迹和关节间协调性，并将偏瘫患者患侧手臂的运动控制障碍与临床测量的痉挛程度和功能损害程度相关联。对6名正常受试者和10名偏瘫受试者的手臂运动进行了研究。将偏瘫受试者患侧手臂的数据与其非患侧手臂的数据以及正常受试者手臂的数据进行比较。受试者坐在一个高度调整到胸骨切迹的水平表面前，身体躯干保持稳定。他们进行平面手臂伸展动作（20厘米和40厘米），指向位于他们正前方以及同侧和对侧工作空间中的四个不同目标。使用三维光学跟踪系统记录手指、手腕、肘部和肩部的运动学数据。结果表明，患侧手臂的运动幅度较小，运动时间显著延长。尽管轨迹表现出偏离平滑直线的情况，其特点是离散度和分段性增加，但即使是痉挛最严重的受试者，其患侧和非患侧手臂都能伸展到工作空间的各个部位。这表明这些受试者在个人空间外的运动规划未受影响。另一方面，进入或脱离典型伸肌或屈肌协同运动的关节间协调性同样受到破坏。这些发现表明，正常和偏瘫受试者在指向动作中存在两级控制组织：个人空间外的轨迹规划水平以及根据轨迹计划指定关节间协调性的水平。中风患者运动表现的缺陷可能与第二级控制水平的问题有关。这意味着针对患有运动障碍的中风患者的一些康复策略。旨在改善手臂功能的治疗应着眼于恢复关节之间正常的感觉运动关系。我们还发现，虽然临床痉挛评分与运动表现的某些方面相关，但它们几乎没有提供关于运动缺陷本身的信息。
