Strength and coordination in the paretic leg of individuals following acute stroke
Strength and coordination in the paretic leg of individuals following acute stroke
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DOI：
10.1109/tnsre.2007.907689
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发表时间：
2007-12-01
影响因子：
4.9
通讯作者：
Federovich, Elissa H.
中科院分区：
文献类型：
--
作者：
Hidler, Joseph M.;Carroll, Marti;Federovich, Elissa H.
本研究的目的是确定急性中风幸存者是否表现出异常的协同模式在他们的影响下肢。在受试者站立时进行最大等距收缩时，测量膝关节和髋关节同时产生的关节扭矩，以及8块下肢肌肉的相关肌肉激活模式。10名急性中风幸存者和9名年龄匹配的对照组参加了这项研究。在所有关节测试中，中风受试者的最大等距扭矩明显低于年龄匹配的对照组受试者。然而，在不同方向上产生的协同力矩在两组之间没有显著差异。根据肌电图（electromyography， EMG）数据，我们发现中风受试者激活的拮抗肌群明显高于对照组受试者，这表明关节扭矩的缺陷可能至少部分归因于拮抗肌的共同收缩。我们的研究结果表明，急性偏瘫性卒中患者下肢运动障碍的主要原因是意志扭矩产生能力差，这至少部分归因于拮抗肌肉的共同收缩。此外，虽然我们没有观察到上肢常见的异常扭矩协同模式，但在许多测试方向上，肌肉激活模式在两组之间存在差异，这表明急性中风幸存者的运动控制策略发生了变化。
The goal of this study was to determine whether acute stroke survivors demonstrate abnormal synergy patterns in their affected lower extremity. During maximum isometric contractions with subjects in a standing position, joint torques generated simultaneously at the knee and hip were measured, along with associated muscle activation patterns in eight lower limb muscles. Ten acute stroke survivors and nine age-match controls participated in the study. For all joints tested, stroke subjects demonstrated significantly less maximum isometric torque than age-matched control subjects. However, the synergistic torques generated in directions different than the direction that was being maximized were not significantly different between the two groups. According to electromyography (EMG) data, it was found that stroke subjects activated antagonistic muscle groups significantly higher than the control group subjects, suggesting that deficits in joint torque may be at least partially attributable to co-contraction of antagonistic muscles. Our findings suggest that a primary contributor to lower limb motor impairment in acute hemiparetic stroke is poor volitional torque generating capacity, which is at least partially attributable to co-contraction of antagonistic muscles. Furthermore, while we did not observe abnormal torque synergy patterns commonly found in the upper limbs, muscle activation patterns differed between groups for many of the directions tested indicating changes in the motor control strategies of acute stroke survivors.