Characteristic Alterations in Responses to Imposed Wrist Displacements in Parkinsonian Rigidity and Dystonia Musculorum Deformans
Characteristic Alterations in Responses to Imposed Wrist Displacements in Parkinsonian Rigidity and Dystonia Musculorum Deformans
复制标题
帕金森病强直和肌张力障碍患者对手腕移位反应的特征性改变
DOI：
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
R. Blair
中科院分区：
文献类型：
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作者：
W. G. Tatton;W. Bedingham;Molly C. Verrier;R. Blair
摘要：对僵硬型帕金森病（PK）和变形性肌张力障碍（DMD）患者预先存在的背景活动水平进行了研究，研究了腕屈肌桡侧肌分段EMG活动的幅度和时间调制。诱发的M1和M2 - 3段的相互依赖性对预先存在的背景EMG活动和施加位移的初始速度建立以前的正常人群。21例帕金森病患者和12例肌张力障碍患者的个体反应与建立的正常“反应体积”进行了比较。刚性PK患者中M2 - 3段的增加幅度（与刚性测量相关）无法通过既存EMG活动的低水平来解释。因此，增加下行易化并不直接影响α运动神经元。缩短的肌肉中的异常兴奋和通过施加腕部伸展对拉伸的肌肉的强直性震颤的重置是另外两种被证明的异常，其也可能导致PK刚性。相比之下，DMD患者表现出正常的幅度调制的M1和M2 - 3段，但表现出正常的时间机制的干扰，导致恒定的持续时间的M1和M2 - 3响应与施加力阶跃负载。
ABSTRACT: The amplitude and temporal modulation of the segmented EMG activity in flexor carpi radialis, evoked by imposed angular wrist extension, was studied with respect to the level of pre-existing background activity in rigid parkinsonian (PK) and dystonia musculorum deformans (DMD) patients. The interdependence of the evoked M1 and M2-3 segments on pre-existing background EMG activity and initial velocity of imposed displacement was established previously for a normal population. Individual responses of 21 parkinsonian and 12 dystonic patients were compared to the established normal “response volume”. The augmented magnitude of the M2-3 segment in rigid PK patients, which correlates to the measure of rigidity, could not be accounted for by the low level of pre-existing EMG activity. Therefore, increased descending facilitation does not impinge directly on alpha motoneurons. Paradoxical excitation in the shortened muscle and resetting of tonic tremor of the stretched muscle by the imposed wrist extension are two other demonstrated abnormalities which may also contribute to PK rigidity. In contrast, DMD patients demonstrated normal amplitude modulation of the M1 and M2-3 segments, but exhibited a disturbance of normal temporal mechanisms that result in constant duration of the M1 and M2-3 responses with imposed force step loads.