Rehabilitation Science Research Laboratory, Department of Physical Therapy, Creighton University, Omaha, NE 68178, USA.
Clin Neurophysiol. 2012 Apr;123(4):764-73. doi: 10.1016/j.clinph.2011.08.004. Epub 2011 Sep 3.
Quantify the effects of increased amplitude and rate of muscle stretch on parkinsonian rigidity.
Eighteen subjects with Parkinson's disease participated in this study. Subjects' tested hand was passively displaced through 60° and 90° ranges of wrist flexion and extension at velocities of 50°/s and 280°/s in both treated and untreated conditions. Joint angular position, resistance torque, and surface electromyography (EMG) of the wrist flexors and extensors were recorded. Rigidity was quantified by normalized work scores and normalized angular impulses for flexion and extension, separately. Reflex responses of stretched and shortened muscles were quantified by mean EMG and EMG ratio. A series of ANOVAs was performed to determine the effect of amplitude, velocity and medication on selected variables.
Both work scores and angular impulses revealed that the larger displacement amplitude and the higher velocity were associated with significantly greater rigidity, increased EMG ratio and mean EMG of stretched muscles. Dopaminergic medication was not associated with a reduction in rigidity.
Parkinsonian rigidity is modulated by the amplitude and rate of muscle stretch.
These findings shed light on the biomechanical underpinnings and physiological characteristics of rigidity and may inform clinical rigidity assessment in Parkinson's disease.
量化肌肉拉伸幅度和速率增加对帕金森僵直的影响。
18 名帕金森病患者参与了这项研究。在治疗和未治疗条件下，以 50°/s 和 280°/s 的速度，分别使受试者的受试手被动移动通过 60°和 90°的腕关节屈/伸范围。记录关节角位置、阻力扭矩和腕屈肌和伸肌的表面肌电图（EMG）。通过分别对屈肌和伸肌的归一化功评分和归一化角冲量来量化僵直程度。通过平均 EMG 和 EMG 比来量化拉伸和缩短肌肉的反射反应。进行了一系列方差分析，以确定幅度、速度和药物对选定变量的影响。
功评分和角冲量均表明，较大的位移幅度和较高的速度与显著更大的僵直、拉伸肌肉的 EMG 比和平均 EMG 增加有关。多巴胺能药物治疗与僵直程度降低无关。
帕金森僵直受肌肉拉伸幅度和速率的调节。
这些发现揭示了僵直的生物力学基础和生理学特征，可能为帕金森病的临床僵直评估提供信息。
