Hömberg V, Hefter H, Reiners K, Freund H J
J Neurol Neurosurg Psychiatry. 1987 May;50(5):568-79. doi: 10.1136/jnnp.50.5.568.
The effect of changes in mechanical limb properties on the peak frequency of different tremor forms was analysed. Wrist tremor was recorded by an accelerometer fixed to the dorsum of the hand and demodulated surface EMG was recorded from the wrist extensors, while the extended hand was loaded with successively heavier weights. Physiological tremor was characterised by flat EMG spectra and a gradual decrease in tremor peak frequency with increasing load, as would be expected from the properties of a passive spring-mass-system. Also the peak frequency of activated physiological tremor characterised by increased synchronisation between motor units decreased in frequency with increasing loads. EMG spectra showed clear peaks of activity at the various mechanically determined tremor frequencies. In contrast, in two pathological tremor forms, the postural tremor in Parkinsonian patients and essential tremor, peak frequency tended to remain stable irrespective of changes in load. The method therefore allows a simple distinction between physiological and these two pathological tremors.
分析了肢体机械特性变化对不同震颤形式的峰值频率的影响。通过固定在手背部的加速度计记录手腕震颤，并从腕伸肌记录解调后的表面肌电图，同时让伸展的手依次加载越来越重的重量。生理性震颤的特征是肌电图频谱平坦，且随着负荷增加震颤峰值频率逐渐降低，这与被动弹簧质量系统的特性预期一致。同样，以运动单位之间同步增加为特征的激活生理性震颤的峰值频率也随负荷增加而降低。肌电图频谱在各种机械确定的震颤频率处显示出明显的活动峰值。相比之下，在两种病理性震颤形式中，帕金森病患者的姿势性震颤和特发性震颤，无论负荷如何变化，峰值频率往往保持稳定。因此，该方法可以简单地区分生理性震颤和这两种病理性震颤。
