Rosenkranz K, Altenmüller E, Siggelkow S, Dengler R
Department of Neurology, Medical School Hannover, 30623, Hannover, Germany.
Clin Neurophysiol. 2000 Nov;111(11):2040-5. doi: 10.1016/s1388-2457(00)00460-0.
The influence of muscle vibration (MV) as a strong proprioceptive input on motorcortical excitability was studied in 5 patients with musician's cramp, 5 musician controls and 5 non-musician controls.
The relaxed flexor carpi radialis (FCR), involved in the dystonic movement in all patients, was vibrated using low frequency (80 Hz) and low amplitude (0.5 mm). Transcranial magnetic stimulation (TMS; intensity, 120% of motor threshold) was applied without MV, 3 and 9 s after the onset of MV. Motor-evoked potentials (MEPs) in the FCR and in the antagonistic extensor carpi radialis (ECR) were recorded.
With MV, musician and non-musician controls showed a facilitation of MEPs in the FCR and a decrease of MEPs in the ECR. In musician's cramp, both phenomena were significantly less pronounced.
The reduced facilitation of MEPs in musician's cramp indicates a reduced MV-induced activation of motorcortical areas representing the FCR. The less pronounced inhibition by MV reflects a reduced inhibitory control of the antagonistic ECR. As there were no differences between musician and non-musician controls, the observed changes in musician's cramp refer to this special form of focal dystonia. An impairment of focused motorcortical activation by proprioceptive input from a muscle involved in the dystonic movement is suggested.
研究肌肉振动（MV）作为一种强烈的本体感觉输入对5例音乐家性痉挛患者、5例音乐家对照和5例非音乐家对照的运动皮质兴奋性的影响。
对所有患者中参与肌张力障碍运动的放松桡侧腕屈肌（FCR）进行低频（80Hz）和低振幅（0.5mm）振动。在无MV时、MV开始后3秒和9秒施加经颅磁刺激（TMS；强度为运动阈值的120%）。记录FCR和拮抗肌桡侧腕伸肌（ECR）的运动诱发电位（MEP）。
在MV作用下，音乐家和非音乐家对照的FCR中MEP增强，ECR中MEP降低。在音乐家性痉挛中，这两种现象均明显不明显。
音乐家性痉挛中MEP促进作用减弱表明MV诱导的代表FCR的运动皮质区域激活减少。MV的抑制作用不明显反映了对拮抗肌ECR抑制控制的减弱。由于音乐家和非音乐家对照之间没有差异，音乐家性痉挛中观察到的变化与这种特殊形式的局灶性肌张力障碍有关。提示来自参与肌张力障碍运动的肌肉的本体感觉输入对聚焦运动皮质激活的损害。
