Deuschl G, Köster B, Lücking C H, Scheidt C
Department of Neurology, University of Kiel, Germany.
Mov Disord. 1998 Mar;13(2):294-302. doi: 10.1002/mds.870130216.
Psychogenic tremor has become a rare movement disorder. Twenty-five patients from our movement disorder unit presented either with obviously nonorganic body shaking during stance or with extremity tremors. A sudden onset and a variable but rarely remitting course of the condition was common. The "coactivation sign of psychogenic tremor" and absent finger tremor were the most consistent criteria to separate them from organic tremors. Quantitative analysis of tremor shows decreasing amplitudes in most organic tremors when the extremity is loaded with additional weights. In contrast, we found an increase of tremor amplitude for most of the cases with psychogenic tremor. This might be caused by increased coactivation to maintain the oscillation. These clinical and electrophysiological features suggest a clonus mechanism induced by coactivation as the pathophysiological basis of psychogenic extremity tremor. Psychiatric evaluation did not show overt signs of hysteria for the majority of the patients. However, we found depression and functional somatic or psychosomatic conditions to be frequent among the patients. A reduced ability to cope with stressful situations may play a significant role. The clinical course of the condition is usually far from benign. We conclude that psychogenic tremor can be positively diagnosed by means of neurologic signs in the majority of patients and is not only a diagnosis of exclusion. The poor outcome makes early and serious neuropsychiatric attempts at therapy necessary.
心因性震颤已成为一种罕见的运动障碍。我们运动障碍科的25名患者表现为站立时明显的非器质性身体抖动或肢体震颤。病情突然发作且病程多变但很少缓解是常见的。“心因性震颤的共同激活征”和无手指震颤是将其与器质性震颤区分开来的最一致标准。震颤的定量分析显示，在大多数器质性震颤中，当肢体额外负重时，震颤幅度会减小。相比之下，我们发现大多数心因性震颤病例的震颤幅度会增加。这可能是由于共同激活增加以维持振荡所致。这些临床和电生理特征表明，由共同激活诱导的阵挛机制是心因性肢体震颤的病理生理基础。对大多数患者的精神科评估未显示明显的癔症迹象。然而，我们发现患者中抑郁症以及功能性躯体或身心疾病很常见。应对压力情况的能力下降可能起了重要作用。该疾病的临床病程通常远非良性。我们得出结论，在大多数患者中，心因性震颤可通过神经学体征得到肯定诊断，而不仅仅是排除性诊断。预后不佳使得早期进行认真的神经精神科治疗尝试很有必要。
