Abstract
Classic essential tremor is a clinical syndrome of action tremor in the upper limbs (at least 95 % of patients) and less commonly the head, face/jaw, voice, tongue, trunk, and lower limbs, in the absence of other neurologic signs. However, the longstanding notion that essential tremor is a monosymptomatic tremor disorder is being challenged by a growing literature describing associated disturbances of tandem walking, personality, mood, hearing, and cognition. There is also epidemiologic, pathologic, and genetic evidence that essential tremor is pathophysiologically heterogeneous. Misdiagnosis of essential tremor is common because clinicians frequently overlook other neurologic signs and because action tremor in the hands is caused by many conditions, including dystonia, Parkinson disease, and drug-induced tremor. Thus, essential tremor is nothing more than a syndrome of idiopathic tremulousness, and the challenge for researchers and clinicians is to find specific etiologies of this syndrome.
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Acknowledgment
Supported by the Spastic Paralysis Research Foundation of Kiwanis International Illinois-Eastern Iowa District.
Conflict of Interest
Rodger J. Elble has received honoraria from Kinetics Foundation and Movement Disorder Society.
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Elble, R.J. What is Essential Tremor?. Curr Neurol Neurosci Rep 13, 353 (2013). https://doi.org/10.1007/s11910-013-0353-4
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DOI: https://doi.org/10.1007/s11910-013-0353-4
Keywords
- Essential tremor
- Physiologic tremor
- Dystonia
- Parkinson disease