Tremor-spectrum in spinocerebellar ataxia type 3

J Neurol. 2012 Nov;259(11):2460-70. doi: 10.1007/s00415-012-6531-5. Epub 2012 May 17.


Spinocerebellar ataxia type 3 (SCA3) can be present with a combination of cerebellar, neuropathic, pyramidal, or extrapyramidal symptoms. Tremor is a classical but not frequent manifestation of SCA3 and there is a lack of detailed knowledge regarding its origin. To study the clinical and electrophysiological characteristics of tremor in SCA3 patients, the authors conducted a case series of 72 SCA3 patients. Clinical characteristics of tremor and associated signs, response to treatments, follow-up, and genetic results were collected. Electrophysiological study including polymyographic recording was possible in 4/6 patients and DaTSCAN in 2/6. The authors also performed a systematic review of SCA3 cases with tremor (n = 36) reported previously in the literature. We identified two different tremor-types in 6/72 patients with SCA3 mutations, a "fast" (6.5-8 Hz) action, postural or tremor in orthostatism (initial symptom), which became slower over time with associated parkinsonism with a follow-up of 10 years and a "slow" rest, action and intention tremor (3-4 Hz) with distal and proximal component (including axial tremor in orthostatism). Total improvement of limbs and tremor in orthostatism was obtained with levodopa with occurrence of fluctuations/dyskinesia. Partial benefit was observed when additional signs were present (myoclunus/dystonia). The differences in tremor subtypes in SCA3 may be related to various combinations of mild to severe dysfunctions of the cerebello-thalamo-cortical loop and the nigro-striatal dopaminergic pathway.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't
  • Review
  • Systematic Review

MeSH terms

  • Adult
  • Aged
  • Electromyography / methods
  • Female
  • Follow-Up Studies
  • Humans
  • Machado-Joseph Disease / complications
  • Machado-Joseph Disease / diagnosis*
  • Machado-Joseph Disease / physiopathology*
  • Male
  • Middle Aged
  • Tremor / complications
  • Tremor / diagnosis*
  • Tremor / physiopathology*