Primary orthostatic tremor (POT) is a rapid 13–18 Hertz tremor that produces a subjective feeling of unsteadiness when standing, and is absent when seated or supine. It predominantly affects the legs during isometric contraction though a similar tremor can be seen in the arms and jaw. When present in the jaw this rapid tremor has been successfully treated with botulinum toxin. We sought to test whether symptoms of POT improved following injection of abobotulinumtoxinA to muscles in the legs. This randomised, double blind, placebo controlled cross-over design study enrolled eight patients with electrophysiologically confirmed POT. Each patient received injections of either 200 mU abobotulinumtoxinA or 0.9% saline in the tibialis anterior bilaterally, with cross-over after 20 weeks. Electrophysiological and clinical assessments were performed before and 6 weeks after each injection. Seven patients completed the study. No significant differences were seen in the primary outcome measures of time from standing to unsteadiness or symptom diary scores. Electrophysiological characteristics of POT remained remarkably constant throughout the study in all patients with variability of less than 1 Hertz in the frequency recorded. Falls were common, with one patient experiencing a fall with upper limb fracture whilst on the placebo. The frequency of falls correlated with both the severity of the self-rated symptoms and a shorter time to feeling unsteady with eyes closed. In conclusion, treatment with 200 mU of abobotulinumtoxinA in the tibialis anterior does not alter subjective experience of unsteadiness in POT. Postural instability and falls are common.
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- An unusual jaw tremor with characteristics of primary orthostatic tremor.Mov Disord. 1999; 14: 528-530
- Isolated high-frequency jaw tremor relieved by botulinum toxin injections.Mov Disord. 2006; 21: 1049-1050
- The Parkinson’s Disease Questionnaire (PDQ-39): development and validation of a Parkinson’s disease summary index score.Age Ageing. 1997; 26: 353-357
- Blinded placebo crossover study of gabapentin in primary orthostatic tremor.Mov Disord. 2006; 21: 900-905
- Orthostatic tremor: an association with essential tremor.Mov Disord. 1991; 6: 60-64
- The role and interaction of visual and auditory afferents in postural stability.Gait & posture. 2009; 30: 328-333
- Cerebellar neurocognition: insights into the bottom of the brain.Clin Neurol Neurosurg. 2008; 110: 763-773
Accepted: December 10, 2012
Received: October 24, 2012
© 2013 Elsevier Ltd. Published by Elsevier Inc. All rights reserved.