Van Der Walt et al. A double-blind, randomized, controlled study of botulinum toxin type A in MS-related tremor. Neurology. 2012 Jul 3;79(1):92-9.
METHODS: Twenty-three patients with MS contributed data from 33 upper limbs to this study. Each limb was randomized in a crossover design to receive botulinum toxin type A or placebo at baseline and the reverse treatment at 12 weeks. The 3 main outcomes were the median changes in Bain tremor rating scores for tremor severity, writing, and drawing an Archimedes spiral from baseline to 6 and 12 weeks after treatment with botulinum toxin type A compared with those after treatment with saline placebo. An independent rater scored randomized video assessments performed every 6 weeks over 6 months.
RESULTS: There was a significant improvement after botulinum toxin compared with that after placebo treatment in the Bain score for tremor severity at 6 weeks (p = 0.0005) and 12 weeks (p = 0.0001), writing at 6 weeks (p = 0.0001) and 12 weeks (p = 0.0003), and Archimedes spiral drawing at 6 weeks (p = 0.0006) and 12 weeks (p = 0.0002). More patients developed weakness after botulinum toxin treatment (42.2%) than after placebo injection (6.1%; (p = 0.0005). Weakness was mild (just detectable) to moderate (still able to use limb) and resolved within 2 weeks.
CONCLUSIONS: Targeted botulinum toxin type A injections significantly improve arm tremor and tremor-related disability in patients with MS. Classification of evidence: This study provides Class III evidence that targeted injection of botulinum toxin type A is associated with significant improvement in MS-related upper limb tremor.
The conclusions say it all. BoTox inhibits nerve function and signalling and hence paralyses muscles for a period of time so this result could be expected. Search the blog for other uses in MS.This is good news as the treatment of tremor is a difficult task.