Incobotulinum booster injections in patients with spasticity and dystonia after stroke

Background.– Previous results in patients injected with abobotulinum toxin A and onabotulinum toxin A have shown that injection intervals shorter than 2 months may increase the risk for neutralising antibody formation and treatment non-response. As a result, for the last 10 years, we have adopted longer intervals to treat patients with spasticity and/or dystonia secondary to stroke. It has been showed that incobotulinum toxin A does not induce neutralising antibodies. Observations.– Methods.– Ten patients with spasticity and/or dystonia due to stroke underwent a booster injection one month after the first injection. The clinical results were compared to those previously obtained in the same 10 patients using a single injection. Secondary dystonia was evaluated using the Unified Dystonia Rating Scale (UDRS), while spasticity was evaluated according to the Modified Ashworth Scale (MAS). Results.– They showed that the booster injection protocol induced an improvement in 8 subjects. In the remaining 2 subjects, we did not find any difference between the results obtained using the single and the booster injection protocols. Conclusions.– The use of a booster injection improve the clinical outcome in patients with spasticity and/or dystonia after stroke, allowing an optimal treatment of those muscles that poorly responded to the first injection.