The lowest effective dose of botulinum A toxin in adult patients with upper limb spasticity

Objective: To define the lowest effective dose of botulinum toxin type A (Dysport®) and safety in the treatment of adult patients with upper limb spasticity.Design: This was a prospective, randomized, double-blind, dose-ranging study. Patients received either a placebo or one of three doses of Dysport® (350, 500, 1000 U) into five muscles of affected arm by anatomical and electromyography guidance. Efficacy was assessed periodically throughout the 6-month study period by the Modified Ashworth Scale (MAS), the Action Research Arm Test (ARA), the Barthel Index (BI) and the Visual Analogue Pain Scale (VAS).Results: Fifty patients were recruited. The four study groups were comparable at baseline with respect to their demographical characteristics and severity of spasticity. All doses of Dysport® studied showed a significant reduction from baseline of muscle tone and pain compared to placebo. However, the effect of functional disability was best at a dose of 500 U and the peak improvement was at week 8 after i...