BOTULINUM TOXIN TYPE-A IN THE TREATMENT OF UPPER EXTREMITY SPASTICITY- A RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED TRIAL

Spasticity is a disorder of excess muscle tone associated with CNS dis ease. We hypothesized that botulinum toxin, a neuromuscular blocking a gent, would reduce tone in spastic muscles after stroke. This randomiz ed, double-blind, placebo-controlled, multicenter clinical trial evalu ated the safety and efficacy of botulinum toxin type A (BTXA) in the t reatment of chronic upper limb spasticity after stroke. Thirty-nine pa tients received IM injections of a total dose of either 75, 150, or 30 0 units of BTXA or placebo into the biceps, flexor carpi radialis, and flexor carpi ulnaris muscles. At baseline, patients demonstrated a me an wrist flexor tone of 2.9 and elbow flexor tone of 2.6 on the Ashwor th Scale (0 to 4). Treatment with the 300-unit BTXA dose resulted in a statistically and clinically significant mean decrease in wrist flexo r tone of 1.2 (p = 0.028), 1.1 (p = 0.044), and 1.2 (p = 0.026) points and elbow flexor tone of 1.2 (p = 0.024), 1.2 (p = 0.028), and 1.1 (p = 0.199) at weeks 2, 4, and 6 postinjection. In the placebo group, to ne reduction at the wrist was 0.3, 0.2, and 0.0 and at the elbow was 0 .3, 0.3, and 0.6 at weeks 2, 4, and 6 postinjection. BTXA groups repor ted significant improvement on the physician and patient Global Assess ment of Response to Treatment at weeks 4 and 6 postinjection. There we re no serious adverse effects. In this 3-month study, BTXA safely redu ced upper extremity muscle tone in patients with chronic spasticity af ter stroke.