A double-blind placebo-controlled study of botulinum toxin in upper limb spasticity after stroke or head injury.

OBJECTIVE: To assess dose-response relationships to a single dose of botulinum toxin 'A' in upper limb spasticity associated with stroke or head injury.

DESIGN: A double-blind placebo-controlled randomized dose ranging study.

SETTING: A regional centre for neuroscience and a neurorehabilitation outpatient clinic.

SUBJECTS: Twenty-one hemiplegic patients with troublesome upper limb spasticity. Nineteen with stroke and two with head injury.

MAIN OUTCOME MEASURES: Spasticity (modified Ashworth), range of movement, posture (postural alignment and finger curl), disability (upper body dressing time and Frenchay Arm Test), patient-reported global assessment scale.

RESULTS: Combining data from all doses of botulinum toxin there was a significant reduction in spasticity at the wrist and fingers associated with a greater range of passive movement at the wrist and less finger curl at rest. There was a tendency for a further reduction in spasticity at elbow and wrist to occur with increasing dose but not for finger spasticity or curl. Effects present at six weeks were lost by 12 weeks except for a small improvement in elbow range of movement at the 1,500 Mu dose. There was no change in upper limb disability but a significant increase in patients' global assessment of benefit.

CONCLUSION: Botulinum toxin produced beneficial effects in spasticity and passive range of movement in the hemiplegic upper limb. Increasing the dose increased the magnitude of response for impairments in some muscle groups but had little effect on duration of response.