Botulinum toxin a injections to the upper limbs in children with cerebral palsy: duration of effect.

We report our experience on the duration of effectiveness of botulinum toxin A injections to the upper extremities of children with cerebral palsy. A retrospective chart review was conducted on 30 consecutive patients (mean age, 9.9 ± 5.0 years) with spastic hemiparesis and quadriparesis. They received 1 to 5 treatments, totaling 56 treatments for the entire cohort. The injected muscles were the pronator teres (50/56), flexor carpi radialis (39/56), biceps (38/56), flexor carpi ulnaris (35/56), opponens (21/56), and adductor pollicis (17/56). Children were assessed for muscle tone and classified according to the Manual Ability Classification System before and after treatment. Functional improvement was apparent after 42 of 56 treatments, and muscle tone decreased significantly (P < .001). The mean duration of the effect was 7.0 ± 3.0 months. We conclude that the effect of botulinum toxin A to the upper limbs is retained for longer periods of time than those reported for lower limbs.