Objective: To evaluate the potential for botulinum toxin (Dysport®) to improve the function of patients with dynamic equinus spasticity associated with cerebral palsy (CP).Patients and Methods:Ambulatory patients, aged 2–7 years, with a diagnosis of diplegic CP, without any evidence of fixed contracture, and with the potential to benefit from the injection of botulinum toxin to the gastrocnemius muscle were eligible. Videographic gait assessment (VGA) of initial foot contact, and the Gross Motor Function Measurement (GMFM) were performed at baseline. Patients were randomised to receive Dysport (30 units/kg) or placebo by intramuscular injection to the gastrocnemius muscle of both legs in a doubleblind manner. The GMFM and parental and investigator subjective functional assessments (SFA) were performed at weeks 4, 8 and 16 post-treatment. The VGA was repeated at weeks 4 and 16 only. Results: Fifty-two patients (26 Dysport, 26 placebo) were entered, only one patient from the placebo group discontinued during the follow-up. At week 4 initial foot contact had improved for 16/52 (31%) Dysporttreated patients compared with 13/50 (26%) placebo-treated patients, and had worsened for 4/52 (8%) Dysport-treated patients compared with 10/50 (20%) placebo-treated patients (p> 0.385). At week 16 initial foot contact had improved for 20/52 (38%). Dysport-treated patients compared with 10/50 (20%) placebo-treated patients, and it had worsened for 3/52 (6%) Dysport-treated patients compared with 12/50 (24%) placebo-treated patients (p> 0.004). GMFM scores demonstrated progressive improvement for both groups, but there were no statistically significant between-group differences. For the SFA at week 4 more Dysport patients demonstrated a good response (Parent 50%, Investigator 58%) compared with the placebo group (Parent 46%, Investigator 42%). At week 8 the proportion of patients demonstrating a good response was maintained in the Dysport group (Parent 58%, Investigator 54%), but had decreased in the placebo group (Parent 39%, Investigator 27%). At week 16 there was no obvious difference between groups.Despite the trend in favour ofDysport, there were no statistically significant between-group differences (p> 0.05) for the SFA. Dysport and placebo groups demonstrated similar adverse event profiles. Conclusion: Dysport (30 units/kg) substantially improves initial foot contact, and is a safe and effective treatment for dynamic equinus CP spasticity.

        Klíčová slova: cerebral palsy, spasticity, botulinum toxin, GMFM