Does botulinum neurotoxin A make walking easier in children with cerebral palsy? A randomized clinical trial.

AIM: To assess the effect of single botulinum neurotoxin A (BoNT-A) injections into the calf muscles on the gross energy cost of walking in children with cerebral palsy (CP) and to evaluate the effect of BoNT-A on walking capacity, physical activity, perceived changes in mobility, and pain.

METHOD: This was an industry-independent, randomized, quadruple-blind, placebo-controlled, multicentre trial (ClinicalTrials.gov registration: NCT02546999). Sixty-one children (33 male, median age [range] = 8 years [4-16 years]) with spastic CP and classified in Gross Motor Function Classification System (GMFCS) levels I and II allocated to single injections of either BoNT-A or 0.9% saline into the calf muscles. The main outcome was gross energy cost (J/kg/m); secondary outcomes were walking capacity, habitual physical activity, perceived change in mobility tasks, and calf pain at baseline, 4 weeks (P1), 12 weeks (P2), and 24 weeks (P3) after the injection.

RESULTS

The mean change in energy cost did not differ significantly between groups at the primary time point P2 (-0.27 J/kg/m, 95% confidence interval - 0.91 to 0.36, p = 0.404), nor at P1 or P3. Regarding the secondary outcomes, there was some evidence of a larger reduction in pain intensity in the group given BoNT-A (p = 0.043).

INTERPRETATION: One treatment with BoNT-A was not superior to placebo in making walking easier in children with CP classified in GMFCS levels I and II, at least in the short term. BoNT-A may have a pain-reducing effect.