The Evidence Base for Botulinum Toxin Injection for the Treatment of Cerebral Palsy–Related Spasticity in the Lower Limb: The Long-Term Effects

Botulinum toxin is a potent neurotoxin that is widely used (and has been for many years) for the treatment of focal spasticity. Its short-term effects have been well documented. There remains considerable ambivalence over its long-term effects, and some concern over side-effects. A scoping assessment of the literature defines the paucity of the evidence base concerning long-term effectiveness. Only three level 1 and two level 2 studies could be identified, on lower limb effects of botulinum toxin in children with cerebral palsy at a time interval greater than 1 year. Furthermore, our interpretation of the results of these studies is that there is no evidence of clinical benefit. We hope this analysis and summary can guide clinicians in counseling parents and patients as regards long-term expectations, and reservations/implications of management.