Botulinum toxin in the management of cerebral palsy

Over the past 5 years a number of studies of the use of Botulinum toxin A in the management of cerebral palsy have been conducted. Overall 105 children, with a mean age of 6 years, received BTX-A injections; there were no systemic side effects. Tone was reduced in 94% of muscles injected; this effect lasted from 6-26 weeks. Ankle kinematics showed improvement in dorsiflexion during gait with a concomitant decrease in maximal plantarflexion following calf BTX-A injection. In a randomized trial, BTX-A injection into calf muscles reduced equinus during gait for longer than standard casting, and was better tolerated. Initial experience with simultaneous calf and hamstrings injection showed significant beneficial changes in knee kinematics. However a double blind comparison of BTX-A and saline injected into the hamstrings revealed limitations to this single-level approach. Patients reported significant improvements following BTX-A injection into upper limbs, in comparison with saline, and limb stiffness as measured by resonant frequency was reduced. However there was no evidence of functional improvements in this double-blind trial. BTX-A has a role to play in the maintenance of the younger child with cerebral palsy until multi-level surgical intervention is appropriate.