Medium-term response characterisation and risk factor analysis of botulinum toxin type A in the management of spasticity in children with cerebral palsy

We prospectively studied the medium-term effects of botulinum toxin type A (BTX-A) treatment in 197 children with cerebral palsy Between one and four target muscles were selected according to functional goals and biomechanical assessments, and were injected at multiple sites with BTX-A (BOTOX(R)). The mean total dose administered was 10.5 U BOTOX(R)/kg body weight. In 37% of treatment episodes, children were safely treated with high doses, 12-16 U/kg body weight. Significant improvements were seen in the Modified Ashworth and Tardieu scales at 3 and 12 weeks post-injection, and in muscle length, as determined by joint range of motion, at 3, 12 and 24 weeks post-treatment. Significant improvements in gait were noted using the Modified Physicians' Rating Scale, and joint kinematics and kinetics. Forty-five per cent of children were subsequently managed by repeated BTX-A, injections, 17% proceeded to single-level soft tissue surgery and 38% proceeded to multi-level surgery after mean intervals of 12.8, 16.4 and 17.3 months, respectively. Side effects were noted in 10 children (6.2% of total treatment occasions) and included local pain (1.2%), bruising (0.7%), temporary generalised weakness (0.3%), temporary incontinence (1.2%) and pneumonia (1.2%). In summary, BTX-A was safe and effective in the management of spasticity in children with cerebral palsy Side effects were infrequent, usually minor and self-limiting. Eur J Neurol 6 (suppl 4):S37-S45 (C) Lippincott Williams & Wilkins.