Analgesic effects of botulinum toxin A: a randomized, placebo-controlled clinical trial

Dev Med Child Neurol. 2000 Feb;42(2):116-21. doi: 10.1017/s0012162200000220.


Postoperative pain in children with spastic cerebral palsy (CP) is often attributed to muscle spasm and is difficult to manage using opiates and benzodiazepines. Adductor-release surgery to treat or prevent hip dislocation in children with spastic CP is frequently performed and is often accompanied by severe postoperative pain and spasm. A double-blinded, randomized, placebo-controlled clinical trial of 16 patients (mean age 4.7 years) with a mainly spastic type of CP (either diplegic or quadriplegic in distribution) was used to test the hypothesis that a significant proportion of postoperative pain is secondary to muscle spasm and, therefore, might be reduced by a preoperative chemodenervation of the target surgical muscle by intramuscular injection of botulinum toxin A (BTX/A). Compared with the placebo, BTX/A was found to be associated with a reduction in mean pain scores of 74% (P<0.003), a reduction in mean analgesic requirements of approximately 50% (P<0.005), and a reduction in mean length of hospital admission of 33% (P<0.003). It was concluded that an important component of postoperative pain in the patient population is due to muscle spasm and this can be managed effectively by preoperative injection with BTX/A. These findings may have implications for the management of pain secondary to muscle spasm in other clinical settings.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Botulinum Toxins, Type A / administration & dosage
  • Botulinum Toxins, Type A / pharmacology
  • Botulinum Toxins, Type A / therapeutic use*
  • Cerebral Palsy / complications*
  • Cerebral Palsy / physiopathology
  • Child
  • Child, Preschool
  • Double-Blind Method
  • Female
  • Hip Dislocation / etiology
  • Hip Dislocation / prevention & control*
  • Hip Dislocation / surgery*
  • Humans
  • Male
  • Muscle Contraction / drug effects*
  • Muscle, Skeletal / drug effects*
  • Neuromuscular Agents / administration & dosage
  • Neuromuscular Agents / pharmacology
  • Neuromuscular Agents / therapeutic use*
  • Pain, Postoperative / physiopathology
  • Pain, Postoperative / prevention & control*
  • Treatment Outcome


  • Neuromuscular Agents
  • Botulinum Toxins, Type A