title: Analgesic effects of botulinum toxin A: a randomized, placebo-controlled clinical trial.
abstract: 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.
authors.affiliation: The Department of Orthopaedic Surgery, The Royal Children's Hospital, Parkville, Victoria, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Barwood
authors.forename: C
authors.initials: C
authors.lastname: Baillieu
authors.forename: R
authors.initials: R
authors.lastname: Boyd
authors.forename: K
authors.initials: K
authors.lastname: Brereton
authors.forename: J
authors.initials: J
authors.lastname: Low
authors.forename: G
authors.initials: G
authors.lastname: Nattrass
authors.forename: H K
authors.initials: HK
authors.lastname: Graham
mesh_terms: D019274:Botulinum Toxins, Type A / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D002547:Cerebral Palsy / Q000150:complications* / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D004311:Double-Blind Method; D005260:Female; D006617:Hip Dislocation / Q000209:etiology / Q000517:prevention & control* / Q000601:surgery*; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D018482:Muscle, Skeletal / Q000187:drug effects*; D009465:Neuromuscular Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D010149:Postoperative Pain / Q000503:physiopathology / Q000517:prevention & control*; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A