[Botulinum toxin in the management of spastic hip adductors in non-ambulatory cerebral palsy children].

PURPOSE OF THE STUDY: Spasticity of the hip adductors is a challenging problem for children with severe motor impairment due to cerebral palsy. It inhibits motor development and is also a risk factor for hip dislocation. Botulinum toxin has been found to be an effective means of treating spastic pes equinus in walking cerebral palsy patients and could have other indications. We conducted a prospective study to determine the functional and orthopedic contribution of botulinum toxin in the treatment of spastic hip adductors in non-ambulatory cerebral palsy children.

MATERIAL AND METHODS: The study included 11 quadriplegic children with cerebral palsy (mean age 5 years 9 months). Seven of the children had unilateral migration of the hip at study onset (> 40% radiographically). The children were given a single injection of botulinum toxin (Dysport: 20 units/kg/hip) in the adductor muscles (21 treated hips). The children were seen again at months 1, 3, 6 and 12 after treatment (with the exception of one patient not seen after the 6(th) month at the request of the parents). Spasticity was measured with the modified Ashworth scale. The motor level was determined with 8 position and motor items and with the GMFCS classification. Hip x-rays were obtained at study onset and once or twice during the follow-up.

RESULTS: There were no adverse effects of the treatment. Spasticity decreased by one point or more on the Ashworth scale in 20 hips at month 1 and remained low at month 3 in 14, and at month 6 in 12 of the 21 hips treated. The effect of the anti-spasticity treatment faded out from the 6(th) to the 12(th) month. Three children who experienced pain in the lower limbs were definitively relieved after treatment. Nine children achieved functional improvement (progress in at least one of the motor items). Three children were able to walk with a walker and two of them improved from level IV to level III on the GMFCS. The best functional responses appeared to occur in the younger children and in those who had good results at months 3 and 6. Among the 7 children whose hip was displaced by more than 40%, 5 had an unfavorable radiological progression and underwent surgery.

DISCUSSION: This study demonstrates that the botulinum toxin can be effective against spasticity of the hip adductors and that its effect is still significant 6 months after the injection in more than half the hips treated. It has an analgesic effect. This treatment has a functional impact even in children with severe motor impairment. The benefit has been modest but three children were able to progress to walking with a walker. The best functional results were observed in the younger children and in those whose spasticity had declined at month 3 and 6. It could thus be favored either by innate potential for motor development or by the treatment itself. The botulinum toxin did not improve the orthopedic prognosis of the children: 5 of the 7 with a risk of luxation worsened. Nevertheless, our study suggests that the botulinum toxin is a well-tolerated anti-spasticity treatment that is effective for the hip adductors providing an important contribution to the management of non-ambulatory cerebral palsy children.