Management of the upper limb with botulinum toxin type A in children with spastic type cerebral palsy and acquired brain injury: clinical implications

Abstract

The aim of this article is to describe our clinical experience in treating muscle imbalance in 49 children with spastic upper extremity involvement. We discuss four cohorts of children treated with botulinum toxin type A (BTX-A), each with different treatment objectives. In the first group, 27 children were treated for functional improvement and, of these, 23 had a positive effect, while four had no objective benefit. In the second group, eight children were treated for purposes of presurgical planning; of these, four were referred for surgery, three continued with serial treatment and one child did not benefit from injection. The third group comprised six children who were treated to improve posture and care: in this group, four children demonstrated clear benefit and two children lost some function subsequent to injection. Finally, a fourth group of seven children were treated after acquired brain injury (three with severe tetraplegia, four with hemiplegia). In this group, all children experienced spasticity relaxation and two children with hemiplegia also gained functional benefit. In terms of adverse events, deterioration of upper extremity function was poorly tolerated but limited to the first 1--3 weeks postinjection. Grip strength or thumb grip were diminished if too high doses were used. Overall, our results with BTX-A were rewarding in children with no fixed contracture, good motor learning capacity and high motivation to train. Additionally, BTX-A treatment has proven valuable for counteracting spasticity in children with acquired brain injury. This treatment modality may not, however, be an appropriate treatment option for all children with severe upper extremity spasticity, due to the shorter duration of effect and the potential reduction in functional abilities seen in this cohort. In all cases, the selection of muscles to be treated needs careful clinical assessment. Dynamic EMG analysis should be performed whenever required to aid muscle selection, especially in children with spasticity combined with dystonia. Evaluation of M-responses suggests that for the forearm muscles, doses of BTX-A above 1.5 U/kg/muscle should not be used.