Muscle coactivation in children with cerebral palsy: A narrative review

We reviewed the literature describing muscle group coactivation (CA) strategies in children with cerebral palsy (CP) versus children who are typically developing (TD). We evaluate CP effects on functional activity in upper extremities (UEs) and on gait in lower extremities (LEs). We used a comprehensive systematic search of seven databases to locate qualitative and quantitative studies published between 2009 and 2019. Our search yielded 1595 articles, from which we retrieved 22. We independently examined titles and abstracts based on inclusion criteria and selected eight for data synthesis. We measured methodological quality of selected studies using National Institutes of Health study quality assessment tools. The sample size of six experimental studies were, for UEs, CP, n = 46 and TD, n = 23; for LEs, CP, n = 33 and TD, n =30; one cross-sectional study, for UEs only, CP, n = 68; and one observational study, for LEs only, CP, n = 15 and TD, n = 16. All eight studies reflected fair to good study quality. We conclude that excessive CA of muscle groups is common in children with CP. Further studies are required to investigate effects of therapeutic strategies for breaking abnormal patterns of muscle CA in UEs during functional tasks and in LEs during gait.