An exploratory study of functional brain activity associated with gross motor function improvement in children with unilateral cerebral palsy.

Purpose: Identify relations of gross motor function and primary motor cortex (M1) functional activity pre and post gross motor interventions for children with unilateral cerebral palsy (UCP).

Methods: Thirteen children with UCP completed a gross motor intervention. Pre/post-intervention functional MRI outcomes included the laterality index (LI), activation volume, and spatial overlap of M1 activation during active ankle dorsiflexion. Advanced gross motor function (Challenge) was assessed pre/post-intervention, and 2-6 months later. Bivariate correlations and linear regression assessed relations between neuroimaging and motor function.

Results: Mean pre-intervention M1 activity was contralateral during dominant (LI =  +0.85, SD 0.21) but variable during the affected (LI =  +0.43, SD 0.57) ankle dorsiflexion. Changes in motor function and neuroimaging outcomes were not significantly associated. However, smaller affected ankle activation and less spatial overlap between ankle activations pre-intervention predicted Challenge improvements post-intervention (adjusted R² = 0.74, p = .001.).

Conclusions: This exploratory study identified pre-intervention neuroimaging predictors of post-intervention improvements in advanced gross motor function.