Dystonia during hand activity in children with spastic unilateral cerebral palsy, an observational study

•Dystonia in the upper extremity is very common in spastic unilateral cerebral palsy.•Dystonia seems to develop at an older age than what is mostly seen for spasticity.•Dystonia during activity correlates to lower functioning.•Several stereotyped hand positions were identified in each child with dystonia.•Fisting of the hand in toddlers could be a sign of dystonia.