Post stroke hemi-dystonia in children: a neglected area of research

BACKGROUND Childhood arterial ischemic stroke (CAIS) is increasingly recognized as an important cause of significant long-term morbidity in the pediatric population. Post stroke movement disorders, above all hemi-dystonias, are much more common in children after stroke compared to adults. However, research in this field is largely lacking. By highlighting some important knowledge gaps, we aim to encourage future collaborative research projects in this particular field. FINDINGS Post stroke-dystonia seems to be much more common among children than adults. However, no reliable epidemiological data of post-stroke movement disorders in childhood are available, and differentiation between spasticity and dystonia can be challenging. Pharmacotherapy for dystonia is limited by lack of effect, especially in the long-term treatment. The pathophysiology of dystonia is complex and incompletely understood. Recent findings from functional imaging studies suggest that dystonia does not result from a single lesion but rather network dysfunctions and abnormalities in functional connectivity. However, very few patients with post stroke dystonia have been studied, and it is not clear to what extent pathophysiology of primary and post stroke ischemia shares common characteristics on network level. In general, progress in understanding the nature of childhood dystonia lags far behind adult onset CNS diseases. CONCLUSIONS Dystonia after CAIS is a common yet insufficiently understood and poorly studied clinical challenge. Studies to improve our understanding of the underlying pathophysiology and consequently the development of instruments for early prediction as well as targeted treatment of dystonia should become a high priority in collaborative childhood stroke research.