Syringomyelia-Associated Dystonia: Case Series, Literature Review, and Novel Insights.

[BACKGROUND] Syringomyelia has previously been suggested as a potential trigger of secondary dystonia. However, a definite causal relationship between the conditions remains to be established. We describe 4 cases of syrinx-associated dystonia, review past literature on the subject, and propose novel pathophysiological insights into this association.

[METHODS] We reviewed demographic, clinical, and neuroradiological features in 4 cases of syrinx-associated dystonia. A retrospective review of previously published literature on the subject was also conducted.

[RESULTS] Patients with syrinx-associated dystonia were younger than those with primary dystonia. None had sensory gestes. Syringomyelia frequently involved the cervical cord. Arnold-Chiari type 1 malformation was a common finding. Some patients responded to botulinum toxin and syrinx decompression.

[CONCLUSION] Further work is needed to clearly establish the correlation between syringomyelia and dystonia. However, plausibly, syrinx-related disruption of the dystonia network (through alterations in sensory inputs, loss of inhibition and cerebellar abnormalities) could explain the association.