Dystonias

Dystonia is a hyperkinetic movement disorder with abnormal posturing and movements. Etiologies of dystonia include inherited and acquired causes. The first essential step for successful management of dystonia is to secure a correct diagnosis, excluding pseudodystonia (dystonic mimics) and “don’t miss” diagnoses. The latter category includes treatable disorders such as dopa-responsive dystonia and Wilson’s disease, among others. Symptomatic therapies are employed when etiology-specific therapies are not available or of incomplete benefit. Symptomatic therapy includes medications, botulinum toxin and surgery. Medications include cholinergic (anticholinergics), GABAergic (baclofen and clonazepam) and dopaminergic agents (levodopa and vesicular monoamine transporter 2 inhibitors). General principles of medical treatment of dystonia are to “start low, go slow,” hold the dose constant if side effects are mild, lower the dose if side effects are severe, consider combination therapy to avoid side effects at higher doses, and avoiding abrupt discontinuation of medications if they need to be stopped. Botulinum toxin injections, deep brain stimulation and other surgical techniques, as well as intrathecal and intraventricular baclofen are also employed when needed, and are discussed briefly in this chapter.