Dystonia refers to a clinical syndrome in which sustained involuntary muscle contractions result in twisting and repetitive movements, or abnormal postures. Secondary dystonia is associated with acquired or exogenous causes, hereditary neurologic syndrome Dystonia refers to a clinical syndrome in which sustained involuntary muscle contractions result in twisting and repetitive movements, or abnormal postures. Secondary dystonia is associated with acquired or exogenous causes, hereditary neurologic syndrome