Movement disorders in multiple sclerosis.

Movement disorders constitute a subspecialty of neurology focusing on a variety of conditions characterized by hypokinetic, hyperkinetic, or abnormally coordinated movements including, among others, tremor, dystonia, parkinsonism, myoclonus, chorea, ballismus, tics, restless limbs, and ataxia. The term "movement disorders" may be used to refer to either abnormal movements or syndromes that cause these abnormal movements. The classification of movement disorders is based on phenomenology, individual syndromes, or etiology. This article reviews terminology used to describe movement disorders, discusses individual movement disorders and their occurrence in patients with multiple sclerosis, and reviews treatment options.