Focal Hand Dystonia as a Sign of Demyelinating Attack in Multipl Sclerosis: 'Report of Three Cases’

Abstract

Although it is known that dystonia is a basal ganglia disease, dystonic symptoms have been observed in association with lesions of various sites located in sensory and motor pathways. We report three cases of paroxysmal focal hand dystonia, which may be due to the damage of the somatosensorial pathways in the cervical spinal cord. We suggest that the dystonia in our patients may be related to these active demyelinating cervical plaques. Two female and one male patients with definite relapsing remitting MS between the ages of 22 to 45 were admitted with serious disability while using their right hands. In all three cases abnormal posture in the right hand and involuntary sustained contractions together with minor choreiform movements of the fingers were observed. Cervical MRI showed contrast-enhancing demyelinating lesions at the level of C2-3 in all. In one of the patient’s cranial MRI revealed also two new contrast-enhancing plaques on the neighbourhood of right posterior lateral ventricle and parietal cortex. No new or enhancing lesion was detected in the basal ganglia; indicating that the cervical spinal cord lesions were responsible for hand dystonia. In one of the patients, the right median SEP response was absent in accordance with the clinical symptom. All three patients were treated with 1 gram intravenous methylprednisolone a day for 5-10 days. Approximately one month later clinical symptoms have been completely disappeared and control cervical MRI revealed resolution of the active lesions in all.