Four Cases of Orthostatic Tremor

J Korean Neurol Assoc > Volume 17(4); 1999 > Article

Journal of the Korean Neurological Association 1999;17(4): 574-578.

기립성 진전 4례

김대현, 김재우 ·이동국*

동아대학교 의과대학 신경과학교실,대구효성가톨릭대학교 의과대학 신경과학교실*

Four Cases of Orthostatic Tremor

Dae-Hyun Kim, M.D., Jae Woo Kim, M.D., Dong-Kuck Lee, M.D.*

Department of Neurology, Dong-A University College of Medicine , Department of Neurology, Taegu Hyosung Catholic University, School of Medicine*

Abstract

Orthostatic tremor (OT) is a rare movement disorder that consists of an involuntary shaking of the legs and trunk present only while standing. Although the origin and mechanism of this condition is not well understood, cases with symptomatic OT as well as primary OT have been described. We present the clinical features, EMG findings, and the responsiveness to drugs, of four cases with OT (3 primary and 1 symptomatic). Their symptoms were characterized by leg tremors that began immediately upon standing, lessened with rapid walking, and terminated when sitting or lying. Tremor in the legs interfered gait and sometimes was the cause for falling. Two of the cases had a familial history of essential tremors. There were no underlying causes in all the cases except for one who had hyperthyroidism. All the cases had postural tremor in both hands. Electromyography recordings from lower limb muscles revealed 13-18 Hz tremor in two cases and 4-5 Hz in one. Beta-adrenergic blockers had no effect on the tremor, but the responsiveness to clonazepam was excellent in one case and was modest in two cases. In the case with hyperthyroidism, OT completely disappeared with an antithyroid agent in three weeks. J Kor Neurol Ass 17(4):574~578, 1999 Key Words : Orthostatic Tremor, Essential Tremor, Hyperthyroidism