neurologic disorders
Tremor
Introduction
Tremors are involuntary, rhythmic, oscillatory movements of reciprocal, antagonistic muscle groups, typically involving the hands, head, face, vocal cords, trunk, or legs. Diagnosis is clinical. Treatment depends on the cause and type of tremor and may involve avoidance of triggers (physiologic),propranololorprimidone(essential), physical therapy (cerebellar),levodopa(parkinsonian), and possibly deep brain stimulation or thalamotomy (disabling and drug-refractory). (See also Overview of Movement and Cerebellar Disorders .) Tremor may be Normal (physiologic) Pathologic Physiologic tremor, usually barely perceptible, becomes noticeable in many people during physical or mental stress. Tremors vary in Pattern of occurrence (eg, intermittent, constant) Severity Acuity (eg, gradual, abrupt) The severity of tremor may not be related to the seriousness of the underlying disorder. For example, essential tremor is generally thought of as benign and should not shorten life, but symptoms can be disabling, and cerebellar degeneration has been detected in some neuropathologic studies. 