Published: May 17, 2010
Updated: May 17, 2010
Essential tremor (ET) is a chronic condition characterized by involuntary, rhythmic trembling of a body part, most typically the hands and arms but may also affect the head, voice, and legs.
ET is considered the most common movement disorder and may affect as many as 10 million people in the United States. ET can occur at any age, but the usual age of onset is 45 or after. It may occur randomly or be inherited.
ET is usually associated with purposeful movement. It can be socially embarrassing and may cause difficulty in performing fine motor tasks such as writing, eating, and drinking. The tremor is usually absent or minimal with rest and disappears during sleep.
Although ET is a common movement disorder, it may be difficult to diagnose at times. ET is a clinical diagnosis; there is no definitive test. Evaluation of ET includes a thorough history and physical examination.
Surgery may be suggested to treat some patients with ET, particularly those who have not responded to conventional drug therapies. Surgical treatment involves thalamic deep brain stimulation and is usually reserved for patients with severe, disabling tremor and functional disability that interferes with the activities of daily living.