A 36-year-old male presents with new-onset tremors of the hands. He is a project manager at a small company, and the tremors intensify when he is working. He is a married father of one child, aged two years. He reports that his family life is stable, but that is not necessarily the case at his job.
There has been a great deal of turmoil and employee turnover recently at his company and working with new colleagues has made him self-conscious about his shaking hands. He notices that the tremors worsen when he is typing on the computer, using his cell phone, and eating or drinking at home or at work.
His past medical history is significant for an amblyopia ("lazy" eye) that was surgically corrected when he was 10 years old. He also had and an episode in which he passed out due to heat exhaustion during college football practice. He had a hospitalization for several days during which he fully recovered.
His grandmother (who is alive) has a shaky voice, but he does not recall any family members having a tremor.
The patient appears to be well nourished and slightly overweight but he is in no distress. His mental status examination is completely normal, and he does not have symptoms of anxiety or depression. He has normal respiratory sounds. His heart sounds are regular and his BPM is normal. He does not have abdominal distention, skin rashes, or lesions.
On neurological examination, the patient has normal muscle strength, sensation, reflexes, coordination, and gait. His vision is normal with his corrective lenses. During his motor strength examination, he exhibited a fine motor tremor of the left hand and slight shaking of his right hand.
Diagnosis: Essential tremor
According to the National Organization for Rare Disorders, symptoms of essential tremor (ET)—formerly known as benign essential tremor—causes a great deal of stress for patients. ET is characterized by repetitive fine-motor shaking that occurs with action but not at rest.
Symptoms typically occur in the upper and lower extremities, head, jaw, or mouth. Head tremors often manifest with a shaky sounding voice. The tremors often begin in the upper extremities and are usually asymmetric, involving one side of the body before the other, or involving one side to a greater degree than the other. Eventually, the tremors progress to involve both sides of the body, but they may remain asymmetric.
ET is a progressive and lifelong condition that worsens over time. Some patients may have more involvement of certain areas of the body for the duration of the condition. The tremors often worsen with movement of the affected area of the body. For some patients, anxiety can worsen the symptoms, although it is not a behavioral or psychological disorder. In advanced disease, the tremors may also occur at rest.
ET is believed to be hereditary. Several chromosomal abnormalities have been identified in association with the condition, but the chromosomal patterns are not consistent among different families.1 It is thought to be most likely inherited in an autosomal dominant pattern with variable penetrance.
Standard imaging studies used in clinical practice do not typically show brain abnormalities. Alterations have been seen on metabolic brain imaging studies in a research setting with changes noted in the associative motor areas, as well as inferior fronto-occipital and longitudinal fascicles, cingulum, anterior thalamic radiations, and uncinate fascicles.2
Continued: Treatment and take home points >
1. Hopfner F, Helmich RC. The etiology of essential tremor: Genes versus environment. Parkinsonism Relat Disord. 2018;46 Suppl 1:S92-S96.
2. Nestrasil I, Svatkova A, Rudser KD, et al. White matter measures correlate with essential tremor severity-A pilot diffusion tensor imaging study. Brain Behav. 2018;2:e01039.
3. Merchant SH, Kuo SH, Qiping Y, et al. Objective predictors of 'early tolerance' to ventral intermediate nucleus of thalamus deep brain stimulation in essential tremor patients. Clin Neurophysiol. 2018;129:1628-1633.