A 45-year-old man comes to your office for evaluation of tremor. He started to notice the tremor recently, when he began building model airplanes with his son and had difficulty doing the fine motor tasks required for this hobby. His son has been making jokes about the shaking to his mother, who was concerned about this new tremor and scheduled an appointment for her husband to see you.
- What additional questions should you ask to gather more details regarding his tremor?
- How do you classify tremors?
- What warning symptoms can help you determine if this is indicative of a concerning disease or something more benign?
- How do you determine the cause of his tremor through the history?
Tremor is the most common movement disorder of adult life.1 In most cases, it is secondary to either essential tremor or Parkinson's disease. Patients often seek medical attention due to concern about possible Parkinson's disease or another serious illness. The most common etiology is essential tremor, although there are many other causes of tremor in adults.
Although the physical examination is important in the evaluation of tremor, the history alone can provide the necessary clues to a correct diagnosis. The initial approach is to first determine whether it occurs primarily with rest, holding a posture, or action. This will narrow the differential diagnosis and allow for a more directed history. Although a few alarm symptoms indicate the need for urgent assessment of tremor, the evaluation usually occurs in the outpatient setting.
|Tremor||A rhythmic oscillation of antagonist groups of muscles, in either an alternating or synchronous fashion.|
|Action tremor||An oscillation that occurs or increases during voluntary movement, generally of midrange frequency (6–8 Hz). Also called kinetic tremor.|
|Postural tremor||An oscillation that occurs while maintaining a fixed posture against gravity or during other fixed postures (clenched fist, standing), generally at a higher frequency (8–14 Hz).|
|Rest tremor||An oscillation that occurs with the affected body part at rest, during no action (voluntary contraction of muscles) and without resisting gravity, generally at a lower frequency (3–6 Hz).|
|Intention tremor||A type of action tremor in which an oscillation occurs orthogonal to the direction of movement and increases in amplitude as the target is approached. Usually denotes disease of the cerebellum and/or its connections.|
|Physiologic tremor||Irregular oscillations of 8–10 Hz occurring during maintenance of a posture, which usually disappear when the eyes are closed or a gravity load is placed on the muscles. By definition, mild physiologic tremor may be a normal finding and is common in the general population.|
|Enhanced physiologic tremor||Physiologic tremor is increased in amplitude due to fatigue, sleep deprivation, treatment with certain drugs, some endocrine disorders, caffeine use, or stress.|
|Essential tremor||Isolated postural or action tremor involving the hands and sometimes the head and voice without other neurologic findings. Genetically determined with a positive ...|