Tremor is an unintentional, rhythmic muscle movement involving to-and-fro movements (oscillations) of one or more parts of the body.

Most tremors occur in the hands.

Content 4

1. The cause of a tremor can be determined by its activation condition, topographic distribution, and frequency.1


Pivotal Assessment Finding

Activation Condition

01. Rest 02. Kineticr intention) Postural Isometric.


A sequential test for postural and kinetic tremors can be done by having the patient stretch his or her arms and hands out, followed by a simple finger-to-nose test.2,3 A rest tremor is virtually synonymous with parkinsonism, whereas an intention tremor often indicates a cerebellar lesion.1,10




Topographic Distribution

The topographic distribution of the tremor (e.g., limbs, head, voice) can also provide useful information. For example, a high-frequency tremor that involves the head is much more likely to be essential tremor than parkinsonian tremor.2,3 Several historical clues can play important roles in the differentiation of tremors. Tremor in older patients is more likely to be parkinsonian or essential tremor. Patients with sudden onset of tremor should be evaluated to determine if the tremor is caused by medications, toxins, a brain tumor, or a psychogenic cause. Patients with a gradual onset of tremor should prompt questions about Parkinson disease.


Frequency is generally classified as low (less than 4 Hz), medium (4 to 7 Hz), or high (more than 7 Hz).


In most cases, it is secondary to either essential tremor or Parkinson's disease. 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.



Pivotal Assessment Findings
History 01. Occurs at rest Chronic

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?



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