What Is a Resting Tremor?

Static tremor

Resting tremor

Static tremor

It is a rhythmic tremor caused by the alternating contraction of active and antagonist muscles. Frequent finger-pick-like movements are common, frequency 4 to 6 times per second, appearing at rest, aggravating during tension, reducing during voluntary exercise, and disappearing during sleep; also visible in the lower jaw , Lips and limbs are characteristic signs of Parkinson's disease.

Tremor is a common first symptom of Parkinson's disease, which occurs in about 75% of patients. Tremor is caused by the continuous rhythmic contraction and relaxation of the synergistic muscles and diaphragmatic muscles of the limbs. The tremor typical of Parkinson's disease is resting tremor, which occurs when the patient is at rest or when muscles relax throughout the body, and it is even more pronounced. The tremor frequency is 4 to 6 Hz. The tremor usually first appears on the distal end of one side of the upper limb. The typical manifestation is a "rubbing nine" tremor between the thumb and the flexed index finger. It affects the trunk, and extends from one upper limb to the ipsilateral lower limb and the contralateral upper and lower limbs. The lower jaw, lips, tongue and head are generally affected last. When both upper and lower limbs are involved; the amplitude of upper limb tremor is greater than that of lower limbs. Very few patients experience tremor only in the lower extremities.

Resting tremor is a kind of compound tremor, often accompanied by alternating pronation, supination, and flexion-extension movements, and it does not appear in one form alone, and is usually variable. In the early stage of onset, resting tremor is volatile, which is reduced or temporarily disappeared during voluntary movement, but then reappears after a few seconds; to the later stage, tremor persists during voluntary movement, and tremor worsens during emotional agitation, anxiety, or fatigue, but it becomes worse during sleep or Disappeared during anesthesia. At present, techniques such as electromyography and three-dimensional accelerometers can be used to observe the rhythm and frequency of tremors, but no technique can be used as an objective assessment standard for tremors.