Tremors are involuntary shaking movements. Hands are commonly susceptible to tremors, which can make performing intricate or even everyday tasks difficult. There are three main types of tremor that can affect the hands. These tremors are classified by the circumstances under which the tremor occurs.
Kinetic Tremor
Kinetic tremors, also called intention tremors, affect the hands when a person is attempting to perform a task that involves movement, such as grasping, pulling, using a spoon to eat, or shaving. One way this type of tremor is diagnosed is by having the patient touch the tip of his finger to his nose. A kinetic tremor will make the hand involuntarily tremble while performing this task.
The most common cause of kinetic tremor is a progressive neurological disease called essential tremor. The Harvard School of Medicine Family Health Guide notes that almost 10 million people in the U.S. currently have this disease, and it often runs in families. The tremor may get worse over time, and is often exacerbated by caffeine and feelings of stress.
Static Tremor
A static tremor, also called a resting tremor, occurs when the muscles of the hands and arms are at rest. This type of tremor often dissipates as the patient moves his hands in a purposeful movement. The most recognized type of static tremor occurs in people with Parkinson's disease. A typical scenario for a person affected by Parkinson's is shaking of the hands when they are resting in their lap or on a table.
Postural Tremors
A postural tremor of the hands occurs when the arms and/or hands are held up against gravity. An example of a position that would trigger a postural tremor is a person holding her hands outstretched and parallel to the ground. Postural tremors tend to be seen with other types of tremors, depending on the cause. Cerebellar tremors, for example, often include postural, kinetic and static tremors. These are often caused by disease, overuse of some medications or chronic alcoholism. One side of the body is often more affected than the other.
