Tremor - American Family Physician

Postural tremor occurs when the affected body part maintains position against gravity (e.g., extending arms in front of body). Isometric tremor results from muscle contraction against stationary objects (e.g., squeezing the examiner’s fingers). Kinetic tremor, which occurs with voluntary movement, is either simple kinetic tremor or intention tremor. Simple kinetic tremor is associated with movement of extremities (e.g., pronationsupination or flexion-extension wrist movements). Intention tremor occurs during visually guided movement toward a target (e.g., finger-to-nose or finger-to-finger testing), with significant amplitude fluctuation on approaching the target (Table 1). Although this classification helps in determining cause, the presentation of tremor syndromes varies. Other aspects of the history and physical examination should be considered when evaluating patients with tremor.