The management of tremor.

The phenomenological classification of tremor is determined by finding out: c which parts of the patient’s body are affected by tremor? c what types (or components) of tremor, classified by state of activity, are present at those anatomical sites? The following definitions are used to describe the various tremor components evident on examination: c Rest tremor is a tremor present in a body part that is not voluntarily activated and is completely supported against gravity (ideally resting on a couch) c Action tremor is any tremor that is produced by voluntary contraction of a muscle. It includes postural, kinetic, intention, task specific, and isometric tremor: – Postural tremor is present while voluntarily maintaining a position against gravity – Kinetic tremor is tremor occurring during any voluntary movement. Simple kinetic tremor occurs during voluntary movements that are not target directed – Intention tremor or tremor during target directed movement is present when tremor amplitude increases during visually guided movements towards a target at the termination of that movement, when the possibility of position specific tremor or postural tremor produced at the beginning and end of a movement has been excluded – Task specific kinetic tremor—kinetic tremor may appear or become exacerbated during specific activities. Occupational tremors and primary writing tremor are examples of this – Isometric tremor—tremor occurring as a result of muscle contraction against a rigid stationary object.