Primary Writing Tremor
Primary writing tremor is a relatively selective task-specific and unilateral action tremor which occurs nearly exclusively during the act of writing. In most cases, writing is a specific provocative factor, while in others it is provoked by pronation of the forearm and may therefore appear during other tasks in which a similar forearm posture is adopted. Tasks in which tools are used are often affected but much less severely than writing. It appears to be relatively nonprogressive. It has been thought to be either a variant of essential tremor or a variant of writer’s cramp with prominent dystonic tremor. It is an alternating tremor with a usual frequency of 5–7 Hz.
KeywordsPublic Health Internal Medicine Botulinum Toxin Motor Task Essential Tremor
Primary writing tremor.mp4 (MP4 13,149KB)
Examination shows absence of tremor with arms extended or while drinking from a cup. Tremor appears immediately on beginning to write. The brief bursts of tremor which occur during writing are characteristic features of this disorder.