Dystonic tremor refers to the presence of tremor in a body part which is also affected by dystonia. Dystonic tremor is usually irregular, focal, variable in amplitude, and relatively low in frequency (usually less than 7 Hz). When it affects the limbs, dystonic tremor is usually a postural and/or kinetic tremor which is usually absent at rest. A common example of dystonic tremor is the irregular and jerky head tremor which often accompanies cervical dystonia (see Chap. 40). The precise relationship of dystonic tremor to dystonia has been debated. Dystonic movements may be inherently tremulous in nature due to co-contraction of agonist and antagonist muscles.
KeywordsPublic Health Internal Medicine Body Part Movement Disorder Botulinum Toxin
Dystonic tremor.mp4 (19,808KB)
Clip 1: the patient exhibits a complex cervical dystonia producing left rotational torticollis, right laterocollis, and right shoulder elevation. The dystonic head posture is associated with mixed vertical (“yes-yes”) and horizontal (“no-no”) tremulous and jerky head movements. Clip 2: another patient displays a continuous jerky postural and rest tremor in right upper extremity in a variety of positions. The tremor appeared in early childhood on a background of perinatal distress and forceps delivery. Botulinum toxin has shown partial improvement in the tremor.