involuntary constant oscillating rhythmical movements in one or more parts of the body
produced by successive alternate contractions of opposing muscle groups
often reflect extrapyramidal or cerebellar disturbance

Classification (three clinically distinct forms):
• Action/intention tremor – appears or accentuated by voluntary movement of affected part – eg severe parkinsonism, severe essential tremor, cerebellar disease
• Rest/passive tremor – present when involved part is at rest – diminishes or disappears with active movement – eg Parkinsonism, anxiety, alcoholism, thyrotoxicosis, benign essential tremor, mercury poisoning
• Peduncular/red nuclear tremor – violent form of action tremor – usually in those with multiple sclerosis or midbrain CVA – may be present at rest – causes jerking extension movements of head

Comments are closed.