Orthostatic Tremor

Orthostatic tremor is a rare and enigmatic movement disorder characterized by rapid tremor of both legs and the trunk while standing, which disappears while the patient is either lying down or walking. It may be primary with or without postural arm tremor or associated with other neurological features, mainly parkinsonism (“orthostatic tremor plus”). Other clinical syndromes with tremor during standing have a lower frequency than 13 Hz and are labeled as slow orthostatic tremors or pseudo-orthostatic tremor. There are also some rare examples of secondary (symptomatic) orthostatic tremors associated with non-movement disorders. The pathogenesis of orthostatic tremor remains unclear. However, an accumulating body of evidence suggests a key role of the cerebellum in its pathophysiology; however, other brain regions such as the motor and sensory cortices and the thalamus may also be involved. Although a small number of medications (clonazepam, gabapentin, and dopaminergic drugs) can provide partial relief from tremor in a few patients, the pharmacological treatment is not optimal, and some patients with severe tremor may choose to undergo surgery.