Primary Orthostatic Tremor

Timothy C. Hain, MD
Last updated 1/19/2002

Primary orthostatic tremor (OT) consists of rhythmical muscle contractions causing discomfort or unsteadiness while standing. It was first described by Heilman in 1984. The tremor is typically 12 to 18 Hz, with partial or complete cessation while walking or sitting.

It is presently controversial whether OT is a variant of essential tremor or a diagnostic entity in its own right.

Diagnosis is usually obtained based on clinical evaluation combined with surface electromyogram (EMG). Misdiagnosis is common and many patients are initially thought to have a non-organic (psychogenic) balance disorder. Frequency domain analysis of surface EMG or sway traces can diagnose this condition (Yarrow et al, 2001).

According to Pradalier and associates(2002), clonzepam is the preferred treatment for orthostatic tremor. Other drugs that may be effective include primidone and gabapentin (Neurontin)

References

• Yarrow et al. Force platform recordings in the diagnosis of primary orthostatic tremor. Gait and Posture 13(2001), 27-34
• Pradalier A, Apartis E, Vincent D, Campinos C.Rev Med Interne 2002 Feb;23(2):193-7 Related Articles, Links [Primary orthostatic tremor] [Article in French]