Premium
Orthostatic tremor: Clinical and electrophysiologic characteristics
Author(s) -
McManis Philip G.,
Sharbrough Frank W.
Publication year - 1993
Publication title -
muscle and nerve
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.025
H-Index - 145
eISSN - 1097-4598
pISSN - 0148-639X
DOI - 10.1002/mus.880161117
Subject(s) - physical medicine and rehabilitation , orthostatic vital signs , electromyography , medicine , sitting , essential tremor , neurological disorder , physical therapy , psychology , central nervous system disease , surgery , pathology , blood pressure
Orthostatic tremor, sometimes known as „shaky legs syndrome,” is a disorder of middle‐aged or elderly people characterized by feelings of unsteadiness in the legs and a fear of falling when standing. Patients stand on a wide base but walk normally. These symptoms are due to high‐frequency (13–18 Hz) burst firing in weight‐bearing muscles. They are attenuated by walking and are abolished immediately by sitting. Some authors believe that the disorder is a variant of essential tremor. This study reports the clinical and electrophysiologic features of orthostatic tremor in 30 patients. The findings indicate that orthostatic tremor is distinct from essential tremor, both clinically and electrophysiologically. The major differences are the frequency of electromyographic burst firing, the invariable involvement of lower limb and paraspinal muscles, and the task‐specific nature of the tremor in orthostatic tremor. The study shows that the diagnosis can be established rapidly with surface electromyographic recordings. © 1993 John Wiley & Sons, Inc.