title: Four Essential Tremor Cases with Moderately Impaired Gait: How Impaired can Gait be in this Disease?
abstract: BACKGROUND
  A body of literature is emerging regarding gait/balance impairments observed in essential tremor (ET) patients. Although impairment is generally mild, the full extent of the spectrum remains undefined. We present four ET cases with more severe gait/balance impairment.
  
  
  METHODS
  A BATTERY OF SUBJECTIVE AND OBJECTIVE GAIT/BALANCE ASSESSMENTS WAS PERFORMED: the Activities-specific Balance Confidence Scale, the Berg Balance Scale, and the Tinetti Performance Oriented Mobility Assessment (POMA). Tandem missteps during 10 steps were counted. Quantitative gait testing was performed (GAITRite) to quantify gait speed, dynamic balance, gait symmetry, and gait variability.
  
  
  RESULTS
  Two patients were middle-aged (38 and 52 years) and two were older (70 and 79 years). All had longstanding classic ET (duration 22-60 years). The mean POMA score was 21.5, which is indicative of moderate fall risk. On average, there were five missteps during tandem gait, which was higher than observed in substantially older ET cases (age 86.0±4.6 years), and four times higher than seen in ET patients of comparable age. On quantitative gait analysis, patients demonstrated significant balance impairment.
  
  
  CONCLUSIONS
  We present a sample of ET patients with a level of gait difficulty that would not be characterized as mild. The existence of such cases raises a number of questions, one of which is how impaired can gait be in ET?
authors.affiliation: GH Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, New York, United States of America ; Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, New York, United States of America ; Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York, United States of America ; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, College of Physicians and Surgeons, Columbia University, New York, New York, United States of America.
authors.forename: Elan D
authors.initials: ED
authors.lastname: Louis
authors.forename: Monica
authors.initials: M
authors.lastname: Galecki
authors.forename: Ashwini K
authors.initials: AK
authors.lastname: Rao
keywords: Essential tremor; ataxia; cerebellum; gait