Detection of gait and postures using a miniaturized triaxial accelerometer-based system: accuracy in patients with mild to moderate Parkinson's disease

Arch Phys Med Rehabil. 2010 Aug;91(8):1272-7. doi: 10.1016/j.apmr.2010.05.004.


Objective: To examine whether gait and postures can accurately be detected with a single small body-fixed device in patients with mild to moderate Parkinson's disease (PD).

Design: Results of a triaxial accelerometer-based method were evaluated against video observation scores (criterion measure). Study 1: Subjects performed basic mobility-related activities (walking, lying, sitting, standing) in a fixed and free sequence. Study 2: Subjects were monitored while doing similar activities as in study 1 and while doing usual domestic activities.

Setting: Study 1: Standardized set-up in a movement laboratory. Study 2: Home environment.

Participants: (N=37) Study 1: Patients with PD (n=32; mean age +/- SD, 67.3+/-6.6y; mean disease duration +/- SD, 6.1+/-3.4y). Study 2: Patients with PD (n=5; mean age +/- SD, 76.0+/-7.3y; mean disease duration +/- SD, 3.8+/-4.7y).

Interventions: Not applicable.

Main outcome measures: The degree of correspondence between the monitor and the video observation for the duration of each activity. Overall agreement, sensitivity, specificity, and positive predictive values were calculated.

Results: Study 1: Overall agreement ranged between 69.8% and 90.8% (fixed sequence) and 57.5% and 96.9% (free sequence). Study 2: Overall agreement ranged between 60.0% and 89.2%. Lying, sitting (home), and walking were detected most accurately with mean sensitivity varying from 81.7% to 99.9%. Lower values were found for sitting (laboratory), standing, and shuffling.

Conclusions: This triaxial monitor system is a practical and valuable tool for objective, continuous evaluation of walking and postures in patients with mild to moderate PD. Detection of sitting and standing requires further fine-tuning.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Disability Evaluation*
  • Female
  • Gait*
  • Humans
  • Male
  • Middle Aged
  • Observer Variation
  • Parkinsonian Disorders / diagnosis*
  • Parkinsonian Disorders / physiopathology
  • Physical Therapy Modalities
  • Posture*
  • Reproducibility of Results