Using detrended fluctuation analysis (DFA) to analyze whether vibratory insoles enhance balance stability for elderly fallers

Arch Gerontol Geriatr. 2012 Nov-Dec;55(3):673-6. doi: 10.1016/j.archger.2011.11.008. Epub 2011 Dec 12.

Abstract

Falls are a common and devastating problem among elderly people. In a previous study, vibratory insoles were developed to improve postural stability for elderly fallers. To verify the effects of vibratory insoles, a two-stage experiment was conducted to collect center of pressure (COP) signals from 26 elderly fallers and 16 healthy young subjects while standing still. The DFA is used to analyze the behavior of different time-series data obtained from the trajectory of COP. Postural stability was compared by the DFA scaling exponent between a control condition (before using vibratory insoles) and a vibration condition (after using vibratory insoles). For elderly fallers, DFA scaling exponents 95% confidence interval were [1.434, 1.547] and [1.329, 1.451] under control and vibration conditions in the anteroposterior (AP) direction, respectively. The experimental results revealed that temporary stimuli of appropriate amplitude produced by vibration insoles enhanced postural stability in elderly fallers and was more obvious in the AP direction.

MeSH terms

  • Accidental Falls / prevention & control*
  • Adult
  • Aged
  • Aged, 80 and over
  • Female
  • Foot Orthoses*
  • Humans
  • Male
  • Models, Theoretical
  • Postural Balance*
  • Vibration / therapeutic use*
  • Young Adult