Influence of simulated neuromuscular noise on movement variability and fall risk in a 3D dynamic walking model

Paulien E. Roos, Jonathan Dingwell

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

People at risk of falling exhibit increased gait variability, which may predict future falls. However, the causal mechanisms underlying these correlations are not well known. Increased neuronal noise associated with aging likely leads to increased gait variability, which could in turn lead to increased fall risk. This paper presents a model of how changes in neuromuscular noise independently affect gait variability and probability of falling, and aims to determine the extent to which changes in gait variability directly predict fall risk. We used a dynamic walking model that incorporates a lateral step controller to maintain lateral stability. Noise was applied to this controller to approximate neuromuscular noise in humans. Noise amplitude was varied between low amplitudes that did not induce falls and high amplitudes for which the model always fell. With increases in noise amplitude, the model fell more often and after fewer steps. Gait variability increased with noise amplitude and predicted increased probability of falling. Importantly, these relationships were not linear. At either low gait variability or very high gait variability, small increases in noise and variability affected probability of falling very little. Conversely, at intermediate noise and/or variability levels, the same small increases resulted in large increases in probability of falling. Our results validate the idea that age-related increases in neuromuscular noise likely play a direct contributing role in increasing fall risk. However, neuromuscular noise remains only one of many important factors that need to be considered. These findings have important implications for fall prevention research and practice.

Original languageEnglish (US)
Pages (from-to)2929-2935
Number of pages7
JournalJournal of Biomechanics
Volume43
Issue number15
DOIs
StatePublished - Nov 16 2010

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Walking
Noise
Accidental Falls
Gait
Controllers
Aging of materials

All Science Journal Classification (ASJC) codes

  • Orthopedics and Sports Medicine
  • Rehabilitation
  • Biophysics
  • Biomedical Engineering

Cite this

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Influence of simulated neuromuscular noise on movement variability and fall risk in a 3D dynamic walking model. / Roos, Paulien E.; Dingwell, Jonathan.

In: Journal of Biomechanics, Vol. 43, No. 15, 16.11.2010, p. 2929-2935.

Research output: Contribution to journalArticle

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