Abstract
The paper outlines a biomechanical approach to quantifying anticipatory postural adjustments in the elderly. The measurement problems that occur in applying the biomechanical approach to elderly subjects are described and the ‘signal-to-noise’ properties of three candidate measures are compared, using data from volitional unilateral arm-raise tests performed on 100 elderly subjects. The results suggest that changes in vertical ground reaction force provide the greatest potential for accurate measurement of anticipatory adjustments, in comparison with changes in horizontal force or centre-of-pressure displacement. By normalising the anticipatory change in vertical ground reaction force with respect to the vertical perturbation force induced by the arm motion, a measure of relative anticipatory response is derived. The use of this measure, as well as its limitations, are demonstrated by analysing its relationship to actual falling risk, monitored prospectively in the elderly subject population. The findings showed evidence of larger relative anticipatory adjustments in the subjects who experienced recurrent falls, and it is suggested that these responses may be indicative of disordered motor programming. However, to detect these differences it was necessary to average responses over multiple trials and to exclude trials with very small arm acceleration or very large baseline ‘noise’ (associated with ongoing postural sway). The need to screen and exclude data would seem to limit the practical utility of this approach in testing elderly populations.
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References
Bouisset, S. andZattara, M. (1981) A sequence of postural movements precedes voluntary movement.Neurosci. Lett.,22, 263–270.
Bouisset, S. andZattara, M. (1987) Biomechanical study of the programming of anticipatory postural adjustments associated with voluntary movements.J. Biomech.,20, 735–742.
Conover, W. J. andIman, R. L. (1981) Rank transformations as a bridge between parametric and nonparametric statistics.The American Statistician,35, 124–133.
Inglin, B. andWoollacott, M. (1988) Age-related changes in anticipatory postural adjustments associated with arm movements.J. Gerontol: Med. Sci.,43, M105-M113.
Maki, B. E. (1987)A posture control model and balance test for the prediction of relative postural stability. Ph.D. Thesis, University of Strathclyde, Glasgow.
Maki, B. E., Holliday, P. J. andFernie, G. R. (1987) A posture control model and balance test for the, prediction of relative postural stability.IEEE Trans.,BME-34, 797–810.
Maki, B. E. andFernie, G. R. (1988) A system identification approach to balance testing.Progr. in Brain Res.,76, 297–306.
Maki, B. E., Holliday, P. J. andFernie, G. R. (1990) Aging and postural control: a comparison of spontaneous and induced sway balance tests.J. Am. Geriatrics Soc.,38, 1–9.
Maki, B. E., Holliday, P. J. andTopper, A. K. (1991) Fear of falling and postural performance in the elderly.J. Gerontol.: Med. Sci.,46, M123-M131.
Neter, J., Wasserman, W. andKutner, M. H. (1985)Applied linear statistical models, 2nd edn. Richard D. Irwin, Inc., Homewood, Illinois, 615–617.
Riach, C. L. andHayes, K. C. (1984) The interaction of centre of pressure and centre of gravity in postural control. Proc. Human Locomotion III (3rd Ann. Conf. Canad. Soc. for Biomech., Winnipeg, 1984) 79–80.
Riach, C. L. andHayes, K. C. (1990). Anticipatory postural control in children.J. Motor Behav.,22, 250–266.
Riach, C. L., Hayes, K. C. andLucy, S. D. (1992) Changes in centre-of-pressure ground reaction forces prior to rapid arm movement in normal subjects and patients with cerebellar ataxia.Clin. Biomech.,7, 208–214.
Tinetti, M. E. (1986) Performance-oriented assessment of mobility problems in elderly patients.J. Am. Geriatrics Soc.,34, 119–126.
Winter, D. A. (1979)Biomechanics of human movement. John Wiley, New York, 151.
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Maki, B.E. Biomechanical approach to quantifying anticipatory postural adjustments in the elderly. Med. Biol. Eng. Comput. 31, 355–362 (1993). https://doi.org/10.1007/BF02446688
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DOI: https://doi.org/10.1007/BF02446688