Differentiating fall-prone and healthy adults using local dynamic stability

Variability in kinematic and spatio-temporal gait parameters has long been equated with stability and used to differentiate fallers from non-fallers. Recently, a mathematically rigorous measure of local dynamic stability has been proposed based on the non-linear dynamics theory to differentiate fallers from non-fallers. This study investigated whether the assessment of local dynamic stability can identify fall-prone elderly individuals who were unable to successfully avoid slip-induced falls. Five healthy young, four healthy elderly and four fall-prone elderly individuals participated in a walking experiment. Local dynamic stability was quantified by the maximum Lyapunov exponent. The fall-prone elderly were found to exhibit significantly lower local dynamic stability (i.e. greater sensitivity to local perturbations), as compared to their healthy counterparts. In addition to providing evidence that the increased falls of the elderly may be due to the inability to attenuate/control stride-to-stride disturbances during locomotion, the current study proposed the opportunity of using local dynamic stability as a potential indicator of risk of falling. Early identification of individuals with a higher risk of falling is important for effective fall prevention. The findings from this study suggest that local dynamic stability may be used as a potential fall predictor to differentiate fall-prone adults.

[1]  S. Turbanski Postural Instability in Parkinsons’s Disease , 2009 .

[2]  Jian Liu,et al.  Local Dynamic Stability Assessment of Motion Impaired Elderly Using Electronic Textile Pants , 2008, IEEE Transactions on Automation Science and Engineering.

[3]  Thurmon E Lockhart,et al.  Dynamic stability differences in fall-prone and healthy adults. , 2008, Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology.

[4]  Thurmon E Lockhart,et al.  An integrated approach towards identifying age-related mechanisms of slip initiated falls. , 2008, Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology.

[5]  Jonathan B Dingwell,et al.  Differences between local and orbital dynamic stability during human walking. , 2007, Journal of biomechanical engineering.

[6]  T. Lockhart,et al.  Age-related slip avoidance strategy while walking over a known slippery floor surface. , 2007, Gait & posture.

[7]  Scott A. England,et al.  The influence of gait speed on local dynamic stability of walking. , 2007, Gait & posture.

[8]  K. Holt,et al.  Gait Characteristics of Elderly People With a History of Falls: A Dynamic Approach , 2006, Physical Therapy.

[9]  Jonathan B Dingwell,et al.  Intra-session reliability of local dynamic stability of walking. , 2006, Gait & posture.

[10]  Thurmon E Lockhart,et al.  Relationship between hamstring activation rate and heel contact velocity: factors influencing age-related slip-induced falls. , 2006, Gait & posture.

[11]  A. Geurts,et al.  Dynamical structure of center-of-pressure trajectories in patients recovering from stroke , 2006, Experimental Brain Research.

[12]  Kevin P Granata,et al.  Stability of Dynamic Trunk Movement , 2006, Spine.

[13]  Age-related upper limb response strategies to unexpected slips , 2006 .

[14]  J. Dingwell,et al.  Kinematic variability and local dynamic stability of upper body motions when walking at different speeds. , 2006, Journal of biomechanics.

[15]  Jonathan B. Dingwell,et al.  A direct comparison of local dynamic stability during unperturbed standing and walking , 2006, Experimental Brain Research.

[16]  Salim Ghoussayni,et al.  Assessment and validation of a simple automated method for the detection of gait events and intervals. , 2004, Gait & posture.

[17]  N. Stergiou,et al.  The effect of the walking speed on the stability of the anterior cruciate ligament deficient knee. , 2004, Clinical biomechanics.

[18]  K. Matsuoka,et al.  Effect of prolonged free-walking fatigue on gait and physiological rhythm. , 2004, Journal of biomechanics.

[19]  J. Nielsen,et al.  Segmental reflexes and ankle joint stiffness during co-contraction of antagonistic ankle muscles in man , 1994, Experimental Brain Research.

[20]  Mehmet Emre Çek,et al.  Analysis of observed chaotic data , 2004 .

[21]  T. Lockhart,et al.  Effects of age-related gait changes on the biomechanics of slips and falls , 2003, Ergonomics.

[22]  N. Stergiou Innovative Analyses of Human Movement , 2003 .

[23]  N. Stergiou,et al.  Nonlinear dynamics indicates aging affects variability during gait. , 2003, Clinical biomechanics.

[24]  P. Morasso,et al.  Ankle muscle stiffness alone cannot stabilize balance during quiet standing. , 2002, Journal of neurophysiology.

[25]  Jeffrey M. Hausdorff,et al.  Gait variability and fall risk in community-living older adults: a 1-year prospective study. , 2001, Archives of physical medicine and rehabilitation.

[26]  D. Sternad,et al.  Local dynamic stability versus kinematic variability of continuous overground and treadmill walking. , 2001, Journal of biomechanical engineering.

[27]  J. Dingwell,et al.  Nonlinear time series analysis of normal and pathological human walking. , 2000, Chaos.

[28]  D. Sternad,et al.  Slower speeds in patients with diabetic neuropathy lead to improved local dynamic stability of continuous overground walking. , 2000, Journal of biomechanics.

[29]  L. Schutte,et al.  An index for quantifying deviations from normal gait. , 2000, Gait & posture.

[30]  D. Winter,et al.  Stiffness control of balance in quiet standing. , 1998, Journal of neurophysiology.

[31]  L. Cao Practical method for determining the minimum embedding dimension of a scalar time series , 1997 .

[32]  H Nagasaki,et al.  Optimal walking in terms of variability in step length. , 1997, The Journal of orthopaedic and sports physical therapy.

[33]  Jeffrey M. Hausdorff,et al.  Increased gait unsteadiness in community-dwelling elderly fallers. , 1997, Archives of physical medicine and rehabilitation.

[34]  B. E. Maki,et al.  Gait Changes in Older Adults: Predictors of Falls or Indicators of Fear? , 1997, Journal of the American Geriatrics Society.

[35]  E. D. Ilsar,et al.  Remote monitoring of health status of the elderly at home. A multidisciplinary project on aging at the University of New South Wales. , 1995, International journal of bio-medical computing.

[36]  Howard Jay Chizeck,et al.  Quantitative measurement of stability in human gait through computer simulation and Floquet analysis , 1995, Proceedings of 17th International Conference of the Engineering in Medicine and Biology Society.

[37]  W. H. Warren,et al.  Why change gaits? Dynamics of the walk-run transition. , 1995, Journal of experimental psychology. Human perception and performance.

[38]  L. Tsimring,et al.  The analysis of observed chaotic data in physical systems , 1993 .

[39]  M. Rosenstein,et al.  A practical method for calculating largest Lyapunov exponents from small data sets , 1993 .

[40]  B. R. Bloem,et al.  Postural instability in Parkinson's disease , 1992, Clinical Neurology and Neurosurgery.

[41]  D. Winter,et al.  Biomechanical walking pattern changes in the fit and healthy elderly. , 1990, Physical therapy.

[42]  David A. Winter,et al.  Biomechanics and Motor Control of Human Movement , 1990 .

[43]  G. Davies Stability theory: An introduction to the stability of dynamic systems and rigid bodies, 2nd edn, Horst Leipholz, B. G. Teubner and Wiley, chichester. 1987. No. of pages: 368. Price £32.00. ISSN: 47191181 , 1988 .

[44]  H. H. E. Leipholz,et al.  Stability Theory: An Introduction to the Stability of Dynamic Systems and Rigid Bodies , 1987 .

[45]  F. Takens Detecting strange attractors in turbulence , 1981 .

[46]  James P. Crutchfield,et al.  Geometry from a Time Series , 1980 .

[47]  R. Guimarães,et al.  Characteristics of the gait in old people who fall. , 1980, International rehabilitation medicine.

[48]  O. Edholm,et al.  The assessment of gait and mobility in the elderly. , 1979, Age and ageing.