Experimental Brain Research

, Volume 181, Issue 4, pp 561–570

A new measure for quantifying the bilateral coordination of human gait: effects of aging and Parkinson’s disease

Authors

    • Movement Disorders UnitTel-Aviv Sourasky Medical Center
  • Nir Giladi
    • Movement Disorders UnitTel-Aviv Sourasky Medical Center
    • Department of Physical Therapy, Sackler Faculty of MedicineTel-Aviv University
    • Department of Neurology, Sackler Faculty of MedicineTel-Aviv University
  • Jeffrey M. Hausdorff
    • Movement Disorders UnitTel-Aviv Sourasky Medical Center
    • Department of Physical Therapy, Sackler Faculty of MedicineTel-Aviv University
    • Division on AgingHarvard Medical School
Research Article

DOI: 10.1007/s00221-007-0955-7

Cite this article as:
Plotnik, M., Giladi, N. & Hausdorff, J.M. Exp Brain Res (2007) 181: 561. doi:10.1007/s00221-007-0955-7

Abstract

The bilateral coordination of locomotion has been described in detail in animal studies and to some degree in man; however, the mechanisms that contribute to the bilateral coordination of gait in humans are not fully understood. The objective of the present study was to develop a measure for quantifying the bilateral coordination of gait and to evaluate the effects of aging and Parkinson’s disease (PD) on this new metric. To this end, we compared the gait of healthy older adults to that of healthy young adults and patients with PD. Specifically, we defined the stride duration of one foot as a gait cycle or 360°, determined the relative timing of contra-lateral heel-strikes, and defined this as the phase, ϕ (ideally, ϕ = 180° for every step). The sum of the coefficient of variation of ϕ and the mean absolute difference between ϕ and 180° was defined as the phase coordination index (PCI), representing variability and inaccuracy, respectively, in phase generation. PCI values were higher (poorer bilateral coordination) in patients with PD in comparison to the healthy older adults (P < 0.006). Although gait speed and stride time variability were similar in the healthy young and older adults, PCI values were significantly higher among the healthy elderly subjects compared to the young adults (P < 0.001). Regression analysis suggests that only about 40% of the variance in the values of PCI can be explained by the combination of gait asymmetry (as defined by the differences in each leg’s swing times), gait speed and stride time variability, pointing to the independent nature of this new metric. This study demonstrates that bilateral coordination of gait deteriorates with aging, further deteriorates in PD, and is not strongly associated with other spatio-temporal features of gait.

Keywords

Blateral coordinationAgingParkinson’s diseaseGait

Copyright information

© Springer-Verlag 2007