Article

Literature confirms the effects of vision and stance on body sway and indicates
possible interactions between the two. However, no attempts have been made to
systematically compare the effect of vision on the different types of stance
which are frequently used in clinical and research practice. The biomechanical
changes that occur after changing shape and size of the support surface suggest
possible sensory re-weighting might take place. The purpose of this study was to
assess the effect of vision on body sway in relation to different stance
configurations and width. Thirty-eight volunteers performed four quiet stance
configurations (parallel, semi-tandem, tandem and single leg), repeating them
with open and closed eyes. Traditional parameters, recurrence quantification
analysis and sample entropy were analyzed from the CoP trajectory signal.
Traditional and recurrence quantification analysis parameters were affected by
vision removal and stance type. Exceptions were frequency of oscillation, entropy
and trapping time. The most prominent effect of vision elimination on traditional
parameters was observed for narrower stances. A significant interaction effect
between vision removal and stance type was present for most of the parameters
observed (p<0.05). The interaction effect between medio-lateral and
antero-posterior traditional parameters differed in linearity between stances.
The results confirm the effect of vision removal on the body sway. However, for
the medio-lateral traditional parameters, the effects did not increase linearly
with the change in width and stance type. This suggests that removal of vision
could be more effectively compensated by other sensory systems in semi-tandem
stance, tandem and single legged stance.
CI - Copyright (c) 2013 Elsevier B.V. All rights reserved.

Langue : ANGLAIS