Article

Parkinson's disease (PD) degrades balance control. Haptic (touch and
proprioception) feedback from light contact with a stationary surface inadequate
to mechanically stabilize balance improves balance control in healthy people. In
this study we tested whether PD impairs use of haptic cues independent of
mechanical support to control balance. We measured postural sway in thirteen
individuals with PD (H&Y 1-3, median=2, Q1=2, Q3=2) and thirteen age-matched
controls balancing in a widened, sharpened Romberg stance in four conditions:
eyes-closed, no manual contact; eyes-closed light-touch contact (<1N),
eyes-closed, unrestricted contact; and eyes-open, no contact. To determine
whether PD-severity affects any of these balance strategies, PD participants were
tested on- and off-medication, and using the more- and less-affected body side in
the stance and manual contact. Individuals with PD simultaneously maintained
non-supportive fingertip contact and balance in this task without practice. PD
participants swayed more than control participants (ML CP p=0.010; shoulder
p<0.001), but manual contact reduced sway. Non-supportive manual contact
stabilized balance more than vision (p<0.05). PD-severity factors had no
significant effect (p>0.05). We conclude the effect of PD on balance is not
specific to vision or haptic feedback. Nevertheless, haptic cues from manual
contact, independent of mechanical support, improve balance control in
individuals with PD. We discuss the implication that PD or associated
dopaminergic pathways do not directly affect haptic feedback balance control
mechanisms, including arm/posture coordination and proprioceptive integration.
CI - Copyright (c) 2012 Elsevier B.V. All rights reserved.

Langue : ANGLAIS