How additional visual feedback of the movements between center of pressure and vertically projected center of gravity can be used by hemiparetic patients.
OBJECTIVE
In healthy adults, the beneficial effect of providing additional visual feedback (VFB) with a delay of either the center of pressure (CP) or the difference between CP movements and center of gravity (CP-CGv) movements was previously demonstrated and explained by their capacity to decrease their CP-CGv movements. The present study seeks to demonstrate whether similar trends could be observed in hemiparetic patients.


METHODS
Posturographic measurements were recorded in 56 hemiparetic patients in 3 VFB conditions: (1) CP in real time (VFBCP0), (2) CP with a 600-ms delay (VFBCP600), and (3) CP-CGv with a 600-ms delay (VFBCP-CG600). A condition without VFB (eyes open [EO]) was also included. The individual capacity to lower CP-CGv movements as compared to the reference VFBCP0 condition was assessed using dependency coefficients (ie, average surface covered by the CP-CGv displacements in an experimental condition relative to the VFBCP0 condition) in the VFBCP600, VFBCP-CG600, and EO conditions.


RESULTS
Reduced CP-CGv movements were only obtained for half of the patients for the conditions with delay or without VFB. Significant linear correlations revealed that the most successful patients are characterized by reduced CP-CGv movements in these conditions and in the EO condition. In contrast, a poor correlation was found with the patients' clinical scores.


CONCLUSIONS
Based on the behavioral profile of a patient able to use these VFB techniques effectively, this study emphasizes the complementary nature of the various conditions proposed by the VFB technique and provides insights for establishing rehabilitation protocols based on this VFB technique.
Laboratoire de Physiologie de l'Exercice, Université de Savoie, Le Bourget du Lac, France.
Patrice R
PR
Rougier
Samir
S
Boudrahem
D000368:Aged; D056228:Feedback, Sensory / Q000502:physiology*; D005260:Female; D006112:Gravitation; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D010291:Paresis / Q000503:physiopathology* / Q000534:rehabilitation; D004856:Postural Balance; D011237:Predictive Value of Tests; D011312:Pressure; D013997:Time Factors