Article

Correlations between force plate measures for assessment of balance.

Department of Systems and Control, Uppsala University, P.O. Box 27, 751 03, Uppsala, Sweden.
Clinical Biomechanics (impact factor: 2.07). 06/2000; 15(5):365-9. pp.365-9
Source: PubMed

ABSTRACT To compare different force plate measures for assessment of postural stability during normal standing. Five types of measures were analysed: (1) The standard deviation of the horizontal ground reaction force, (2) the standard deviation of the centre of pressure, (3) the mean velocity of the centre of pressure, (4) movement strategy measures, and (5) the standard deviation of the vertical ground reaction force.
Force plate measures such as types 1-3 are frequently used, but they seem to have limited usefulness for assessment of balance on an individual level. Hence, there is a need to investigate alternative force plate measures (such as types 4 and 5).
Force plate measures for 20 stroke patients were (a) compared to each other, and (b) compared to a clinical balance test, called Berg's balance test.
There was generally a significant correlation (P<0.01) between measures of types 1-3. The movement strategy measures were not significantly correlated to any of the other measures. The vertical force measure was only significantly correlated to the antero-posterior mean velocity of the centre of pressure. There was a significant correlation between (a) Berg's balance test and the vertical force measure (r(s)=-0.76), and (b) the static part of Berg's balance test and the antero-posterior mean velocity of the centre of pressure (r(s)=-0.6).
Measures of type 1, 2, 4 and 5 seem to quantify different aspects of human standing. The results also indicate that Berg's balance test and the vertical force measure quantify a similar aspect of the postural stability.
The results from this study may facilitate the understanding and interpretation of force plate measures.

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Keywords

20 stroke patients
 
alternative force plate measures
 
Berg's balance test
 
clinical balance test
 
different aspects
 
different force plate measures
 
force plate measures
 
horizontal ground reaction force
 
individual level
 
mean velocity
 
measures
 
movement strategy measures
 
postural stability
 
similar aspect
 
standard deviation
 
static part
 
type 1
 
types 4
 
vertical force measure
 
vertical ground reaction force
 

A Karlsson