The main objective of this study was the estimation of intrasession reliability of the limits of stability (LOS) test conducted on a force platform as an alternative measurement to standard posturography in quiet standing. Fifteen healthy adults took part in the experiment. The standardized measurement protocol of the LOS test was proposed. It consists of three phases - 1st phase - 10s of quiet standing, 2nd phase - the maximal forward leaning in a self paced manner, and 3rd phase - maintenance of maximal forward leaning position. The analysis of variance Friedman's ANOVA and Repeated Measures ANOVA/MANOVA was used to diagnose the differences between 10 consecutive trials of the LOS test. In order to establish reliability of the test, the intraclass correlation (ICC) procedure was used. We presented different ways of maximal center of pressure (COP) excursion estimates. The results of this study show no significant differences between the chosen parameters of the LOS test. Moreover, the measurement of the range of COP excursion, which is most commonly analyzed in such tests, showed to be quite reliable with ICC2,1 above .85. LOS test conducted along the standard procedure should be considered as a very useful method in clinical and research conditions. Still the specific parameters of the LOS test should be given more thorough insight, but it is a very good alternative to quiet standing posturography.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.