Studying the correlation between balance assessment by Biodex Stability System and Berg Scale in stroke individuals

Balance disorders are considered to be a serious clinical manifestation after stroke. Therefore, to assess stroke patients' balance performance, use of a quantitative method appears essential. A fundamental step would be the approval of the efficiency of the measurement instruments. The current study aimed to investigate correlations between balance assessment as examined by Biodex Stability System (BSS) and the clinical Berg Balance Scale (BBS) in post-stroke hemiparesis.

Twenty-five stroke survivors and 25 healthy age-sex matched subjects were recruited. The subjects were assessed using BSS during 3 days, with a 24-h interval. The high interclass correlation coefficient (ICC) values showed that the system was reliable enough to continue the study. The clinical evaluation was performed by the standard BBS.

There was a significant moderate negative correlation between the Biodex overall indices and BBS scores in the stroke groups (r_avg = -0.68) and in the healthy cohort (r_avg = -0.55). Also, a significant moderate negative correlation was found between the Biodex antero-posterior stability indices and BBS scores in the stroke groups (r_avg = -0.67) and in healthy cohort (r_avg = -0.55). The correlation between the Biodex mediolateral stability indices and BBS scores was moderate to low in the stroke and healthy groups (r_avg = -0.67 and -0.39 respectively).

Moderate negative correlation between the stability indices of the Biodex Stability System and BBS scores indicates that dynamic balance status of the participants partially reflects their functional balance status.