Evaluation of postural balance using the biodex balance system in subjects with and without low back pain

ABSTRACT

To evaluate the reliabiity of dynamic standing balance in individuals with and without low back pain [LBP] using Biodex Balance System [BBS] and to compare the balance indices between two groups. Across-sectional non-experimental design. Biomechanics Laboratory and Saba spine specific physical therapy clinic, University of social welfare and rehabilitation sciences, Tehran, Iran. Twenty three male patients with LBP [mean age 30.4 +/- 6.5 years] and twenty age-matched healthy male subjects [mean age 29.8 +/- 6.4 years] participated in this study. Medial-Lateral stability index [MLSI], Anterior-posterior stability index [APSI] and an Overall stability index [OSI] were measured in two measurement sessions using the BBS. Balance was measured in four conditions; bilateral and unilateral stance with eyes open and eyes closed; over a period of 20s. The results showed that ICC in healthy subjects and those with LBP was between [0.91-0.95] and [0.88-0.96] respectively. The Bland-Altman plot of agreement in balance scores between tests and retests demonstrated good agreement. A significant difference was found in MLSI and OSI between subjects with and without LBP. However, no significant difference was detected in APSI between two groups. The findings of this study showed high reliability for BBS to evaluate dynamic postural balance in subjects with and without LBP. It seems that MLSI and 051 significantly differ between subjects with and without LBP