Background Chronic low back pain (CLBP) affects from 12-33% of the adult population and the cause of its chronicity still unknown. Change in postural control is a factor involved and studies are not conclusive, mainly in functional activities.
Objectives To assess postural control in individuals with and without non-specific CLBP during functional activities orthostatic and one leg stand.
Methods Sample consisted of 44 individuals divided into: Chronic Low Back Pain (CLBP, n=21) with CLBP and Control Group (CG, n=23) without CLBP. They had their balance assessed in a force platform NeuroCom Balance Master using two tests: a) Modified Clinical Test of Sensory Interaction and Balance (CTSIBm) thatmeasured the center of pressure (COP) in four experimental conditions in standing position: eyes open and stable surface, eyes closed and stable surface, eyes open and unstable surface, eyes closed and unstable surface; and b) One leg stand test that measured the COP on one experimental condition: eyes open and stable surface, standing on the left leg first and then the right. Pain severity was assessed by a visual analogue scale and disability by the Roland-Morris Questionnaire. Statistical analysis: normality was assessed using the Shapiro-Wilk test. Normally distributed variables were compared with the Student t-test. Non-parametric variables were compared using the Mann-Whitney test. Significance was established at the 5% level.
Results The groups are homogeneous in age, weight, height and body mass index. CLBP group shows deficits in postural control compared to CG showing greater postural sway in quite standing condition with eyes closed and unstable surface in CTSIBm (p<0.05): Trace length [CLBP – 1432.82 (73.27) vs CG – 1187.77 (60.30)], Mean velocity [CLBP – 12.97 (0.84) vs CG – 10.55 (0.70)], Root Mean Square (RMS) sagittal plane [CLBP – 1.21 (0.06) vs CG – 1.04 (0.04)] and area [CLBP – 24.27 (2.47) vs CG – 16.45 (1.79)]. CLPB group showed greater sway in frontal plane in the one leg stand test (p<0.05): RMS frontal plane [CLBP – 0.43 (0.02) vs CG – 0.55 (0.04)].
Conclusions Individuals with non-specific CLBP have impaired postural control relative to their controls, as evidenced by increased oscillation of COP. Differences were more pronounced in eyes closed conditionand unstable surface.
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Disclosure of Interest None Declared