The relationship between pain, fear-avoidance beliefs and postural stability in subjects with non-specific chronic low back pain

Introduction: Fear of pain is related to disability and chronicity of low back pain. The aim of this study was to investigate the relation between fear avoidance beliefs (FAB) and postural stability and the influence of specific training on postural stability and FAB in individuals with non specific chronic low back pain (NSCLBP). Materials and Methods: Twenty seven females with NCLBP were recruited in this quasi-experimental study. Pain intensity, FAB, and disability were recorded using the questionnaires. The force plate was used to measure the postural stability. Abdominal and back muscle endurance was measured respectively by sit up and Biering-Sorensen tests. All tests were repeated ne week and one month after a short term specific training for FAB. Repeated measure analysis was used to compare the variables. To evaluate the association between variables Pearson correlation coefficient and mixed model analysis were used. All data were analyzed by SPSS, version16. Results: Pain intensity, FAB, and disability scores showed a significant reduction after intervention (P < 0.01). The time of sit up, Sorensen and single leg stance tests prominently increased (P < 0.01). Center of pressure (COP) excursion and velocity variables faced with a considerable decrease (P < 0.01). Pain intensity was mainly related to cop excursion and velocity during unilateral standing (P < 0.01) but there is no relation between FAB and the parameters of postural stability. However, trend of changes in FAB was related to trend of changes in cop excursion and velocity during unilateral standing in mediolateral plan (P = 0.04). Conclusion: Changes in FAB was related to the changes in COP excursion and velocity during unilateral standing. Specific training for FAB resulted in pain intensity reduction, FAB, and disability scores. It also led to an improvement he postural stability as well as increasing the time of sit up, Biering-Sorensen and single leg stance tests in subjects with NSCLBP. Keywords: Chronic low back pain, Postural stability, Fear avoidance belief