Fear-avoidance beliefs are associated with changes of back shape and function

Supplemental Digital Content is Available in the Text. Fear-avoidance beliefs are associated with reduction of back movements. This implies their importance during chronification of pain and their potential for therapeutic approaches. Introduction: Psychosocial function in people with chronic low back pain (cLBP) is often impaired, indicating poor well-being. Fear-avoidance beliefs (FAB) are common concomitants of cLBP. Fear-avoidance beliefs are gaining attention as a potential prognostic factor for chronification and resulting disability in cLBP. This article aims to examine the associations of back function with FAB. Methods: This study presents data from a cohort study (DRKS00027907). In the present cross-sectional analyses, we included 914 participants (480 nonchronic LBP [ncLBP], 227 cLBP, 207 asymptomatic). Fear-avoidance beliefs were assessed using the fear-avoidance belief questionnaire (FABQ). The association between the FAB and clinical measures (Ott and Schober test, the sit-to-stand test [STS], and the finger-floor distance [FFD]) were analyzed. Back shape and function were also measured using a noninvasive device. The association between FABQ scores and clinical measures was assessed using age, body mass index, sex, and pain intensity–adjusted multiple linear regression models. Results: Associations between FAB and both clinical (Ott, Schober, STS, FFD) and noninvasive device measures were small. All relevant clinical measures were attenuated in individuals with elevated FAB. Discussion: We were able to demonstrate the association of both back shape and function in both clinical tests and noninvasive device measurements with self-reported fear-avoidance beliefs. However, the effect sizes were small. This may be attributed to the different assessment methods (objective vs self-report), resulting in reduced common method variance. In addition to the FAB, there may be other factors (eg, altered neuronal pathways; actual avoidance behavior such as reduced physical activity) that contribute to functional impairment.