Abstract
BACKGROUND/PURPOSE: Chronic low back pain affects how individuals bend. Whether pain self-efficacy, a term describing one's confidence in their ability to perform activities despite experiencing pain, affects how much people with chronic low back pain bend their lumbar spine and hips in response to exercise is unknown. The aim of this study was to investigate whether baseline pain self-efficacy influenced either lumbar or hip flexion range of motion over the first quarter of forward bending post-exercise intervention. STUDY DESIGN: Cohort study. # MethodsNew patients (aged 18-65 years old) presenting to a physiotherapy clinic with moderate-severe chronic low back pain-related disability who had not undergone spinal or lower limb surgery underwent assessment of pain self-efficacy (using the Pain Self-Efficacy Questionnaire; range 0-60 points; higher indicates better), pain intensity and kinesiophobia prior to 12-weeks of an exercise rehabilitation program. Two outcome measures (lumbar and hip flexion range of motion over the first quarter of forward bending from stance) were assessed at baseline, 6 and 12-weeks. Multivariable linear mixed-effects modelling was performed for each outcome. RESULTS: Sixty-nine participants were recruited. At baseline, mean pain self-efficacy score was 44.0 (SD=10.0; range 22 to 60) points. For every 10-point increase in baseline pain self-efficacy, lumbar flexion range of motion during initial forward bending decreased by a mean 1.47 (95% CI: -2.68, -0.27), 0.51 (95% CI: -1.41, 0.39) and 0.94 (95% CI: -1.75, -0.13) degrees, while hip flexion range of motion decreased by a mean 1.74 (95% CI: -3.68, 0.21), 1.64 (95% CI: -3.70, 0.41) and 1.43 (95% CI: -3.34, 0.48) degrees at baseline, 6 and 12-weeks, respectively. CONCLUSIONS: At baseline, higher pain self-efficacy was associated with reduced lumbar flexion during initial forward bending. However, pain self-efficacy did not influence initial forward bending following a 12-week exercise intervention. LEVEL OF EVIDENCE: 2.