Improvements in forward bending are related to improvements in pain and disability during cognitive functional therapy for people with chronic low back pain

OBJECTIVE: To investigate whether improvements in forward bending were related to improvements in pain and disability in people with chronic low back pain (CLBP) who were undergoing Cognitive Functional Therapy (CFT). DESIGN: Longitudinal observational study. METHODS: Two hundred and sixty-one participants with CLBP received CFT. Forward bending was assessed at each treatment session over 13 weeks (an average of 4.3 timepoints per participant [range, 1-8]). Spinal range of motion (ROM) and velocity were recorded using 2 inertial measurement units located at T12 and S2. Participants reported (1) average pain intensity (0-10 scale) (pain) and (2) pain-related activity limitation (Roland Morris Disability Questionnaire [disability]) via online questionnaires at 0, 3, 6, and 13 weeks. Multivariate multilevel models were used to evaluate associations between individual rates of change over time for 3 spinal movement measures (trunk velocity, trunk ROM, lumbar ROM) and pain/disability. RESULTS: Strong correlations were observed for increased trunk velocity with reduced pain (r = -0.81; 95% CI: -0.98, -0.05) and with reduced disability (r = -0.77; 95% CI: -0.95, -0.22). Moderate correlations were observed between increased trunk ROM with reduced pain (r = -0.37; 95% CI: -0.67, 0.04) and with reduced disability (r = -0.32; 95% CI: -0.6, 0.03). There was no evidence of association between changes in lumbar ROM and pain (r = -0.46; 95% CI: -0.90, 0.44) or disability (r = -0.01; 95% CI: -0.56, 0.55). CONCLUSION: Reductions in pain and disability were strongly correlated with increased trunk velocity in people with CLBP who were undergoing CFT. These findings are consistent with CFT that explicitly trains "nonprotective" spinal movement.