Lumbopelvic rhythm analysis by quartiles: Identification of differences in lumbar and pelvic contribution during trunk flexion and extension in subjects with low back pain of different origin. A case-control study

Low back pain (LBP) can alters spinal kinematics. However, for adequate clinical care, a better understanding of lumbopelvic biomechanical behaviour according to the type of LBP is required. Our objectives were to identify differences in lumbopelvic rhythm (LPR) between subjects with acute low back pain (aLBP), axial spondyloarthritis (axSpA) and healthy subjects. As well as to identify correlations between LPR and sociodemographic and clinical data. In each group of 39 subjects, LPR total and by quartiles (Q) and metrological and clinical data were evaluated. No differences were found in relation to total flexion and LPR extension. However, study by Q showed less movement in aLBP compared to axSpA and healthy subjects at the Lumbar level in Q2 (p = 0.001), Pelvis in Q3 and Q4 and Trunk in Q3 (p=