Kinematics of the Lumbar Spine and Hip Joints in People with Persistent Low Back Pain during Sit to Stand and Stand to Sit Activities

Background: To our knowledge, no study has examined the kinematics of lumbopelvic-hip complex of individuals with chronic low back pain (CLBP) who had lumbar flexion+rotation (F+R) syndrome during sit to stand (SiToSt) and stand to sit (StToSi) activities. Thus, this study aimed to examine movement patterns of the lumbopelvic-hip complex in participants with CLBP classified into F+R syndrome subgroup. Methods: This was a cross sectional study. A 3-dimensional motion capture system was used to record movements of the lumbar spine and hips during SiToSt and StToSi. Participants were 20 patients with LBP classified in lumbar F+R subgroup, based on the movement impairment system model, and 20 asymptomatic individuals. The study was approved by Shahid Beheshti University of Medical Sciences (IR, SBMU.RETECH, and REC.1395.365). Results: Greater and significant lumbar flexion, with SiToSt, and lumbar extension, with StToSi, were observed in the patients. In addition, the patients exhibited a greater magnitude of lumbar rotation during SiToSt. No significant difference was observed between the 2 groups in hip motions. Conclusion: The patients with lumbar F+R syndrome tend to move their lumbopelvic region to a greater extent in sagittal and horizontal planes during SiToSt and StToSi compared with participants without low back pain.