Functional data analysis of the full-body kinematics during a step-up task in subjects with and without low back pain: A cross-sectional study.

This study aims to explore comprehensive kinematic patterns of all body joints utilizing a nonlinear functional data analysis (FDA) approach during a step-up task in patients with nonspecific chronic low back pain (NSCLBP). The kinematics of the trunk, pelvis, and upper- and lower-extremities during step-up exercises were assessed in NSCLBP (N = 23) and control (N = 22) groups using a Motion Analysis System. FDA was employed to compare movement-patterns of 15 segments between two groups.