Trunk and pelvic coordination at various walking speeds during an anterior load carriage task in subjects with and without chronic low back pain.

[Purpose] This study compared the coordination patterns of the trunk and pelvis in the transverse plane between healthy subjects and patients with chronic low back pain during an anterior load carriage task at various walking speeds. [Subjects] Ten healthy subjects and 10 patients with chronic low back pain performed an anterior carriage task with a load of 10% body weight at walking speeds of 3.5, 4.5, or 5.5 km/h. [Methods] The trunk and pelvic kinematics were measured by using a motion analysis system. During the anterior carriage task, the continuous relative phase differed significantly between groups with respect to walking speed. [Results] The continuous relative phase was more anti-phase in the chronic low back pain group than the control group. The inter-group continuous relative phase pattern was affected by walking at 5.5 km/h. [Conclusion] Compared to controls, subjects with chronic low back pain are unable to establish an in-phase between the trunk and pelvis from walking at 3.5 to 5.5 km/h during an anterior carriage task.