Can training to dissociate trunk and pelvic motion influence thorax-pelvis coordination and lumbar spine dynamic stability?

Background The large number of articulating joints within the spinal column provides an abundance of options to control its movement. However, the ability of individuals to consciously manipulate these movement options is poorly understood. Objectives To determine if short-term training can improve the ability to consciously dissociate motion between the pelvis and thorax during repetitive pelvic tilting movements. Design Cross-over design with young healthy individuals. Method Seventeen participants performed trials consisting of 35 continuous lift/lowers followed by 35 continuous anterior/posterior pelvic tilts while spine kinematics were recorded. Participants then underwent a 20-minute training protocol designed to improve the control of pelvic motion and in particular the dissociation of pelvic and trunk motion. Post-training, the continuous pelvic tilt and lift/lower trials were repeated. Thorax-pelvis movement coordination was analyzed via vector coding and lumbar spine local dynamic stability was analyzed via Lyapunov exponents. Participants were grouped as being either high or low skill movers based on their ability to perform the pre-training pelvic tilt movements. Results The low skill movement group demonstrated statistically significant increases in the time spent using in-phase pelvic dominant (p = 0.028) and anti-phase pelvic dominant (p = 0.043) coordination patterns during the pelvic tilt movements after the completion of the training protocol. The high skill movement group showed no differences in their movement patterns post-training. Conclusions Short-term training, targeted on improving the ability to dissociate pelvic from thorax motion, had a beneficial effect on the group of individuals who initially lacked skill performing the pelvic tilting task.