Authors: Geoffrey Desmoulin, Theodore Milner
Publication: Canadian Acoustics, Volume 35, Issue 2, Pages 61-68
School of Kinesiology-Simon Fraser University
The feasibility of estimating lumbar mechanics in-vivo was evaluated using ultrasound imaging. Images were obtained while subjects were seated, with the pelvis fixed, and pulled on an anchored cable by isometrically contracting trunk muscles at different force levels. Linear regression analysis was used to identify ultrasound measurements which were correlated with trunk force. Results suggest that ultrasound is more suitable for estimating lumbar mechanics during lateral flexion than extension of the trunk. A linear trend was found between changes in thickness of some muscles and trunk force, which could provide an alternative to invasive intramuscular electrodes for measuring the activity of non-superficial muscles. A significant limitation, however, is that the magnitude of the changes were frequently very close to the ultrasound resolution.