Comparable effect of simulated side bending and side gliding positions on the direction and magnitude of lumbar disc hydration shift:in vivoMRI mechanistic study

Abstract

Objectives: To investigate the direction and magnitude of mechanical influence to the lumbar disc in side bending and side gliding positions by considering shift of disc hydration. Methods: Twenty asymptomatic subjects completed this study. Direction of the hydration shift (h), magnitude of the shift, and segmental lateral flexion and rotation angles from L1/L2 to L5/S1 during left side bend and side glide in lying were measured by magnetic resonance imaging (MRI) and compared using paired t-tests. Results: A significant difference (P,0.001) was detected in the segmental lateral flexion angle at L1/L2 between the side bending position (mean [SD], 5.1u [2.2u] left lateral flexion) and the side gliding position (mean [SD], 2.1u [2.7u] left lateral flexion). However, there was neither significant difference (P.0.05) in the lateral flexion angle at other segments nor rotation angles at each segment between the two lumbar positions. There was also no significant difference (P.0.05) in the h value and magnitude of the hydration shift between the two lumbar positions. The disc hydration generally shifted to the right in the left side bending and side gliding positions at all disc levels. Discussion: This is the first study to investigate mechanical influence to each lumbar disc in the side gliding position using the shift of disc hydration on axial MRI. The comparability in the direction and magnitude of the hydration shift in the side bending and side gliding positions indicates that the maneuver of side gliding can produce comparable ipsilateral mechanical influence to each lumbar disc in comparison to side bending.

Immediate alteration of the lumbar intervertebral foramen during the so-called osteopathic locking technique: A preliminary analysis on healthy subjects

“…On the other hand, some experimental studies demonstrated that combined motions usually occurred during axial rotation, inter alia, due to the facet gapping [19]. This condition produces 3D motion of the vertebra [20] and specific biomechanical features of the disc [21,22]. These biomechanical behaviors represent the basis of the socalled osteopathic manipulative locking technique (OMLT) which is designed to involve the intervertebral joint movements [14].…”