Cross-spectral analysis quantifies the segmental coordination in unstable sitting

Abstract

Abstract Introduction: Low back pain(LBP) affects many individuals and is known to be associated with impaired trunk control. While LBP can be associated by treating underlying trunk impairments, a better understandinf of the mechanistic origin of the disorder is required. Trunk control has been commonly studied via an unstable sitting paradigm. Knowledge on how the base of support and body segments work together to complete the unstable sitting task, and how this is modified in individuals with LBP, could be utilized when designing interventions for this population. Our obiective was to characterize the segmental coordination in non-impaired unstable sitting as elicited via a wobble board(WB) paradigm. Methods: WB, pelvis, and trunk motion were recorded in fifteen non-disabled participants sitting on a wobble board. We used cross-spectral analysis to quantify the coordination of the anterior-posterior angular kinematics of the wobble board, pelvis, and trunk. Results: During unstable sitting, the motion of the pelvis was followed by that of the trunk(one-eighth-cycle delay) and wobble board(half-cyclw delay) at frequenties between 1 and 2 Hz. Conclusion: Future work should utilize the knowledge gained in this study when creating rehabilitation interventions for individuals with LBP.