Individuals with Non-Specific Low Back Pain Use a Trunk Stiffening Strategy to Maintain Upright Posture

Authors

Stephanie L. Jones, University of VermontFollow
Sharon M. Henry, University of Vermont
Christine C. Raasch, Exponent Failure Analysis Associates, Inc.
Juvena R. Hitt, University of Vermont
Janice Y. Bunn, University of Vermont

Document Type

Article

Publication Date

2-1-2012

Publication Title

Journal of Electromyography and Kinesiology

Abstract

There is increasing evidence that individuals with non-specific low back pain (LBP) have altered movement coordination. However, the relationship of this neuromotor impairment to recurrent pain episodes is unknown. To assess coordination while minimizing the confounding influences of pain we characterized automatic postural responses to multi-directional support surface translations in individuals with a history of LBP who were not in an active episode of their pain. Twenty subjects with and 21 subjects without non-specific LBP stood on a platform that was translated unexpectedly in 12 directions. Net joint torques of the ankles, knees, hips, and trunk in the frontal and sagittal planes as well as surface electromyographs of 12 lower leg and trunk muscles were compared across perturbation directions to determine if individuals with LBP responded using a trunk stiffening strategy. Individuals with LBP demonstrated reduced peak trunk torques, and enhanced activation of the trunk and ankle muscle responses following perturbations. These results suggest that individuals with LBP use a strategy of trunk stiffening achieved through co-activation of trunk musculature, aided by enhanced distal responses, to respond to unexpected support surface perturbations. Notably, these neuromotor alterations persisted between active pain periods and could represent either movement patterns that have developed in response to pain or could reflect underlying impairments that may contribute to recurrent episodes of LBP. © 2011 Elsevier Ltd.

Keywords

Ankle strategy, Automatic postural response, Hip strategy, Joint torque, Postural control, Surface electromyography

Volume

22

Issue

1

First Page

13

Last Page

20

DOI

10.1016/j.jelekin.2011.10.006

ISSN

10506411

Rights

© 2011 Elsevier Ltd. All rights reserved.

Comments

Author’s submitted manuscript.

Recommended Citation

Jones, Stephanie L.; Henry, Sharon M.; Raasch, Christine C.; Hitt, Juvena R.; and Bunn, Janice Y., "Individuals with Non-Specific Low Back Pain Use a Trunk Stiffening Strategy to Maintain Upright Posture" (2012). Exercise and Sport Studies: Faculty Publications, Smith College, Northampton, MA.
https://scholarworks.smith.edu/ess_facpubs/6