Low back pain leads to a protective action of pain on dynamic postural stability

ABSTRACT

Low back pain (LBP) is a painful manifestation in the lower part of the spine which causes disabilities changing the sensitivity of sensory neurons resulting in weakness of postural muscles interfering with the balance. It is not already clear if LBP people’s muscle changes affect the centre of pressure (CoP) recovery in challenging stance perturbations. The aim of this study was to identify differences in the muscle reactions of people with and without LBP to control CoP in challenging stance perturbations. We applied low (Vel1) and high (Vel2) magnitude stance perturbation by a movable platform and evaluated (a) the magnitude and latency time of trunk and lower limb muscle activation, (b) and the displacement and the latency time of the first CoP peak. The latency of trunk and hip muscle activation on Vel2 was lower for LBP group. The CoP latency and displacement did not change between groups and velocities indicating that the muscles took the same time to overcome the external forces. In conclusion, the maintenance of CoP latency at both velocities was not affected on Vel2, suggesting that such alterations have protective action and preservation of the pain on the LPB group in challenging stance perturbations.

KEYWORDS:

• Low back pain
• balance perturbation
• muscle latency time
• pain protection

Acknowledgments

J.F.B. and I.C.V. would like to thanks CAPES and C.P. and R.O.M. to CNPq for their master and PhD fellowship.

Declarations of interest

The authors report no conflict of interest.

Human Research Ethics Committee

The authors declared that written patient consent, was obtained, and that the research was approved by the local Human Research Ethics Committee (N°620.735), in consonance with the Declaration of Helsinki.

Disclosure of potential conflicts of interest

No potential conflict of interest was reported by the author(s).