Article

It has been hypothesized that individuals with low back pain (LBP) will have
higher trunk muscle activity during gait, in an attempt to limit spine motion,
and that this "guarding strategy" may be influenced by the person's psychological
response to pain. This study investigated whether the amplitude of trunk muscle
activation differs between persons with chronic LBP and healthy individuals
during walking, and whether changes in muscle activation were related to pain
catastrophizing. Thirty persons with chronic non-specific LBP, stratified into 2
groups of high (HLBP) and low (LLBP) pain catastrophizing, were contrasted with a
control group of 15 healthy individuals during walking on a treadmill at a
self-selected speed. Surface electromyographic (EMG) data were recorded from 10
trunk muscles. The effects of Group and gait Sub-phase on EMG activation
amplitudes were assessed. The HLBP group exhibited higher activation of certain
muscles throughout the gait cycle, and reduced variability of others at specific
sub-phases of gait. A significant correlation was found between activation
amplitude and pain catastrophizing in most muscles, when controlling for gait
speed and pain intensity. These data indicate that altered trunk muscle
activation is present in some patients with LBP during walking, but does not
represent a universal increase in activation for all muscles. This altered
neuromotor control is, however, more strongly associated with pain
catastrophizing than with pain intensity, and appears to represent a
non-functional, maladaptive behavior, as it alters the normal, phasic pattern of
activation in certain trunk muscles.
CI - Copyright (c) 2016 Elsevier B.V. All rights reserved.

Langue : ANGLAIS