Neuromuscular adaptations to experimentally induced pain in the lumbar region: systematic review and meta-analysis

Abstract

Experimental pain models are frequently used to understand the influence of pain on the control of human movement. In this systematic review, we assessed the effects of experimentally induced pain in the lumbar region of healthy individuals on trunk muscle activity and spine kinematics. Databases were searched from inception up to January 31, 2022. In total, 26 studies using either hypertonic saline injection (n 5 19), heat thermal stimulation (n 5 3), nociceptive electrical stimulation (n 5 3), or capsaicin (n 5 1) were included. The identified adaptations were task dependent, and their heterogeneity was partially explained by the experimental pain model adopted. Meta-analyses revealed an increase of erector spinae activity (standardized mean difference 5 0.71, 95% confidence interval [CI] 5 0.22-1.19) during full trunk flexion and delayed onset of transversus abdominis to postural perturbation tasks (mean difference 5 25.2 ms, 95% CI 5 4.09-46.30) in the presence of pain. Low quality of evidence supported an increase in the activity of the superficial lumbar muscles during locomotion and during voluntary trunk movements during painful conditions. By contrast, activity of erector spinae, deep multifidus, and transversus abdominis was reduced during postural perturbation tasks. Reduced range of motion of the lumbar spine in the presence of pain was supported by low quality of evidence. Given the agreement between our findings and the adaptations observed in clinical populations, the use of experimental pain models may help to better understand the mechanisms underlying motor adaptations to low back pain.

Pain-sensorimotor interactions: New perspectives and a new model

“…There have been many wide-ranging systematic or narrative reviews addressing one or more of these aspects (e.g. ( Andersen, 2007 , Bank et al, 2013 , Wager et al, 2013 , Hodges and Smeets, 2015 , Burns et al, 2016 , Chang et al, 2018 , van der Miesen et al, 2019 , Falla and Gallina, 2020 , Merkle et al, 2020 , Falla et al, 2021 , Sanderson et al, 2021 , Devecchi et al, 2023 , Graven-Nielsen and Arendt-Nielsen, 2008 ) and some findings particularly relevant to this present review are highlighted below.…”

The Role of Back Muscle Dysfunctions in Chronic Low Back Pain: State-of-the-Art and Clinical Implications

“…In the studies that do report differences in erector spinae reaction time, they are typically delayed [18,19]. Although these data appear to suggest some compromise in the activation of back muscles (which implies suboptimal control) [12], there are also data that suggest excessive recruitment of back muscles in response to experimental pain [44] and in individuals with chronic back pain during functional tasks [12,45], especially in those with unhelpful beliefs [46,47]. Increased activation appears to more consistently involve the more superficial erector spinae than deep (e.g., multifidus) muscles [12].…”