Does experimentally induced pain-related fear influence central and peripheral movement preparation in healthy people and patients with low back pain?

Abstract

Nonspecific chronic low back pain (CLBP) is a multifactorial disorder. Pain-related fear and altered movement preparation are considered to be key factors in the chronification process. Interactions between both have been hypothesized, but studies examining the influence of situational fear on movement preparation in low back pain (LBP) are wanting, as well as studies differentiating between recurrent LBP (RLBP) and CLBP. Therefore, this study examined whether experimentally induced pain-related fear influences movement preparation. In healthy controls (n = 32), RLBP (n = 31) and CLBP (n = 30) patients central and peripheral measures of movement preparation were assessed by concurrently measuring trunk muscle anticipatory postural adjustments (APA) with electromyography and contingent negative variation with EEG during performance of rapid arm movements. Two conditions were compared, one without (no fear) and one with (fear) possibility of painful stimulation to the back during rapid arm movements. Visual analogue scales were used to assess pain-related expectations/fear in both conditions. The experimentally induced fear of pain during movement performance led to an increase in contingent negative variation amplitude, which was similar in all 3 groups. Concerning APAs, no effects of fear were found, but group differences with generally delayed APAs in CLBP compared with controls and RLBP patients were evident. These results suggest that with fear, an attentional redirection towards more conscious central movement preparation strategies occurs. Furthermore, differences in movement preparation in patients with RLBP and CLBP exist, which could explain why patients with RLBP have more recovery capabilities than patients with CLBP.

A task‐relevant experimental pain model to target motor adaptation

“…Hence, our approach provides an important advantage over brief trains (i.e. 100 ms) of square wave electrical stimuli that induce EMG artefacts limiting the analysis of neuromuscular activation to periods before or after the stimuli (Moseley et al 2004;Moseley & Hodges, 2005;Tucker et al 2012;Schouppe et al 2020). Despite this key methodological advance for EMG recordings during painful electrical stimuli, careful consideration of the characteristics of the EMG amplifier, especially gain and input range of the A/D board, is needed to avoid its saturation during data acquisition (we excluded data from a participant for this reason).…”

“…Electrical stimuli can activate nociceptors in non-muscular tissues (Koga et al 2005;Maffiuletti et al 2008), with stimulus intensity modulating pain perception (Laursen et al 1997). Brief trains of electrical stimuli (square waves; 100-200 ms burst of 200-1000 μs impulses delivered at ∼50-200 Hz) enable the characterization of altered neuromuscular activation in anticipation or in response to motion-induced pain (Moseley et al 2004;Moseley & Hodges, 2005;Tucker et al 2012;Schouppe et al 2020). However, repeated application of electrical painful stimuli may lead to habituation in pain perception (Ernst et al 1986;Eitner et al 2018); hence painful electrical stimulation has mostly been used to reproduce phasic pain (Zedka et al 1999;Moseley et al 2004;Moseley & Hodges, 2005;Tucker et al 2012;Schouppe et al 2020).…”

“…Brief trains of electrical stimuli (square waves; 100-200 ms burst of 200-1000 μs impulses delivered at ∼50-200 Hz) enable the characterization of altered neuromuscular activation in anticipation or in response to motion-induced pain (Moseley et al 2004;Moseley & Hodges, 2005;Tucker et al 2012;Schouppe et al 2020). However, repeated application of electrical painful stimuli may lead to habituation in pain perception (Ernst et al 1986;Eitner et al 2018); hence painful electrical stimulation has mostly been used to reproduce phasic pain (Zedka et al 1999;Moseley et al 2004;Moseley & Hodges, 2005;Tucker et al 2012;Schouppe et al 2020). In addition, electrical stimuli create artefacts in electromyographic (EMG) recordings, preventing the quantification of muscle activation during the application of the painful stimuli (Zedka et al 1999;Moseley et al 2004;Moseley & Hodges, 2005;Tucker et al 2012;Schouppe et al 2020).…”

Electrical Properties of Lumbar Paraspinal Muscles in Young Adults With and Without Chronic Low Back Pain Based on Electrical Impedance Myography: A Cross-Sectional Study

“…The inclusion criteria for the HC group were the absence of LBP in the preceding 2 years and no history of other diseases ( 28 ). The exclusion criteria for HCs were age outside of the specified range, pregnancy even if the person who matched the inclusion criteria, or history of other diseases or surgery.…”

Different Electrical Properties of Paraspinal Muscle in Young Adults With Non-specific Chronic Low Back Pain and Healthy Individuals by Electrical Impedance Myography: A Cross-sectional Study

“…For the HC group, the inclusion criteria was participants without low back pain in 2 years and had no history with diseases were included [18]. Meanwhile, those out of the age range, pregnant, and had history with other diseases or surgery were excluded from the story.…”