The influence of intensity and duration of a painful conditioning stimulation on conditioned pain modulation in volunteers

104

Section: Effects Of Conditioning Intensity and Timesupporting

confidence: 90%

User‐independent assessment of conditioning pain modulation by cuff pressure algometry

Graven‐Nielsen

Izumi

Petersen

et al. 2016

104

“…() 4/10, and Graven‐Nielsen et al. () used variable pressures resulting in 3, 5 and 8/10, whilst a series of studies using the modified submaximal effort limit pain to ≤7/10 (Leffler et al., ; Tuveson et al., , , ; Razavi et al., ). Thus, it appears a minimum of 3/10 pain elicited by an occlusal cuff CS is required to significantly increase CPM magnitude.…”

Section: Discussionmentioning

confidence: 99%

“…A large portion of research on CPM paradigms has focussed on application of a thermal CS modality (Willer et al, 1984;Lautenbacher et al, 2002;Granot et al, 2008;Nir et al, 2011;Razavi et al, 2014). An alternative procedure involves application of an occlusion cuff.…”

Section: Introductionmentioning

confidence: 99%

Conditioned pain modulation is affected by occlusion cuff conditioning stimulus intensity, but not duration

Smith

Pedler

2017

Background: Various conditioned pain modulation (CPM) methodologies have been used to investigate diffuse noxious inhibitory control pain mechanisms in healthy and clinical populations. Occlusion cuff parameters have been poorly studied. We aimed to investigate whether occlusion cuff intensity and/or duration influenced CPM magnitudes. We also investigated the role of physical activity levels on CPM magnitude. Methods: Two studies were performed to investigate the role of intensity and duration of occlusion cuff conditioning stimulus on test stimulus (tibialis anterior pressure pain thresholds). In Study 1, conditioning stimulus intensity of 2/10 or 5/10 (duration <20 s) was evaluated using a paired-samples t-test. In Study 2, duration of 2/10 conditioning stimulus was 3 min. One-way repeated-measures ANOVA was used to investigate the effect of time (0, 1, 2 and 3 min) on CPM magnitude. Results: In Study 1, 27 healthy volunteers (mean AE SD: 24.9 years (AE4.5); eight female) demonstrated that an occlusion cuff applied to the upper arm eliciting 5/10 local pain resulted in a significant (mean AE SD: 17% AE 46%) increase in CPM magnitude, when compared to 2/10 intensity (À3% AE 38%, p = 0.026), whereas in Study 2, 25 healthy volunteers (22.5 years (AE2.7); 13 female) demonstrated that 3 min of 2/ 10 CS intensity did not result in a significant change in CPM (p = 0.21). There was no significant relationship between physical activity levels and CPM in either study (p > 0.22). Conclusions: This study demonstrated that an occlusion cuff of 5/10 conditioning stimulus intensity, when compared to 2/10, significantly increased CPM magnitude. Maintaining 2/10 conditioning stimulus for 3 min did not increase CPM magnitude. Significance: Dysfunctional conditioned pain modulation (CPM) has been associated with poor health outcomes. Various factors can influence CPM outcomes. The role of occlusion cuff conditioning stimulus intensity and duration has not been previously investigated. Intensity (5/10), but not duration of lower intensity (2/10) conditioning stimulus, affects CPM magnitude.94 Eur J Pain 22 (2018) 94--102

“…Pain thresholds are the most common outcome for CPM‐effects (Nir et al., ; Razavi et al., ; Zheng et al., ; Coppieters et al., ; Flood et al., , ; Naugle et al., ; Smith and Pedler, ) and both PDT and PTT can reliably assess CPM‐effects by means of the computerized pressure cuff (Graven‐Nielsen et al., ), albeit that within‐session reliability of PDT is higher compared to PTT (Imai et al., ). In this study, the CPM‐effects of the conditioning stimulus were analysed by the PDT (for PTT effects see Appendix ) from the test‐stimuli (Graven‐Nielsen et al., ).…”

Section: Methodsmentioning

confidence: 99%

Effects of repeated conditioning pain modulation in healthy volunteers

Hoegh

Petersen

Graven‐Nielsen

2018

Conditioning pain modulation can be assessed in 5-min intervals by cuff algometry with a fixed conditioning stimulus. Without applying conditioning stimuli the pain sensitivity of test-stimuli habituated. As a consequence, it can be speculated that the conditioning stimulus may negate the temporal habituation effects during repeated sessions, whereas this may not be the case for unconditioned stimuli. Applying both conditioned and unconditioned repeated test-stimuli may be a way to assess different parts of the pain modulatory system, and a model for measuring a netCPM-effect, which could indicate a balance between habituation and sensitization, is proposed.