scholarly journals Comparison of Thermal and Electrical Modalities in the Assessment of Temporal Summation of Pain and Conditioned Pain Modulation

2021 ◽  
Vol 2 ◽  
Author(s):  
Monica Sean ◽  
Alexia Coulombe-Lévêque ◽  
Martine Bordeleau ◽  
Matthieu Vincenot ◽  
Louis Gendron ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Temporal Summation ◽  
Cold Pressor Test ◽  
Conditioning Stimulus ◽  
Cold Pressor ◽  
Pain Modulation ◽  
Conditioned Pain Modulation ◽  
Electrical Nerve Stimulation ◽  
Clinical Assessments ◽  
Healthy Participants

Temporal summation of pain (TSP) and conditioned pain modulation (CPM) can be measured using a thermode and a cold pressor test (CPT). Unfortunately, these tools are complex, expensive, and are ill-suited for routine clinical assessments. Building on the results from an exploratory study that attempted to use transcutaneous electrical nerve stimulation (TENS) to measure CPM and TSP, the present study assesses whether a “new” TENS protocol can be used instead of the thermode and CPT to measure CPM and TSP. The objective of this study was to compare the thermode/CPT protocol with the new TENS protocol, by (1) measuring the association between the TSP evoked by the two protocols; (2) measuring the association between the CPM evoked by the two protocols; and by (3) assessing whether the two protocols successfully trigger TSP and CPM in a similar number of participants. We assessed TSP and CPM in 50 healthy participants, using our new TENS protocol and a thermode/CPT protocol (repeated measures and randomized order). In the TENS protocol, both the test stimulus (TS) and the conditioning stimulus (CS) were delivered using TENS; in the thermode/CPT protocol, the TS was delivered using a thermode and the CS consisted of a CPT. There was no association between the response evoked by the two protocols, neither for TSP nor for CPM. The number of participants showing TSP [49 with TENS and 29 with thermode (p < 0.001)] and CPM [16 with TENS and 30 with thermode (p = 0.01)] was different in both protocols. Our results suggest that response to one modality does not predict response to the other; as such, TENS cannot be used instead of a thermode/CPT protocol to assess TSP and CPM without significantly affecting the results. Moreover, while at first glance it appears that TENS is more effective than the thermode/CPT protocol to induce TSP, but less so to induce CPM, these results should be interpreted carefully. Indeed, TSP and CPM response appear to be modality-dependent as opposed to an absolute phenomenon, and the two protocols may tap into entirely different mechanisms, especially in the case of TSP.

scholarly journals Reference values of conditioned pain modulation

2019 ◽  
Vol 19 (2) ◽  
pp. 279-286
Author(s):  
Jürg Schliessbach ◽  
Christian Lütolf ◽  
Konrad Streitberger ◽  
Pasquale Scaramozzino ◽  
Lars Arendt-Nielsen ◽  
...  
Keyword(s):  
Reference Values ◽  
Cold Pressor Test ◽  
Conditioning Stimulus ◽  
Cold Pressor ◽  
Pain Modulation ◽  
Conditioned Pain Modulation ◽  
Abnormal Finding ◽  
Withdrawal Reflex ◽  
Endogenous Pain Modulation ◽  
Electrical Stimuli

Abstract Background and aims Endogenous pain modulation can be studied in humans by conditioned pain modulation (CPM): pain induced by a test stimulus is attenuated by a distantly applied noxious conditioning stimulus. The detection of impaired CPM in individual patients is of potential importance to understand the pathophysiology and predict outcomes. However, it requires the availability of reference values. Methods We determined reference values of CPM in 146 pain-free subjects. Pressure and electrical stimulation were the test stimuli. For electrical stimuli, we recorded both pain threshold and threshold for the nociceptive withdrawal reflex. Cold pressor test was the conditioning stimulus. The 5th, 10th and 25th percentiles for the three tests were computed by quantile regression analyses. Results The average thresholds increased after the conditioning stimulus for all three tests. However, a subset of subjects displayed a decrease in thresholds during the conditioning stimulus. This produced negative values for most of the computed percentiles. Conclusions This study determined percentile reference values of CPM that can be used to better phenotype patients for clinical and research purposes. The negative value of percentiles suggests that a slightly negative CPM effect can be observed in pain-free volunteers. Implications Pain facilitation rather than inhibition during the conditioning stimulus occurs in some pain-free volunteers and may not necessarily represent an abnormal finding.

Fixed or adapted conditioning intensity for repeated conditioned pain modulation

2017 ◽  
Vol 16 (1) ◽  
pp. 176-176
Author(s):  
M. Hoegh ◽  
K.K. Petersen ◽  
T. Graven-Nielsen
Keyword(s):  
Pain Intensity ◽  
Repeated Measures ◽  
Rating Scale ◽  
Cuff Pressure ◽  
Detection Threshold ◽  
Conditioning Stimulus ◽  
Pain Modulation ◽  
Pain Tolerance ◽  
Conditioned Pain Modulation ◽  
The Difference

Abstract Aims Conditioned pain modulation (CPM) is used to assess descending pain modulation through a test stimulation (TS) and a conditioning stimulation (CS). Due to potential carry-over effects, sequential CPM paradigms might alter the intensity of the CS, which potentially can alter the CPM-effect. This study aimed to investigate the difference between a fixed and adaptive CS intensity on CPM-effect. Methods On the dominant leg of 20 healthy subjects the cuff pressure detection threshold (PDT) was recorded as TS and the pain tolerance threshold (PTT) was assessed on the non-dominant leg for estimating the CS. The difference in PDT before and during CS defined the CPM-effect. The CPM-effect was assessed four times using a CS with intensities of 70% of baseline PTT (fixed) or 70% of PTT measured throughout the session (adaptive). Pain intensity of the conditioning stimulus was assessed on a numeric rating scale (NRS). Data were analyzed with repeated-measures ANOVA. Results No difference was found comparing the four PDTs assessed before CSs for the fixed and the adaptive paradigms. The CS pressure intensity for the adaptive paradigm was increasing during the four repeated assessments (P < 0.01). The pain intensity was similar during the fixed (NRS: 5.8±0.5) and the adjusted paradigm (NRS: 6.0±0.4). The CPM-effect was higher using the fixed condition compared with the adaptive condition (P < 0.05). Conclusions The current study found that sequential CPM paradigms using a fixed conditioning stimulus produced an increased CPM-effect compared with adaptive and increasing conditioning intensities.

Effects of conditioned pain modulation on the withdrawal pattern to nociceptive stimulation in humans – Preliminary results

2017 ◽  
Vol 16 (1) ◽  
pp. 176-177
Author(s):  
F.A. Jure ◽  
F.G. Arguissain ◽  
J.A. Biurrun Manresa ◽  
O.K. Andersen
Keyword(s):  
Cold Water ◽  
Cold Pressor Test ◽  
Cold Pressor ◽  
Biceps Femoris ◽  
Pain Modulation ◽  
Wilcoxon Test ◽  
Conditioned Pain Modulation ◽  
Stimulus Interval ◽  
Biceps Femoris Muscle ◽  
Femoris Muscle

AbstractAimsConditioned pain modulation (CPM) is a paradigm employed to assess descending control of spinal nociception. Previous studies have shown that CPM affects the nociceptive withdrawal reflex (NWR) threshold (RTh), typically assessed in one muscle. However, the NWR activates not one but a group of synergistic muscles, which are recruited by common neural commands to achieve the limb withdrawal. In this regard, synergy analysis can provide the minimum coordinated recruitment of groups of muscles with specific activation balances that describe a movement. The aim was to assess how CPM modulate the global withdrawal strategy of the lower limb expressed by synergy analysis.MethodsSixteen healthy subjects received electrical stimulation in the arch of the foot at 2 × RTh intensity assessed at the biceps femoris muscle, to elicit the NWR at three time points: before, during and after immersion of the hand in cold water at 2.6 ± 0.4° (cold pressor test, CPT) to trigger CPM. Electromyographic signals (EMG) were recorded from 2 distal muscles (tibialis anterior, soleus) and 2 proximal muscles (biceps femoris, rectus femoris). Muscle synergies were identified by a non-negative matrix factorization algorithm for the EMG envelope in the 60–180 ms post-stimulus interval. Data were analyzed by a point-by-point Wilcoxon test using a permutation strategy.ResultsThe overall withdrawal pattern was explained by two main synergies (Syn1 and Syn2). Syn1 mainly contributes to EMG of distal muscles, whereas Syn2 contributes to EMG of proximal muscles. During CPT, the magnitude of Syn2 was reduced in the 160–180ms post-stimulus interval (p < 0.05), whereas no changes were found for Syn1.ConclusionsAt least two synergies are required to explain the NWR. Furthermore, results suggest that CPM might differentially affect proximal and distal muscles. Further analysis is needed to provide additional information about the behavior of the individual muscles.

scholarly journals Reliability of the Conditioned Pain Modulation Paradigm to Assess Endogenous Inhibitory Pain Pathways

2012 ◽  
Vol 17 (2) ◽  
pp. 98-102 ◽  
Author(s):  
Gwyn N Lewis ◽  
Heales Luke ◽  
David A Rice ◽  
Keith Rome ◽  
Peter J McNair
Keyword(s):  
Pain Threshold ◽  
Intraclass Correlation ◽  
Cold Pressor Test ◽  
Pressure Pain Threshold ◽  
Cold Pressor ◽  
Pain Modulation ◽  
Conditioned Pain Modulation ◽  
Pressure Pain ◽  
Pressor Test ◽  
Conditioning Stimuli

BACKGROUND: Conditioned pain modulation paradigms are often used to assess the diffuse noxious inhibitory control (DNIC) system. DNICs provide one of the main supraspinal pain inhibitory pathways and are impaired in several chronic pain populations. Only one previous study has examined the psychometric properties of the conditioned pain modulation technique and this study did not evaluate intersession reliability.OBJECTIVES: To evaluate and compare the intra- and intersession reliability of two conditioned pain modulation paradigms using different conditioning stimuli, and to determine the time course of conditioned pain inhibition following stimulus removal.METHODS: An electronic pressure transducer was used to determine the pressure-pain threshold at the knee during painful conditioning of the opposite hand using the ischemic arm test and the cold pressor test. Assessments were completed twice on one day and repeated once approximately three days later.RESULTS: The two conditioning stimuli resulted in a similar increase in the pressure-pain threshold at the knee, reflecting presumed activation of the DNIC system. Intrasession intraclass correlation coefficients for the cold pressor (0.85) and ischemic arm tests (0.75) were excellent. The intersession intraclass correlation coefficient for the cold pressor test was good (0.66) but was poor for the ischemic arm test (−0.4). Inhibition of the pressure-pain threshold remained significant at 10 min following conditioning, but returned to baseline by 15 min.CONCLUSIONS: Within-session reliability of DNIC assessment using conditioned pain modulation paradigms was excellent, but the applicability of assessing pain modulation over multiple sessions was influenced by the conditioning stimulus. The cold pressor test was the superior technique.

scholarly journals Total sleep deprivation increases pain sensitivity, impairs conditioned pain modulation and facilitates temporal summation of pain in healthy participants

PLoS ONE ◽  
2019 ◽  
Vol 14 (12) ◽  
pp. e0225849 ◽  
Author(s):  
Alexander Torp Staffe ◽  
Mathias Winther Bech ◽  
Sara Louise Kjær Clemmensen ◽  
Henriette Tranberg Nielsen ◽  
Dennis Boye Larsen ◽  
...  
Keyword(s):  
Sleep Deprivation ◽  
Pain Sensitivity ◽  
Temporal Summation ◽  
Pain Modulation ◽  
Conditioned Pain Modulation ◽  
Total Sleep Deprivation ◽  
Healthy Participants

scholarly journals Offset analgesia is not affected by cold pressor induced analgesia

2018 ◽  
Vol 18 (4) ◽  
pp. 695-701 ◽  
Author(s):  
Thomas Dahl Nissen ◽  
Carsten Dahl Mørch ◽  
Lars Arendt-Nielsen ◽  
Asbjørn Mohr Drewes ◽  
Anne Estrup Olesen
Keyword(s):  
Pain Intensity ◽  
Assessment Tool ◽  
Cold Pressor Test ◽  
Cold Pressor ◽  
Pain Modulation ◽  
Descending Inhibition ◽  
Cold Pain ◽  
Pressor Test ◽  
Endogenous Pain Modulation ◽  
Healthy Participants

Abstract Background and aims Offset analgesia (OA) is a pain modulating mechanism described as a disproportionately large decrease in pain intensity evoked by a minor decrease in stimulus intensity. Precise mechanisms of OA are still not elucidated and studies are needed to evaluate factors modulating OA. The aim of this study was to investigate OA before and during tonic cold pain (thought to induce descending inhibition), in a group of healthy volunteers. Methods A randomized, crossover study was performed in 17 healthy participants (8 males and 9 females). The OA paradigm lasted 35 s and was induced by the traditional method using thermal stimulation applied to the forearm. A constant control heat stimulus (CTL) paradigm was used as control to assess adaptation. Pain intensity was assessed continuously. For induction of tonic cold pain, the participants immersed their hand into 2°C water for 2 min. After 1 min and 25 s, the heat stimulation (OA or CTL paradigm) was repeated to assess the modulatory effect of the cold pressor test. Results It was possible to induce OA both before and during the cold pressor test. Tonic cold pain modulated the peak pain reported during both the OA (p=0.015) and CTL paradigms (p=0.001) reflecting endogenous pain modulation. However, the magnitude of OA was not modulated by tonic cold pain (p>0.05). Conclusions The offset analgesia magnitude was not modulated by simultaneously tonic cold pain, thought to reflect another endogenous pain modulation mechanism. Implications Neither offset analgesia magnitude nor adaptation were modulated by cold pressor induced endogenous analgesia. This could be explained by the fact, that offset analgesia was already at maximum in healthy participants. Hence, offset analgesia may not be a suitable assessment tool to investigate modulation induced by experimental methods or pharmacology in healthy participants.

The Effect of Conditioned Pain Modulation on Tonic Heat Pain Assessed Using Participant-Controlled Temperature

Pain Medicine ◽  
2020 ◽  
Vol 21 (11) ◽  
pp. 2839-2849
Author(s):  
Laura Sirucek ◽  
Catherine Ruth Jutzeler ◽  
Jan Rosner ◽  
Petra Schweinhardt ◽  
Armin Curt ◽  
...  
Keyword(s):  
Test Stimulus ◽  
Temporal Summation ◽  
Pressure Pain Threshold ◽  
Conditioning Stimulus ◽  
Pain Modulation ◽  
Conditioned Pain Modulation ◽  
Heat Pain ◽  
Pressure Pain ◽  
Withdrawal Reflex ◽  
Pressure Pain Thresholds

Abstract Objective Descending pain modulation can be experimentally assessed by way of testing conditioned pain modulation. The application of tonic heat as a test stimulus in such paradigms offers the possibility of observing dynamic pain responses, such as adaptation and temporal summation of pain. Here we investigated conditioned pain modulation effects on tonic heat employing participant-controlled temperature, an alternative tonic heat pain assessment. Changes in pain perception are thereby represented by temperature adjustments performed by the participant, uncoupling this approach from direct pain ratings. Participant-controlled temperature has emerged as a reliable and sex-independent measure of tonic heat. Methods Thirty healthy subjects underwent a sequential conditioned pain modulation paradigm, in which a cold water bath was applied as the conditioning stimulus and tonic heat as a test stimulus. Subjects were instructed to change the temperature of the thermode in response to variations in perception to tonic heat in order to maintain their initial rating over a two-minute period. Two additional test stimuli (i.e., lower limb noxious withdrawal reflex and pressure pain threshold) were included as positive controls for conditioned pain modulation effects. Results Participant-controlled temperature revealed conditioned pain modulation effects on temporal summation of pain (P = 0.01). Increased noxious withdrawal reflex thresholds (P = 0.004) and pressure pain thresholds (P &lt; 0.001) in response to conditioning also confirmed inhibitory conditioned pain modulation effects. Conclusions The measured interaction between conditioned pain modulation and temporal summation of pain supports the participant-controlled temperature approach as a promising method to explore dynamic inhibitory and facilitatory pain processes previously undetected by rating-based approaches.

Exercise does not produce hypoalgesia when performed immediately after a painful stimulus

2018 ◽  
Vol 18 (2) ◽  
pp. 311-320 ◽  
Author(s):  
Hannah Gajsar ◽  
Katharina Nahrwold ◽  
Christina Titze ◽  
Monika I. Hasenbring ◽  
Henrik B. Vaegter
Keyword(s):  
Chronic Pain ◽  
Repeated Measures ◽  
Cold Pressor Test ◽  
Cold Pressor ◽  
Pain Modulation ◽  
Control Session ◽  
Target Heart Rate ◽  
Inhibitory System ◽  
Cold Pressor Task ◽  
Pressure Pain Thresholds

Abstract Background and aims: Exercise-induced hypoalgesia (EIH) and conditioned pain modulation (CPM) are assumed to reflect descending pain inhibition. Potential interactions between EIH and CPM may be important in the therapy of chronic pain, as reduced CPM and increased pain after exercise are frequently observed. This study compared the EIH response after CPM was activated using a cold pressor task with the EIH response after a control condition. Methods: Thirty-one participants (age: 27.7±9.8; 15 female) completed two sessions: a cold pressor task (CPT) session, i.e. testing EIH with preceding CPM activation induced using a 2 min CPT at approximately 2°C, and a control session, i.e. testing EIH after a control condition (2 min of quiet rest). EIH was induced using a 15 min bicycling exercise at a target heart rate corresponding to 75% VO2 max. Repeated measures ANOVAs on pressure pain thresholds (PPTs) at the hand, back and leg were used to determine the effects of exercise after the cold pressor test and control condition. Furthermore, correlations between CPM and EIH, in the CPT session as well as control session, were calculated at each assessment site. Results: A significant time x condition interaction (F(1, 30)=43.61, p<0.001, partial η2=0.59), with Bonferroni-corrected post-hoc t-tests showed that PPTs increased after exercise in the control session (p<0.001), but not in the CPT session (p=0.125). Furthermore, there was a small positive correlation of EIH in the control session and CPM at the hand (r=0.37, p=0.043). There was a moderate negative correlation of EIH in the CPT session and CPM at the hand (r=−0.50, p=0.004), and smaller negative correlations at the back (r=−0.37, p=0.036) and at the leg (r=−0.35, p=0.054). Conclusions: Attenuated EIH after the CPM activation in comparison to a control condition suggests that EIH and CPM may share underlying pain inhibitory mechanisms on a systemic level. This assumption is further supported by the finding of small to moderate significant correlations between EIH and CPM at the hand. The attenuated EIH response furthermore suggests that these mechanisms are exhaustible, i.e. that its effects decline after a certain amount of inhibition. Implications: In patients with chronic pain, assessing the current capacity of the descending pain inhibitory system – as indicated by the CPM response – may aid to make better predictions about how patients will respond to exercise with respect to acute pain reduction.

Sign in / Sign up

Export Citation Format

Share Document