STUDIES ON PAIN: THE PHENOMENON OF SENSORY ‘EXTINCTION’ AND ITS RELATION TO PAIN THRESHOLD, PAIN INTENSITY AND PAIN PERCEPTION

Purpose: To determine changes in orofacial pain perception in community-based children by assessing the pressure pain threshold (PPT) with an algometer and pain intensity by manual palpation (MP). Methods: A total of 100 children from the community aged 7 to 12 years were assessed. Thirty-eight children reported pain in the orofacial region. Of these children,10 reported joint pain (GJ), 12 reported joint and muscle pain(GJMM), 5 reported muscle pain (GMM), 11 reported pain during mastication(GMAST), and 62 reported no pain. An ANOVA (p<0.05) was used to determine the differences in pain intensity and PPT among groups. Results: Significantly higher pain intensity upon MP was observed for the temporalis muscle in the GJMM, GMAST and GJ groups compared to the remaining groups. The PPT values were significantly lower in the masseter, temporalis muscles, TMJ and thenar region in the GJMM group compared to the other groups. Conclusion: MP more accurately differentiated symptomatic subjects from symptom-free TMD subjects, and PPT values were more sensitive to the discrimination of pain in the orofacial sites assessed. In addition, the changes in perception at a larger number of sites among children reporting mixed pain may suggest the presence of a possible mechanism of central sensitization.

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Reduction in Pain Sensitivity from Pharmacological Elevation of Blood Pressure in Persons with Chronically Low Blood Pressure

Journal of Psychophysiology ◽

10.1027/0269-8803.23.3.104 ◽

2009 ◽

Vol 23 (3) ◽

pp. 104-112 ◽

Cited By ~ 12

Author(s):

Stefan Duschek ◽

Heike Heiss ◽

Boriana Buechner ◽

Rainer Schandry

Keyword(s):

Blood Pressure ◽

Heart Rate ◽

Pain Sensitivity ◽

Pain Threshold ◽

Pain Perception ◽

Drug Effects ◽

Pressure Effects ◽

Double Blind ◽

Low Blood Pressure ◽

Present Trial

Recent studies have revealed evidence for increased pain sensitivity in individuals with chronically low blood pressure. The present trial explored whether pain sensitivity can be reduced by pharmacological elevation of blood pressure. Effects of the sympathomimetic midodrine on threshold and tolerance to heat pain were examined in 52 hypotensive persons (mean blood pressure 96/61 mmHg) based on a randomized, placebo-controlled, double-blind design. Heat stimuli were applied to the forearm via a contact thermode. Confounding of drug effects on pain perception with changes in skin temperature, temperature sensitivity, and mood were statistically controlled for. Compared to placebo, higher pain threshold and tolerance, increased blood pressure, as well as reduced heart rate were observed under the sympathomimetic condition. Increases in systolic blood pressure between points of measurement correlated positively with increases in pain threshold and tolerance, and decreases in heart rate were associated with increases in pain threshold. The findings underline the causal role of hypotension in the augmented pain sensitivity related to this condition. Pain reduction as a function of heart rate decrease suggests involvement of a baroreceptor-related mechanism in the pain attrition. The increased proneness of persons with chronic hypotension toward clinical pain is discussed.

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Pain perception in chronic knee osteoarthritis with varying levels of pain inhibitory control: an exploratory study

Scandinavian Journal of Pain ◽

10.1515/sjpain-2020-0016 ◽

2020 ◽

Vol 20 (4) ◽

pp. 651-661

Author(s):

Paulo E. P. Teixeira ◽

Hanan I. Zehry ◽

Swapnali Chaudhari ◽

Laura Dipietro ◽

Felipe Fregni

Keyword(s):

Knee Osteoarthritis ◽

Pain Intensity ◽

Pain Perception ◽

Small Sample Size ◽

Linear Regression Analysis ◽

Small Sample ◽

Pain Modulation ◽

Clinical Variables ◽

Pain Scores ◽

Intensity Perception

AbstractBackground and aimsPain is a disabling symptom in knee osteoarthritis (KOA) and its underlying mechanism remains poorly understood. Dysfunction of descending pain modulatory pathways and reduced pain inhibition enhance pain facilitation in many chronic pain syndromes but do not fully explain pain levels in chronic musculoskeletal conditions. The objective of this study is to explore the association of clinical variables with pain intensity perception in KOA individuals with varying levels of Conditioned Pain Modulation (CPM) response.MethodsThis is a cross-sectional, exploratory analysis using baseline data of a randomized clinical trial investigating the effects of a non-invasive brain stimulation treatment on the perception of pain and functional limitations due to KOA. Sixty-three subjects with KOA were included in this study. Data on pain perception, mood perception, self-reported depression, physical function, quality of life, and quantitative sensory testing was collected. Multiple linear regression analysis was performed to explore the association between the clinical variables with pain perception for individuals with different levels of CPM response.ResultsFor KOA patients with limited CPM response, perception of limitations at work/other activities due to emotional problems and stress scores were statistically significantly associated with pain scores, F(2, 37) = 7.02, p < 0.01. R-squared = 0.275. For KOA patients with normal CPM response, general health perception scores were statistically significantly associated with pain scores, F(1, 21) = 5.60, p < 0.05. R-squared = 0.2104. Limitations of this study include methodology details, small sample size and study design characteristics.ConclusionsPain intensity perception is associated differently with clinical variables according to the individual CPM response. Mechanistic models to explain pain perception in these two subgroups of KOA subjects are discussed.

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Can Residential Greenspace Exposure Improve Pain Experience? A Comparison between Physical Visit and Image Viewing

Healthcare ◽

10.3390/healthcare9070918 ◽

2021 ◽

Vol 9 (7) ◽

pp. 918

Author(s):

Hansen Li ◽

Xing Zhang ◽

Shilin Bi ◽

Yang Cao ◽

Guodong Zhang

Keyword(s):

Heart Rate ◽

State Anxiety ◽

Pain Threshold ◽

Pain Perception ◽

The State ◽

Subjective Stress ◽

Pain Experience ◽

Scenic Beauty ◽

Significant Difference ◽

Pain Stimuli

Reducing the burden of pain via greenspace exposure is a rising research topic. However, insufficient evidence has been found in relation to the environmental effect itself. Residential greenspace, as a convenient but limited natural environment for urban dwellers, has benefits and services yet to be discovered. Therefore, the current study recruited 24 young adults to evaluate the effects of physical visit to, or image viewing of, residential greenspace on pain perception and related psychophysiological outcomes, via simulated pain. Pain threshold and tolerance were recorded via the level of pain stimuli, and pain intensity was evaluated using the Visual Analog Scale (VAS). The state scale of the State–Trait Anxiety Inventory (STAI-S) and two adjective pairs were employed to measure the state anxiety and subjective stress, respectively. Meanwhile, heart rate (HR), heart rate variability (HRV), and blood pressure (BP) were measured to investigate physiological responses. Besides, Scenic Beauty Estimation (SBE) was also employed to assess participants’ preference regarding the experimental environments. The results revealed that visiting the greenspace significantly increased the pain threshold and tolerance, while no significant effect was observed for image viewing. On the other hand, no significant difference was observed in pain-related psychophysiological indices between the experimental settings, but significantly negative associations were found between the scores of SBE and subjective stress and state anxiety. In conclusion, the current study brings experimental evidence of improving pain experience via residential greenspace exposure, while the related psychophysiological benefits require further investigation.

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Percutaneous Fascia Release for Treating Chronic Recurrent Gluteal Myofascial Pain—A Pilot Study of a New Technique

Rehabilitation Process and Outcome ◽

10.4137/rpo.s30483 ◽

2015 ◽

Vol 4 ◽

pp. RPO.S30483 ◽

Cited By ~ 1

Author(s):

Hsin-Shui Chen ◽

Ming-Ta Lin ◽

Chang-Zern Hong ◽

Yueh-Ling Hsieh ◽

Li-Wei Chou

Keyword(s):

Pilot Study ◽

Pain Intensity ◽

Pain Threshold ◽

Myofascial Pain ◽

Pressure Pain Threshold ◽

Small Sample ◽

Myofascial Trigger Points ◽

Pressure Pain ◽

Hip Abduction ◽

Abduction Strength

Objective To investigate the therapeutic effectiveness of percutaneous fascia release to treat chronic recurrent gluteal myofascial pain related to recurrent tendonitis or bursitis at the attachment sites. Methods Five patients (three males, two females; aged 48.6 ± 8.9 years) with myofascial trigger points in the gluteus medius muscle were treated. Outcome measures, including pain intensity, pressure pain threshold, and the relative strength of hip abduction, were assessed before, immediately after, and six months after the treatment. The data measured before and after treatment (different times) on visual analog scale, pressure pain threshold, and relative hip abduction strength were analyzed by Wilcoxon signed-rank test and paired t-test, respectively, for the comparisons between time points. Results Reduction in pain intensity and increase in the pressure pain threshold and the relative hip abduction strength were found in all five patients after treatment when compared with those of before treatment ( P < 0.05). Moreover, all of these improvements existed for at least six months ( P > 0.05). Conclusions Percutaneous fascia release of gluteal muscle insertion sites can be used to treat chronic gluteal pain related to subtrochanteric bursitis to avoid recurrence, if other treatment cannot control the recurrence, although this was demonstrated only on a small sample size without control and blind assessment in the pilot study.

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Swearing as a response to pain: Assessing hypoalgesic effects of novel “swear” words

10.31234/osf.io/cdvyf ◽

2019 ◽

Author(s):

Richard Stephens ◽

Olly May Robertson

Keyword(s):

Heart Rate ◽

Repeated Measures ◽

Neutral Word ◽

Pain Threshold ◽

Pain Perception ◽

Cold Pressor ◽

Pain Tolerance ◽

Mediation Effects ◽

Independent Variable ◽

Cold Pressor Pain

Background: This pre-registered study extends previous findings that swearing alleviates pain tolerance by assessing the effects of a conventional swear word (“fuck”) and two new “swear” words, “fouch” and “twizpipe”.Method: A mixed sex group of participants (N = 92) completed a repeated measures experimental design augmented by mediation analysis. The independent variable was Word with the levels, “fuck” v. “fouch” v. “twizpipe” v. a neutral word. The dependent variables were emotion rating, humour rating, distraction rating, cold pressor pain threshold, cold pressor pain tolerance, pain perception score and change from resting heart rate. Possible mediation effects were assessed for emotion, humour and distraction ratings. Results: For conventional swearing (“fuck”), confirmatory analyses found a 32% increase in pain threshold and a 33% increase in pain tolerance, accompanied by increased ratings for emotion, humour and distraction, relative to the neutral word condition. The new “swear” words, “fouch” and “twizpipe” were rated higher than the neutral word for emotion and humour although these words did not affect pain threshold or tolerance. Changes in heart rate, pain perception and were absent, as were mediation effects.Conclusions: Our data replicate previous findings that repeating a swear word at a steady pace and volume benefits pain tolerance, extending this finding to pain threshold. Our data cannot explain how such effects are manifest, although distraction appears to be of little importance, and emotion is worthy of future study. The new “swear” words did not alleviate pain even though participants rated them as emotion evoking and humorous.

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The Effect of a Single 30-Min Long Term Evolution Mobile Phone-Like Exposure on Thermal Pain Threshold of Young Healthy Volunteers

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15091849 ◽

2018 ◽

Vol 15 (9) ◽

pp. 1849 ◽

Cited By ~ 1

Author(s):

Zsuzsanna Vecsei ◽

György Thuróczy ◽

István Hernádi

Keyword(s):

Mobile Phone ◽

Pain Threshold ◽

Pain Perception ◽

Well Being ◽

Long Term Evolution ◽

Thermal Pain ◽

Term Evolution ◽

Universal Mobile Telecommunications System ◽

Rf Devices

Although the majority of mobile phone (MP) users do not attribute adverse effects on health or well-being to MP-emitted radiofrequency (RF) electromagnetic fields (EMFs), the exponential increase in the number of RF devices necessitates continuing research aimed at the objective investigation of such concerns. Here we investigated the effects of acute exposure from Long Term Evolution (LTE) MP EMFs on thermal pain threshold in healthy young adults. We use a protocol that was validated in a previous study in a capsaicin-induced hyperalgesia model and was also successfully used to show that exposure from an RF source mimicking a Universal Mobile Telecommunications System (UMTS) MP led to mildly stronger desensitization to repeated noxious thermal stimulation relative to the sham condition. Using the same experimental design, we did not find any effects of LTE exposure on thermal pain threshold. The present results, contrary to previous evidence obtained with the UMTS modulation, are likely to originate from placebo/nocebo effects and are unrelated to the brief acute LTE EMF exposure itself. The fact that this is dissimilar to our previous results on UMTS exposure implies that RF modulations might differentially affect pain perception and points to the necessity of further research on the topic.

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The Distinction of Hot Herbal Compress, Hot Compress, and Topical Diclofenac as Myofascial Pain Syndrome Treatment

Journal of Evidence-Based Integrative Medicine ◽

10.1177/2156587217753451 ◽

2018 ◽

Vol 23 ◽

pp. 215658721775345 ◽

Cited By ~ 1

Author(s):

Jurairat Boonruab ◽

Netraya Nimpitakpong ◽

Watchara Damjuti

Keyword(s):

Quality Of Life ◽

Pain Intensity ◽

Range Of Motion ◽

Pain Threshold ◽

Pressure Pain Threshold ◽

Pressure Pain ◽

Cervical Range Of Motion ◽

Topical Diclofenac ◽

Hot Compress

This randomized controlled trial aimed to investigate the distinctness after treatment among hot herbal compress, hot compress, and topical diclofenac. The registrants were equally divided into groups and received the different treatments including hot herbal compress, hot compress, and topical diclofenac group, which served as the control group. After treatment courses, Visual Analog Scale and 36-Item Short Form Health survey were, respectively, used to establish the level of pain intensity and quality of life. In addition, cervical range of motion and pressure pain threshold were also examined to identify the motional effects. All treatments showed significantly decreased level of pain intensity and increased cervical range of motion, while the intervention groups exhibited extraordinary capability compared with the topical diclofenac group in pressure pain threshold and quality of life. In summary, hot herbal compress holds promise to be an efficacious treatment parallel to hot compress and topical diclofenac.

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Myalgia in 30 Patients with Suspected Myopathy

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17072502 ◽

2020 ◽

Vol 17 (7) ◽

pp. 2502

Author(s):

Diana Lehmann Urban ◽

Elizabeth Lehmann ◽

Leila Motlagh Scholle ◽

Torsten Kraya

Keyword(s):

Pain Intensity ◽

Polymyalgia Rheumatica ◽

Pain Sensitivity ◽

Pain Threshold ◽

Neuromuscular Disorders ◽

Pressure Pain Threshold ◽

Neuromuscular Disorder ◽

Weak Correlation ◽

Pressure Pain ◽

Significant Difference

Background: In patients with neuromuscular disorder, only little data of myalgia frequency and characterization exists. To date, only a weak correlation between pain intensity and pressure pain threshold has been found, and it remains enigmatic whether high pain intensity levels are equivalent to high pain sensitivity levels in neuromuscular disorders. Methods: 30 sequential patients with suspected neuromuscular disorder and myalgia were analyzed with regard to myalgia characteristics and clinical findings, including symptoms of depression and anxiety and pain- threshold. Results: A neuromuscular disorder was diagnosed in 14/30 patients. Muscular pain fasciculation syndrome (MPFS) without evidence for myopathy or myositis was diagnosed in 10/30 patients and 6/30 patients were diagnosed with pure myalgia without evidence for a neuromuscular disorder (e.g., myopathy, myositis, MPFS, polymyalgia rheumatica). Highest median pain scores were found in patients with pure myalgia and polymyalgia rheumatica. Pressure pain threshold measurement showed a significant difference between patients and controls in the biceps brachii muscle. Conclusion: Only a weak correlation between pain intensity and pressure pain threshold has been suggested, which is concordant with our results. The hypothesis that high pain intensity levels are equivalent to high pain sensitivity levels was not demonstrated.

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Improvements in Pain, Well-being, Arterial Pressure, and Lower Limb Volume Following Andullation Therapy in Healthy and Unhealthy Humans

Dose-Response ◽

10.1177/1559325819840838 ◽

2019 ◽

Vol 17 (2) ◽

pp. 155932581984083

Author(s):

Alba Parras-Moltó ◽

Juan Ribas-Serna

Keyword(s):

Arterial Pressure ◽

Lower Limb ◽

Pain Threshold ◽

Pain Perception ◽

Well Being ◽

The Body ◽

Control Group ◽

Subjective Perception ◽

Limb Volume ◽

Random Fashion

Our aim was to test the effects of Andullation therapy on pain threshold, pain perception, feeling of well-being, arterial pressure, and leg volume in healthy and unhealthy patients. We used a multidirectional vibration (frequency range: 5–40 Hz; peak-to-peak amplitude: 2–8 mm; acceleration: 0.4–2 m/s2) in an undulatory way through the surface of the body when the patient was in contact with a mattress (“andullation”). The vibes traveled from the heel to the head in a random fashion while the participants (N = 50) were lying on the mattress. We measured the pain threshold using an algometer; pain perception and well-being through a visual analog scale (VAS); arterial pressure with an electronic sphygmomanometer; and leg volume with Kuhnke’s technique. Measurements were made just before the first andullation session and after the fifth andullation session. Every participant received andullation sessions of 30 min a day for 5 consecutive days. The patients’ pain threshold significantly ( P < .001) increased by 34.48% and 25.79% in the lumbar and trapezius zones, respectively, after 5 sessions of therapy. The subjective perception of pain decreased by 52.3% and the feeling of well-being increased by 45.1%. The systolic and diastolic pressures significantly ( P < .001) decreased by 6.44 and 4.68 mm Hg on average, respectively. Leg volume significantly decreased ( P < .01) by 64.39 mL after the fifth andullation session. Despite not including a control group in our study, the andullation intervention showed an improvement in pain, well-being, arterial pressure, and lower limb volume in the studied population.

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