Imbalance of proresolving lipid mediators in persistent allodynia dissociated from signs of clinical arthritis: erratum
No abstract available (Source: Pain)
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Erratum Source Type: research

Reply to Venda Nova et al.
No abstract available (Source: Pain)
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Correspondence Source Type: research

Looking beyond the obvious: the importance of outcomes and outcomes measures in trigeminal neuralgia
No abstract available (Source: Pain)
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Correspondence Source Type: research

Examination of mechanism effects in cognitive behavioral therapy and pain education: analyses of weekly assessments
Psychosocial treatments for chronic pain produce favorable outcomes. However, we still do not know precisely by what mechanisms or techniques these outcomes are wrought. In secondary analyses of a 10-week group intervention study comparing the effects of literacy-adapted cognitive behavioral therapy (CBT) with literacy-adapted pain education (EDU) among patients with chronic pain, low-socioeconomic status, and low literacy, the Learning About My Pain trial, we examined whether pain catastrophizing was a mechanism specific to CBT. Participants (N = 168) completed mechanism and outcome measures weekly for the 10 weeks of gro...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

A Glra3 phosphodeficient mouse mutant establishes the critical role of protein kinase A–dependent phosphorylation and inhibition of glycine receptors in spinal inflammatory hyperalgesia
Glycinergic neurons and glycine receptors (GlyRs) exert a critical control over spinal nociception. Prostaglandin E2 (PGE2), a key inflammatory mediator produced in the spinal cord in response to peripheral inflammation, inhibits a certain subtype of GlyRs (α3GlyR) that is defined by the inclusion of α3 subunits and distinctly expressed in the lamina II of the spinal dorsal horn, ie, at the site where most nociceptive nerve fibers terminate. Previous work has shown that the hyperalgesic effect of spinal PGE2 is lost in mice lacking α3GlyRs and suggested that this phenotype results from the prevention of P...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Open-label placebo vs double-blind placebo for irritable bowel syndrome: a randomized clinical trial
This study had 2 objectives: first, to determine whether OLP treatment is superior to no-pill control (NPC) in irritable bowel syndrome (IBS) and, second, to compare the efficacy of OLP against double-blind placebo (DBP). In a 6-week, 3-arm, randomized clinical trial, participants were randomized in equal proportions to 3 arms: OLP, DBP, or NPC. Two hundred sixty-two adults (72.9% women), with a mean age of 42.0 (SD = 18.1) years, participated in the primary study. The mean improvement on the IBS Severity Scoring System from baseline to the 6-week end point was significantly greater in OLP compared with that in NPC (90.6 v...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

OnabotulinumtoxinA affects cortical recovery period but not occurrence or propagation of cortical spreading depression in rats with compromised blood–brain barrier
We report (1) that scalp (head) but not lumbar (back) injections of BoNT-A shorten the period of profound depression of spontaneous cortical activity that follows a pinprick-induced cortical spreading depression (CSD); (2) that neither scalp nor lumbar injections prevent the induction, occurrence, propagation, or spreading velocity of a single wave of CSD; (3) that cleaved SNAP25—one of the most convincing tools to determine the anatomical targeting of BoNT-A treatment—could easily be detected in pericranial muscles at the injection sites and in nerve fibers of the intracranial dura, but not within any cortical...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Encoding of cutaneous stimuli by lamina I projection neurons
Lamina I of the dorsal horn, together with its main output pathway, lamina I projection neurons, has long been implicated in the processing of nociceptive stimuli, as well as the development of chronic pain conditions. However, the study of lamina I projection neurons is hampered by technical challenges, including the low throughput and selection biases of traditional electrophysiological techniques. Here we report on a technique that uses anatomical labelling strategies and in vivo imaging to simultaneously study a network of lamina I projection neurons in response to electrical and natural stimuli. Although we were able ...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Baseline resting-state functional connectivity determines subsequent pain ratings to a tonic ecologically valid experimental model of orofacial pain
Pain is a subjective experience with significant individual differences. Laboratory studies investigating pain thresholds and experimental acute pain have identified structural and functional neural correlates. However, these types of pain stimuli have limited ecological validity to real-life pain experiences. Here, we use an orthodontic procedure—the insertion of an elastomeric separator between teeth—which typically induces mild to moderate pain that peaks within 2 days and lasts several days. We aimed to determine whether the baseline structure and resting-state functional connectivity of key regions along t...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Astrocytes mediate migraine-related intracranial meningeal mechanical hypersensitivity
The genesis of the headache phase in migraine with aura is thought to be mediated by cortical spreading depression (CSD) and the subsequent activation and sensitization of primary afferent neurons that innervate the intracranial meninges and their related large vessels. Yet, the exact mechanisms underlying this peripheral meningeal nociceptive response remain poorly understood. We investigated the relative contribution of cortical astrocytes to CSD-evoked meningeal nociception using extracellular single-unit recording of meningeal afferent activity and 2-photon imaging of cortical astrocyte calcium activity, in combination...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Spinal nociceptive sensitization and plasma palmitoylethanolamide levels during experimentally induced migraine attacks
Migraine pathophysiology has been suggested to include dysregulation of the endocannabinoid system (ES). We simultaneously evaluated plasma anandamide (AEA) and palmitoylethanolamide (PEA) levels and spinal sensitization in a validated human model of migraine based on systemic nitroglycerin (NTG) administration. Twenty-four subjects with episodic migraine (MIG) and 19 healthy controls (HC) underwent blood sampling and investigation of nociceptive withdrawal reflex thresholds (RTh: single-stimulus threshold; TST: temporal summation threshold) before and 30 (T30), 60 (T60), and 120 (T120) minutes after sublingual NTG adminis...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Protective role of natural killer cells in neuropathic pain conditions
During the past few years, the research of chronic neuropathic pain has focused on neuroinflammation within the central nervous system and its impact on pain chronicity. As part of the ERA-Net NEURON consortium, we aimed to identify immune cell patterns in the cerebrospinal fluid (CSF) of patients with herpes zoster neuralgia and patients with polyneuropathy (PNP), which may contribute to pain chronicity in these neuropathic pain conditions. Cerebrospinal fluid of 41 patients (10 herpes zoster and 31 PNP) was analyzed by flow cytometry identifying lymphocyte subsets: CD4+ (T-helper cells), CD8+ (cytotoxic T cells), CD19+ (...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Preclinical models of endometriosis and interstitial cystitis/bladder pain syndrome: an Innovative Medicines Initiative-PainCare initiative to improve their value for translational research in pelvic pain
Endometriosis (ENDO) and interstitial cystitis/bladder pain syndrome (IC/BPS) are chronic pain conditions for which better treatments are urgently needed. Development of new therapies with proven clinical benefit has been slow. We have conducted a review of existing preclinical in vivo models for ENDO and IC/BPS in rodents, discussed to what extent they replicate the phenotype and pain experience of patients, as well as their relevance for translational research. In 1009 publications detailing ENDO models, 41% used autologous, 26% syngeneic, 18% xenograft, and 11% allogeneic tissue in transplantation models. Intraperitonea...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Narrative Review Source Type: research

The Valencia consensus-based adaptation of the IASP complex regional pain syndrome diagnostic criteria
No abstract available (Source: Pain)
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Perspective Source Type: research

Economic evaluations of educational, physical, and psychological treatments for fibromyalgia: a systematic review with meta-analysis
Nonpharmacological interventions are recommended for the treatment of fibromyalgia, but there is a lack of knowledge about the cost-effectiveness of these interventions. The aim of this study was to systematically review economic evaluations of educational, physical, and psychological interventions for the treatment of fibromyalgia. The search was performed in PUBMED, EMBASE, CINAHL, Cochrane Library, Physiotherapy Evidence Database, PsycINFO, EconLit, National Health Service Economic Evaluation Database, and Health Technology Assessment. Economic evaluations of educational, physical, and psychological interventions for ad...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

Efficacy of ketamine in relieving neuropathic pain: a systematic review and meta-analysis of animal studies
In humans, proof of long-term efficacy of ketamine treatment in neuropathic pain is lacking. To improve our understanding of ketamine behavior under various administration conditions, we performed a systematic review and meta-analyses of controlled studies on the efficacy of ketamine in mice and rats with a disease model of nerve injury on relief of allodynia. Searches in PubMed and EMBASE identified 31 unique studies. Four meta-analyses were conducted. The first analysis included 19 comparisons on a single ketamine dose and measurement of effect within 3 hours of dosing and showed an appreciable effect (standardized mean ...
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

Allostasis theory in opioid tolerance
No abstract available (Source: Pain)
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Topical Review Source Type: research

Evidence- and consensus-based adaption of the IASP complex regional pain syndrome diagnostic criteria to the ICD-11 category of chronic primary pain: a successful cooperation of the IASP with the World Health Organization
No abstract available (Source: Pain)
Source: Pain - September 1, 2021 Category: Anesthesiology Tags: Commentary Source Type: research

A randomized trial to assess the immediate impact of acupuncture on quantitative sensory testing, pain, and functional status: erratum
No abstract available (Source: Pain)
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Erratum Source Type: research

Reply to Beaulieu
No abstract available (Source: Pain)
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Correspondence Source Type: research

Cannabinoids and acute/postoperative pain management
No abstract available (Source: Pain)
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Correspondence Source Type: research

Delta opioid receptor regulation of calcitonin gene–related peptide dynamics in the trigeminal complex
Migraine is highly prevalent and is the sixth leading cause worldwide for years lost to disability. Therapeutic options specifically targeting migraine are limited, and delta opioid receptor (DOP) agonists were recently identified as a promising pharmacotherapy. The mechanisms by which DOPs regulate migraine are currently unclear. Calcitonin gene–related peptide (CGRP) has been identified as an endogenous migraine trigger and plays a critical role in migraine initiation and susceptibility. The aim of this study was to determine the behavioral effects of DOP agonists on the development of chronic migraine–associ...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

In anticipation of pain: expectancy modulates corticospinal excitability, autonomic response, and pain perception
Pain is a ubiquitous experience encompassing perceptual, autonomic, and motor responses. Expectancy is known to amplify the perceived and autonomic components of pain, but its effects on motor responses are poorly understood. Understanding expectancy modulation of corticospinal excitability has important implications regarding deployment of adaptive and maladaptive protective behaviours in anticipation of pain. We developed a protocol to compare corticospinal excitability to expected high pain, expected low pain, and critically low pain when high pain was expected. Expecting high pain suppressed corticospinal excitability ...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Active role of the central amygdala in widespread mechanical sensitization in rats with facial inflammatory pain
In this study, we examined the role of the CeA in a novel model of ectopic sensitization of rats. Injection of formalin into the left upper lip resulted in latent bilateral sensitization in the hind paw lasting>13 days in male Wistar rats. Chemogenetic inhibition of gamma–aminobutyric acid-ergic neurons or blockade of calcitonin gene-related peptide receptors in the right CeA, but not in the left, significantly attenuated this sensitization. Furthermore, chemogenetic excitation of gamma-aminobutyric acid-ergic neurons in the right CeA induced de novo bilateral hind paw sensitization in the rats without inflammatio...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Genome-wide association studies of low back pain and lumbar spinal disorders using electronic health record data identify a locus associated with lumbar spinal stenosis
Identifying genetic risk factors for lumbar spine disorders may lead to knowledge regarding underlying mechanisms and the development of new treatments. We conducted a genome-wide association study involving 100,811 participants with genotypes and longitudinal electronic health record data from the Electronic Medical Records and Genomics Network and Geisinger Health. Cases and controls were defined using validated algorithms and clinical diagnostic codes. Electronic health record–defined phenotypes included low back pain requiring healthcare utilization (LBP-HC), lumbosacral radicular syndrome (LSRS), and lumbar spin...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Selective targeting of peripheral cannabinoid receptors prevents behavioral symptoms and sensitization of trigeminal neurons in mouse models of migraine and medication overuse headache
Migraine affects ∼15% of the world's population greatly diminishing their quality of life. Current preventative treatments are effective in only a subset of migraine patients, and although cannabinoids seem beneficial in alleviating migraine symptoms, central nervous system side effects limit their widespread use. We developed peripherally restricted cannabinoids (PRCBs) that relieve chronic pain symptoms of cancer and neuropathies, without appreciable central nervous system side effects or tolerance development. Here, we determined PRCB effectiveness in alleviating hypersensitivity symptoms in mouse models of migraine...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Order does matter: the combined effects of classical conditioning and verbal suggestions on placebo hypoalgesia and nocebo hyperalgesia
This study investigates whether the chronology of verbal suggestion and conditioning, as well as their congruence, affects placebo hypoalgesia and nocebo hyperalgesia. The effects induced in 15 groups were compared. The participants in 8 experimental groups were presented with verbal suggestions that were either congruent or incongruent with classical conditioning. The verbal suggestions were provided either before or after conditioning. In 2 other experimental groups, placebo conditioning or nocebo conditioning was implemented without any verbal suggestion; in 2 groups, verbal suggestion of hypoalgesia or hyperalgesia wit...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Heightened pain facilitation rather than impaired pain inhibition distinguishes those with moderate/severe disability in work-related neck pain
To better understand the mechanisms underpinning work-related neck pain, this cross-sectional and single-blinded study compared somatosensory profiles among sonographers with varied neck disability levels. Based on K-mean cluster analysis of scores on the neck disability index (NDI), participants were classified into no (NDI ≤ 8%, n = 31, reference group), mild (NDI = 10%-20%, n = 43), or moderate/severe (NDI ≥ 22%, n = 18) disability groups. Data were collected on bodily pain distribution and severity and psychological measures including depression, anxiety, pain-catastrophizing, and fear-avoidance beliefs using val...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Day-to-day hedonic and calming effects of opioids, opioid craving, and opioid misuse among patients with chronic pain prescribed long-term opioid therapy
Concerns have been raised regarding the misuse of opioids among patients with chronic pain. Although a number of factors may contribute to opioid misuse, research has yet to examine if the hedonic and calming effects that can potentially accompany the use of opioids contribute to opioid misuse. The first objective of this study was to examine the degree to which the hedonic and calming effects of opioids contribute to opioid misuse in patients with chronic pain. We also examined whether the hedonic and calming effects of opioids contribute to patients' daily levels of opioid craving, and whether these associations were mod...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Does aerobic exercise training alter responses to opioid analgesics in individuals with chronic low back pain? A randomized controlled trial
We tested whether aerobic exercise training altered morphine analgesic responses or reduced morphine dosages necessary for adequate analgesia. Patients with chronic back pain were randomized to an 18-session aerobic exercise intervention (n = 38) or usual activity control (n = 45). Before and after the intervention, participants underwent 3 laboratory sessions (double-blinded, crossover) to assess effects of saline placebo, i.v. morphine (0.09 mg/kg), and i.v. naloxone (12 mg) on low back pain and evoked heat pain responses. Differences in evoked and back pain measures between the placebo and morphine conditions indexed mo...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Perspectives on pain registries
No abstract available (Source: Pain)
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Perspective Source Type: research

Sex differences in neuroimmune and glial mechanisms of pain
Pain is the primary motivation for seeking medical care. Although pain may subside as inflammation resolves or an injury heals, it is increasingly evident that persistency of the pain state can occur with significant regularity. Chronic pain requires aggressive management to minimize its physiological consequences and diminish its impact on quality of life. Although opioids commonly are prescribed for intractable pain, concerns regarding reduced efficacy, as well as risks of tolerance and dependence, misuse, diversion, and overdose mortality rates limit their utility. Advances in development of nonopioid interventions hing...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Comprehensive Review Source Type: research

Barriers and enablers influencing healthcare professionals' adoption of a biopsychosocial approach to musculoskeletal pain: a systematic review and qualitative evidence synthesis
A substantial evidence–practice gap exists between healthcare professionals learning about the biopsychosocial model of pain and adopting this model in clinical practice. This review aimed to explore the barriers and enablers that influence the application of a biopsychosocial approach to musculoskeletal pain in practice, from the clinicians' perspective. Qualitative evidence synthesis was used. Four electronic databases (CINAHL, EMBASE, MEDLINE, and PsycINFO) were searched. Primary qualitative studies were included if they investigated the experiences of primary healthcare professionals using a biopsychosocial model...
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Systematic Review and Meta-Analysis Source Type: research

Evidence-based psychological interventions for adults with chronic pain: precision, control, quality, and equipoise
No abstract available (Source: Pain)
Source: Pain - July 22, 2021 Category: Anesthesiology Tags: Topical Review Source Type: research

Reply to Riddle
No abstract available (Source: Pain)
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Correspondence Source Type: research

Brief one-time mind–body interventions for pain relief before joint arthroplasty
No abstract available (Source: Pain)
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Correspondence Source Type: research

Longitudinal study of early adaptation to the coronavirus disease pandemic among youth with chronic pain and their parents: effects of direct exposures and economic stress
The novel coronavirus disease (COVID-19) has caused prolonged disruptions in daily life for many communities. Little is known about the impact of the COVID-19 pandemic on the health and well-being of youth with chronic pain and their families. We conducted a longitudinal, mixed-methods study to characterize early adaptation to the COVID-19 pandemic among 250 families of youth (ages 12-21 years) diagnosed with chronic headache (64%) or other chronic pain conditions (36%) and to determine whether direct exposures to COVID-19 and secondary economic stress modified symptom trajectories. Youth and parents reported on pain inter...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

MrgprdCre lineage neurons mediate optogenetic allodynia through an emergent polysynaptic circuit
Most cutaneous C fibers, including both peptidergic and nonpeptidergic subtypes, are presumed to be nociceptors and respond to noxious input in a graded manner. However, mechanically sensitive, nonpeptidergic C fibers also respond to mechanical input in the innocuous range, so the degree to which they contribute to nociception remains unclear. To address this gap, we investigated the function of nonpeptidergic afferents using the MrgprdCre allele. In real-time place aversion studies, we found that low-frequency optogenetic activation of MrgrpdCre lineage neurons was not aversive in naive mice but became aversive after spar...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Examining attentional biases, interpretation biases, and attentional control in people with and without chronic pain
Psychological models of chronic pain (CP) highlight cognitive-processing biases (ie, attentional biases, interpretation biases, and attentional control) as pivotal processes that uniquely and synergistically impact the development and maintenance of CP. Very few studies explore multiple cognitive biases, and no studies have examined these 3 processes together in a CP sample. Furthermore, there is a lack of research investigating the relationship between these cognitive processes and pain-relevant variables (eg, pain intensity and pain catastrophising). The current study aimed to (1) compare attentional biases, interpretati...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Targeting novel human transient receptor potential ankyrin 1 splice variation with splice-switching antisense oligonucleotides
Activation of transient receptor potential ankyrin 1 (TRPA1) channels by both environmental irritants and endogenous inflammatory mediators leads to excitation of the nerve endings, resulting in acute sensation of pain, itch, or chronic neurogenic inflammation. As such, TRPA1 channels are actively pursued as therapeutic targets for various pathological nociception and pain disorders. We uncovered that exon 27 of human TRPA1 (hTRPA1) could be alternatively spliced into hTRPA1_27A and hTRPA1_27B splice variants. The resulting channel variants displayed reduced expression, weakened affinity to interact with WT, and suffered f...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Classification algorithm for the International Classification of Diseases-11 chronic pain classification: development and results from a preliminary pilot evaluation
The International Classification of Diseases-11 (ICD-11) chronic pain classification includes about 100 chronic pain diagnoses on different diagnostic levels. Each of these diagnoses requires specific operationalized diagnostic criteria to be present. The classification comprises more than 200 diagnostic criteria. The aim of the Classification Algorithm for Chronic Pain in ICD-11 (CAL-CP) is to facilitate the use of the classification by guiding users through these diagnostic criteria. The diagnostic criteria were ordered hierarchically and visualized in accordance with the standards defined by the Society for Medical Deci...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

A proteome signature for acute incisional pain in dorsal root ganglia of mice
After surgery, acute pain is still managed insufficiently and may lead to short-term and long-term complications including chronic postsurgical pain and an increased prescription of opioids. Thus, identifying new targets specifically implicated in postoperative pain is of utmost importance to develop effective and nonaddictive analgesics. Here, we used an integrated and multimethod workflow to reveal unprecedented insights into proteome dynamics in dorsal root ganglia (DRG) of mice after plantar incision (INC). Based on a detailed characterization of INC-associated pain-related behavior profiles, including a novel paradigm...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Motor action changes pain perception: a sensory attenuation paradigm in the context of pain
We present 2 experiments that investigated sensory attenuation of pain implementing a 2-alternative forced choice paradigm. Particularly, healthy participants received painful stimuli on a moving and nonmoving hand during the execution or the preparation of reaching motor actions. At the end of each trial, they indicated on which hand they perceived the stimulus stronger. The point of subjective equality was obtained to measure sensory attenuation. The intensity (experiment 1) and the threat value (experiment 2) of the pain stimuli were manipulated between-subjects to examine their impact on sensory attenuation. Results of...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

The effects of long-term menstrual pain on pain empathy in women with primary dysmenorrhea
Primary dysmenorrhea (PDM) is not only a painful experience but also affects the psychological and affective states of women. Neuroimaging studies have revealed shared neural substrates for somatic and empathic pains in healthy subjects. However, little is known about the relationship between pain intensity and pain empathy in pain disorders. The cyclic nature of PDM makes it a unique model for investigating this issue during a patients' pain phase. To study how long-term pain modulates empathy for pain, T1-weighted magnetic resonance imaging scans were obtained in 39 PDM patients and 41 matched female healthy controls dur...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Pain-related beliefs, cognitive processes, and electroencephalography band power as predictors and mediators of the effects of psychological chronic pain interventions
The current study used data from a clinical trial to identify variables that are associated with and/or mediate the beneficial effects of 4 psychological chronic pain treatments: one teaching patients self-hypnosis to reduce pain intensity (HYP), one teaching self-hypnosis to change thoughts about pain (hypnotic cognitive therapy [HYP-CT]), one teaching cognitive restructuring skills to change thoughts about pain (cognitive therapy [CT]), and one providing education about pain (ED; included as an active control condition). Of 17 possible mechanism variables examined, and with alpha not corrected for multiple comparisons, s...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Underpredicting pain: an experimental investigation into the benefits and risks
In conclusion, even strong underpredictions of pain can reduce pain (ie, cause assimilation), although not significantly more than medium underpredictions. However, strong underpredictions can cause uncertainty and undermine trust. These findings suggest that healthcare providers may wish to be cautious with providing overly positive information about painful medical procedures. (Source: Pain)
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Thalamic neurometabolite alterations in patients with knee osteoarthritis before and after total knee replacement
The weak association between disability levels and “peripheral” (ie, knee) findings suggests that central nervous system alterations may contribute to the pathophysiology of knee osteoarthritis (KOA). Here, we evaluated brain metabolite alterations in patients with KOA, before and after total knee arthroplasty (TKA), using 1H-magnetic resonance spectroscopy (MRS). Thirty-four presurgical patients with KOA and 13 healthy controls were scanned using a PRESS sequence (TE = 30 ms, TR = 1.7 seconds, voxel size = 15 × 15 × 15 mm). In addition, 13 patients were rescanned 4.1 ± 1.6 (mean ± SD)...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Mechanical sensitization, increased axonal excitability, and spontaneous activity in C-nociceptors after ultraviolet B irradiation in pig skin
Ultraviolet B (UVB) irradiation induces hyperalgesia in human and animal pain models. We investigated mechanical sensitization, increase in axonal excitability, and spontaneous activity in different C-nociceptor classes after UVB in pig skin. We focused on units with receptive fields covering both irradiated and nonirradiated skin allowing intraindividual comparisons. Thirty-five pigs were irradiated in a chessboard pattern, and extracellular single-fibre recordings were obtained 10 to 28 hours later (152 fibers). Units from the contralateral hind limb served as a control (n = 112). Irradiated and nonirradiated parts of th...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Comparing the ICD-11 chronic pain classification with ICD-10: how can the new coding system make chronic pain visible? A study in a tertiary care pain clinic setting
Pain is a frequent reason for patients to ask for medical services. However, systematic information about the extent and impact of pain, especially in developing countries, has not been available up to now. We evaluated whether the 11th edition of the International Statistical Classification of Diseases and Related Health Problems (ICD) can fill this gap by coding all electronic out-patient medical records of the pain clinic at Siriraj Hospital in Thailand in 2019 (8714 visits), using the ICD-10 and ICD-11 browsers referenced on the WHO websites. The 3 most frequent pain-related codes in ICD-10 were R52.2 “other chro...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research

Spinoparabrachial projection neurons form distinct classes in the mouse dorsal horn
Projection neurons in the spinal dorsal horn relay sensory information to higher brain centres. The activation of these populations is shaped by afferent input from the periphery, descending input from the brain, and input from local interneuron circuits. Much of our recent understanding of dorsal horn circuitry comes from studies in transgenic mice; however, information on projection neurons is still based largely on studies in monkey, cat, and rat. We used viral labelling to identify and record from mouse parabrachial nucleus (PBN) projecting neurons located in the dorsal horn of spinal cord slices. Overall, mouse lamina...
Source: Pain - June 24, 2021 Category: Anesthesiology Tags: Research Paper Source Type: research