Habituation to pain: a motivational-ethological perspective
No abstract available (Source: Pain)
Source: Pain - July 25, 2019 Category: Anesthesiology Tags: Topical Review Source Type: research

Cortisol increases visceral pain in women but not in men
No abstract available (Source: Pain)
Source: Pain - July 25, 2019 Category: Anesthesiology Tags: Commentaries Source Type: research

Reflections on hybrid transdiagnostic treatment, pain reduction, and emotion regulation
No abstract available (Source: Pain)
Source: Pain - July 25, 2019 Category: Anesthesiology Tags: Commentaries Source Type: research

Pain relief in children and adolescents
No abstract available (Source: Pain)
Source: Pain - July 25, 2019 Category: Anesthesiology Tags: Commentaries Source Type: research

Reply to Henningsen et al.
No abstract available (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Chronic primary pain: a pain-centered view of the world is too narrow
No abstract available (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Reply to Bornstein et al.
No abstract available (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Vulvodynia: a neglected chronic pain diagnosis
No abstract available (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Plasticity in the dynamic pain connectome associated with ketamine-induced neuropathic pain relief
In this study, we conducted a longitudinal functional MRI study to test the hypothesis that the pain-relieving effect of ketamine is the result of reversal of abnormalities in regional low-frequency brain oscillations (LFOs) and abnormal cross-network functional connectivity (FC) of the dynamic pain connectome. We found that (1) ketamine decreased regional LFOs in the posterior cingulate cortex of the default mode network, (2) a machine-learning algorithm demonstrated that treatment-induced brain changes could be used to make generalizable inferences about pain relief, (3) treatment responders exhibited a significant decre...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

People in pain make poorer decisions
Chronic pain affects 1 in 5 people and has been shown to disrupt attention. Here, we investigated whether pain disrupts everyday decision making. In study 1, 1322 participants completed 2 tasks online: a shopping-decisions task and a measure of decision outcomes over the previous 10 years. Participants who were in pain during the study made more errors on the shopping task than those who were pain-free. Participants with a recurrent pain condition reported more negative outcomes from their past decisions than those without recurrent pain. In study 2, 44 healthy participants completed the shopping-decisions task with and wi...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Targeting the CaVα–CaVβ interaction yields an antagonist of the N-type CaV2.2 channel with broad antinociceptive efficacy
Inhibition of voltage-gated calcium (CaV) channels is a potential therapy for many neurological diseases including chronic pain. Neuronal CaV1/CaV2 channels are composed of α, β, γ and α2δ subunits. The β subunits of CaV channels are cytoplasmic proteins that increase the surface expression of the pore-forming α subunit of CaV. We targeted the high-affinity protein–protein interface of CaVβ's pocket within the CaVα subunit. Structure-based virtual screening of 50,000 small molecule library docked to the β subunit led to the identification of 2-(3,5-dimethylisoxa...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Cerebral cortical dimensions in headache sufferers aged 50 to 66 years: a population-based imaging study in the Nord-Trøndelag Health Study (HUNT-MRI)
Based on previous clinic-based magnetic resonance imaging studies showing regional differences in the cerebral cortex between those with and without headache, we hypothesized that headache sufferers have a decrease in volume, thickness, or surface area in the anterior cingulate cortex, prefrontal cortex, and insula. In addition, exploratory analyses on volume, thickness, and surface area across the cerebral cortical mantle were performed. A total of 1006 participants (aged 50-66 years) from the general population were selected to an imaging study of the head at 1.5 T (HUNT-MRI). Two hundred eighty-three individuals suffere...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The role of afferent input in postamputation pain: a randomized, double-blind, placebo-controlled crossover study
In this randomized, double-blind, placebo-controlled crossover study, we investigated whether a peripheral nerve block could temporarily eliminate phantom and stump pain after amputation. Amputees with constant postamputation pain were included and randomized to receive a nerve block with lidocaine 2% with adrenaline or saline in a crossover design. Spontaneous phantom and stump pain and evoked responses were assessed at baseline and at fixed time-points until 120 minutes after lidocaine or saline injection. The primary outcome was the difference in absolute change between worst pain intensity, either phantom or stump pain...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Kappa opioid signaling in the right central amygdala causes hind paw specific loss of diffuse noxious inhibitory controls in experimental neuropathic pain
Diffuse noxious inhibitory controls (DNICs) is a pain-inhibits-pain phenomenon demonstrated in humans and animals. Diffuse noxious inhibitory control is diminished in many chronic pain states, including neuropathic pain. The efficiency of DNIC has been suggested to prospectively predict both the likelihood of pain chronification and treatment response. Little is known as to why DNIC is dysfunctional in neuropathic pain. Here, we evaluated DNIC in the rat L5/L6 spinal nerve ligation (SNL) model of chronic pain using both behavioral and electrophysiological outcomes. For behavior, nociceptive thresholds were determined using...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Efficacy and safety of loxoprofen sodium topical patch for the treatment of pain in patients with minor acute traumatic limb injuries in Brazil: a randomized, double-blind, noninferiority trial
This study showed that LX-P has a comparable efficacy to LX-T, but with a better safety profile, being a therapeutic option for the treatment of posttraumatic injury pain. (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Somatotopically specific primary somatosensory connectivity to salience and default mode networks encodes clinical pain
Although several studies have found that chronic pain is characterized by increased cross-network connectivity between salience network, sensorimotor network, and default mode network (DMN), a large sample-size investigation allowing for a more reliable evaluation of somatotopic specificity and subgroup analyses with linkage to clinical pain intensity has been lacking. We enrolled healthy adults and a large cohort of patients (N = 181) suffering from chronic low back pain (cLBP). To specifically link brain connectivity with clinical pain intensity, patients were scanned at baseline and after performing physical maneuvers t...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Time for change: an experimental investigation of chronic pain patients' emotional and attitudinal responses to simulated opioid-tapering advice
Clinicians report reluctance to deliver opioid-tapering advice to patients with chronic pain, in part due to concerns that patients will be angry and dissatisfied. An experiment was conducted to examine chronic pain patients' emotional and attitudinal responses to simulated opioid-tapering advice. Patients scheduled for an initial assessment at a tertiary pain clinic and currently taking opioid medications for pain (N = 196) were randomly assigned to view video footage of a standardized patient receiving 1 of 3 forms of treatment advice: (1) stay on current medication (2) change to a different pain medication, or (3) taper...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The Paediatric electronic Persistent Pain Outcomes Collaboration (PaedePPOC): establishment of a binational system for benchmarking children's persistent pain services
This study documents the establishment of PaedePPOC and presents baseline and initial outcome data. Binational consensus meetings determined the measures. Governance structures, collection protocols, information technology, site-specific logistics, and onsite training were achieved within 18 months. Children and parents complete baseline and progress questionnaires. Seven of 10 Australasian services provided data to PaedePPOC, with 1432 patients enrolled until June 2018. At baseline, patients were 12.4 ± (3.0) years, 68% female, 93% Australian-born, and 5% Aboriginal and/or Torres Strait Islander people. Most had mo...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Can a brief psychological expectancy intervention improve postoperative pain? A randomized, controlled trial in patients with breast cancer
Pain after surgery remains a major health problem, calling for optimized treatment regimens to maximize the efficacy of pharmacological interventions. In this randomized controlled trial, we tested in a routine surgical treatment setting whether postoperative pain can be reduced by a brief preoperative intervention, ie, positive verbal suggestions in combination with sham acupuncture, designed to optimize treatment expectations. We hypothesized that the expectancy intervention as add-on to patient-controlled intravenous analgesia with morphine reduces patient-reported postoperative pain and improves satisfaction with analg...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Incident injury is strongly associated with subsequent incident temporomandibular disorder: results from the OPPERA study
Cross-sectional studies confirm, as expected, a positive association between jaw injury and painful temporomandibular disorders (TMDs), but prospective evaluations are lacking. We prospectively assessed incident jaw injury, injury type, and development of TMD in adults aged 18 to 44 years. Data were collected from 3258 individuals from communities surrounding 4 US academic institutes between 2006 and 2008. At enrollment, participants reported no TMD history and no facial injuries in the previous 6 months. Quarterly, follow-up questionnaires assessed incident jaw injury, which was classified as intrinsic (attributed to yawn...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Modification of the Neuropathic Pain Symptom Inventory for use in eye pain (NPSI-Eye)
Chronic eye pain, which has previously been assumed to be due to ocular surface abnormalities (ie, “dry eye [DE] disease”), has recently garnered attention as a potential indicator of neuropathic ocular pain in some patients. The purpose of this study was to evaluate the psychometric properties of a modified version of the Neuropathic Pain Symptom Inventory in individuals with eye pain (NPSI-Eye). Enrolled participants (n = 397) completed the NPSI-Eye, general pain severity questionnaires, DE symptom report, and psychological health indices. Participants also underwent mechanical pain sensitivity testing of the...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Altered gray matter volume in sensorimotor and thalamic regions associated with pain in localized provoked vulvodynia: a voxel-based morphometry study
In this study, we tested the hypotheses that PVD compared with healthy controls (HCs) would demonstrate gray matter volume (GMV) alterations in regions associated with sensorimotor, corticothalamic, and basal ganglia circuits. We also tested the replicability of previously reported gray matter increases in basal ganglia and hippocampal volumes in PVD vs HCs. In addition, disease specificity of GMV alterations were examined by comparing PVD with another chronic pain disorder. Finally, we examine whether GMV alterations are correlated with symptom measures. Structural magnetic resonance imaging was obtained in 119 premenopau...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

A deeper look at pain variability and its relationship with the placebo response: results from a randomized, double-blind, placebo-controlled clinical trial of naproxen in osteoarthritis of the knee
Previous studies have shown a robust correlation between variability of clinical pain scores and responsiveness to placebo (but not active drug) in pain studies, but explanations for these relationships are lacking. We investigated this further by assessing relationship between the Focused Analgesia Selection Test (FAST), a psychophysical method that quantifies pain reporting variability in response to experimental stimuli, variability of daily clinical pain scores as captured using diary, and response to treatment in the context of a randomized controlled crossover trial of naproxen vs placebo in knee osteoarthritis. Evok...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Preventive hypothermia as a neuroprotective strategy for paclitaxel-induced peripheral neuropathy
In conclusion, our findings indicate that early exposure to regional hypothermia alleviates paclitaxel-induced peripheral neuropathy. Therapeutic hypothermia may therefore represent an economical and nonpharmaceutical preventive strategy for CIPN in patients with localized solid tumors. (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

RNA-seq data in pain research–an illustrated guide
No abstract available (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: PAIN Pictured Source Type: research

Migraine understood as a sensory threshold disease
Migraine encompasses a broader spectrum of sensory symptoms than just headache. These “other” symptoms, eg, sensory phobias, cognitive and mood changes, allodynia, and many others indicate an altered sensitivity to sensory input which can be measured, in principle, by quantifying sensory threshold changes longitudinally over time. Photophobia, for example, can be quantified by investigating the discomfort thresholds towards the luminance of light. The aim of this review is to look into how thresholds change in patients with migraine. We performed a PubMed search up to June 2018 targeting all peer-reviewed artic...
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Narrative Review Source Type: research

Cognitive biases in pain: an integrated functional–contextual framework
No abstract available (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Topical Review Source Type: research

Peripheral afferents and the pain experience
No abstract available (Source: Pain)
Source: Pain - June 26, 2019 Category: Anesthesiology Tags: Commentary Source Type: research

Reply to Zaman et al.
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

About the limits of mediation analyses in solving chicken-vs-egg—like type of questions
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Reply to Martin-Saavedra and Saade-Lemus
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Music's objective classification improves quality of music-induced analgesia studies
No abstract available (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Correspondence Source Type: research

Pain or nociception? Subjective experience mediates the effects of acute noxious heat on autonomic responses - corrected and republished
Nociception reliably elicits an autonomic nervous system (ANS) response. Because pain and ANS circuitry interact on multiple spinal, subcortical, and cortical levels, it remains unclear whether autonomic responses are simply a reflexive product of noxious stimulation regardless of how stimulation is consciously perceived or whether the experience of pain mediates ANS responses to noxious stimulation. To test these alternative predictions, we examined the relative contribution of noxious stimulation and individual pain experience to ANS responses in healthy volunteers who underwent 1 or 2 pain assessment tasks. Participants...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Corrected and Republished Article Source Type: research

Cisplatin educates CD8+ T cells to prevent and resolve chemotherapy-induced peripheral neuropathy in mice
In conclusion, resolution of CIPN requires in vivo education of CD8+ T cells by exposure to cisplatin. Future studies should examine whether ex vivo CD8+ T cell education could be applied as a therapeutic strategy for treating or preventing CIPN in patients. (Source: Pain)
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

α5GABAA receptors play a pronociceptive role and avoid the rate-dependent depression of the Hoffmann reflex in diabetic neuropathic pain and reduce primary afferent excitability
Diabetic neuropathy is an incapacitating complication in diabetic patients. The cellular and molecular mechanisms involved in this pathology are poorly understood. Previous studies have suggested that the loss of spinal GABAergic inhibition participate in painful diabetic neuropathy. However, the role of extrasynaptic α5 subunit-containing GABAA (α5GABAA) receptors in this process is not known. The purpose of this study was to investigate the role of α5GABAA receptors in diabetes-induced tactile allodynia, loss of rate-dependent depression (RDD) of the Hoffmann reflex (HR), and modulation of primary affer...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Distal infraorbital nerve injury: a model for persistent facial pain in mice
This study characterizes the impact of a distal infraorbital nerve injury, called DIONI, which consists of ligature and transection of distal fibers of the infraorbital nerve. We assessed nociception using a conflict paradigm and optogenetics, and a set of reward, aversion, spatial, temporal, and competition tasks in the IntelliCage to study multiple aspects of cognition, circadian rhythms, and social interactions in groups of mice in home cage environments. Mice with DIONI developed cold and mechanical allodynia, and hypersensitivity towards blue light stimulation. They maintained a long-lasting memory of aversive stimuli...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Experimental evaluation of central pain processes in young women with primary dysmenorrhea
Primary dysmenorrhea (PD; menstrual pain without an underlying medical condition) is associated with enhanced pain sensitivity and temporal summation (TS) in adult women, which may reflect the presence of central pain processes. Research in this area has been limited by focusing on only adult populations and incomplete assessments of central sensitization. The current study explored both excitatory and inhibitory measures of pain processing in girls and young adult women with and without PD. Thirty-two young women with PD and 34 healthy controls underwent laboratory pain testing during each of 3 menstrual cycle phases (men...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Multicolumn spinal cord stimulation for predominant back pain in failed back surgery syndrome patients: a multicenter randomized controlled trial
Despite optimal medical management (OMM), low back pain (LBP) can be disabling, particularly after spinal surgery. Spinal cord stimulation (SCS) is effective in reducing neuropathic leg pain; however, evidence is limited for LBP. This prospective, open-label, parallel-group trial randomized (1:1) failed back surgery syndrome (FBSS) patients with predominant LBP to SCS plus OMM (SCS group) or OMM alone (OMM group) at 28 sites in Europe and the Americas. If trial stimulation was successful, a multicolumn SCS system was implanted. Outcomes were assessed at baseline (before randomization) and at 1, 3, 6, and 12 months after ra...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The serum protease network—one key to understand complex regional pain syndrome pathophysiology
Complex regional pain syndrome (CRPS) develops after fracture. The acute CRPS phenotype resembles exaggerated inflammation, which is explained by local and systemic activation of a proinflammatory network including peptides and cytokines. Epidemiologic data suggest that inactivation of the peptidase angiotensin-converting enzyme in patients treated for hypertension increases the odds to develop CRPS. This hint leads us to investigate the serum protease network activity in patients with CRPS vs respective controls. For this purpose, we developed a dabsyl-bradykinin (DBK)-based assay and used it to investigate patients with ...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Nociceptin/orphanin FQ receptor modulates painful and fatigue symptoms in a mouse model of fibromyalgia
This study investigated the effects of nociceptin/orphanin FQ (N/OFQ) receptor (NOPr) ligands and the modulation of the NOP system in the preclinical mouse model of reserpine-induced fibromyalgia. The effects of administration of the natural agonist N/OFQ and the selective NOPr antagonists (UFP-101 and SB-612111) were evaluated in fibromyalgia-related symptoms in reserpine-treated mice. The expression of prepronociceptin/orphanin FQ and NOPr was assessed in central and peripheral sites at different time points after reserpine administration. Nociceptin/orphanin FQ displayed dual effects in the behavioral changes in the res...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

SUMMIT-07: a randomized trial of NKTR-181, a new molecular entity, full mu-opioid receptor agonist for chronic low-back pain
NKTR-181, a new molecular entity, mu-opioid receptor agonist with an inherently slow rate of central nervous system (CNS) entry, was designed to provide analgesia while reducing abuse potential. This phase 3, enriched-enrollment, randomized-withdrawal trial evaluated the analgesic efficacy, safety, and tolerability of NKTR-181 in patients with chronic low-back pain (CLBP). Adults with moderate-to-severe CLBP refractory to nonopioid analgesics achieving an analgesic NKTR-181 dosage (100-400 mg twice daily) during the open-label titration period were randomized to continued NKTR-181 treatment, double-blind, or switched to pl...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Insight into the genetic architecture of back pain and its risk factors from a study of 509,000 individuals
Back pain (BP) is a common condition of major social importance and poorly understood pathogenesis. Combining data from the UK Biobank and CHARGE consortium cohorts allowed us to perform a very large genome-wide association study (total N = 509,070) and examine the genetic correlation and pleiotropy between BP and its clinical and psychosocial risk factors. We identified and replicated 3 BP-associated loci, including one novel region implicating SPOCK2/CHST3 genes. We provide evidence for pleiotropic effects of genetic factors underlying BP, height, and intervertebral disk problems. We also identified independent genetic c...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Differential activation of ascending noxious pathways associated with trigeminal nerve injury
Trigeminal spinal subnucleus caudalis (Vc) neurons that project to the ventral posteromedial thalamic nucleus (VPM) and parabrachial nucleus (PBN) are critical for orofacial pain processing. We hypothesized that persistent trigeminal nerve injury differentially alters the proportion of Vc neurons that project to VPM and PBN in a modality-specific manner. Neuroanatomical approaches were used to quantify the number of Vc neurons projecting to VPM or PBN after chronic constriction injury of the infraorbital nerve (ION-CCI) and subsequent upper-lip stimulation. Male rats received injections of retrograde tracer fluorogold into...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

The role of Nav1.7 in human nociceptors: insights from human induced pluripotent stem cell–derived sensory neurons of erythromelalgia patients
The chronic pain syndrome inherited erythromelalgia (IEM) is attributed to mutations in the voltage-gated sodium channel (NaV) 1.7. Still, recent studies targeting NaV1.7 in clinical trials have provided conflicting results. Here, we differentiated induced pluripotent stem cells from IEM patients with the NaV1.7/I848T mutation into sensory nociceptors. Action potentials in these IEM nociceptors displayed a decreased firing threshold, an enhanced upstroke, and afterhyperpolarization, all of which may explain the increased pain experienced by patients. Subsequently, we investigated the voltage dependence of the tetrodotoxin-...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Analgesic prescribing trends in a national sample of older veterans with osteoarthritis: 2012-2017
Few investigations examine patterns of opioid and nonopioid analgesic prescribing and concurrent pain intensity ratings before and after institution of safer prescribing programs such as the October 2013 Veterans Health Administration system-wide Opioid Safety Initiative (OSI) implementation. We conducted a quasi-experimental pre–post observational study of all older U.S. veterans (≥50 years old) with osteoarthritis of the knee or hip. All associated outpatient analgesic prescriptions and outpatient pain intensity ratings from January 1, 2012 to December 31, 2016, were analyzed with segmented regression of interru...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Abnormal medial prefrontal cortex functional connectivity and its association with clinical symptoms in chronic low back pain
Accumulating evidence has shown that complicated brain systems are involved in the development and maintenance of chronic low back pain (cLBP), but the association between brain functional changes and clinical outcomes remains unclear. Here, we used resting-state functional magnetic resonance imaging (fMRI) and multivariate pattern analysis to identify abnormal functional connectivity (FC) between the default mode, sensorimotor, salience, and central executive brain networks in cLBP and tested whether abnormal FCs are related to pain and comorbid symptoms. Fifty cLBP patients and 44 matched healthy controls (HCs) underwent...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Pain coping skills training for African Americans with osteoarthritis: results of a randomized controlled trial
African Americans bear a disproportionate burden of osteoarthritis (OA), but they have been underrepresented in trials of behavioral interventions for pain. This trial examined a culturally tailored pain coping skills training (CST) program, compared to a wait list control group, among 248 African Americans with knee or hip OA. The pain CST program involved 11 telephone-based sessions over 3 months. Outcomes were assessed at baseline, 3 months (primary), and 9 months, and included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale (primary outcome), WOMAC total score and function subsc...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Platelet-derived growth factor activates nociceptive neurons by inhibiting M-current and contributes to inflammatory pain
Endogenous inflammatory mediators contribute to the pathogenesis of pain by acting on nociceptors, specialized sensory neurons that detect noxious stimuli. Here, we describe a new factor mediating inflammatory pain. We show that platelet-derived growth factor (PDGF)-BB applied in vitro causes repetitive firing of dissociated nociceptor-like rat dorsal root ganglion neurons and decreased their threshold for action potential generation. Injection of PDGF-BB into the paw produced nocifensive behavior in rats and led to thermal and mechanical pain hypersensitivity. We further detailed the biophysical mechanisms of these PDGF-B...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Quantitative assessment of nonpelvic pressure pain sensitivity in urologic chronic pelvic pain syndrome: a MAPP Research Network study
Experimental pain sensitivity was assessed in individuals with urologic chronic pelvic pain syndrome (UCPPS) as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network. A series of computer-controlled pressure stimuli were delivered to the thumbnail bed, an asymptomatic site distant from the area of UCPPS pain that is considered to be indicative of overall body pain threshold. Stimuli were rated according to a standardized magnitude estimation protocol. Pain sensitivity in participants with UCPPS was compared with healthy controls and a mixed pain group composed of individuals wit...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research

Compared to limb pain of other origin, ultrasonographic osteodensitometry reveals loss of bone density in complex regional pain syndrome
Local osteopenia and altered bone metabolism are major complications of complex regional pain syndrome (CRPS), but quantitative assessment is difficult unless using X-ray or dual-energy X-ray absorptiometry. Ultrasound-based measurement of bone density (UBD) is a possible alternative but has never been used to detect unilateral disease such as CRPS. Therefore, the main outcome measure of this prospective study was the diagnostic utility of UBD in patients with lower-limb CRPS. Second, we compared the extent of unilateral and contralateral calcaneal bone density to that of other conditions with unilateral pain, general oste...
Source: Pain - May 23, 2019 Category: Anesthesiology Tags: Research Paper Source Type: research