Sunday, March 31, 2019

Combination pharmacotherapy for tackling descending controls and central sensitisation

Abstract

In this issue you will find a paper by Stevie Lockwood and Anthony Dickenson entitled “A combination pharmacotherapy of tapentadol and pregabalin to tackle centrally driven osteoarthritis pain” (Lockwood and Dickenson, 2019). This electrophysiological study in the monoiodoacetate (MIA) model of osteoarthritis in rats has important implications for personalised pain management, suggesting that patients with dysfunctional descending pain control will likely benefit from noradrenaline reuptake inhibitors (“endogenous pain control boosters”), while patients with evidence for central sensitisation are likely to benefit from gabapentinoids.

This article is protected by copyright. All rights reserved.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2FLIjR5
via IFTTT

Saturday, March 30, 2019

Measuring stigma in chronic pain: Preliminary investigation of instrument psychometrics, correlates, and magnitude of change in a prospective cohort attending interdisciplinary treatment

A recent proposal to update the definition of pain states that “[pain] is a distressing experience associated with actual or potential tissue damage with sensory, emotional, cognitive, and social components.”64 This definition highlights the central role of social processes in the pain experience. Consideration of the social context is crucial to understand patients’ adaptation to chronic pain. Supportive social environments, such as those characterized by empathy and validation, may foster well-being among people with chronic pain.

from The Journal of Pain https://ift.tt/2OzVI1b
via IFTTT

Friday, March 29, 2019

Painful Temporomandibular Disorder is Associated with Migraine in Adolescents: a case-control study

Temporomandibular disorders (TMD) refer to alterations or dysfunctions in the masticatory muscles, the temporomandibular joint (TMJ), and associated structures.49 It has been demonstrated that migraine and painful TMD are comorbid in adults, while tension-type headache (TTH), the most common headache subtype, is not.8,19,21–23 Migraine, TTH, and TMD are also highly prevalent in adolescents.1,40

from The Journal of Pain https://ift.tt/2YDxgAT
via IFTTT

Thursday, March 28, 2019

Daily briefing: The gene mutations that cause a woman to feel no pain or fear

Daily briefing: The gene mutations that cause a woman to feel no pain or fear

Daily briefing: The gene mutations that cause a woman to feel no pain or fear, Published online: 28 March 2019; doi:10.1038/d41586-019-01028-6

She also heals quickly (and is forgetful). Plus: A rare collaboration for North Korean physicists and how cellular censuses can guide cancer care.

from Nature - Issue - nature.com science feeds https://ift.tt/2HOBy30
via IFTTT

Physical activity as a prognostic factor of pain intensity and disability in patients with low back pain: a systematic review

Abstract

Background and objective

Identifying factors that influence the course of low back pain (LBP) is important to help clinicians to identify those patients at higher risk of non‐recovery. The objective of this systematic review was to investigate the prognostic role of physical activity in the course of LBP.

Databases and data treatment

Literature searches were conducted in five electronic databases from their inception to February 2018. Prospective cohort studies investigating the influence of any type of physical activity in people with LBP were considered eligible. The primary outcomes were pain intensity and disability. Two independent reviewers extracted the data and assessed the methodological quality of the included studies. Results were stratified according to participants’ symptoms duration at baseline.

Results

Twelve studies were considered eligible for this review. Of these, six included patients with chronic LBP, four studies did not specify the patients’ duration of symptoms, one study included patients with acute LBP, and one study included patients with subacute LBP. Included studies were heterogeneous in terms of physical activity assessment, outcomes, follow‐up duration, and statistical methods, therefore, pooling of results was not performed. We found limited evidence to support the prognostic role of physical activity in the course of LBP.

Conclusions

Our review identified limited evidence supporting physical activity as a prognostic factor in LBP. Future cohort studies are needed to clarify the strength and importance of this association.

This article is protected by copyright. All rights reserved.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2HYA2L8
via IFTTT

Podcast: Human impacts on Mount Kilimanjaro, sex differences in pain, and a crystal-based cooling method

Podcast: Human impacts on Mount Kilimanjaro, sex differences in pain, and a crystal-based cooling method

Podcast: Human impacts on Mount Kilimanjaro, sex differences in pain, and a crystal-based cooling method, Published online: 27 March 2019; doi:10.1038/d41586-019-01004-0

Hear the latest from the world of science, brought to you by Benjamin Thompson and Shamini Bundell.

from Nature - Issue - nature.com science feeds https://ift.tt/2YxfnU0
via IFTTT

Wednesday, March 27, 2019

Improvement in Work Ability, Psychological Distress and Pain Sites in Relation to Low Back Pain Prognosis: A Longitudinal Observational Study in Primary Care

imageStudy Design. Prospective observational study pooled from two clinical cohorts. Objective. To investigate the longitudinal relation between multisite pain, psychological distress, and work ability with disability, pain, and quality of life. Summary of Background Data. Knowledge of prognostic factors is essential for better management of patients with low back pain (LBP). All domains of the biopsychosocial model have shown prognostic value; however, clinical studies rarely incorporate all domains when studying treatment outcome for patients with LBP. Methods. A total of 165 patients with nonspecific LBP seeking primary care physiotherapy were included. Mixed-effects models were used to estimate longitudinal relations between the exposure variables and concurrent measures of outcomes at baseline and 3 months. Logistic regression was used to estimate odds ratios for minimal important difference in outcome. Results. Higher work ability was associated with less disability −2.6 (95% confidence interval [CI]: −3.3, −2.0), less pain: −0.4 (95% CI: −0.5, −0.3), and higher quality of life 0.03 (95% CI: 0.02, 0.04). Higher psychological distress and number of pain sites were associated with higher disability: 10.9 (95% CI: 7.7, 14.1) and 2.3 (95% CI: 1.4, 3.2) higher pain: 1.9 (95% CI: 1.3, 2.5) and 0.4 (95% CI: 0.2, 0.5), and lower quality of life: −0.1 (95% CI: −0.2, −0.1) and −0.02 (95% CI: −0.03, −0.01), respectively. Improvement in work ability showed consistent associations with successful outcome for disability (odds ratio [OR]: 4.8, 95% CI: 1.3, 18.1), pain (OR: 3.6, 95% CI: 1.1, 12.1), and quality of life (OR: 4.5, 95% CI: 1.4, 15.1) at 3 months. Reduced psychological distress was associated with improvement in pain only (OR 4.0, 95% CI: 1.3, 12.3). Conclusion. More pain sites, higher psychological distress, or lower work ability showed higher disability, more pain, and lower quality of life in patients with LBP. Only improvement in work ability was consistently related to successful outcomes. Level of Evidence: 2

from Spine - Featured Articles - Featured Articles https://ift.tt/2Ujyx0k
via IFTTT

Evaluating the Quality, Content, and Readability of Online Resources for Failed Back Spinal Surgery

imageStudy Design. An Internet-based assessment of websites using recognized score systems. Objective. To assess the quality, content, and readability of online information for failed back spinal surgery (FBSS). Summary of Background Data. A significant amount of patients still suffer from chronic or recurrent back pain with or without radicular symptoms after spinal surgery. More and more patients use the Internet to find health-related information. Low-quality or inaccurate information may not only misleading patients but also have a negative impact on the trust between patients and physicians. Methods. The terms “chronic pain after spinal surgery,” “chronic pain after back surgery,” “failed back surgery syndrome,” “post spinal surgery syndrome,” and “post laminectomy syndrome” were entered into three search engines (Google, Yahoo!, and Bing). The first 25 websites from each search were reviewed. The quality, content, and readability of each website were evaluated using DISCERN score, FBSS-specific content score, and the Journal of the American Medical Association (JAMA) benchmark criteria, the first two score systems were assessed by three reviewers independently. The Flesch-Kincaid grade level (FKGL) was used to assess the readability. Each website with or without the Health on the Net Code (HONcode) was also recorded. Results. Seventy-two websites were analyzed in our study. The average DISCERN score for all websites was 35.26 ± 11.45, indicating the quality of the websites was poor. The DISCERN score of physician websites was 31.25 ± 9.08, lower than that of media (36.50 ± 0.71, P = 0.017) and commercial websites (42.55 ± 10.93, P = 0.045). The mean FBSS-specific content score was 9.58 ± 3.90 out of maximum 25. We failed to find any difference of FBSS-specific content score among different type of website. Websites with HONcode certification were associated with higher DISCERN score, FBSS-specific content score, and JAMA benchmark criteria score than non-certified websites. The mean FKGL was 12.19 ± 2.20, and none of the websites’ FKGL was lower than the six grade level. Conclusion. The quality and content of available online information for FBSS were poor. The readability of online information in our results showed a significantly higher reading level than the sixth-grade level recommended by the AMA and NIH. Level of Evidence: 4

from Spine - Featured Articles - Featured Articles https://ift.tt/2Ujywti
via IFTTT

Psychometric Properties Study of the Oswestry Disability Index in a Spanish Population With Previous Lumbar Disc Surgery: Homogeneity and Validity

imageStudy Design. Evaluation of the psychometric properties of a questionnaire. Objective. To assess the psychometric properties of the Spanish version of the Oswestry Disability Index (ODI) in a Spanish population with previous lumbar disc surgery. Summary of Background Data. ODI is frequently used for measuring disability in spinal disorders. In 1995, ODI was translated and transculturally adapted into the Spanish context; its content and apparent validity, internal consistency and test–retest reliability were demonstrated for a Spanish population with lumbar pain. However, this score has not been tested in terms of discriminative capacity (floor and ceiling effects) and construct validity. Methods. Two hundred seventy-five patients who had previously undergone surgical treatment for disc lumbar herniation completed the ODI, Short-Form 36 (SF36), EuroQol-5D (EQ5D), and Numerical Rating Scale for Back Pain. Internal consistency, floor and ceiling effects and construct validity (convergent, divergent, and “known-groups” validities) were assessed. Results. Spanish ODI showed a very good internal consistency: Cronbach-α coefficient for ODI score was 0.928; Cronbach-α coefficient, if the item was deleted, did not increase by more than 0.1 for each item; and Item-total correlations ranged from strong to very strong. There was floor effect for both ODI score and for all individual items. There was no ceiling effect. Spanish ODI showed very good construct validity because 88% (7/8) of the hypotheses about convergent, divergent and “known-groups” validities were supported. Concerning convergent validity, ODI was strongly correlated with the Numerical Rating Scale for Back Pain (0.717; P < 0.001), SF36-Utility (rho = −0.786; P < 0.001), Physical Component Summary score SF36 (rho = −0.787; P < 0.001), Mental Component Summary score SF36 (rho = −0.605; P < 0.001), EQ5D-Utility (rho = −0.833; P < 0.001) and some EQ5D physical components. Conclusion. Spanish ODI showed good psychometric properties (internal consistency and construct validity), similar to others validation studies. Spanish ODI is a valid instrument for the measurement of disability in Spanish patients with previous lumbar disc surgery, specifically in patients with moderate/intense disability. Level of Evidence: 4

from Spine - Featured Articles - Featured Articles https://ift.tt/2JKDWte
via IFTTT

Cross-cultural Adaptation and Validation of the Simplified-Chinese Version of Neck Bournemouth Questionnaire for Patients in Mainland China

imageStudy Design. A prospective study. Objective. The aim of this study was to develop and assess the internal reliability and structure validity of a simplified Chinese version of the Neck Bournemouth Questionnaire (SC-NBQ) for evaluation of patients with nonspecific neck pain (NP) in mainland China. Summary of Background Data. The NBQ has been cross-culturally translated into several languages with good internal consistency and construct validity to evaluate low back pain and NP. However, the NBQ has been not translated or validated for Chinese-speaking patients. Methods. The SC-NBQ was developed by standard cross-translation procedures, and completed by 106 patients with nonspecific NP, along with other self-reported questionnaires, including the Neck Disability Index (NDI), Hospital Anxiety and Depression Scale (HADS), Functional Rating Index (FRI), and 36-Item Short Form Health Survey (SF-36). The internal consistency, test-retest reliability, and construct validity of the SC-NBQ were determined. Results. The NBQ was successfully translated into Chinese. All patients completed the SC-NBQ twice, and the other instruments. Score distribution demonstrated that there was no floor or ceiling effects of the SC-NBQ. Cronbach α coefficient (α = 0.89) and intraclass correlation coefficient (ICC = 0.97) showed good internal consistency and test-retest reliability. A good construct validity was shown by strong correlation with HADS (r = 0.75), NDI (r = 0.82), FRI (r = 0.90) and SF-36 physical functioning (r = 0.75), and bodily pain (r = 0.75) subscales. Conclusion. The SC-NBQ demonstrated good internal consistency, test-retest reliability, and construct validity, and may be used for the evaluation of NP in Chinese-speaking patients. Level of Evidence: 2

from Spine - Featured Articles - Featured Articles https://ift.tt/2UdgJUN
via IFTTT

Time Taken to Return to Work Does Not Influence Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Fusion: A 5-Year Follow-Up Study

imageStudy Design. Retrospective cohort study using prospectively collected registry data. Objective. To determine factors which influence return-to-work (RTW) in patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and to determine if early RTW affects functional outcomes. Summary of Background Data. MIS-TLIF has been associated with accelerated return to work. RTW in non-WC working-age adults after MIS-TLIF is not well understood. Methods. Prospectively collected registry data of 907 patients who underwent MIS-TLIF at a single institution from 2004 to 2013 were reviewed. One hundred ten working adults who underwent single-level MIS-TLIF with complete preoperative and 5-year postoperative follow-up data were included. Patients were assigned into Early RTW (≤60 d, n = 40) and Late RTW (>60 d, n = 70). All patients were assessed pre- and postoperatively at 2 and 5 years. Length of operation, length of stay, and comorbidities were also recorded. Results. The Early RTW group had significantly lower Oswestry Disability Index (ODI), North American Spine Society score for neurogenic symptoms (NASS NS), numerical pain rating scale (NPRS) back and leg pain scores than the Late RTW group (<0.01) There were no significant differences in age, body mass index (BMI) and prevalence of medical comorbidities (P > 0.05). In addition, there were no differences in terms of duration of surgery or length of hospitalization. There were no significant differences in ODI, NASS NS, Short-form 36 physical and mental component scores (SF-36 PCS/MCS), NPRS, satisfaction/expectation fulfilment between the Early and Late RTW groups at 2-year and 5-year follow-up. Both groups reported similar proportions that RTW without limitations and return-to-function (RTF) at 2-years and 5-years. Conclusion. Patients who RTW late have significantly poorer preoperative SF-36 physical component scores and higher ODI, NASS NS, NPRS back/leg pain scores. Surgeons should be cognizant that working adults with poorer preoperative function will tend to return to work later, but should reassure them that they will likely achieve similar clinical outcomes, satisfaction and expectation fulfilment when compared with patients who returned to work early. Level of Evidence: 3

from Spine - Featured Articles - Featured Articles https://ift.tt/2JKDUl6
via IFTTT

Why the sexes don’t feel pain the same way

Why the sexes don’t feel pain the same way

Why the sexes don’t feel pain the same way, Published online: 27 March 2019; doi:10.1038/d41586-019-00895-3

After decades of assuming that pain processing is equivalent in all sexes, scientists are finding that different biological pathways can produce an ‘ouch!’.

from Nature - Issue - nature.com science feeds https://ift.tt/2WqCYE7
via IFTTT

Cannabis should be used cautiously, particularly in chronic pain

Hurley writes: “Very few UK patients have gained access to previously illegal cannabis based medicinal products since doctors were given permission to prescribe them in November 2018, and patients...


from Latest headlines from BMJ https://ift.tt/2OqFFmt
via IFTTT

Monday, March 25, 2019

Kappa opioid signaling in the central nucleus of the amygdala promotes disinhibition and aversiveness of chronic neuropathic pain

imageChronic pain is associated with neuroplastic changes in the amygdala that may promote hyper-responsiveness to mechanical and thermal stimuli (allodynia and hyperalgesia) and/or enhance emotional and affective consequences of pain. Stress promotes dynorphin-mediated signaling at the kappa opioid receptor (KOR) in the amygdala and mechanical hypersensitivity in rodent models of functional pain. Here, we tested the hypothesis that KOR circuits in the central nucleus of the amygdala (CeA) undergo neuroplasticity in chronic neuropathic pain resulting in increased sensory and affective pain responses. After spinal nerve ligation (SNL) injury in rats, pretreatment with a long-acting KOR antagonist, nor-binaltorphimine (nor-BNI), subcutaneously or through microinjection into the right CeA, prevented conditioned place preference (CPP) to intravenous gabapentin, suggesting that nor-BNI eliminated the aversiveness of ongoing pain. By contrast, systemic or intra-CeA administration of nor-BNI had no effect on tactile allodynia in SNL animals. Using whole-cell patch-clamp electrophysiology, we found that nor-BNI decreased synaptically evoked spiking of CeA neurons in brain slices from SNL but not sham rats. This effect was mediated through increased inhibitory postsynaptic currents, suggesting tonic disinhibition of CeA output neurons due to increased KOR activity as a possible mechanism promoting ongoing aversive aspects of neuropathic pain. Interestingly, this mechanism is not involved in SNL-induced mechanical allodynia. Kappa opioid receptor antagonists may therefore represent novel therapies for neuropathic pain by targeting aversive aspects of ongoing pain while preserving protective functions of acute pain.

from PAIN - Featured Articles - Current Issue Highlights https://ift.tt/2OsM28D
via IFTTT

The prevalence and the burden of pain in patients with Huntington disease: a systematic review and meta-analysis

imageAbstract: It is remarkable that studies focusing on the prevalence and the burden of pain in patients with Huntington disease (HD) are scarce. This may lead to inadequate recognition of pain and hence lack of treatment, eventually affecting the quality of life. The aim of this review is to investigate the prevalence of pain and its burden in HD by performing a systematic literature search. In February 2018, a systematic search was performed in the electronic databases of Pubmed, Embase, Cinahl, Cochrane, and PsycINFO. Studies focusing on patients with juvenile HD were excluded. All other types of study were included without language restrictions. In total, 2234 articles were identified, 15 of which met the inclusion criteria and provided information on 2578 patients with HD. The sample-weighted prevalence of pain was 41.3% (95% confidence interval: 36%-46%). The pain burden, which was measured with the SF-36, is significantly less compared with that in the general population. The sample-weighted mean score on the SF-36 was 84 (95% confidence interval: 81-86), where a score of 100 represents the lowest symptom burden. The results demonstrate that pain could be an important nonmotor symptom in patients with HD, and there are indications that the pain burden could be diminished because of HD. Larger and high-quality prospective cohort and clinical studies are required to confirm these findings. In the meantime, awareness about pain and its burden in patients with HD is warranted in clinical practice.

from PAIN - Featured Articles - Current Issue Highlights https://ift.tt/2TUUqDY
via IFTTT

Role of anxiety in young children's pain memory development after surgery

imagePediatric pain is common, and memory for it may be distressing and have long-lasting effects. Children who develop more negatively biased memories for pain (ie, recalled pain is higher than initial pain report) are at risk of worse future pain outcomes. In adolescent samples, higher child and parent catastrophic thinking about pain was associated with negatively biased memories for postsurgical pain. This study examined the influence of child and parent anxiety on the development of younger children's postsurgical pain memories. Seventy-eight children undergoing a tonsillectomy and one of their parents participated. Parents reported on their anxiety (state and trait) before surgery, and trained researchers observationally coded children's anxiety at anaesthesia induction. Children reported on their postsurgical pain intensity and pain-related fear for 3 days after discharge. One month after surgery, children recalled their pain intensity and pain-related fear using the same scales previously administered. Results revealed that higher levels of postsurgical pain and higher parent trait anxiety predicted more negatively biased memories for pain-related fear. Parent state anxiety and child preoperative anxiety were not associated with children's recall. Children who developed negatively biased pain memories had worse postsurgical pain several days after surgery. These findings underscore the importance of reducing parental anxiety and effective postsurgical pain management to potentially buffer against the development of negatively biased pain memories in young children.

from PAIN - Featured Articles - Current Issue Highlights https://ift.tt/2OoZ3QA
via IFTTT

Sunday, March 24, 2019

Hearing other's pain is associated with sensitivity to physical pain: an ERP study

Publication date: Available online 23 March 2019

Source: Biological Psychology

Author(s): Yang Liu, Jing Meng, Manlin Yao, Qian Ye, Bi Fan, Weiwei Peng

Abstract

Numerous studies have demonstrated an overlap between the processing of self-pain and others’ pain, which suggests that psychological and neural representations are shared between the perception of physical pain and empathy for pain. As hearing emotional exclamations is a common way in which we regularly perceive and empathize with others’ pain, the present study aimed to investigate the link between sensitivity to physical pain and the sounds made by others in pain. We recorded event-related potential (ERP) responses to another person’s vocalizations (neutral or painful intonation) and identified electrophysiological responses associated with the processing of painful sounds. Additionally, individual pain sensitivity was characterized by a stimulus-response function that described the relationship between objective stimulus intensity and subjective pain intensity. Results showed that compared with hearing others’ neutral sounds, hearing others’ sounds of pain elicited more positive frontal-central N1 and N2 responses as well as more positive central-parietal P3 and late positive potential responses. These electrophysiological responses to hearing others’ pain replicated electrophysiological responses to observing pictures and video clips of people in pain. Importantly, the neural responses to hearing others in pain were associated with physical pain sensitivity that was indexed by stimulus-response characteristics. The identified link between perception of one’s own physical pain and the sounds of others in pain further supports the shared common psychological computations between processing one’s own pain and empathizing with others’ pain.



from ScienceDirect Publication: Biological Psychology https://ift.tt/2uvh0nj
via IFTTT

Thursday, March 21, 2019

Associations Between Catecholaminergic and Serotonergic Genes and Persistent Arm Pain Severity Following Breast Cancer Surgery

Surgery is the primary treatment for breast cancer. Unfortunately, 25% to 60% of patients will report persistent postsurgical pain following breast cancer surgery.2,19 This pain usually occurs about twelve weeks post-surgery and is characterized by burning, throbbing, or aching in the ipsilateral chest, axilla, and/or arm. This pain is associated with other breast and arm symptoms, including swelling and weakness. While previous studies have identified various demographic and clinical risk factors,1,5,31,40,42,57 as well as physiological factors (e.g., genetic variations9,32,39,64) associated with the development of persistent pain following breast cancer surgery, its exact etiology remains elusive.

from The Journal of Pain https://ift.tt/2HQFcc1
via IFTTT

Iliotibial band syndrome

What you need to knowIliotibial band (ITB) syndrome (ITBS) is the most common cause of lateral knee pain in runners, but may be provoked by other activities such as swimming, rowing, cycling, and...


from Latest headlines from BMJ https://ift.tt/2HytLWX
via IFTTT

Wednesday, March 20, 2019

Tactile precision remains intact when acute neck pain is induced

A rich body of evidence suggests that chronic pain is associated with changes in the structure and function of the central nervous system. This is reflected by structural and functional brain imaging data on chronic low back pain16,49, complex regional pain syndrome31,38, or phantom limb pain14,15. Interestingly, recent findings also provide preliminary insight into similar cortical alterations in chronic neck pain33. Behavioral studies have shown that neck pain is associated with reduced tactile acuity20,35, confirming that patients with long-lasting pain perceive their painful body part less accurately9.

from The Journal of Pain https://ift.tt/2uhjZjj
via IFTTT

Enhanced neural reinstatement for evoked facial pain compared to evoked hand pain

Retrieving and remembering an event can reactivate cortical and subcortical brain regions that were engaged during the event itself.5 Such neural reinstatement has been observed in the auditory,29,42,62 visual,32,44,63 and olfactory system,24 and for emotional words and pictures.34,54 Until now, reinstatement in the nociceptive system has received very little attention, although it might be part of the maladaptive processes contributing to the development and maintenance of chronic pain.18,60 In a recent study we were able to demonstrate reinstatement in the nociceptive system.

from The Journal of Pain https://ift.tt/2Fg8EVQ
via IFTTT

Diagnostic uncertainty in youth with chronic pain and their parents

Pediatric chronic pain, affecting 11-38% of youth,17 can have a profound impact on daily functioning, and is associated with frequent school absences, sleep disturbance, emotional distress, and reduced participation in peer activities.29 The impact of pediatric chronic pain extends to the broader family. For example, parenting a child with chronic pain is associated with anxiety, depressive symptoms, and parenting stress.5 A major challenge that children with chronic pain and their parents face is understanding the cause of the pain.

from The Journal of Pain https://ift.tt/2uhjXbb
via IFTTT

Interhemispheric inhibition is reduced in response to acute muscle pain: a cross-sectional study using transcranial magnetic stimulation

Musculoskeletal pain is known to alter sensorimotor function of the affected body part. For example, individuals with chronic lateral elbow pain (chronic lateral epicondylalgia or ‘Tennis Elbow’) display increased sensitivity to mechanical stimuli,32 decreased maximal wrist extensor force and reduced grip force6,57 on the painful side. Interestingly, bilateral deficits in sensorimotor function are also observed in these individuals, despite the presence of pain in only one limb6,12,18. For example, a recent systematic review demonstrated flexed wrist postures, increased upper-limb reaction times, reduced speed of movement, and reduced pressure and thermal pain thresholds in the unaffected limb of people with chronic lateral elbow pain6,27,49.

from The Journal of Pain https://ift.tt/2Fghhj7
via IFTTT

A definition of flare in low back pain (LBP): A multiphase process involving perspectives of individuals with LBP and expert consensus

Low back pain (LBP) is the most burdensome musculoskeletal condition worldwide [7], affects all ages [17], and contributes to inequality globally [2]. Most individuals experience LBP at least once and for many, LBP is a lifelong problem with trajectories marked by fluctuations [1,14,15,18,28]. Terms such as acute, subacute and chronic, provide little or no information regarding symptom variation, and don't discriminate between chronic LBP and multiple acute periods. The terms episodes [10,12,30], recurrences [12,24] and flares [23,27,31] are used to describe fluctuations, and may characterize LBP trajectories, but it is unclear how they are defined and differ.

from The Journal of Pain https://ift.tt/2ulDtn4
via IFTTT

Exercise induced hypoalgesia in pain-free and chronic pain populations: State of the art and future directions

Chronic pain is a pervasive condition, affecting an estimated 20% of all people worldwide.10,13,48 It is typically defined as pain persisting beyond the expected time of healing (e.g. after injury or surgery), or ongoing pain lasting for ≥ 3 months.133 Exercise is considered an important component of effective chronic pain management. It has a number of potential benefits, including improving physical function84 and mood,54 as well as decreasing the risk of secondary health problems including cardiovascular, metabolic, bone and neurodegenerative disorders.

from The Journal of Pain https://ift.tt/2FfBtSg
via IFTTT

Friday, March 15, 2019

The relative efficacy of mindfulness versus distraction: The moderating role of attentional bias

Abstract

Background

This study investigated whether the ability to disengage quickly from pain‐related stimuli moderated the relative efficacy of a mindfulness‐based intervention versus distraction in response to an experimental pain task.

Methods

Participants (n = 100) completed a dot probe task with eye tracking and were then randomized (2:2:1) to receive a mindfulness‐based interoceptive exposure task (MIET), distraction instructions or no instructions (control group) before engaging in the cold pressor test.

Results

Participants who were allocated to the MIET condition reported a significantly higher pain threshold and distress than the distraction group, although not significantly higher than the control group. Those in the MIET group had improved tolerance compared to both the distraction and control groups. Difficulty disengaging from pain‐related stimuli, as measured by the duration of the first fixation on sensory words, was found to moderate the relative efficacy of mindfulness versus distraction in terms of pain threshold and distress, but not tolerance. Those with difficulty disengaging from sensory pain words benefited less from the MIET. Duration of first fixation on sensory and affective pain words were highly correlated, and duration of first fixation on affective pain words also moderated the relative efficacy of MIET and distraction on threshold, but not distress.

Conclusions

These results show that a single brief session of a mindfulness task was sufficient to change an acute pain experience in comparison with a distraction task, and that those who disengaged quickly from pain words benefited most.

Significance

This study demonstrated the efficacy of a novel, exposure‐based mindfulness technique for pain tolerance and showed that those who disengaged easily from pain stimuli benefited most. This brief task could be clinically useful, particularly for those who are not overly focused on their pain symptoms.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CmJpAp
via IFTTT

Effects of astaxanthin on sensory‐motor function in a compression model of spinal cord injury: Involvement of ERK and AKT signalling pathway

Abstract

Background

Spinal cord injury (SCI) causes continuous neurological deficits and major sensory‐motor impairments. There is no effective treatment to enhance sensory‐motor function following SCI. Thus, it is crucial to develop novel therapeutics for this particular patient population. Astaxanthin (AST) is a strong antioxidant, anti‐inflammatory and anti‐apoptotic agent. In the present study, it was tested in a severe compression SCI model with emphasis on sensory‐motor outcomes, signalling pathway, along with other complications.

Methods

A severe SCI was induced by compression of the rat thoracic spinal cord with an aneurysm clip and treatment with AST or the vehicle was carried out, 30 min after injury. Behavioural tests including open field, von Frey, hot plate and BBB were performed weekly to 28 days post‐injury. Rats were assigned to measure blood glucose, weight and auricle temperature. Western blot and histological analysis also were performed at the same time points.

Results

AST decreased mechanical and thermal pain and also improved motor function performance, reduced blood glucose and auricle temperature increases and attenuated weight loss in SCI rats. Western blot analysis showed decreased activation of ERK1/2 and increased activation of AKT following AST treatment. The histology results revealed that AST considerably preserved myelinated white matter and the number of motor neurons following SCI.

Conclusion

Taken together, the beneficial effects of AST to improve sensory‐motor outcomes, attenuate pathological tissue damage and modulate ERK and AKT signalling pathways following SCI, suggest it as a strong therapeutic agent towards clinical applications.

Significance

Spinal cord injury (SCI) impairs sensory‐motor function and causes complications, which astaxanthin (AST) has the potential to be used as a treatment for. The present study investigates the effects of AST in a compression model of SCI with emphasis on sensory‐motor outcomes alongside other complications, histopathological damage and also related signalling pathways.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UAqVmZ
via IFTTT

Effects of glial glutamate transporter activator in formalin‐induced pain behaviour in mice

Abstract

Background

Nociceptive pain remains a prevalent clinical problem and often poorly responsive to the currently available analgesics. Previous studies have shown that astroglial glutamate transporter‐1 (GLT‐1) in the hippocampus and anterior cingulate cortex (ACC) is critically involved in pain processing and modulation. However, the role of astroglial GLT‐1 in nociceptive pain involving the hippocampus and ACC remains unknown. We investigated the role of 3‐[[(2‐Methylphenyl) methyl]thio]‐6‐(2‐pyridinyl)‐pyridazine (LDN‐212320), a GLT‐1 activator, in nociceptive pain model and hippocampal‐dependent behavioural tasks in mice.

Methods

We evaluated the effects of LDN‐212320 in formalin‐induced nociceptive pain model. In addition, formalin‐induced impaired hippocampal‐dependent behaviours were measured using Y‐maze and object recognition test. Furthermore, GLT‐1 expression and extracellular signal‐regulated kinase phosphorylation (pERK1/2) were measured in the hippocampus and ACC using Western blot analysis and immunohistochemistry.

Results

The LDN‐212320 (10 or 20 mg/kg, i.p) significantly attenuated formalin‐evoked nociceptive behaviour. The antinociceptive effects of LDN‐212320 were reversed by systemic administration of DHK (10 mg/kg, i.p), a GLT‐1 antagonist. Moreover, LDN‐212320 (10 or 20 mg/kg, i.p) significantly reversed formalin‐induced impaired hippocampal‐dependent behaviour. In addition, LDN‐212320 (10 or 20 mg/kg, i.p) increased GLT‐1 expressions in the hippocampus and ACC. On the other hand, LDN‐212320 (20 mg/kg, i.p) significantly reduced formalin induced‐ERK phosphorylation, a marker of nociception, in the hippocampus and ACC.

Conclusion

These results suggest that the GLT‐1 activator LDN‐212320 prevents nociceptive pain by upregulating astroglial GLT‐1 expression in the hippocampus and ACC. Therefore, GLT‐1 activator could be a novel drug candidate for nociceptive pain.

Significance

The present study provides new insights and evaluates the role of GLT‐1 activator in the modulation of nociceptive pain involving hippocampus and ACC. Here, we provide evidence that GLT‐1 activator could be a potential therapeutic utility for the treatment of nociceptive pain.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CmJnZj
via IFTTT

What do you expect? Catastrophizing mediates associations between expectancies and pain‐facilitatory processes

Abstract

Background

Pain expectancies are associated with altered pain sensitivity in individuals with chronic pain. However, little is known about the processes by which pain expectancies impact pain processing. This study assessed the association between pain expectancies and temporal summation (TS) of pain, and examined whether pain catastrophizing mediated this association.

Methods

In this cross‐sectional study, participants (437 chronic low back pain [CLBP] patients, 115 controls) completed self‐report measures of pain intensity, pain expectancies and pain catastrophizing before undergoing psychophysical pain‐testing procedures designed to assess mechanical TS of mechanical pain. Pearson's correlations examined the associations between study variables in CLBP patients and controls. Bootstrapping mediation analyses assessed the mediating role of pain catastrophizing on the association between pain expectancies and TS of pain.

Results

Temporal summation of pain was significantly associated with pain expectancies (r = 0.113) and pain catastrophizing (r = 0.171) in CLBP patients. Results of mediation analyses revealed that pain catastrophizing mediated the relationship between pain expectancies and TS of pain in CLBP patients (ab = 0.309, 95% CI = 0.1222–0.5604), but not in healthy controls (ab = −0.125, 95% CI = −0.5864 to 0.0244).

Conclusions

The findings from this study suggest that compared to controls, CLBP patients show increased sensitivity to mechanical pain procedures and enhanced pain‐facilitatory processing, proving further evidence for changes in central nervous system pain processing in CLBP patients. Our results also suggest that pain catastrophizing may be the mechanism by which pain expectancies are associated with TS of pain in CLBP patients.

Significance

Individuals with chronic low back pain who expect higher levels of pain and catastrophize about their pain are more likely to experience altered pain sensitivity. Our results point to catastrophizing as a mechanism of action through which psychological factors may operate and lead to the development and maintenance of chronic low back pain.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UCxMfW
via IFTTT

Propofol attenuates postoperative hyperalgesia via regulating spinal GluN2B‐p38MAPK/EPAC1 pathway in an animal model of postoperative pain

Abstract

Background

Total intravenous anesthesia with propofol has been shown to reduce postoperative pain in some clinical studies, but knowledge of its underlying analgesic mechanism remains limited. In this study, we compared the analgesic effects of propofol versus isoflurane in an animal model of postoperative pain and evaluated its underlying molecular mechanisms.

Methods

Plantar incision was made in the hind paws of rats under general anesthesia with 2.5% of inhalational isoflurane (isoflurane group) or intravenous infusion of propofol (1.5 mg kg−1 min−1, propofol group). Mechanical allodynia was assessed by paw withdrawal threshold before and after incision. Spinal dorsal horns (L3–L5) were harvested 1 hr after incision to assess the level of phosphorylated GluN2B, p38MAPK, ERK, JNK, and EPAC using Western blot and immunofluorescence.

Results

Mechanical allodynia induced by plantar incision peaked at 1 hr and lasted for 3 days after incision. It was significantly less in the propofol group compared with the isoflurane group in the first 2 hr following incision. The incision‐induced increases in phosphorylated GluN2B, p38MAPK, and EPAC1 were significantly reduced in the propofol group. The number of spinal dorsal neurons co‐expressed with EPAC1 and c‐Fos after the incision was significantly lower in the propofol group.

Conclusion

Propofol reduced pain responses in an animal model of postoperative pain and suppressed the spinal GluN2B‐p38MAPK/EPAC1 signaling pathway. Since the p38MAPK/EPAC pathway plays a critical role in the development of postoperative hyperalgesia, our results provide evidence‐based behavioral, molecular, and cellular mechanisms for the analgesic effects of propofol when used for general anesthesia.

Significance

These findings may provide a new mechanism for the postsurgical analgesic effect of propofol, which is particularly interesting during the subacute period after surgery as it is the critical period for the development of persistent postsurgical pain.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CmJlk9
via IFTTT

The type of sport matters: Pain perception of endurance athletes versus strength athletes

Abstract

Background

Studies assessing athletes’ pain sensitivity yield inconsistent data, which demonstrate either increased pain threshold and tolerance in athletes than controls or similar thresholds. This inconsistency may result from the variability in the type of sport practiced by the athletes and its effect on pain perception. For example, endurance athletes perform continuous intense exercise for prolonged durations, whereas strength athletes perform short bouts of extreme efforts. Consequently, endurance athletes may tolerate and modulate pain better than strength athletes. This hypothesis was tested by comparing pain perception of endurance athletes with that of strength athletes.

Methods

Subjects were 19 endurance athletes (triathletes), 17 strength athletes (weightlifters and throwers) and 17 non‐athlete controls. Quantitative measurements included heat‐pain threshold, heat‐pain tolerance, cold pressor pain ratings, temporal summation of pain (TSP) and conditioned pain modulation (CPM). Fear of pain and pain catastrophizing were also assessed.

Results

The two athlete groups had lower pain ratings than non‐athletes. However, strength athletes had higher heat‐pain threshold than endurance athletes, whereas endurance athletes had higher heat‐pain tolerance and stronger CPM than strength athletes and lower fear of pain levels. Longer training time correlated with TSP in endurance athletes but with CPM and heat‐pain tolerance in strength athletes.

Conclusions

Although athletes in general seem less responsive to noxious stimuli than non‐athletes, the type of sport differentially affects pain perception; whereas endurance‐based sport is associated with improved pain inhibition, strength‐based sport is associated with reduced pain sensitivity. These characteristics may be considered when sport is recommended for pain management.

Significance

This study shows that different sport types are associated with different characteristics of pain perception and modulation, as well as of thoughts towards pain.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UCGPxf
via IFTTT

Comparison of two neonatal pain assessment tools (Children and Infant’s Postoperative Pain Scale and the Neonatal Facial Coding System—Revised) and their relations to clinicians’ intuitive pain estimates

Abstract

Background

Many neonatal observational pain assessment tools are available. Their application in clinical settings, however, has been limited. A further difficulty for decision makers may be to choose among the variety of available tools the appropriate one(s) for their patients. Aims of the present study were (1) to compare two commonly cited neonatal pain assessment tools, the Neonatal Facial Coding System—Revised (NFCS‐R) and the Children and Infant’s Postoperative Pain Scale (CHIPPS), with regard to their psychometric qualities and (2) to explore intuitive clinicians’ ratings by relating them to the tools’ items.

Methods

Three coders applied both pain assessment tools to videos of 44 neonates who were videotaped while undergoing a painful and a stressful procedure. Clinicians rated the pain neonates experienced on a numerical rating scale. Analyses of variances and regression analyses were used to investigate whether tools could discriminate between the procedures and whether tools’ items were predictors of intuitive clinicians’ ratings.

Results

Interrater reliability, internal consistency and relative convergent validity were high for both assessment tools. Both tools discriminated between painful and stressful situations equally well. Roughly one third of variance in clinicians’ intuitive ratings could be explained by items of each tool, however, no single item was found to be a significant predictor.

Conclusions

Both pain assessment tools performed equally well regarding psychometric comparisons. Therefore, clinical utility needs to be considered when having to choose. Possibilities of improvement for both tools were identified. Cues clinicians base their intuitive pain judgements need to be further investigated.

Significance

Psychometric comparisons of neonatal assessment tools provide useful information that can help health care professionals to choose among tools and researchers to improve them. Both tools compared here performed psychometrically equally well. Their clinical utility, however, can be improved, for example by providing a manual (CHIPPS) and training opportunities.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CnE6kl
via IFTTT

Factors influencing the use of opioids for breakthrough cancer pain: A secondary analysis of the IOPS‐MS study

Abstract

Background

Controversies exist about the choice and the doses of opioid medication in breakthrough cancer pain (BTcP).

Methods

The aim was to assess factors influencing the use and the doses of opioids prescribed for BTcP. There was performed a secondary analysis of a national, multicentre study that involving 32 centres performed in patients having BTcP. Diagnosis of BTcP was based on a definite algorithm. Patients using opioids for background pain and for BTcP were selected. Average pain intensity and opioids used for background pain and BTcP, and adverse effects were assessed, as well as patient’s satisfaction and the grade of mucositis.

Results

The analysis was performed in 2,771 patients. Opioid doses given for BTcP were significantly associated with those given for background pain. No relationship between adverse effects and the use and the doses of opioids used for BTcP was found. Drugs and doses were not correlated to the grade of oral mucositis. Nasal fentanyl preparations provided the fastest meaningful pain relief in comparison with other fentanyl transmucosal preparations or morphine preparations (P = 0.000). The majority of patients were satisfied with opioid medications given for BTcP. Only 2.8% of patients reported adverse effects related to opioid medication used for BTcP. Age and gender were independently associated with dosages of some fentanyl products.

Conclusions

Opioids for BTcP were effective and safe in a large sample of cancer patients with different stages of disease. Doses of opioids proportional to doses used for background pain seem to guarantee both efficacy and safety.

Significance

The use of opioids for breakthough cancer pain was effective and safe in a large sample of advanced cancer patients recruited in different stages of disease and settings. Doses of opioids proportional to opioid doses used for background analgesia, seem to guarantee both effectiveness and safety.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UA11zX
via IFTTT

STarT Back Tool risk stratification is associated with changes in movement profile and sensory discrimination in low back pain: A study of 290 patients

Abstract

Background

Investigation of movement and sensory profiles across STarT Back risk subgroups.

Methods

A chronic low back pain cohort (n = 290) were classified as low, medium or high risk using the STarT Back Tool, and completed a repeated spinal bending task and quantitative sensory testing. Pain summation, time taken and the number of protective behaviours with repeated bending were measured. Sensory tests included two‐point discrimination, temporal summation, pressure/thermal pain thresholds and conditioned pain modulation. Subgroups were profiled against movement and sensory variables.

Results

The high‐risk subgroup demonstrated greater pain summation following repeated forward bending (< 0.001). The medium‐risk subgroup demonstrated greater pain summation following repeated backward bending (= 0.032). Medium‐ and high‐risk subgroups demonstrated greater forward/backward bend time compared to the low‐risk subgroup (= 0.001, = 0.005, respectively). Medium‐ and high‐risk subgroups demonstrated a higher number of protective behaviours per forward bend compared to the low‐risk subgroup (= 0.008). For sensory variables, only two‐point discrimination differed between subgroups, with medium‐ and high‐risk subgroups demonstrating higher thresholds (= 0.016).

Conclusions

This study showed altered movement characteristics and sensory discrimination across SBT risk subgroups in people with CLBP. Membership of the high SBT risk subgroup was associated with greater pain and disability levels, greater pain summation following repeated bending, slower bending times, a greater number of protective behaviours during forward bending, and a higher TPD threshold. Treatment outcomes for higher risk SBT subgroups may be enhanced by interventions specifically targeting movement and sensory alterations.

Significance

In 290 people with chronic low back pain movement profile and two‐point discrimination threshold differed across risk subgroups defined by the STarT Back Tool. Conversely, pain sensitivity did not differ across these subgroups. These findings may add further guidance for targeted care in these subgroups.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CnE4sJ
via IFTTT

Sweating disorders in mice with and without nerve lesions

Abstract

Background

Hypersensitivity and altered sweating are often present in neuropathy patients. Nerve lesions are known to produce sudomotor dysfunctions but also patients suffering from complex regional pain syndrome, CRPS1—a condition without a nerve lesion—present with sweating disorders.

Methods

Using proton nuclear magnetic resonance of sweat water, we quantified sweat output of mice suffering from a nerve lesion or a bone fracture without nerve lesion and correlated their sweating with behavioural paw hypersensitivity accessed in von Frey testings, water applications and weight‐bearing measured with an incapacitance metre.

Results

Lesioned animals sweat less and are hypersensitive compared to healthy controls, as expected. Fractured animals on the injured side sweat less acutely after the injury but more in the chronic phase. They are hypersensitive acutely as well as chronically after the fracture. These findings resemble human bone trauma patients in the acute phase and CRPS patients in the chronic phase.

Conclusions

Sweating disorders are present both in neuropathic animals and in those with a bone fracture without nerve lesions, and autonomic dysfunctions might be considered as an important component in the aetiology of neuropathies.

Significance

Sweat output changes in mice after bone trauma, potentially indicative of posttraumatic processes leading to CRPS in humans.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UyTnWu
via IFTTT

Anti‐hypersensitive effect of angiotensin (1‐7) on streptozotocin‐induced diabetic neuropathic pain in mice

Abstract

Background

We have recently reported that the spinal angiotensin (Ang) converting enzyme (ACE)/Ang II/AT1 receptor axis and downstream p38 MAPK phosphorylation are activated in streptozotocin (STZ)‐induced diabetic mice and lead to tactile hypersensitivity. Moreover, our previous results suggested that the intrathecal (i.t.) administration of Ang (1‐7), an N‐terminal fragment of Ang II, may attenuate the Ang II‐induced nociceptive behaviour through the inhibition of p38 MAPK phosphorylation via Mas receptors. Here, we investigated whether the i.t. administration of Ang (1‐7) can attenuate STZ‐induced diabetic neuropathic pain.

Methods

Tactile and thermal hypersensitivities were determined using the von Frey filament and Hargreaves tests, respectively. The protein expression of ACE2, Mas receptors and phospho‐p38 MAPK was measured by western blotting. Spinal ACE2 activity was determined using ACE2 activity assay kit.

Results

The i.t. administration of Ang (1‐7) significantly reduced the tactile and thermal hypersensitivities on day 14 after STZ injection, and these effects were significantly prevented by the Mas receptor antagonist A779. The expression of ACE2 and Mas receptors in the plasma membrane fraction of the lumbar dorsal spinal cord was both significantly decreased in STZ mice. Spinal ACE2 activity was also decreased while p38 MAPK phosphorylation was increased in the lumbar dorsal region of these mice. This phosphorylation was attenuated by the injection of Ang (1‐7), whose effect was reversed by A779.

Conclusions

Our data demonstrate that Ang (1‐7) attenuates STZ‐induced diabetic neuropathic pain and that this occurs through a mechanism involving spinal Mas receptors and he inhibition of p38 MAPK phosphorylation.

Significance

The ACE2/Ang (1‐7)/Mas receptor axis was down‐regulated in the spinal cord of STZ mice and the i.t. administration of Ang (1‐7) attenuated the STZ‐induced diabetic neuropathic pain via Mas receptors. Therefore, the activation of this axis could be an effective therapeutic target to alleviate the neuropathic pain in diabetic patients.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CnE2B7
via IFTTT

Amylin, a peptide expressed by nociceptors, modulates chronic neuropathic pain

Abstract

Background

Amylin is a calcitonin gene‐related peptide family member expressed by nociceptors. Amylin's expression is down‐regulated following nerve damage, and studies suggested it affects nociception. We aimed at clarifying amylin's effects on chronic neuropathic pain and investigating its site of action.

Methods

Chronic neuropathic pain was induced in rats by spared nerve injury (SNI) surgery. Mechanical allodynia/hyperalgesia and cold allodynia/hyperalgesia were assessed by the von Frey, pinprick, acetone and cold plate behavioural tests, respectively. Amylin, amylin‐receptor antagonist (AC187) or vehicle solutions were delivered chronically, by a subcutaneous (SC) mini‐osmotic pump, or acutely, by SC or intrathecal (IT) injections. Cellular and fibre markers were used to detect spinal cord alterations in SNI rats after chronic amylin administration.

Results

Continuous subcutaneous amylin administration aggravated cold allodynia in SNI animals, possibly via amylin‐receptors (AmyR) in supraspinal areas. Acute intrathecal administration of amylin attenuated mechanical hyperalgesia, whereas AC187 reduced mechanical allodynia, suggesting distinct roles of endogenous amylin and of pharmacological amylin doses when targeting spinal cord amylin receptors. Chronic amylin administration promoted c‐Fos activation only in the dorsal horn neurons of SHAM animals, suggesting a distinctive role of amylin in the activation of the spinal neuronal circuitry under neuropathic and physiological conditions. ERK1/2 phosphorylation increased in the dorsal horn neurons of SNI rats chronically treated with amylin. This ERK1/2 cascade activation may be related to amylin's effect on the aggravation of cold allodynia in SNI rats.

Conclusions

Amylin's nociceptive effects seem to depend on the treatment duration and route of administration by acting at different levels of the nervous system.

Significance

Amylin modulated neuropathic pain by acting at different levels of the nervous system. Whereas supraspinal areas may be involved in amylin's induced pronociception, modulation of spinal cord amylin receptors by endogenous or pharmacological amylin doses triggers both pro‐ and antinociceptive effects.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UEXq3H
via IFTTT

Standards for the diagnosis and management of complex regional pain syndrome: Results of a European Pain Federation task force

Abstract

Background

Complex regional pain syndrome is a painful and disabling post‐traumatic primary pain disorder. Acute and chronic complex regional pain syndrome (CRPS) are major clinical challenges. In Europe, progress is hampered by significant heterogeneity in clinical practice. We sought to establish standards for the diagnosis and management of CRPS.

Methods

The European Pain Federation established a pan‐European task force of experts in CRPS who followed a four‐stage consensus challenge process to produce mandatory quality standards worded as grammatically imperative (must‐do) statements.

Results

We developed 17 standards in 8 areas of care. There are 2 standards in diagnosis, 1 in multidisciplinary care, 1 in assessment, 3 for care pathways, 1 in information and education, 4 in pain management, 3 in physical rehabilitation and 2 on distress management. The standards are presented and summarized, and their generation and consequences were discussed. Also presented are domains of practice for which no agreement on a standard could be reached. Areas of research needed to improve the validity and uptake of these standards are discussed.

Conclusion

The European Pain Federation task force present 17 standards of the diagnosis and management of CRPS for use in Europe. These are considered achievable for most countries and aspirational for a minority of countries depending on their healthcare resource and structures.

Significance

This position statement summarizes expert opinion on acceptable standards for CRPS care in Europe.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CnE245
via IFTTT

Trends in the consumption of opioids for the treatment of severe pain in Europe, 1990–2016

Abstract

Background

Over the last decades, consumption of opioids for the treatment of pain increased steadily in the United States, Australia, and a few European countries. To date, no study has analysed time trends in opioid consumption across Europe.

Methods

We analysed data provided by International Narcotics Control Boards on the consumption of fentanyl, oxycodone, morphine, hydromorphone and pethidine in 40 European countries over the last decade. Trends in total opioid consumption from 1990 to 2016 in 22 selected European countries, the European Union (EU) as a whole, and, for comparison purpose, the United States, were analysed using the joinpoint regression analysis.

Results

In 2014–2016, opioid use was >10,000 defined daily doses for statistical purposes (s‐DDD) per 1,000,000 inhabitants die in Western/Northern countries, whereas it was <1000 s‐DDD in Southern/Eastern ones. In most European countries, opioid consumption increased to a great extent between 2004–2006 and 2014–2016; it rose from 6,477 to 8,967 s‐DDD (+38.4%) in the EU, and from 14,598 to 16,491 s‐DDD (+13%) in the United States. The increase in opioid use was steady since the early to mid‐1990s in most European countries and it slowed down after the mid‐ to late 2000s. In Denmark, Finland, France, Ireland, Switzerland, Poland and the EU, opioid use levelled off or declined over most recent years.

Conclusions

Consumption of opioid analgesics sharply increased in most of European countries since the early to mid‐1990s. This notwithstanding, in the mid‐2010s there was still a more than 10‐fold difference between the highest consumption in Western/Northern countries and the lowest one in Southern/Eastern countries.

Significance

This study provides an updated and comprehensive analysis of time trends and geographic variations in opioid consumption use across European countries over the last three decades.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UCGPgJ
via IFTTT

Too much or too little opioid use? A comment on Bosetti et al.

European Journal of Pain, Volume 23, Issue 4, Page 639-640, April 2019.

from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CnE1x3
via IFTTT

Issue Information

European Journal of Pain, Volume 23, Issue 4, Page 637-638, April 2019.

from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UEfgUr
via IFTTT

Body movements as pain indicators in older people with cognitive impairment: A systematic review

Abstract

Background and objective

Pain assessment tools for cognitively impaired older people, unable to self‐report pain, are commonly founded upon observation of pain behaviour, such as facial expressions, vocalizations and body movements. The scientific basis for claiming that body movements may indicate pain has not formerly been investigated in a systematic review. The objective was to explore research evidence for body movements being pain indicators in older people with cognitive impairment.

Data bases and data treatment

MEDLINE, EMBASE, CINAHL, PsycINFO and the Cochrane Library were searched systematically. Two researchers independently identified and consented on studies to be included. PRISMA statement for reporting systematic reviews was followed. Mixed Methods Appraisal Tool was used for critical evaluation of study quality.

Results

A total of 2,096 records from the literature searches were identified, and 17 quantitative and eight qualitative studies were included in the review, the studies mainly related to older people with dementia. Quality scores ranged from 50% to 100%. We combined 62 items of body movements into 13 similar or synonymous items, and criteria for evidence were defined. Strong evidence was found for restlessness (agitation), rubbing, guarding, rigidity and physical aggression as the behaviours frequently responded (increased or decreased) to pain provoking activities, painful procedures and/or pain medication.

Conclusions

Among 13 categories of body movements, we found five with strong and five with moderate evidence of validity. As few items were typically included in many studies reflecting criterion validity, all should be included in future studies of patients with different characteristics, location and duration of pain.

Significance

Pain assessment tools for older people with cognitive impairment or dementia should include valid pain behaviour items. Our review shows strong scientific evidence for the following body movements indicating pain: restlessness (agitation), rubbing, guarding, rigidity and physical aggression.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CnE101
via IFTTT

Standards for the management of cancer‐related pain across Europe—A position paper from the EFIC Task Force on Cancer Pain

Abstract

Background and objective

Pain is a common symptom in patients who survive cancer and in those who live with progressive advanced disease. Evidence from meta‐analyses suggests that pain remains poorly controlled for a large proportion of patients; barriers to good management include poor assessment of pain, inadequate support for patient self‐management and late or inadequate access to strong opioid analgesia in those with advanced disease.

Methods

The European Pain Federation (EFIC) established a Task Force in 2017 which convened a European group of experts, drawn from a diverse range of relevant clinical disciplines, to prepare a position paper on appropriate standards for the management of cancer‐related pain. The expert panel reviewed the available literature and made recommendations using the GRADE system to combine quality of evidence with strength of recommendation. The panel took into account the desirable and undesirable effects of the management recommendation, including the cost and inconvenience of each when deciding the recommendation.

Results and conclusions

The 10 standards presented are aimed to improve cancer pain management and reduce variation in practice across Europe. The Task Force believes that adoption of these standards by all 37 countries will promote the quality of care of patients with cancer‐related pain and reduce unnecessary suffering.

Significance

Pain affects up to 40% of cancer survivors and affects at least 66% of patients with advanced progressive disease, many of whom experience poor pain control. These 10 standards are aimed to improve cancer pain management, promote the quality of care of patients and reduce variation across Europe.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2UyTi58
via IFTTT

Mechanisms of spinal cord stimulation for the treatment of pain: Still in the dark after 50 years

Abstract

Background and Objective

Despite the value of spinal cord stimulation (SCS) in treating some patients with focal neuropathic pain, technological advances in stimulator design and treatment protocols have not correlated with significant improvements in clinical outcomes. This may be because incomplete understanding of the mechanisms underlying SCS precludes improvement in clinical efficacy. In this brief review, we (a) review phenomenological effects of SCS, (b) review the literature on proposed spinal sites of action of SCS and (c) propose a novel hypothesis of mechanism of action.

Results

Dorsal columns, dorsal roots and dorsal horns have each been proposed as spinal sites of action of SCS. We suggest that evidence in favour of the dorsal columns or dorsal roots as the primary mediators of SCS is weak and propose that the dorsal horn is the crucial site of action. Furthermore, we hypothesize that, based on their location, and neurochemical and morphological properties, dorsal horn islet cells may mediate the effects of SCS.

Conclusions

The precise spinal mechanisms of action of SCS are still unknown. Dorsal horn islet cells have properties that position them to play a key role in analgesic effects of electrical stimulation. Understanding the mechanisms responsible for positive SCS effects are needed for successful translation into clinical dividends.

Significance

We review possible spinal mechanisms of action of spinal cord stimulation for neuropathic pain, proposing that direct modulation of dorsal horn neurons is crucial. We suggest that mechanistic insights are needed for translation into more favourable clinical outcomes.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2CnDZoV
via IFTTT

Thursday, March 14, 2019

Lymphoedema of lower limbs in systemic lupus erythematosus

A 36 year old woman presented with two weeks of bilateral widespread swelling, weakness, numbness, and redness of the legs, three months of knee joint pain, and a malar rash (fig...


from Latest headlines from BMJ https://ift.tt/2JdrlyN
via IFTTT

Robotic assisted Shoulder Rehabilitation Therapy Effectively Improved Post-stroke Hemiplegic Shoulder Pain: A Randomized Controlled Trial

Publication date: Available online 13 March 2019

Source: Archives of Physical Medicine and Rehabilitation

Author(s): Min-Su Kim, Sung Hoon Kim, Se-Eung Noh, Heui Je Bang, Kyoung-Moo Lee

Abstracts
Objective

The purpose of this study was to investigate the therapeutic effects of a newly developed shoulder robot on post-stroke hemiplegic shoulder pain

Design

Prospective, single-blind randomized controlled trial.

Setting

Inpatient department of a tertiary university hospital.

Participants

Hemiplegic shoulder pain patients (n=38) were consecutively recruited and randomly assigned to an intervention or control group.

Interventions

A newly developed robot was designed to perform joint mobilization and stretching exercises with patients lying in the supine position. Conventional physical therapy directed at both improving upper extremity mechanics and reducing neurologic injury was performed twice per day in both groups. In the intervention group, additional robotic assisted shoulder rehabilitation therapy was administered for 30 minutes per day, five times per week for 4 weeks.

Main outcome measures

The visual analogue scale was the primary outcome, and the pain-free passive range of motion of the shoulder joint, the Korean version of the Shoulder Disability Questionnaire, and ultrasonographic grades were the secondary outcomes. The outcomes were evaluated at baseline (T0), post-intervention (T1), and a 4-week follow-up (T2).

Results

Significant time and group interaction effects were found on the visual analogue scale, in the abduction passive range of motion, and on the Shoulder Disability Questionnaire (F2,33=16.384, p=0.002; F2,33=10.609, p=0.012; F2,33=32.650, p=0.008, respectively). Significantly higher improvements in these outcome measures were observed in the intervention group than in the control group at T1 after post-hoc analysis (p<0.05, all). These improvements were sustained at T2 when the intervention group was compared with the control group (p<0.05, all).

Conclusions

A prototype shoulder rehabilitation robot as an adjuvant therapy improves hemiplegic shoulder pain and self-reported shoulder-related disability.



from ScienceDirect Publication: Archives of Physical Medicine and Rehabilitation https://ift.tt/2FcJCIl
via IFTTT

Wednesday, March 13, 2019

Neurophysiology and genetics of burning mouth syndrome

Abstract

Background and aims

Neuropathic mechanisms are involved in burning mouth syndrome (BMS), and variation of the dopamine D2 receptor (DRD2) gene contributes to experimental pain perception. We investigated whether neurophysiologic findings differ in BMS patients compared to healthy controls, and whether 957C>T polymorphism of the DRD2 gene influences thermal sensitivity or pain experience in BMS.

Methods

Forty‐five BMS patients (43 women), mean age 62.5 years, and 32 healthy controls (30 women), mean age 64.8 years, participated. Patients estimated pain intensity, interference, suffering and sleep with Numeric Rating Scale. Blink reflex tests of the supraorbital (SON), mental (MN) and lingual (LN) nerves, and thermal quantitative sensory testing were done. The results were analysed with ANOVA. DRD2 gene 957C>T polymorphism was determined in 31 patients, and its effects on neurophysiologic and clinical variables were analysed.

Results

Cool (p = 0.0090) and warm detection thresholds (p = 0.0229) of the tongue were higher in BMS patients than controls. The stimulation threshold for SON BR was higher in patients than in controls (p = 0.0056). The latencies of R2 component were longer in BMS patients than in controls (p = 0.0005) at the SON distribution. Habituation of SON BR did not differ between the groups. The heat pain thresholds were highest (p = 0.0312) in homozygous patients with 957TT, who also reported most interference (p = 0.0352) and greatest suffering (p = 0.0341). Genotype 957CC associated with sleep disturbances (p = 0.0254).

Conclusions

Burning mouth syndrome patients showed thermal hypoesthesia within LN distribution compatible with small fibre neuropathy. The DRD2 957C>T genotype influences perception and experience of BMS pain.

Significance

The results confirm earlier findings of neuropathic pain in BMS. The DRD2 957 C>T genotype influences perception and experience of clinical pain in BMS.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2TKuIRH
via IFTTT

Lumbar range of motion in chronic low back pain is predicted by task‐specific, but not by general measures of pain‐related fear

Abstract

Background

Most studies fail to show an association between higher levels of pain‐related fear and protective movement behaviour in patients with chronic low back pain (CLBP). This may be explained by the fact that only general measures of pain‐related fear have been used to examine the association with movement patterns. This study explored whether task‐specific, instead of general measures of pain‐related fear can predict movement behaviour.

Methods

Fifty‐five patients with CLBP and 54 healthy persons performed a lifting task while kinematic measurements were obtained to assess lumbar range of motion (ROM). Scores on the Photograph Daily Activities Series‐Short Electronic Version (PHODA‐SeV), Tampa Scale for Kinesiophobia and its Activity Avoidance and Somatic Focus subscales were used as general measures of pain‐related fear. The score on a picture of the PHODA‐SeV, showing a person lifting a heavy object with a bent back, was used as task‐specific measure of pain‐related fear.

Results

Lumbar ROM was predicted by task‐specific, but not by general measures of pain‐related fear. Only the scores on one other picture of the PHODA‐SeV, similar to the task‐specific picture regarding threat value and movement characteristics, predicted the lumbar ROM. Compared to healthy persons, patients with CLBP used significantly less ROM, except the subgroup with a low score on the task‐specific measure of pain‐related fear, who used a similar ROM.

Conclusions

Our results suggest to use task‐specific measures of pain‐related fear when assessing the relationship with movement. It would be of interest to investigate whether reducing task‐specific fear changes protective movement behaviour.

Significance

This study shows that lumbar range of motion in CLBP is predicted by task‐specific, but not by general measures of pain‐related fear. This suggests that both in clinical practice and for research purposes, it might be recommended to use task‐specific measures of pain‐related fear when assessing the relationship with movement behaviour. This may help to disentangle the complex interactions between pain‐related fear, movement and disability in patients with CLBP.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2J8ZXln
via IFTTT

Comparing the effectiveness of integrating ergonomics and motor control to conventional treatment for pain and functional recovery of work‐related neck–shoulder pain: A randomized trial

Abstract

Background

Work‐related neck and shoulder pain (WRNSP) is highly prevalent among patients who seek physiotherapy treatment. Clinicians may tend to focus on teaching home exercises and provide general advice about workplace improvement. The present study investigates the short‐ and long‐term impact of an intervention approach that emphasizes on integrating the motor control re‐education with ergonomic advice.

Methods

Participants diagnosed with WRNSP (n = 101) were randomly assigned into two groups in this randomized controlled trial. The Ergo‐motor Group (EM, n = 51) received an integrated intervention with ergonomic advice/modifications and motor control training individualized for each participant based on their specific work demands. Control Group (CO, n = 50) received treatment for pain relief and general exercises of their necks at a designated physiotherapy clinic. Neck pain intensity and functional outcome measures were assessed before, immediately and 1‐year after the 12‐week intervention programmes. Global Rating of Change Score was used to evaluate the perceived recovery at 1‐year follow‐up.

Results

Both groups reported significant reductions in pain and functional disability scores at post‐intervention (EM, n = 44; CO, n = 42) and 1‐year follow‐up (EM, n = 40; CO, n = 38); however, no significant between‐group differences were found (p > 0.05). Significantly higher rating in global recovery score was reported in EM group at 1‐year follow‐up (p < 0.05).

Conclusions

Intervention integrating ergonomic advice/modification with motor control exercise was found to be equally effective as pain relief and general exercise for pain and functional recovery. However, at 1‐year follow‐up, such integrated approach resulted in significantly better global recovery perceived by people with WRNSP.

Significance

Integrating ergonomic intervention and motor control training achieved similar reduction in pain and functional outcomes compared to conventional physiotherapy at post‐intervention and at 1‐year follow‐up, for patients with moderate level of work‐related neck–shoulder pain and mild degree of functional disability. The Ergo‐motor Group reported significantly better perceived overall recovery at 1‐year follow‐up.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2TNK8Vo
via IFTTT

Comments on the paper by Nielsen et al. entitled “Intraoperative S‐ketamine for the reduction of opioid consumption and pain one year after spine surgery: A randomized clinical trial of opioid‐dependent patients”

Abstract

After reading the article(Nielsen et al., 2019) presented in the latest issue, we reviewed another related article(Nielsen et al., 2017) published by the same author in 2017. The two articles were based on the same clinical trial (NCT02085577) assessing the effect of intraoperative ketamine on opioid consumption and pain after spine surgery in opioid‐dependent patients. In the earlier article, authors found that morphine consumption, both perioperatively and at 6 months after surgery, was reduced in the ketamine group compared with the placebo group.

This article is protected by copyright. All rights reserved.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2JdpSbz
via IFTTT

A Systematic Review and Meta‐analysis of Memantine for the Prevention or Treatment of Chronic Pain

Abstract

Background and Objective

N‐methyl‐D‐aspartate (NMDA) receptors are involved in pain signalling and neuroplasticity. Memantine has been shown to have analgesic properties in pre‐clinical and small clinical studies. We conducted a systematic review and meta‐analysis to assess the efficacy of memantine to prevent or reduce chronic pain.

Databases and Data Treatment

MEDLINE, EMBASE, and CENTRAL databases were searched for comparative trials using memantine, either against placebo or active medications, for chronic pain in adults. Pain relief was considered our primary outcome. Meta‐analyses were conducted if outcomes were reported in two or more studies. Outcomes were reported as mean differences (MD) or risk ratios (RR) with 95% confidence intervals (CI). Quality was assessed using the GRADE approach.

Results

Among 454 citations, 15 studies were included with populations predominantly consisting of neuropathic conditions and fibromyalgia. Overall, we observed unclear reporting of randomization and allocation methods, apart from potential for publication bias. Among the 11 studies looking at chronic pain treatment, the difference in end pain score with memantine was not significant: MD=–0.58 units (95%CI –1.31, 0.14); I2=82% (low quality). In two surgical studies using memantine for pain prevention, memantine decreased pain intensity: MD=–1.02 units (95%CI –1.38, –0.66); I²=0%. Dizziness was significantly more common with memantine: RR = 4.90 (95%CI 1.26, 18.99); I²=52% (moderate quality).

Conclusion

The current evidence regarding the use of memantine for chronic pain is limited and uncertain. Despite its potential, pain relief achieved in clinical studies is small and is associated with an increase in dizziness.

Significance statement

Despite a sound rationale, the benefit of using memantine for chronic pain is unclear. Our systematic review and meta‐analysis shows that memantine may have the potential to decrease pain. However, it can also increase common adverse effects. Considering the small number of studies with potential for bias and inconclusive evidence, there was low to very low certainty. Hence, no clear recommendations can be made about its routine clinical use until larger and more definitive studies are conducted.

This article is protected by copyright. All rights reserved.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2TNK7Rk
via IFTTT

Opioid use after hip fracture surgery: A Danish nationwide cohort study from 2005‐2015

Abstract

Background

There is currently a knowledge gap regarding persistent opioid use after hip fracture surgery. Thus, opioid use within a year after hip fracture surgery in patients with/without opioid use before surgery was examined.

Methods

This population‐based cohort study included all patients (aged≥65) undergoing primary hip fracture surgery in Denmark (2005‐2015) identified from the Danish Multidisciplinary Hip Fracture Database. Opioid use was assessed from The Danish National Health Service Prescription Database as redeemed prescriptions. The proportion of patients with ≥1 opioid prescription was computed within six‐month before surgery and each of four three‐month periods (quarters) after surgery, among patients alive first day in each period. Proportion differences (95%CI) were calculated for each quarter compared to before surgery. Proportions were calculated for users and non‐users before surgery, including initiators after first quarter.

Results

This study included 69,456 patients. Proportion differences of opioid users were 35.0 (95%CI 34.5‐35.5), 7.0 (95%CI 6.5‐7.5), 2.9 (95%CI 2.4‐3.4), and 1.4 percentage‐points (95%CI 0.9‐1.9) the four quarters after surgery compared to before. Among opioid non‐users before surgery, 54.7% (95%CI 54.3‐55.1) 21.8% (95%CI 21.4‐22.2), 17.8% (95%CI 17.4‐18.2), and 16.8% (95%CI 16.4‐17.2) were opioid users in 1st‐4th quarter after surgery. However, 8.5% (95%CI 8.2‐8.7) of the non‐users before surgery in 4th quarter initiated opioid use more than a quarter after surgery.

Conclusions

The proportion of opioid users increased after hip fracture surgery and was 1.4 percentage‐points increased in fourth quarter compared to before. Of opioid non‐users before surgery, 16.8% were opioid users fourth quarter after surgery.

This article is protected by copyright. All rights reserved.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2JceOeU
via IFTTT

Assessment of experimental orofacial pain, pleasantness and unpleasantness via standardised psychophysical testing

Abstract

Background

Somatosensory assessment within the orofacial region may be performed using highly standardised quantitative sensory testing (QST). However, the function of the C tactile (CT) afferent, a nerve fibre linked to the perception of pleasant touch, is usually not evaluated. Furthermore, the perception of unpleasantness is also rarely assessed; a dimension not only limited to a painful experience. Therefore, the primary aim was to apply standardised QST stimuli as well as standardised pleasant stimuli and evaluate their potential capacity for evocation of perceived pain, pleasant and unpleasant sensations in the facial region.

Methods

Twenty‐one female participants underwent QST as per the protocol derived from the German Research Network on Neuropathic Pain. For the first time, two modified protocols were used to investigate stimuli for perceived pleasantness and unpleasantness.

Results

Thermal stimuli provided separate thresholds for each sensation. From certain mechanical stimuli (e.g. vibration), overlap between the perceived sensations of pleasantness and unpleasantness were identified. It was not possible to evoke only an unpleasant sensation without a painful contribution, and both these sensations increased significantly when utilising an increasing pinprick force (p < 0.011). Between dynamic stimuli, the brush was rated as significantly more pleasant than the cotton wool tip (p = 0.015). A quadratic model provided the best fit for velocity against mean pleasantness ratings (R2 = 0.62 ± 0.08), supporting previous CT afferent literature to some extent.

Conclusion

Stimuli were generally not isolated to one sensation, highlighting the multidimensional construct of stimulus perception, and the need for scales to capture this.

This article is protected by copyright. All rights reserved.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2TKuFFv
via IFTTT

Cold‐evoked potentials versus contact‐heat evoked potentials ‐ methodological considerations and clinical application

Abstract

Background

Previous studies investigated cold‐evoked potentials (CEPs) for the assessment of the integrity of cold mediating A‐delta fibres and the spino‐thalamic tract. Nevertheless, several methodological questions remained unanswered to proceed to clinical application. How do latencies and amplitudes vary between CEPs and contact heat evoked potentials (CHEPs)? Are there differences between variable and fixed thermode positions or between glabrous and hairy skin? Are CEPs recordable in patients with abnormal cold processing?

Methods

16 healthy subjects were tested with CEPs and CHEPs at the face, hand, and foot. Variable and fixed thermode positions, hairy and glabrous skin were compared. Three patients with abnormal cold processing were tested with CEPs and quantitative sensory testing.

Results

Compared to CEPs, CHEPs latencies were significantly longer at all locations, amplitudes were significantly larger at the face and the hand whilst comparable at the foot. CEPs and CHEPs did not differ significantly between variable and fixed thermode positions using inter stimulus intervals of 8‐12 seconds. CEP latencies were increased by around 20% at the glabrous skin. Patients with known abnormal cold processing (central pain, polyneuropathy, Fabry's disease) showed increased N2 latencies as compared to normal controls.

Conclusions

Inter stimulus intervals of 8‐12s allow the use of a fixed thermode position for reliable CEPs/CHEPs recording. Hairy skin stimulation results in faster latencies as compared to glabrous skin, without influencing EP‐amplitudes. In patients with abnormal cold processing, CEPs are recordable and increased latencies may be expected as compared to healthy controls and the healthy contralateral side.

This article is protected by copyright. All rights reserved.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2JaeCwx
via IFTTT

Does my pain affect your disgust? Cross‐modal influence of first‐hand aversive experiences in the appraisal of others’ facial expressions

Abstract

Background

Embodied models of social cognition argue that others’ affective states are processed by re‐enacting a sensory‐specific representation of the same state in the observer. However, neuroimaging studies suggest that a reliable part of the representation shared between self and others is supramodal, and relates to dimensions such as unpleasantness or arousal, common to qualitatively‐different experiences. Here we investigated whether representations of first‐hand pain and disgust influenced the subsequent evaluation of facial expressions in modality‐specific fashion, or in terms of unpleasantness or arousal.

Methods

30 volunteers were subjected to thermal painful and olfactory disgusting events, and subsequently were asked to classify computer‐generated faces expressing pain (characterized by high unpleasantness and arousal), disgust (high unpleasantness and low arousal), surprise (low unpleasantness and high arousal), and hybrid combinations thereof.

Results

Thermal and olfactory events were associated with comparable unpleasantness ratings and heart rate (but stronger galvanic response was found for painful temperatures). Furthermore, we found that the appraisal of facial expressions was biased by the prior stimulus, with more frequent pain classifications following thermal stimuli, and more frequent disgust classifications following olfactory stimuli. Critically, this modulation was cross‐modal in nature, as each first‐hand stimulation influenced in comparable fashion facial traits diagnostic of both pain and disgust, without instead generalizing to features of surprise.

Conclusion

Overall, these data support the presence of shared coding between one's aversive experiences and the appraisal of others’ facial responses, which is best describable as supramodal representation of the unpleasantness of the experience.

This article is protected by copyright. All rights reserved.



from Wiley: European Journal of Pain: Table of Contents https://ift.tt/2TKuE4p
via IFTTT

Thursday, March 7, 2019

[Editorial] Cardiology's problem women

Asked to describe a typical heart attack, most people (including most doctors), would describe a man with crushing chest pain, probably with a background history of hypertension. But this traditional teaching, it turns out, is only telling us half the story. Cardiovascular disease is also the leading cause of death in women globally and, in the USA, leads to a similar number of deaths in men and women. The failure to recognise the prevalence of heart disease in women and the different set of symptoms in women (feeling generally unwell or unexplained weakness) during a heart attack contribute to delays in women seeking help and the loss of vital time in a cardiovascular emergency.

from The Lancet https://ift.tt/2SRBGjc
via IFTTT