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Background: Pain, the primary complaint in rheumatoid arthritis (RA), is multifaceted, and may be driven by inflammatory disease activity and central sensitisation. We aimed to ascertain what proportion of RA pain severity is explained by markers of inflammation and quantitative sensory testing (QST) indices of central sensitisation., Methods: This was a cross-sectional analysis of data from individuals with clinically active RA. Pain severity was assessed using numerical rating scales and inflammation via 28-joint Disease Activity Score (DAS28) and Ultrasound (Greyscale, Power Doppler). Pain sensitivity was assessed by 'static' (tibialis anterior or brachioradialis pressure pain detection threshold-PPT-TA/PPT-BR) and 'dynamic' (temporal summation-TS, conditioned pain modulation-CPM) QST. Bivariate associations used Spearman's correlation coefficients, and multivariable linear regression models determined relative contributions to pain severity., Results: In bivariate analyses of N = 96 (age 65 ± 10y, 77% females) people with RA, pain severity was significantly associated with inflammation indices (r = 0.20 to 0.55), and CPM (r=-0.26). In multivariable models that included TS, CPM, age, sex, and body mass index, inflammation indices remained significantly associated with pain severity. Multivariable models explained 22 to 27% of pain variance. Heterogeneity was apparent for associations with pain between subscores for pain now, strongest or average over the past 4-weeks., Conclusions: In individuals with clinically active RA, markers of inflammatory disease activity best explain RA pain with only marginal contributions from QST indices of central sensitisation. Although inflammation plays a key role in the experience of RA pain, the greater proportion of pain severity remains unexplained by DAS28 and ultrasound indices of inflammation., (© 2024. The Author(s).)

This systematic review and meta-analysis examined the evidence for altered central pain processing in people with nontraumatic neck pain and the relationship among central pain processing, demographics, and pain-related characteristics. Case-control studies reporting measures of altered central pain processing using quantitative sensory testing were reviewed. Standardized mean differences (SMDs) and 95% confidence intervals between people with nontraumatic neck pain and controls were calculated. Meta-analysis was performed using random-effects models when appropriate. Associations between SMDs with demographics and pain-related characteristics were explored on a study level using metaregression. Twenty-six studies were eligible with 25 included for meta-analysis. Meta-analysis demonstrated mechanical hyperalgesia at remote nonpainful sites in the full sample (sample size [n] = 1305, SMD = -0.68) and in the subgroup with moderate/severe disability (n = 165, SMD = -0.86; moderate-quality evidence). Metaregression indicated that remote mechanical hyperalgesia was negatively associated with age (R 2  = 25.4%, P = 0.031). Very low- to low-quality evidence of remote cold and heat hyperalgesia and dysfunctional conditioned pain modulation were identified. This review suggests that altered central pain processing is present in people with nontraumatic neck pain and may be associated with disability levels and age. PERSPECTIVE: This review found moderate-quality evidence of mechanical hyperalgesia at remote nonpainful sites in patients with nontraumatic neck pain compared with controls, indicating altered central pain processing. However, more studies are needed to confirm findings from dynamic quantitative sensory testing., (Copyright © 2020 United States Association for the Study of Pain, Inc. Published by Elsevier Inc. All rights reserved.)

Background/objectives: Chronic pancreatitis (CP) pain is challenging to treat. Treatment selection is hampered by there being no validated pain assessment tool that accounts for the complexity of CP pain and its underlying mechanisms. This study aims to develop a comprehensive pain assessment tool (COMPAT) specific for CP, evaluate its face validity with experts and patients and test it with a pilot cohort of patients., Methods: COMPAT was developed from existing pain assessment tools and a literature review. Face validity was conducted by pancreatologists and CP patients using an item-content validity index for importance, relevance and clarity. Subsequent revisions were made to COMPAT. A pilot cohort of CP patients tested COMPAT., Results: COMPAT was developed and covered all important aspects of CP pain. Experts and CP patients reported that 70% of questions were important and relevant to CP pain. Most experts were willing to use COMPAT in clinic, ward/hospital and research settings. The most common location of pain was the epigastrium and food was the most important trigger. Pain Pattern C (constant background pain with pain attacks), had significantly higher frequency of pain attacks, higher opioid use, and affective descriptors of pain than Pattern A (pain attacks with no background pain)., Conclusions: COMPAT has high face validity and met with high acceptance. CP patients successfully self-reported their pain with COMPAT. The results reveal many differences in the CP pain within the pilot cohort, which may reflect different mechanisms of pain. A larger prospective cohort study is planned to further validate COMPAT., (Copyright © 2017 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

Background: Patients with chronic pancreatitis (CP) frequently report chronic abdominal pain that adversely impacts their quality of life. Assessment of pain in CP is required for clinical management and clinical studies. International consensus guidelines recognized a lack of specific and validated pain assessment tools for CP. Therefore, the aim of this systematic review is to identify and compare all clinical studies that assessed pain in the context of a treatment for pain in CP., Methods: A systematic literature search was performed in PubMed, Cochrane Library and Ovid MEDLINE. The search identified all intervention studies for pain in CP and the pain assessment tools used based on pre-defined inclusion and exclusion criteria., Results: Of 341 articles identified, 137 studies were included. Pain assessment tools were both general and CP-specific. The latter were used in only 22 (16%) studies. Despite recommendations the aspects of pain assessed were limited and variable between tools. Validation of these tools in CP patients was limited to quality of life measures. None of the pain assessment tools evaluated duration of pain and postprandial pain., Conclusions: There are no published pain assessment tools for CP that includes all relevant aspects of pain. There is the need to develop a comprehensive and validated pain assessment tool for patients with CP to standardised pain assessment, identify likely underlying pain mechanisms, help select appropriate treatments, report outcomes from interventions, improve clinical communication and aid the allocation of patients to clinical trials., (Copyright © 2016 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

Purpose: To translate and cross-culturally adapt the English version of the Central Sensitisation Inventory (CSI) into Thai (CSI-Thai) and to evaluate its psychometric properties in individuals with chronic non-specific neck pain. Materials and methods: Cross-cultural translation and adaptation of the CSI were performed according to standard guidelines. A total of 340 participants were invited to complete the CSI-Thai, Visual Analogue Scale (pain intensity), Neck Disability Index, Fear-Avoidance Beliefs Questionnaire, Pain Catastrophising Scale (PCS), and Short Form-36. Psychometric evaluation included confirmatory factor analysis, internal consistency, test-retest reliability, agreement, and construct validity. Results: Dimensionality analyses indicated that a bifactor model, comprising one general factor plus four orthogonal factors, fit the CSI structure better than unidimensional and the four-factor models. The general factor showed substantial reliability (Cronbach α=0.91, Omega ω=0.94, and omega hierarchical x-h=0.91). The intraclass correlation coefficient was 0.90, representing excellent stability over a 48 h interval. Moderate-to-strong correlations and acceptable-to-excellent discriminations were found between the CSI-Thai and all questionnaires. The exception was the PCS (no correlation and discrimination). The standard error of measurement and minimal detectable change of the CSI-Thai were 2.33 and 6.47, respectively. Conclusions: The translation and cross-cultural adaptation of the CSI-Thai were successful, with satisfactory reliability and construct validity. [ABSTRACT FROM AUTHOR]

Background: Experienced assessors show good intra-rater reproducibility (withinsession and between-session agreement and reliability) when using an algometer to determine pressure pain thresholds (PPT). However, it is unknown whether novice assessors perform equally well. This study aimed to determine within and between-session agreement and reliability of PPT measurements performed by novice assessors and explored whether these parameters differed per assessor and algometer type. Methods: Ten novice assessors measured PPTs over four test locations (tibialis anterior muscle, rectus femoris muscle, extensor carpi radialis brevis muscle and paraspinal muscles C5-C6) in 178 healthy participants, using either a Somedic Type II digital algometer (10 raters; 88 participants) or a Wagner Force Ten FDX 25 digital algometer (nine raters; 90 participants). Prior to the experiment, the novice assessors practiced PPTs for 3 h per algometer. Each assessor measured a different subsample of ~9 participants. For both the individual assessor and for all assessors combined (i.e., the group representing novice assessors), the standard error of measurement (SEM) and coefficient of variation (CV) were calculated to reflect within and between-session agreement. Reliability was assessed using intraclass correlation coefficients (ICC1,1). Results: Within-session agreement expressed as SEM ranged from 42 to 74 kPa, depending on the test location and device. Between-session agreement, expressed as SEM, ranged from 36 to 76 kPa and the CV ranged from 9-16% per body location. Individual assessors differed from the mean group results, ranging from -55 to +32 kPa or from -9.5 to +6.6 percentage points. Reliability was good to excellent (ICC1,1: 0.87 to 0.95). Results were similar for both types of algometers. Conclusions: Following 3 h of algometer practice, there were slight differences between assessors, but reproducibility in determining PPTs was overall good. [ABSTRACT FROM AUTHOR]

The pathophysiology of fibromyalgia (FM) is related to central sensitisation (CS) to pain. Algometry allows assessing CS based on dynamic evoked pain. However, current algometrýs protocols require optimising, unifying and updating. 1) identify the dynamic pain measures used most frequently to effectively assess CS processes in FM, and 2) consider the future of the algometry assessing CS in these patients. Cochrane Collaboration guidelines and PRISMA statements were followed. The protocol was registered in PROSPERO database (ID: CRD42021270135). The selected articles were evaluated using the Cochrane risk of bias (ROB) assessment tool. The PubMed, Scopus, and Web of Science databases were searched. Thirty-four studies were selected, including measures such as temporal summation of pain (TSP), aftersensations (AS), spatial summation of pain (SSP), the noxious flexion reflex (NFR) threshold, conditioned pain modulation (CPM), cutaneous silent period (CuSP), and slowly repeated evoked pain (SREP); and evoked pain combined with neuroimaging. Each measure offered various advantages and limitations. According to ROB, 28 studies were of low quality, 3 of moderate quality, and 3 of high quality. Several pain indicators have been demonstrated to successfully examine CS involvement in FM in the last years. Algometry, especially when it involves diverse body sites and tissues, might provide further insight into (1) the evaluation of psychological factors known to influence pain experience, (2) new dynamic pain indicators, and (3) the simultaneous use of certain neuroimaging techniques. Further research clarifying the mechanisms underlying some of these measures, and homogenisation and optimisation of the algometrýs protocols, are needed. Algometry allows for assessing Central Sensitisation by applying dynamic evoked pain. The future of algometry could relapse in its combination with neuroimaging. Recently-emerged pain indicators should be considered for algometrýs new protocols. [ABSTRACT FROM AUTHOR]

Background Experienced assessors show good intra-rater reproducibility (within-session and between-session agreement and reliability) when using an algometer to determine pressure pain thresholds (PPT). However, it is unknown whether novice assessors perform equally well. This study aimed to determine within and between-session agreement and reliability of PPT measurements performed by novice assessors and explored whether these parameters differed per assessor and algometer type. Methods Ten novice assessors measured PPTs over four test locations (tibialis anterior muscle, rectus femoris muscle, extensor carpi radialis brevis muscle and paraspinal muscles C5-C6) in 178 healthy participants, using either a Somedic Type II digital algometer (10 raters; 88 participants) or a Wagner Force Ten FDX 25 digital algometer (nine raters; 90 participants). Prior to the experiment, the novice assessors practiced PPTs for 3 h per algometer. Each assessor measured a different subsample of ~9 participants. For both the individual assessor and for all assessors combined (i.e., the group representing novice assessors), the standard error of measurement (SEM) and coefficient of variation (CV) were calculated to reflect within and between-session agreement. Reliability was assessed using intraclass correlation coefficients (ICC1,1). Results Within-session agreement expressed as SEM ranged from 42 to 74 kPa, depending on the test location and device. Between-session agreement, expressed as SEM, ranged from 36 to 76 kPa and the CV ranged from 9–16% per body location. Individual assessors differed from the mean group results, ranging from −55 to +32 kPa or from −9.5 to +6.6 percentage points. Reliability was good to excellent (ICC1,1: 0.87 to 0.95). Results were similar for both types of algometers. Conclusions Following 3 h of algometer practice, there were slight differences between assessors, but reproducibility in determining PPTs was overall good.

Objective: Emerging evidence suggests that individual levels of sensory sensitivity may impact treatment outcomes for people recovering from burn injuries. For example, individuals with higher levels of sensory sensitivity were less adherent with compression garment wear, often used for scar management. The purpose of this study was to characterise sensory patterns for a sample of burn-injured patients as a cohort, using normative data as the reference. As different patterns of sensory processing can have implications clinically, understanding this at the cohort level may provide valuable insight for therapy.Method: This was a secondary analysis of data collected during a cross-sectional study. Adults (N = 117) attending the Professor Stuart Pegg Adult Burns Unit outpatient clinic completed the Adolescent/Adult Sensory Profile and the following quantitative sensory tests: two-point discrimination; mechanical detection threshold; and pressure pain threshold.Results: Compared to matched normative data, burn-injured patients reported higher levels of sensory sensitive and avoiding patterns, and experienced lower detection thresholds for touch and pain.Conclusions: Higher reports of sensory sensitivity and sensory avoiding, and lower thresholds for touch and pain, have been correlated with tactile defensiveness. Tactile defensiveness has been associated with social withdrawal and isolation, all of which could contribute to decreased engagement in therapy. The ways in which these sensory characteristics impact on burn-related treatments, such as compression garment adherence, warrant further investigation. [ABSTRACT FROM AUTHOR]

Background. Conditioned pain modulation (CPM) is measured by comparing pain induced by a test stimulus with pain induced by the same test stimulus, either during (parallel design) or after (sequential design) the conditioning stimulus. Whether design, conditioning stimulus intensity and test stimulus selection affect CPM remains unclear. Methods. CPM effects were evaluated in healthy participants (N D 89) at the neck, forearm and lower leg using the cold pressor test as the conditioning stimulus. In three separate experiments, we compared the impact of (1) design (sequential versus parallel), (2) conditioning stimulus intensity (VAS 40/100 versus VAS 60/100), and (3) test stimulus selection (single versus dual, i.e., mechanical and thermal). Statistical analyses of the main effect of design (adjusted for order) and experiment were conducted using linear mixed models with random intercepts. Results. No significant differences were identified in absolute CPM data. In relative CPM data, a sequential design resulted in a slightly lower CPM effect compared to a parallel design, and only with a mechanical test stimulus at the neck (-6.1%; 95% CI [-10.1 to -2.1]) and lower leg (-5.9%; 95% CI [-11.7 to -0.1]) but not forearm (-4.5%; 95% CI [-9.0 to 0.1]). Conditioning stimulus intensity and test stimulus selection did not influence the CPM effect nor the difference in CPM effects derived from parallel versus sequential designs. Conclusions. Differences in CPM effects between protocols were minimal or absent. A parallel design may lead to a minimally higher relative CPM effect when using a mechanical test stimulus. The conditioning stimulus intensities assessed in this study and performing two test stimuli did not substantially influence the differences between designs nor the magnitude of the CPM effect. [ABSTRACT FROM AUTHOR]

Background Conditioned pain modulation (CPM) is measured by comparing pain induced by a test stimulus with pain induced by the same test stimulus, either during (parallel design) or after (sequential design) the conditioning stimulus. Whether design, conditioning stimulus intensity and test stimulus selection affect CPM remains unclear. Methods CPM effects were evaluated in healthy participants (N = 89) at the neck, forearm and lower leg using the cold pressor test as the conditioning stimulus. In three separate experiments, we compared the impact of (1) design (sequential versus parallel), (2) conditioning stimulus intensity (VAS 40/100 versus VAS 60/100), and (3) test stimulus selection (single versus dual, i.e., mechanical and thermal). Statistical analyses of the main effect of design (adjusted for order) and experiment were conducted using linear mixed models with random intercepts. Results No significant differences were identified in absolute CPM data. In relative CPM data, a sequential design resulted in a slightly lower CPM effect compared to a parallel design, and only with a mechanical test stimulus at the neck (−6.1%; 95% CI [−10.1 to −2.1]) and lower leg (−5.9%; 95% CI [−11.7 to −0.1]) but not forearm (−4.5%; 95% CI [−9.0 to 0.1]). Conditioning stimulus intensity and test stimulus selection did not influence the CPM effect nor the difference in CPM effects derived from parallel versus sequential designs. Conclusions Differences in CPM effects between protocols were minimal or absent. A parallel design may lead to a minimally higher relative CPM effect when using a mechanical test stimulus. The conditioning stimulus intensities assessed in this study and performing two test stimuli did not substantially influence the differences between designs nor the magnitude of the CPM effect.

Background: Changes in quantitative sensory testing (QST) parameters following topical anaesthesia could contribute to better elucidate underlying mechanisms of somatosensory alterations in temporomandibular disorder (TMD) pain patients. This placebo‐controlled crossover investigation compared the somatosensory profile following topical anaesthesia between TMD patients (n = 20) and healthy participants (n = 20). Methods: Cold detection threshold, warm detection threshold, cold pain threshold, heat pain threshold, mechanical detection threshold, mechanical pain threshold, wind‐up ratio and pressure pain threshold were assessed on the skin overlying the masseter at three consecutive days (baseline and immediately after lidocaine 4%/placebo cream). Mixed ANOVA and a coding system that accounts for the diversity of types of peripheral axons associated with the somatosensory parameters were applied for data analysis. Results: The lidocaine application caused no changes in the somatosensory sensitivity in the masseter region in TMD patients (P >.050), but sensitivity to cold, cold pain, touch and pinprick stimuli were reduced after topical anaesthesia in healthy participants (P <.050). Also, the degree of topical anaesthesia was greater in healthy participants (P =.008). The coding system suggested that TMD patients presented only Aδ‐fibre block, whereas a combination of either Aβ‐ and/or C‐fibre block was observed in 35% of healthy participants in addition to Aδ‐fibre block following lidocaine application. Conclusion: Quantitative sensory testing can be successfully applied to identify meaningful differences in the degree of hypoalgesia and hypoesthesia following short‐time topical anaesthesia. [ABSTRACT FROM AUTHOR]

Abstract: Thoracotomy is often responsible for chronic pain, possibly of neuropathic origin. To confirm preclinical studies, the preventive effects of perioperative ketamine were tested in a randomized, double-blind, placebo-controlled clinical trial on persistent neuropathic pain after thoracotomy. Eighty-six patients scheduled for thoracotomy under standardised general anaesthesia were randomised to receive either ketamine (1mgkg−1 at the induction, 1mgkg−1 h−1 during surgery, then 1 mgkg−1 during 24h; n =42) or normal saline (n =44). Postoperative analgesia included a single dose of intrapleural ropivacaine, intravenous paracetamol and nefopam, and patient-controlled intravenous morphine. Vital parameters and analgesia were recorded during the 48 first postoperative hours. Seventy-three patients were followed up. The patient’s chest was examined 1–2 weeks, 6 weeks and 4 months after surgery. At the last two observations, spontaneous pain score over a one-week period (visual analogue scale), neuropathic pain score (NPSI), and intake of analgesics, were assessed. No drug affecting neuropathic pain (except opiates) was given during the follow-up. Two patients in each group were lost to follow-up after the 6 week visit. Ketamine improved immediate postoperative pain, but the groups were similar in terms of neuropathic pain and intake of analgesics, 6 weeks (NPSI score: ketamine: 1.25 [0–4.125]; placebo: 1 [0–4]) and 4 months after surgery. Thus, ketamine given in 24-h infusion failed to prevent chronic neuropathic pain after thoracotomy. Other perioperative preventive long-lasting treatments or techniques could be tested in this context. [Copyright &y& Elsevier]