Validation of a questionnaire for Central nervous system Aspects of joint Pain: the CAP questionnaire.

BACKGROUND AND AIMS: Neuropathic-like pain, fatigue, cognitive difficulty, catastrophising, anxiety, sleep disturbance, depression, and widespread pain associate with a single factor in people with knee pain. We report the Central Aspects of Pain questionnaire (CAP) to characterise this across painful musculoskeletal conditions. METHODS: CAP was derived from the 8 item CAP-Knee questionnaire, and completed by participants with joint pain in the Investigating Musculoskeletal Health and Wellbeing survey. Subgroups had osteoarthritis, back pain or fibromyalgia. Acceptability was evaluated by feedback and data missingness. Correlation coefficients informed widespread pain scoring threshold in relation to the other items, and evaluated associations with pain. Factor analysis assessed CAP structure. Intraclass Correlation Coefficient (ICC) between paper and electronic administration assessed reliability. Friedman test assessed score stability over 4 years in people reporting knee osteoarthritis. RESULTS: Data were from 3579 participants (58% female, median age; 71 years), including subgroups with osteoarthritis (n = 1158), back pain (n = 1292) or fibromyalgia (n = 177). Across the 3 subgroups, ≥10/26 painful sites on the manikin scored widespread pain. Reliability was high (ICC= 0.89 (95% CI: 0.84-0.92)) and CAP scores fit to 1 and 2 factor model, with a total CAP score that was associated with pain severity and quality (r = 0.50-0.72). In people with knee pain, CAP scores were stable over 4 years at the group level, but displayed significant temporal heterogeneity within individual participants. CONCLUSIONS: Central Aspects of Pain is reliably measured by the CAP questionnaire across a range of painful musculoskeletal conditions, and is a changeable state.

A systematic review of quantitative EEG findings in Fibromyalgia, Chronic Fatigue Syndrome and Long COVID.

Fibromyalgia Syndrome (FMS), Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Long COVID (LC) are similar multisymptom clinical syndromes but with difference in dominant symptoms in each individual. There is existing and emerging literature on possible functional alterations of the central nervous system in these conditions. This review aims to synthesise and appraise the literature on resting-state quantitative EEG (qEEG) in FMS, ME/CFS and LC, drawing on previous research on FMS and ME/CFS to help understand neuropathophysiology of the new condition LC. A systematic search of MEDLINE, Embase, CINHAL, PsycINFO and Web of Science databases for articles published between December 1994 and September 2023 was performed. Out of the initial 2510 studies identified, 17 articles were retrieved that met all the predetermined selection criteria, particularly of assessing qEEG changes in one of the three conditions compared to healthy controls. All studies scored moderate to high quality on the Newcastle-Ottawa scale. There was a general trend for decreased low-frequency EEG band activity (delta, theta, and alpha) and increased high-frequency EEG beta activity in FMS, differing to that found in ME/CFS. The limited LC studies included in this review focused mainly on cognitive impairments and showed mixed findings not consistent with patterns observed in FMS and ME/CFS. Our findings suggest different patterns of qEEG brainwave activity in FMS and ME/CFS. Further research is required to explore whether there are phenotypes within LC that have EEG signatures similar to FMS or ME/CFS. This could inform identification of reliable diagnostic markers and possible targets for neuromodulation therapies tailored to each clinical syndrome.

Should Subanesthetic Ketamine be Considered When Managing Opioid Refractory Cancer Pain?

In the cancer pain setting, ketamine has been typically employed as a co-analgesic for opioid refractory and neuropathic pain. One controversial topic is whether subanesthetic ketamine be considered when managing opioid refractory cancer pain. In this "Controversies in Palliative Care" article, three clinicians independently answer this question. Specifically, each clinician provides a synopsis of the key studies that inform their thought processes, share practical advice on their clinical approach, and highlight the opportunities for future research. Three independent clinicians reported a divergence of opinion regarding the usefulness of subanesthetic ketamine for managing opioid refractory cancer pain. All investigators acknowledged the lack of high-quality trials. All agreed on the need for adequately powered trials, the development of standardized methodology, and the exploration of any patient sub-populations that may benefit from ketamine for cancer related pain.

Neuropathic pain in cats: Mechanisms and multimodal management.

PRACTICAL RELEVANCE: Chronic pain is a significant welfare concern in cats, and neuropathic pain, which arises from aberrant processing of sensory signals within the nervous system, is a subcategory of this type of pain. To comprehend this condition and how multimodal pharmacotherapy plays a central role in alleviating discomfort, it is crucial to delve into the anatomy of nociception and pain perception. In addition, there is an intricate interplay between emotional health and chronic pain in cats, and understanding and addressing the emotional factors that contribute to pain perception, and vice versa, is essential for comprehensive care.Clinical approach:Neuropathic pain is suspected if there is abnormal sensation in the area of the distribution of pain, together with a positive response to trial treatment with drugs effective for neuropathic pain. Ideally, this clinical suspicion would be supported by confirmation of a lesion at this neurolocalisation using diagnostic modalities such as MRI and neuroelectrophysiology. Alternatively, there may be a history of known trauma at that site. A variety of therapies, including analgesic, anti-inflammatory and adjuvant drugs, and neuromodulation (eg, TENS or acupuncture), can be employed to address different facets of pain pathways.Aim:This review article, aimed at primary care/ general practitioners, focuses on the identification and management of neuropathic pain in cats. Three case vignettes are included and a structured treatment algorithm is presented to guide veterinarians in tailoring interventions.Evidence base:The review draws on current literature, where available, along with the author's extensive experience and research.

The Association of Central Sensitisation with Depression, Anxiety, and Somatic Symptoms: A Cross-Sectional Study of a Mental Health Outpatient Clinic in Japan.

For patients with chronic pain and persistent physical symptoms, understanding the mechanism of central sensitisation may help in understanding how symptoms persist. This cross-sectional study investigated the association of central sensitisation with depression, anxiety, and somatic symptoms. Four hundred and fifteen adults attending an outpatient psychosomatic clinic were evaluated. Participants completed the Hospital Anxiety and Depression Scale, Somatic Symptom Scale 8, and the Central Sensitisation Inventory. The relationships between these factors were examined using descriptive statistics and multiple logistic regression analyses. The mean age was 42.3 years, and 59% were female. The disorders included adjustment disorders (n = 70), anxiety disorders (n = 63), depressive disorders (n = 103), feeding and eating disorders (n = 30), sleep-wake disorders (n = 37), somatic symptoms and related disorders (n = 84), and others (n = 28). In multiple logistic regression analyses, higher central sensitisation was associated with more severe anxiety, depression, and somatic symptoms after controlling for potential confounders. In the disease-specific analysis, somatic symptoms correlated more positively with central sensitisation than with depression or anxiety. Central sensitisation and depression, anxiety, and somatic symptoms were associated with patients attending an outpatient clinic. These findings highlight the importance of evaluating depression, anxiety, and somatic symptoms when assessing central sensitisation.

Central Sensitisation Syndrome: A Frequent Finding in Women with Pelvic Floor Symptoms Without Evident Urogenital Prolapse.

INTRODUCTION AND HYPOTHESIS: Women with central sensitisation syndrome (CSS) experience poorer subjective post-operative outcomes even after successful pelvic floor reconstruction. This study tests the hypothesis that women with pelvic floor symptoms (PFS) without relevant pelvic organ prolapse (POP), are more likely to have CSS. METHODS: A questionnaire was sent to women who participated in the POP-UP study in 2017. The POP-UP study evaluated POP in 247 women 16 years after laparoscopic or vaginal hysterectomy. POP-Q data and Pelvic Floor Distress Inventory (PFDI-20) results were used and supplemented with CSS-specific questionnaires. A Central Sensitisation Inventory (CSI) score above 40 implicates CSS. Women were divided into groups based on POP beyond the hymen in relation to the PFDI-20 score. Outcomes of women with PFS and without POP (called 'group 1') were compared with the rest of the cohort (groups 2-4; women without PFS and/or with POP). RESULTS: A total of 136 women were included in the analysis. A CSI score above 40 was present in 16 out of 42 women of group 1 (37%) versus 11 out of 93 women of groups 2-4 (12%), p < 0.0001. Passive coping was more prevalent in group 1 (p = 0.039), and more deviations in somatisation, depression, anxiety and distress were found in group 1 (p values of < 0.0001, 0.018, 0.003 and 0.002 respectively). CONCLUSIONS: This study suggests that CSS might be more prevalent in women with PFS without relevant POP. More awareness of CSS and valid individual counselling may overcome unnecessary surgery for POP and help in setting realistic expectations.

Low central sensitisation inventory score is associated with better post-operative outcomes of osteotomy around the knee.

PURPOSE: The purpose of this study was to investigate the potential association between central sensitisation inventory (CSI) scores and post-operative patient-reported outcomes (PROs) in patients underwent osteotomy around the knee (OAK), with a CSI cut-off score specific for knee osteoarthritis. METHODS: CSI scores were collected from 173 patients who underwent OAK, along with their knee injury and osteoarthritis outcome score (KOOS) and pain numeric rating scale (NRS) scores. Patients were divided into high-CSI score group and low-CSI score group with a cut-off score of 17. Multivariate linear regression was performed to test the association between CSI scores and post-operative outcomes. Pre-surgery KOOS and NRS scores and the rate of attainment of minimal clinically important difference (MCID) of KOOS scores was analysed as secondary outcomes. RESULTS: Low-CSI score group had significantly higher post-operative KOOS scores and lower pain NRS scores compared to the high-CSI score group (< p = 0.01) after adjusting for confounding factors. For pre-operative scores, only the KOOS-Symptom score was significantly different between the groups (64.7 ± 20.1 when CSI < 17 vs.55.1 ± 19.7 when CSI ≥ 17; p = 0.008). The low-CSI score group had significantly higher MCID achievement rates of KOOS-Pain, Symptom, and ADL than the high-CSI score group (86% vs. 68%; 74% vs. 55%; 86% vs. 67%, respectively; P < 0.05). CONCLUSIONS: This study established an association between post-operative CSI scores ≥ 17 and poorer outcomes following OAK, highlighting the potential value of the CSI in identifying patients in need of more comprehensive peri-operative pain management. LEVEL OF EVIDENCE: Level III. Retrospective comparative study.

The major pain source of rotator cuff-related shoulder pain: A narrative review on current evidence.

BACKGROUND: Rotator cuff-related shoulder pain (RCRSP) was proposed to have a complex pain mechanism, but the exact aetiology is still unclear. A recent review summarised the updated research to analyse the traditional concept of shoulder impingement which may not be accurate. Current studies have demonstrated that mechanical factors including a reduction in subacromial space, scapular dyskinesia and different acromial shapes are unlikely directly contributing to RCRSP. AIMS: Since the precise RCRSP pain mechanism remains unclear, the aim of this narrative review is to discuss possible sources of pain contributing to RCRSP according to the mechanisms-based pain classifications. RESULTS AND DISCUSSION: Research findings on potential mechanical nociceptive factors of RCRSP are conflicting; investigations of neuropathic and central pain mechanisms of RCRSP are limited and inconclusive. Overall, available evidence has indicated moderate to strong correlations between RCRSP and chemical nociceptive sources of pain. CONCLUSION: Results from current research may provide new directions for future studies on the aetiology of RCRSP and its clinical management towards a biochemical view instead of the traditional mechanical hypothesis.

Altered GABAA receptor function in women with endometriosis: a possible pain-related mechanism.

INTRODUCTION: The mechanism underlying endometriosis-related pain remains poorly understood. Previous studies have indicated that γ-aminobutyric acid (GABA) type A (GABAA ) receptors and GABAergic substances (eg endogenous neurosteroids) play important mechanistic roles in various pain conditions. Our primary objective was to compare GABAA receptor function between women with endometriosis and healthy controls by performing a challenge test with diazepam, a GABAA receptor agonist, using the saccadic eye velocity as the main outcome. The secondary objective was to investigate the relation between GABAA receptor function and serum levels of allopregnanolone, an endogenous positive modulator of the GABAA receptor, in the participating women. MATERIAL AND METHODS: 15 women with pelvic pain and laparoscopically confirmed endometriosis and 10 healthy, symptom-free, control women, aged 18-40 years, underwent the diazepam challenge test during the follicular phase of the menstrual cycle. Basal serum allopregnanolone levels were measured prior to diazepam injection. RESULTS: Compared with healthy controls, women with pelvic pain and confirmed endometriosis had a significantly smaller change in saccadic eye velocity after GABAA receptor stimulation with diazepam, indicating lower sensitivity to diazepam. The saccadic eye velocity response was not correlated with the serum allopregnanolone levels. CONCLUSIONS: Women with painful endometriosis show altered GABAA receptor function, depicted as a muted response to an exogenous GABAA receptor agonist.

Diagnosing nociplastic pain in cancer survivors: a major step forward.

Nociplastic pain syndromes include particular fibromyalgia, irritable bowel syndrome, headache, complex regional pain syndrome, and idiopathic orofacial pain. Several mechanisms have been proposed to account for nociplastic pain including central sensitisation, alterations of pain modulatory controls, epigenetic changes, and peripheral mechanisms. Importantly, nociplastic pain might also be present in patients with cancer pain, particularly those with pain related to complications of cancer treatment. Increased awareness of nociplastic pain associated with cancer should have important implications for monitoring and managing such patients.

Towards precision pain medicine for pain after cancer: the Cancer Pain Phenotyping Network multidisciplinary international guidelines for pain phenotyping using nociplastic pain criteria.

Pain after cancer remains underestimated and undertreated. Precision medicine is a recent concept that refers to the ability to classify patients into subgroups that differ in their susceptibility to, biology, or prognosis of a particular disease, or in their response to a specific treatment, and thus to tailor treatment to the individual patient characteristics. Applying this to pain after cancer, the ability to classify post-cancer pain into the three major pain phenotypes (i.e. nociceptive, neuropathic, and nociplastic pain) and tailor pain treatment accordingly, is an emerging issue. This is especially relevant because available evidence suggests that nociplastic pain is present in an important subgroup of those patients experiencing post-cancer pain. The 2021 International Association for the Study of Pain (IASP) clinical criteria and grading system for nociplastic pain account for the need to identify and correctly classify patients according to the pain phenotype early in their treatment. These criteria are an important step towards precision pain medicine with great potential for the field of clinical oncology. Within this framework, the Cancer Pain Phenotyping (CANPPHE) Network, an international and interdisciplinary group of oncology clinicians and researchers from seven countries, applied the 2021 IASP clinical criteria for nociplastic pain to the growing population of those experiencing post-cancer pain. A manual is provided to allow clinicians to differentiate between predominant nociceptive, neuropathic, or nociplastic pain after cancer. A seven-step diagnostic approach is presented and illustrated using cases to enhance understanding and encourage effective implementation of this approach in clinical practice.

Novice assessors demonstrate good intra-rater agreement and reliability when determining pressure pain thresholds; a cross-sectional study.

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.

Central and peripheral mechanisms of pain in fibromyalgia: scoping review protocol.

Fibromyalgia is characterised by widespread musculoskeletal pain, which may present with fatigue, depression, anxiety, sleep and cognitive disturbances. It is the second most prevalent rheumatic disease. An accurate diagnosis is challenging, since its symptoms may resemble diverse conditions such as carpal tunnel syndrome, Raynaud syndrome, Sjögren syndrome, amongst others. Neuropathic pain and autonomic dysfunction in fibromyalgia suggest the involvement of the nervous system. Ion channels, neurotransmitters and neuromodulators may play a role. Small fibre neuropathy (SFN) may also cause chronic widespread pain. SFN may occur in 50% of fibromyalgia patients, but its role in the disease is unknown. Despite several efforts to synthesise the evidence on the mechanisms for pain in fibromyalgia, there are few studies applying an integrative perspective of neurochemical, immunological, and neuroanatomical characteristics, and their relevance to the disease. This protocol aims to clarify the mechanisms of the central and peripheral nervous system associated with pain in fibromyalgia. We will retrieve published studies from Web of Science, MEDLINE, Scopus, EBSCOhost, Ovid and Google Scholar. All clinical studies or experimental models of fibromyalgia reporting imaging, neurophysiological, anatomical, structural, neurochemical, or immunological characteristics of the central or peripheral nervous systems associated with pain will be included. Exclusion criteria will eliminate studies evaluating pain without a standardised measure, studies written in languages different from Spanish or English that could not be appropriately translated, and studies whose full-text files could not be retrieved after all efforts made. A narrative synthesis will be performed.

Risk factors for persistent pain after breast cancer surgery: a multicentre prospective cohort study.

Identifying factors associated with persistent pain after breast cancer surgery may facilitate risk stratification and individualised management. Single-population studies have limited generalisability as socio-economic and genetic factors contribute to persistent pain development. Therefore, this prospective multicentre cohort study aimed to develop a predictive model from a sample of Asian and American women. We enrolled women undergoing elective breast cancer surgery at KK Women's and Children's Hospital and Duke University Medical Center. Pre-operative patient and clinical characteristics and EQ-5D-3L health status were recorded. Pain catastrophising scale; central sensitisation inventory; coping strategies questionnaire-revised; brief symptom inventory-18; perceived stress scale; mechanical temporal summation; and pressure-pain threshold assessments were performed. Persistent pain was defined as pain score ≥ 3 or pain affecting activities of daily living 4 months after surgery. Univariate associations were generated using generalised estimating equations. Enrolment site was forced into the multivariable model, and risk factors with p < 0.2 in univariate analyses were considered for backwards selection. Of 210 patients, 135 (64.3%) developed persistent pain. The multivariable model attained AUC = 0.807, with five independent associations: age (OR 0.85 95%CI 0.74-0.98 per 5 years); diabetes (OR 4.68, 95%CI 1.03-21.22); pre-operative pain score at sites other than the breast (OR 1.48, 95%CI 1.11-1.96); previous mastitis (OR 4.90, 95%CI 1.31-18.34); and perceived stress scale (OR 1.35, 95%CI 1.01-1.80 per 5 points), after adjusting for: enrolment site; pre-operative pain score at the breast; pre-operative overall pain score at rest; postoperative non-steroidal anti-inflammatory drug use; and pain catastrophising scale. Future research should validate this model and evaluate pre-emptive interventions to reduce persistent pain risk.

Non-inflammatory pain in inflammatory arthritis.

'Non-inflammatory' pain, pain that is not associated with measures of inflammation, is common in patients with inflammatory arthritis including RA. One important cause of non-inflammatory pain is concomitant fibromyalgia. Systematic review has shown that fibromyalgia is common in inflammatory arthritis including RA affecting 1 in 5 patients and is associated with higher disease activity scores due to inflated tender joint count and patient global assessment. Consequently, many patients with RA and concomitant fibromyalgia may fail to reach treatment target and switch to alternate disease modifying drugs frequently. European Alliance of Association for Rheumatology has highlighted that concomitant fibromyalgia is an important consideration in assessing difficult-to-treat RA. The incidence and prevalence of fibromyalgia are higher in RA than the general population, raising the possibility that fibromyalgia may be 'secondary' to RA rather than a concomitant disease. The precise mechanisms whereby patients with RA develop fibromyalgia are unknown. In this review, we discussed fibromyalgia in RA, its clinical impact and epidemiology as well as data suggesting fibromyalgia might be 'secondary'. Lastly, we reviewed potential pathogenic mechanisms which included inflammatory cytokines sensitizing nociceptive neurones, temporal summation, also known as windup, from chronic pain and impaired coping from poor quality sleep and mental well-being. Deciphering the exact mechanisms may lead to treatment strategies that prevent development of secondary fibromyalgia and will address a common factor associated with difficult-to-treat RA.

Central Sensitisation Inventory-Thai version: translation, cross-cultural adaptation, and psychometric evaluation in chronic non-specific neck pain.

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 ω-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.Implications for rehabilitationCentral Sensitisation Inventory-Thai version (CSI-Thai) is successfully adapted and demonstrated satisfactory reliability and construct validity.The CSI-Thai can be applicable to assess central sensitisation-related signs and symptoms in Thai-speaking patients with chronic non-specific neck pain (CNSNP) both clinical and research purposes.The CSI-Thai correlated to pain, disability and quality of life among patients with CNSNP.

Bladder pain syndrome/interstitial cystitis response to nerve blocks and trigger point injections.

Objectives: Bladder pain syndrome (BPS)/interstitial cystitis (IC) is a debilitating condition characterised by bladder/pelvic pain and pressure as well as persistent or recurrent urinary symptoms in the absence of an identifiable cause. It is hypothesised that in addition to organ specific visceral hypersensitivity, contributions of the hypertonic pelvic floor, peripheral sensitisation, and central sensitisation exacerbate this condition. The aim of this paper is to investigate outcomes of treating underlying neuromuscular dysfunction and neuro-plastic mechanisms in BPS/IC patients. Methods: A retrospective chart review of 84 patients referred to an outpatient pelvic rehabilitation centre with a diagnosis of BPS/IC given to them by a urologist. All 84 patients failed to progress after completing 6 weeks of pelvic floor physical therapy and underwent an institutional review board approved protocol (IRB# 17-0761) consisting of external ultrasound-guided trigger point injections to the pelvic floor musculature, peripheral nerve blocks of the pudendal and posterior femoral cutaneous nerves and continued pelvic floor physical therapy once weekly for 6 weeks. Pelvic pain intensity and functionality were measured pretreatment and 3 months posttreatment using Visual Analogue Scale (VAS) and Functional Pelvic Pain Scale (FPPS). Results: Pretreatment, mean VAS was 6.23 ± 2.68 (95% CI 5.65 to 6.80). Posttreatment mean VAS was 3.90 ± 2.63 (95% CI 3.07-4.74). Mean FPPS before treatment was 11.98 ± 6.28 (95% CI 10.63 to 13.32). Posttreatment mean FPPS was 7.68 ± 5.73 (95% CI 6.45-8.90). Analysis of subcategories within FPPS indicated highest statistically significant improvement in the categories of bladder, intercourse and working. Conclusions: Analysis suggests the treatment was effective at ameliorating bladder pain and function including urinary urgency, frequency, and burning in BPS/IC patients.

Algometry for the assessment of central sensitisation to pain in fibromyalgia patients: a systematic review.

INTRODUCTION: 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. OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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. KEY MESSAGESAlgometry 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.

Autism and chronic ill health: an observational study of symptoms and diagnoses of central sensitivity syndromes in autistic adults.

BACKGROUND: Autistic adults, particularly women, are more likely to experience chronic ill health than the general population. Central sensitivity syndromes (CSS) are a group of related conditions that are thought to include an underlying sensitisation of the central nervous system; heightened sensory sensitivity is a common feature. Anecdotal evidence suggests autistic adults may be more prone to developing a CSS. This study aimed to investigate the occurrence of CSS diagnoses and symptoms in autistic adults, and to explore whether CSS symptoms were related to autistic traits, mental health, sensory sensitivity, or gender. METHODS: The full sample of participants included 973 autistic adults (410 men, 563 women, mean age = 44.6) registered at the Netherlands Autism Register, who completed questionnaires assessing autistic traits, sensory sensitivity, CSS, physical and mental health symptoms. The reliability and validity of the Central Sensitization Inventory (CSI) in an autistic sample was established using exploratory and confirmatory factor analyses. Chi2 analyses, independent t-tests, hierarchical regression and path analysis were used to analyse relationships between CSS symptoms, autistic traits, measures of mental health and wellbeing, sensory sensitivity, age and gender. RESULTS: 21% of participants reported one or more CSS diagnosis, and 60% scored at or above the clinical cut-off for a CSS. Autistic women were more likely to report a CSS diagnosis and experienced more CSS symptoms than men. Sensory sensitivity, anxiety, age and gender were significant predictors of CSS symptoms, with sensory sensitivity and anxiety fully mediating the relationship between autistic traits and CSS symptoms. LIMITATIONS: Although this study included a large sample of autistic adults, we did not have a control group or a CSS only group. We also could not include a non-binary group due to lack of statistical power. CONCLUSIONS: CSS diagnoses and symptoms appear to be very common in the autistic population. Increased awareness of an association between autism and central sensitisation should inform clinicians and guide diagnostic practice, particularly for women where CSS are common and autism under recognised.

Evaluation of intraoperative ketamine on the prevention of severe rebound pain upon cessation of peripheral nerve block: a prospective randomised, double-blind, placebo-controlled study.

BACKGROUND: Pain after resolution of peripheral nerve block, known as 'rebound pain' (RP), is a major problem in outpatient surgery. The primary objective was to evaluate the benefit of intraoperative ketamine at an anti-hyperalgesic dose on the incidence of rebound pain after upper limb surgery under axillary plexus block in ambulatory patients. The secondary objective was to better understand the rebound pain phenomenon (individual risk factors). METHODS: In this prospective, double-blind study, patients were randomised to receive either a single dose of i.v. ketamine (0.3 mg kg-1) or a placebo. Preoperative mechanical temporal summation and central sensitization inventory were applied to question underlying central sensitisation. Pain catastrophising and Douleur Neuropathique 4 questionnaires were used. Rebound pain was defined as pain intensity score >7 (numeric rating scale, 0-10) after block resolution. Postoperative pain was recorded at Days 1, 4, and 30 after discharge. RESULTS: A total of 109 subjects completed the study, and 40.4% presented with rebound pain. Ketamine administration did not reduce rebound pain incidence or intensity. Temporal summation and central sensitisation inventory scores did not differ between subjects with and without rebound pain. The predictive risk factors were bone surgery (odds ratio [OR]=5.2; confidence interval [CI], 1.9-14.6), severe preoperative pain (OR=4.2; CI, 1.5-11.7), and high pain catastrophising (OR=4.8; CI, 1.0-22.3). At Day 30, the average daily pain was higher in the rebound pain group involving neuropathic characteristics. CONCLUSION: Ketamine at an anti-hyperalgesic dose showed no benefit on rebound pain development. Although central sensitisation might not be involved, preoperative pain intensity, and catastrophising stand as risk factors. Because rebound pain remains frequent despite adequate procedure-specific postoperative analgesia, future studies should focus on patient-specific pain management.