The development and psychometric validation of the central sensitization inventory

The Association Between the Central Sensitisation Inventory and Temporomandibular Disorders Is Confounded by Migraine, Depression, Widespread Pain and Parafunction. A Cross-Sectional Telehealth Study

BACKGROUND

Temporomandibular disorders (TMDs) are conditions that involve the temporomandibular joints, masticatory muscles, and associated tissues, causing orofacial pain. Central sensitisation (CS) is a relevant part of the TMD pathophysiology. Migraine, psychological aspects, parafunctional oral habits and widespread pain are commonly associated with both TMD and CS and could confound the association between them.

OBJECTIVES

To investigate the association between painful TMD and the Central Sensitisation Inventory (CSI) score, and to assess the presence of confounders in this association.

METHODS

Cross-sectional study that assessed women with and without orofacial pain complaints using telehealth. The TMD Pain Screener and an online physical examination determined the presence of painful TMD. The following questionnaires were applied: CSI, Headache Screening Questionnaire, Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, Oral Behavior Checklist, Jaw Functional Limitation Scale and the Nordic musculoskeletal questionnaire. A single regression investigated the association between the CSI score and TMD, and a multiple regression investigated the effect of the other outcomes as possible confounders. Confounding was considered present when the association between TMD and the CSI score changed more than 10% after adding a possible confounder to the regression model.

RESULTS

Forty-two women with painful TMD and 53 without TMD were included. There was a significant association between the CSI score and the presence of painful TMD (R2 = 0.639; p < 0.001). This association changed when the following outcomes were added to the model: presence of migraine, symptoms of depression, widespread pain and parafunctional oral habits.

CONCLUSION

The positive association between TMD and the CSI score was confounded by migraine, symptoms of depression, widespread pain and parafunctional oral habits.

The effect of eye movement desensitization and reprocessing on fibromyalgia: A multiple-baseline experimental case study across ten participants

Fibromyalgia (FM) is a chronic pain disorder characterized by widespread musculoskeletal pain, fatigue, and stiffness in muscles and joints. Traumatic life experiences and post-traumatic stress symptoms play a role in its development and persistence. Although previous research suggests that pain and FM symptoms decrease after eye movement desensitization and reprocessing (EMDR) therapy, its effectiveness has not been investigated in a controlled manner. The present study investigated the effectiveness of a six-session, 90-minute EMDR therapy using a multiple baseline single-case experimental design (SCED) across ten adult females with FM. The SCED involved a baseline, intervention, one- and three-month follow-up phase. The primary outcome was pain. Secondary outcomes included post-traumatic stress symptoms, other FM symptoms (fatigue, stiffness in muscles and joints), and the impact of FM on daily activities and sleep. Data were statistically analyzed by primarily testing means across phases on an individual and group level. Post-traumatic stress symptoms improved significantly in seven participants. Pain severity decreased significantly in six participants, with three of them maintaining significant improvement three months later. One participant showed clinically relevant change one month later. Furthermore, improvements were observed in secondary outcome measures. The findings support the efficacy of EMDR in reducing FM symptoms.

Sleep and circadian rhythm disturbances as risk and progression factors for multiple chronic overlapping pain conditions: a protocol for a longitudinal study

Introduction

Chronic overlapping pain conditions (COPCs), such as chronic low back pain (cLBP) and fibromyalgia, frequently cooccur and incur substantial healthcare costs. However, to date, much focus has been placed on individual anatomically based chronic pain conditions, whereas little is known about the mechanisms underlying progression to multiple (more than 1) COPCs. This study aims to address the gap by investigating the role of common and modifiable risk factors, specifically sleep and circadian rhythm disturbances, in the development of multiple COPCs.

Methods

The study will enroll 300 participants with cLBP, including 200 with cLBP only and 100 with cLBP plus other COPCs (ie, fibromyalgia, temporomandibular disorders, irritable bowel syndrome, and chronic headaches) and follow them up for 12 months. Sleep and circadian rhythms will be assessed using wireless sleep electroencephalography, 24-hour evaluation of the rhythm of urinary 6-sulfatoxymelatonin, actigraphy, and sleep diaries. Pain amplification using quantitative sensory testing, psychological distress using validated self-report measures, and the number of pain sites using a pain body map will also be assessed.

Perspectives

This research aims to (1) comprehensively characterize sleep/circadian disturbances in individuals with single and multiple COPCs using multimodal in-home assessments; (2) examine the associations between sleep/circadian disturbances, changes in pain amplification, and psychological distress; and (3) investigate the relationship among these factors and the progression in the number of pain sites, a proxy for multiple COPCs. The findings will provide insights into the mechanisms leading to multiple COPCs, potentially informing treatment and prevention strategies for these complex conditions.

Effect of locomotive syndrome on knee pain in severe knee osteoarthritis

BACKGROUND

Locomotive syndrome (LS) presents symptoms related to decreased mobility due to musculoskeletal disorders. Knee osteoarthritis (KOA) is a significant public health concern linked to age-related musculoskeletal issues and is among the conditions contributing to LS. Age-related lower extremity muscle weakness exacerbates knee pain in KOA, but the impact of LS on knee pain is not clear, prompting the present investigation.

METHODS

We conducted a cross-sectional study of 76 participants (152 knee joints) with bilateral severe KOA scheduled for total knee arthroplasty. The study investigated the association between the Knee Injury and Osteoarthritis Outcome Score (KOOS) pain subscale and LS using a multiple linear regression model, which included covariates and scaled estimated regression coefficients.

RESULTS

LS had a negative impact on KOOS pain (β: 0.35, 95 % confidence interval [CI]: 24.08; -6.05) (p < 0.05) and high self-efficacy had a positive impact (β: 0.25, 95%CI: 1.27; 16.34) (p < 0.05). Age, gender, BMI, Kellgren-Lawrence grade, and Central Sensitization did not influence KOOS pain.

CONCLUSIONS

Our findings demonstrate that LS negatively affected knee pain while self-efficacy positively affected it. LS has been attracting attention in relation to mobility, but the fact that it also affected the knee pain in severe KOA is an important clinical finding. Further research is required to focus on the relationship between the prevention and improvement of LS, and knee pain in severe KOA.

Differential target multiplexed spinal cord stimulation in patients with Persistent Spinal Pain Syndrome Type II: a study protocol for a 12-month multicentre cohort study (DETECT)

INTRODUCTION

Differential target multiplexed spinal cord stimulation (DTM SCS) is a new stimulation paradigm for chronic pain management with the aim of modulating glial cells and neurons in order to rebalance their interactions. Animal studies revealed positive effects of this type of stimulation; however, studies in humans are still scarce, pointing towards the need for an evaluation of the effectiveness and safety of DTM SCS in clinical settings. Furthermore, the differential target multiplexed (DTM) algorithm consists of a combination of several programmes, which will presumably consume more energy from the spinal cord stimulation (SCS) battery. Therefore, the objective of DETECT is to investigate the feasibility, effectiveness and safety of DTM SCS in patients with Persistent Spinal Pain Syndrome Type II through a longitudinal cohort study.

METHODS AND ANALYSIS

DETECT is a prospective multicentre cohort study (n≥250) with a follow-up until 12 months after receiving DTM SCS. The study initiated in October 2021 and is currently still recruiting patients. Self-reporting outcome variables were evaluated at baseline (before SCS) and at 1, 6 and 12 months of DTM SCS. The primary effectiveness endpoint is overall pain intensity, measured with the visual analogue scale. Secondary effectiveness outcome measures are back pain intensity, leg pain intensity, disability, health-related quality of life, pain medication use, functional disability, clinical holistic responder status, self-management, impression of change, work status, pain catastrophising, symptoms of central sensitisation, anxiety, depression and healthcare utilisation. Time spent in different body postures and SCS stimulation parameters will be read out from the pulse generator. The prevalence of technical issues, recharge frequency, (serious) adverse events and the proportion of successful DTM trials will be collected as well. Longitudinal mixed models will be calculated to evaluate the effectiveness of DTM SCS over time.

ETHICS AND DISSEMINATION

The study protocol was approved by the central Ethics Committee of the Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel (B.U.N.1432021000563) and the Ethics Committees of each participating centre. Research findings will be disseminated to key stakeholders through peer-reviewed publications in scientific journals and presentations to clinical audiences.

TRIAL REGISTRATION NUMBER

NCT05068011.

Do measures of central sensitization relate to movement-evoked pain in people with chronic low back pain? A longitudinal prospective study

BACKGROUND

One of the most frequent complaints among people with musculoskeletal pain is pain during physical activity, commonly referred to as movement-evoked pain. It is suggested to be associated with quantitative sensory testing measures of central pain process in individuals with musculoskeletal pain.

OBJECTIVE

To investigate the predictive association between movement-evoked pain scores and measures of central sensitization in patients with chronic nonspecific low back pain. The secondary aim was to determine whether changes in movement-evoked pain scores are associated with changes in measures of central sensitization.

METHODS

In this longitudinal prospective study, 50 participants with chronic low back pain were included. Pain pressure thresholds, temporal summation of pain, descending pain modulation, and the central sensitization index were assessed as measures of central sensitization. Movement-evoked pain was evaluated using the Back Performance Scale and a 5-minute walk test.

RESULTS

Measures of central sensitization, specifically pressure pain thresholds and temporal summation, demonstrated predictive associations with movement-evoked pain measures. In response to treatment, improvements in movement-evoked pain were associated with improvements in measures of central sensitization (i.e., pressure pain thresholds and temporal summation) and improved pressure pain thresholds in the plantar toe significantly predict movement-evoked pain measures experienced during the 5-minute walk test.

CONCLUSIONS

These results imply that movement-evoked pain is related to processes related to central modulation of pain in patients with nonspecific chronic low back pain.

Sensitization-associated and neuropathic-associated symptoms in patients with unilateral lateral elbow tendinopathy: an exploratory study

OBJECTIVES

We evaluate the presence of sensitization-associated symptoms and neuropathic pain features and identify if there is an association between these symptoms and pressure pain sensitivity, pain, and related-disability in lateral elbow tendinopathy.

METHODS

Thirty-seven (43% women, age: 45.5 ± 9.5 years) patients with lateral elbow tendinopathy completed: demographic (i.e. age, height, and weight); clinical (i.e. pain history, pain intensity, and Disabilities of the Arm, Shoulder and Hand); and psychophysical (i.e. pressure pain thresholds at the elbow, cervical spine, hand, and leg) outcomes, and the Central Sensitization Inventory and Self-administered Leeds Assessment of Neuropathic Symptoms and Signs questionnaires. Step-wise multiple linear regression models were performed to identify predictors of sensitization- or neuropathic-associated symptoms.

RESULTS

Six (16%) patients exhibited sensitization-associated symptoms (mean: 46.5, SD: 6.1), whereas 13 (35%) patients showed neuropathic-associated symptoms (mean: 13.5; SD: 1.4). Sensitization-associated symptoms were positively associated with neuropathic-associated symptoms (r = 0.538, P = .001) and negatively associated with pressure pain thresholds at the leg (r = -0.378, P = .021). Neuropathic-associated symptoms were positively associated with related-disability (r = 0.479, P = .003) and negatively associated with pressure pain threshold at the elbow (r = -0.394, P = .017). Stepwise regression analyses revealed that neuropathic-like symptoms explained 26.8% of the variance of sensitization symptoms (r2: 0.268), whereas pressure pain threshold at the elbow explained an additional 6.6% to neuropathic-like symptoms (r2: 0.334).

CONCLUSION

This explorative study identified sensitization- and neuropathic-associated symptoms in 16% and 35% of the people with lateral elbow tendinopathy. Sensitization- and neuropathic-associated symptoms were associated. Pressure pain sensitivity at the elbow (peripheral sensitization) was associated with neuropathic -associated symptoms.

Does Central Sensitization Influence Outcomes of Lumbar Discectomy Surgery in Patients With Lumbar Disc Herniation? A Multicenter Prospective Study

STUDY DESIGN

Multicenter prospective study.

OBJECTIVE

Patients with central sensitization (CS) are reported to be at high risk of poor outcomes after spinal surgery. However, the influence of CS on surgical outcomes for lumbar disc herniation (LDH) remains unknown. This study aimed to examine the association between preoperative CS and surgical outcomes in LDH patients.

METHODS

A total of 100 consecutive patients with LDH (mean age 51.2) who underwent lumbar surgery were included in this study. The extent of CS was evaluated using the central sensitization inventory (CSI), a screening tool for CS-related symptoms. The patients completed the following CSI and clinical outcome assessments (COAs) preoperatively and 12 months postoperatively: the Japanese Orthopaedic Association (JOA) score for back pain, JOA back pain evaluation questionnaire (JOABPEQ), and Oswestry Disability Index (ODI). The association between preoperative CSI scores, and preoperative and postoperative COAs was analyzed, and the postoperative changes were statistically evaluated.

RESULTS

The preoperative CSI score significantly decreased 12 months postoperatively. Preoperative CSI scores showed a significant correlation with most COAs; however, a significant correlation was only identified in the social function and mental health domains of JOABPEC postoperatively. Higher preoperative CSI showed worse preoperative COAs; however, all COAs significantly improved regardless of CSI severity. There were no significant differences in any COAs among the CSI severity groups 12 months postoperatively.

CONCLUSIONS

The results of this study showed that lumbar surgeries significantly improved the COAs regardless of preoperative severity of CS in patients with LDH.

The Impact of Stressful Life Events on Centralized Pain and Pain Intensity: A Combined Model Examining the Mediating Roles of Anger and Perceived Injustice Among Racially Minoritized Adults With Chronic Pain

Stressful life events are highly associated with chronic pain. Yet, research is needed to identify the psychological mechanisms that link life adversity and pain, especially studies that test comprehensive models, recruit racially diverse samples, and measure varied pain-related symptoms. This study examined the relationship between stressful life events and pain in a racially diverse sample and tested the potential mediating roles of both anger and perceived injustice. Both centralized pain symptoms and pain intensity were the outcomes. Analyses consisted of 2 cross-sectional, mediation models among 673 adults with self-reported chronic pain who were racially diverse (Black: n = 258, Latine: n = 254, Asian American: n = 161). The results indicated a positive relationship between stressful life events and centralized pain symptoms (b = 2.53, P < .001) and pain intensity (b = .20, P < .001). In parallel mediation analyses, anger (b = .91, 95% CI = .67, 1.17) and perceived injustice (b = .86, 95% CI = .64, 1.11) acted as partial mediators on centralized pain symptoms. Also, anger (b = .05, 95% CI = .03, .08) and perceived injustice (b = .11, 95% CI = .08, .14) acted as full mediators on pain intensity. The combined psychosocial variables accounted for 51% of centralized pain symptoms and 26% of pain intensity. The findings suggest that psychosocial factors are significantly associated with pain outcomes. Future research is needed to investigate exposure to adversity in life, anger, and perceived injustice together as psychosocial mechanisms of pain symptoms. PERSPECTIVE: Among racially minoritized adults with chronic pain, this article presents empirical evidence that stressful life events, anger, and perceived injustice are associated with centralized pain symptoms and pain intensity. This could guide psychological intervention to focus on anger and perceived injustice, especially when addressing centralized pain.

Value of the central sensitisation inventory in patients with axial spondyloarthritis

BACKGROUND

In many patients with axial spondyloarthritis (axSpA), pain persists despite anti-inflammatory medication. Quantitative sensory testing (QST) indirectly assesses altered somatosensory function, though its clinical practicality is limited. The Central Sensitisation Inventory (CSI) could be an alternative in the initial assessment of central sensitisation (CS). This study aimed to investigate the value of the CSI in evaluating CS in patients with axSpA by (1) assessing somatosensory function related to CS with QST and (2) exploring associations between CSI, QST, patient and disease characteristics and pain-related psychosocial factors.

METHODS

Consecutive outpatients from the Groningen Leeuwarden AxSpA cohort underwent QST, including pressure pain threshold (PPT), temporal summation (TS) and conditioned pain modulation (CPM). Participants completed questionnaires assessing CS (CSI), illness perception (Revised Illness Perception Questionnaire, IPQ-R), pain-related worrying (Pain Catastrophising Scale, PCS), fatigue (Modified Fatigue Impact Scale, MFIS), anxiety/depression (Hospital Anxiety and Depression Scale, HADS) and coping. QST measurements were stratified for CSI≥40.

RESULTS

201 patients with axSpA were included; 63% male, 64% radiographic axSpA, median symptom duration 12 years (IQR 5-24), mean Axial Spondyloarthritis Disease Activity Score 2.1±1.0. Patients with CSI≥40 had significantly lower PPTs and higher TS than CSI<40 (p<0.004). No significant differences in CPM were observed. In multivariable linear regression, sex, PCS, IPQ-R Identity, MFIS and HADS anxiety were independently associated with CSI (78% explained variance).

CONCLUSION

In this large cross-sectional study in patients with axSpA, the CSI appears as a useful initial CS assessment questionnaire. When CSI scores indicate CS, considering pain-related psychosocial factors is important. These results emphasise the need for a biopsychosocial approach to manage chronic pain in patients with axSpA.

An exploratory data-driven approach to classify subgroups of patients with temporomandibular disorders based on pain mechanisms

Temporomandibular disorders (TMDs) are a common musculoskeletal condition, presenting treatment challenges due to their non-specific nature. Categorizing patients with TMDs into clusters based on neurobiological pain mechanisms could provide a promising approach to facilitate targeted treatments. This observational study (1) used a network analysis (NA) to explore the complexity of TMDs by investigating relationships among biopsychosocial variables, and (2) validated potential TMD subgroups based on mechanism-specific pain categories. One hundred and two patients with TMD were included. Biopsychosocial variables covered: general health, psychosocial features, TMD pain, and TMD characteristics. A NA evaluated the associations between variables and determined the role of each feature within the network. Hierarchical clustering was used to identify TMD subgroups. The NA revealed significant correlations primarily within the same feature domains, indicating a strong interplay between symptoms and psychological factors. Cluster analysis identified two subgroups driven by nociceptive and nociplastic pain mechanisms; the nociplastic group exhibited higher levels of anxiety, depression, pain catastrophization, central sensitization, pain duration, and more pain locations, along with poorer sleep quality, quality of life, and health status. In contrast, the nociceptive group exhibited restricted maximal mouth opening (MMO), heightened pain during TMJ palpation and mouth opening, and a greater positive response to manual therapy. Across all features, psychological factors, pain locations, and MMO primarily contributed to the separation of subgroups. By adopting a data-driven approach, these results support the significant role of considering the neurobiological basis of pain to improve patient classification. This knowledge may facilitate clinical reasoning and personalized treatments. PERSPECTIVE: This study used a network analysis to explore the complex biopsychosocial interactions present in people with TMDs, identifying important variables such as the Central Sensitization Inventory and pain-free maximal mouth opening. The findings distinguish potential nociceptive and nociplastic pain subgroups, offering important insights for targeted therapeutic strategies.

From breast cancer diagnosis to survivorship: Analyzing perioperative biopsychosocial phenotypes and their relationship to pain on long term

Persistent breast cancer treatment-related pain affects up to 40% of patients, decreasing their quality of life (QoL). While current research typically utilizes correlation and regression analysis to identify biopsychosocial phenotypes contributing to this pain, this study employs cluster analysis to identify qualitatively different phenotypes based on somatosensory and psychosocial characteristics both before and one week post-breast cancer surgery. Further, it investigates how these phenotypes are related to pain intensity one year post-surgery and examines the evolution of phenotype membership from pre- to post-surgery. Somatosensory and psychosocial functioning was evaluated pre- and post-surgery in 184 women undergoing unilateral breast cancer surgery. Eight different quantitative sensory testing (QST) methods including mechanical detection and pain thresholds, pressure pain thresholds, thermal detection and pain thresholds, and conditioned pain modulation were performed at the surgical area (trunk, arm, major pectoral muscle) and a distant location (quadriceps muscle). Psychosocial functioning was assessed using the Central Sensitization Inventory, Pain Catastrophizing Scale, Depression Anxiety Stress Scale-21, and the McGill Quality of Life Questionnaire. Pain intensity was evaluated one year post-breast cancer surgery using the Visual Analogue Scale. Latent class analysis identified five distinct phenotypes before and post-surgery, characterized by differences in mechanical and pain thresholds alongside psychosocial factors. Moreover, higher psychosocial distress and lower QoL correlated with elevated pain intensity one year post-surgery. These findings underscore the importance of addressing breast cancer patients' mental health perioperatively. Therefore, future research should explore whether psychological interventions perioperatively can reduce long-term pain intensity. PERSPECTIVE: This secondary analysis, utilizing cluster analysis, reveals five distinct phenotype based on somatosensory and psychosocial characteristics both before and post-breast cancer surgery. Higher psychosocial distress and lower quality of life correlated with elevated pain intensity one year post-surgery, emphasizing the need to address patients' mental health perioperatively. TRIAL REGISTRATION: clinicaltrials.gov (NCT03351075).

Alshehri Y. Cross-cultural adaptation and psychometric properties of the Arabic version of the Central Sensitization Inventory in people with chronic musculoskeletal pain

Background

The Central Sensitization Inventory (CSI) is a patient-reported screening instrument that can be used to identify and assess central sensitization (CS)/Central Sensitization Syndrome (CSS)-related symptoms.

Objective

The aim was to translate the CSI into Arabic (CSI-Ar) and to subsequently validate its psychometric properties.

Design

Cross-sectional.

Methods

The CSI was translated and cross-culturally adapted into Arabic, and validated following international standardized guidelines. This study included patients with chronic musculoskeletal pain (n = 264) and healthy control participants (n = 56). Patients completed the CSI-Ar, Pain Catastrophizing Scale (PCS), Depression, Anxiety, and Stress scale (DASS-21), Tampa Scale of Kinesiophobia (TSK), and 5-level EuroQol-5D (EQ-5D). Patients completed the CSI-Ar twice to assess test-retest reliability. To evaluate discriminative validity, healthy controls participants completed the CSI-Ar. Statistical analyses were conducted to test the internal consistency, reliability, and structural, construct and discriminant validity of CSI-Ar.

Results

The CSI-Ar showed acceptable internal consistency (Cronbach's alpha = 0.919) and excellent test-retest reliability (intraclass correlation coefficient = 0.874). The CSI-Ar scale had significant correlations (P < 0.001) with all PCS subscales and total score (Spearman's rho = 0.459-0.563, P < 0.001), all DASS-21 subscales and total score (Spearman's rho = 0.599-0.685, P < 0.001), the TSK (Spearman's rho = 0.395, P < 0.001), and the EQ-5D (Spearman's rho = -0.396, P < 0.001). The Mann-Whitney U-test showed a statistically significant difference between the patient group and the healthy control group (P < 0.001), with the healthy controls displaying a lower average CSI-Ar score (12.27 ± 11.50) when compared to the patient group (27.97 ± 16.08). Factor analysis indicated that the CSI-Ar is a unidimensional tool.

Conclusion

The CSI-Ar is a reliable and valid screening tool that can be used to assess CS/CSS-related symptoms in Arabic-speaking people with chronic musculoskeletal pain.

Establishing an optimal central sensitization inventory cut-off value affecting postoperative outcomes of osteotomy around the knee

BACKGROUND

Central sensitization has a significant effect on pain after osteotomy around the knee (OAK). The central sensitization inventory (CSI) score is considered disease specific, and the appropriate cut-off values for OAK are unclear. The purpose of this study was to establish the optimal CSI cut-off value affecting the postoperative outcomes of OAK based on the postoperative knee injury and osteoarthritis outcome score (KOOS).

METHODS

Patients who underwent OAK for medial compartment knee osteoarthritis were included. The postoperative KOOS symptoms, pain, and activities of daily living (ADL) were categorized into two groups (score ≥80 each for symptoms, pain, and ADL, and score <80 for any of the three) and were used as factors to calculate receiver operating characteristic curves and the area under the curve with the CSI score. Cut-off values were calculated using the Youden index and the threshold value closest to the upper left corner. Subsequently, logistic multivariate analysis was performed using the KOOS and the obtained CSI cut-off values and other variables.

RESULTS

A total of 173 patients were included in this study. The area under the curve of the model was 0.801 (95 % confidence interval, 0.74-0.87), and a CSI score of 12 was determined as the cut-off value. Logistic multivariate analysis based on the cut-off value showed that only the CSI score (odds ratio, 9.79; 95 % CI, 4.47-21.4; P < 0.01) was significant.

CONCLUSIONS

The optimal CSI cut-off value affecting the postoperative outcomes of OAK calculated using the postoperative KOOS was 12, which was supported by multivariate analysis results. Central sensitization assessment with an appropriate cut-off value would allow a more personalized treatment approach and may contribute to a better postoperative outcome.

To Be in Pain: Pain Multidimensional Questionnaire as Reliable Tool to Evaluate Multifaceted Aspects of Pain

Background/Objectives: Pain is a multidimensional experience influenced by sensory, emotional, and cognitive factors. Traditional pain assessments often fail to capture this complexity. This study aimed to develop and validate the Pain Multidimensional Questionnaire (Pa-M-QU), a new self-report tool designed to assess pain catastrophizing, sensitivity, and coping strategies. Methods: Two independent samples of Italian-speaking participants, aged 18 and above, were recruited online. The first sample (n = 392; mean age = 29.36) was used for exploratory factor analysis (EFA), and the second sample (n = 123; mean age = 28.0) for confirmatory factor analysis (CFA). Pearson's correlations and convergent validity analyses were conducted. Results: From an initial pool of 59 items identified through focus group discussions, 35 items were removed based on reliability analysis. The final 24-item Pa-M-QU features a three-factor structure: catastrophizing, pain sensitivity, and coping with pain. Conclusions: The Pa-M-QU offers a rapid, non-invasive assessment that captures the multidimensional nature of pain. It is a starting point to develop tools for both clinical and research settings, aiding in evaluating pain in healthy individuals and predicting acute and chronic pain disorders. Future research should focus on refining the Pa-M-QU for broader clinical applications and exploring its potential to complement or replace traditional pain assessments, thereby advancing pain management and research.

The Factors Impacting on Patient-Reported Outcomes After Bicruciate-Stabilized Total Knee Arthroplasty for Varus Knee Osteoarthritis

Background

The aim of this study was to investigate the factors affecting patient-reported outcomes after bicruciate-stabilized total knee arthroplasty (BCS TKA) in patients.

Methods

We retrospectively examined 122 knees with primary varus knee osteoarthritis that underwent BCS TKA. This study analyzed preoperative, intraoperative, and postoperative predictors of patient satisfaction and persistent postsurgical pain following BCS TKA at 1 year after surgery. We evaluated persistent postsurgical pain using Knee Injury and Osteoarthritis Outcome Score (KOOS) pain subscale and patient satisfaction using a visual analog scale.

Results

The univariate analysis showed a significant negative correlation between the KOOS pain subscale and three factors: the preoperative central sensitization inventory (CSI) score, medial joint laxity at 90° flexion, and acute postsurgical pain. Patient satisfaction was significantly positively correlated with lateral joint laxity at 90° flexion and postoperative extension angle. Acute postsurgical pain had a significant negative correlation with patient satisfaction. The multiple regression analysis revealed preoperative CSI score and medial joint laxity at 90° flexion influenced patients' KOOS pain subscale responses. Only lateral joint laxity at 90° flexion had an impact on patient satisfaction.

Conclusions

The acquisition of adequate soft tissue balance according to the concept of BCS TKA and preoperative central sensitization syndrome affects the clinical outcomes in BCS TKA.

Neuroinflammatory activation in sensory and motor regions of the cortex is related to sensorimotor function in individuals with low back pain maintained by nociplastic mechanisms: A preliminary proof-of-concept study

BACKGROUND

Chronic pain involves communication between neural and immune systems. Recent data suggest localization of glial (brain immune cells) activation to the sensorimotor regions of the brain cortex (S1/M1) in chronic low back pain (LBP). As glia perform diverse functions that impact neural function, activation might contribute to sensorimotor changes, particularly in LBP maintained by increased nervous system sensitivity (i.e., nociplastic pain). This preliminary proof-of-concept study aimed to: (i) compare evidence of neuroinflammatory activation in S1/M1 between individuals with and without LBP (and between nociceptive and nociplastic LBP phenotypes), and (ii) evaluate relationships between neuroinflammatory activation and sensorimotor function.

METHODS

Simultaneous PET-fMRI measured neuroinflammatory activation in functionally defined S1/M1 in pain-free individuals (n = 8) and individuals with chronic LBP (n = 9; nociceptive: n = 4, nociplastic: n = 5). Regions of S1/M1 related to the back were identified using fMRI during motor tasks and thermal stimuli. Sensorimotor measures included single and paired-pulse transcranial magnetic stimulation (TMS) and quantitative sensory testing (QST). Sleep, depression, disability and pain questionnaires were administered.

RESULTS

Neuroinflammatory activation was greater in the lower back cortical representation of S1/M1 of the nociplastic LBP group than both nociceptive LBP and pain-free groups. Neuroinflammatory activation in S1/M1 was positively correlated with sensitivity to hot (r = 0.52) and cold (r = 0.55) pain stimuli, poor sleep, depression, disability and BMI, and negatively correlated with intracortical facilitation (r = -0.41).

CONCLUSION

This preliminary proof-of-concept study suggests that neuroinflammation in back regions of S1/M1 in individuals with nociplastic LBP could plausibly explain some characteristic features of this LBP phenotype.

SIGNIFICANCE STATEMENT

Neuroinflammatory activation localized to sensorimotor areas of the brain in individuals with nociplastic pain might contribute to changes in sensory and motor function and aspects of central sensitization. If cause-effect relationships are established in longitudinal studies, this may direct development of therapies that target neuroinflammatory activation.

Redesigning the Care of Musculoskeletal Conditions With Lifestyle Medicine

Value-based health care has been accelerated by alternative payment models and has catalyzed the redesign of care delivery across the nation. Lifestyle medicine (LM) is one of the fastest growing medical specialties and has emerged as a high-value solution for root cause treatment of chronic disease. This review detailed a large integrated health care delivery system's value transformation efforts in the nonoperative treatment of musculoskeletal (MSK) conditions by placing patient-centric, team-based, lifestyle-focused care at the foundation. With an economic and treatment imperative to reimagine care, recognizing more intervention is not always better, a collaborative approach was designed, which placed functional improvement of the patient at the center. This article described the process of implementing LM into an MSK model of care. The change management process impacted clinical, operational, and benefit plan design to facilitate an integrated care model. A new understanding of patients' co-occurring physical impairments, medical comorbidities, and behavioral health needs was necessary for clinicians to make the shift from a pathoanatomic, transactional model of care to a biopsychosocial, longitudinal model of care. The authors explored the novel intersection of the implementation of a biopsychosocial model of care using LM principles to achieve greater value for the MSK patient population.

Change in Endogenous Pain Modulation Depending on Emotional States in Healthy Subjects: A Randomized Controlled Trial

INTRODUCTION

Chronic pain is a public health issue, leading to substantial healthcare costs and diminished quality of life for sufferers. While the role of anxiety in pain modulation has been extensively studied, the effects of other emotional states on the body's pain control mechanisms remain less understood. This study sought to explore how different emotions (happiness, anger, sadness, and interest) affect conditioned pain modulation (CPM) and the wind-up phenomenon in healthy adults.

METHODS

This randomized controlled, cross-over trial involved 28 healthy participants aged 18-60. Participants watched video clips designed to induce specific emotions: happiness, anger, sadness, and interest. Emotional states were assessed using a 7-point Likert scale. Pain modulation was measured using CPM and the wind-up phenomenon. CPM was assessed with a hot water bath as the conditioning stimulus and pressure pain tolerance as the test stimulus. Wind-up was measured using pinprick needle stimulators and a visual analog scale. Data were analyzed using paired t tests to compare pre- and post-emotion induction values.

RESULTS

Significant changes in emotional self-assessment values were observed for all emotions. Happiness increased CPM (4.6 ± 11.4, p = 0.04277), while sadness - 9.9 ± 23.1, p = 0.03211) and anger - 9.1 ± 23.3, p = 0.04804) decreased it. Interest did not significantly alter CPM (- 5.1 ± 25.8, p = 0.31042). No significant effects were found for the wind-up phenomenon across any emotional states.

CONCLUSION

This study shows that emotional states significantly affect the body's ability to modulate pain. Positive emotions like happiness enhance pain inhibition, while negative emotions such as sadness and anger impair it. These findings suggest that emotional modulation techniques could be integrated into pain management strategies to improve patient outcomes. Further research should explore a broader range of emotions and include objective measures to validate these results.

The profile beyond leg pain: In basis of central sensitization, kinesiophobia, and body awareness in patients with chronic venous disease

Objective: Leg pain has long been underestimated despite being one of the most important symptoms of chronic venous disease (CVD). Studies investigating leg pain and psychosocial profile in CVD are limited. The study aimed to investigate leg pain, central sensitization, kinesiophobia, and body awareness in patients with CVD. Methods: The ninety-eight patients (80 female, 18 male) diagnosed with CVD were included in the study. The severity of leg pain was evaluated with the Visual Analog Scale (VAS). The patients were assessed with the Central Sensitization Inventory (CSI-A and B) for central sensitization-related symptoms and -positivity, the Body Awareness Questionnaire (BAQ) for body awareness, and the Tampa Kinesiophobia Scale (TKS) for kinesiophobia. The cut-off score was admitted as 41 for TKS. Results: The leg pain (mean (SD) = 4.3 ± 2) and body awareness (mean (SD) = 82.4 ± 22) were moderate levels in patients with CVD. Nearly half of the patients (n = 46, 46.9%) had both central sensitization positivity and elevated kinesiophobia (n = 46, 47%). The CSI was correlated with the VAS (r = 0.32, p = .001), TKS (r = 0.40, p < .001), and BAQ (r = 0.20, p = .048). Significant correlations were determined between Body Mass Index and TKS (r = 0.48, p < .001) and BAQ (r = -0.31, p = .002). Also, the patients with a TKS score ≥41-points had higher CSI-A scores (p = .002) than those with a TKS score< 41. Conclusions: Leg pain, central sensitization, and kinesiophobia are commonly seen in patients with CVD, and central sensitization seems to have a negative effect on leg pain, kinesiophobia, and body awareness. The profile beyond pain should be evaluated in detail, and various rehabilitation strategies need to be developed to manage central sensitization, interoception, kinesiophobia, and weight control in patients with CVD.

Efficacy of galcanezumab in migraine central sensitization

Galcanezumab, a monoclonal antibody targeting the calcitonin gene-related peptide pathway (CGRP mAb), acts peripherally due to its large size. However, recent studies have suggested that CGRP mAbs may also have a central mode of action. This study aimed to evaluate the central effects of galcanezumab on migraine central sensitization.This prospective real-world study was conducted at three headache centers in Japan between May 2021 and May 2022. Patients treated with galcanezumab for migraines were included in the study. The primary outcome was the change in the validated Central Sensitization Inventory (CSI) score from baseline to six months of treatment. We also assessed changes in the Allodynia Symptom Checklist (ASC-12) score. Eighty-six patients with migraine (73 female and 13 male) were analyzed. At 6 months, CSI and ASC-12 scores were significantly reduced compared to baseline (CSI: 36.0 vs. 29.3, p < 0.001; and ASC-12: 5.55 vs. 4.26, p < 0.01). Furthermore, these effects were observed as early as three months of treatment. In this study, we demonstrated the real-world efficacy of galcanezumab in improving central sensitization in migraine, with significant effects seen in the early phase of treatment. Trial registration: This study was registered with UMIN-CTR on May 2, 2021 (UMIN000044096).

Is chronic pain caused by central sensitization? A review and critical point of view

Chronic pain causes disability and loss of health worldwide. Yet, a mechanistic explanation for it is still missing. Frequently, neural phenomena, and among them, Central Sensitization (CS), is presented as causing chronic pain. This narrative review explores the evidence substantiating the relationship between CS and chronic pain: four expert researchers were divided in two independent teams that reviewed the available evidence. Three criteria were established for a study to demonstrate a causal relationship: (1) confirm presence of CS, (2) study chronic pain, and (3) test sufficiency or necessity of CS over chronic pain symptoms. No study met those criteria, failing to demonstrate that CS can cause chronic pain. Also, no evidence reporting the occurrence of CS in humans was found. Worryingly, pain assessments are often confounded with CS measures in the literature, omitting that the latter is a neurophysiological and not a perceptual phenomenon. Future research should avoid this misconception to directly interrogate what is the causal contribution of CS to chronic pain to better comprehend this problematic condition.

Nociplastic pain in axial spondyloarthritis and psoriatic arthritis: role of JAK kinases in immunopathology and therapeutic impact of JAK inhibitors

INTRODUCTION

Pain in both peripheral and axial joints is a major symptom in patients with psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA). Emerging evidence demonstrates pain mechanisms, beyond those related to inflammation or joint damage, based on aberrant processing of nociceptive stimuli peripherally as well as centrally. The Janus kinase/signal transducers and activators of transcription (JAK-STAT) signaling pathway has been implicated in the processing of pain beyond its role in mediating inflammation and inhibitors of this pathway approved for the treatment of axSpA and PsA have been shown to alleviate a broad array of pain outcomes in both axial and peripheral joints.

AREAS COVERED

We review recent definitions and standardization of the nomenclature for categorizing chronic pain according to causality, assessment tools to evaluate nociplastic pain, the pathophysiologic role of JAK-STAT signaling in nociplastic pain, evidence for the presence of nociplastic pain in axSpA and PsA, and the impact of JAK inhibitors (JAKi) on pain outcomes in clinical trials (PubMed: 01/01/2019-04/01-2024).

EXPERT OPINION

Nociplastic pain assessment has been confined almost entirely to the use of a limited number of questionnaires in cross-sectional studies of these diseases. Though effective for alleviating pain, it is unclear if JAKi specifically impact nociplastic pain.

The vicious cycle of chronic endometriosis and depression-an immunological and physiological perspective

Endometriosis is a chronic, estrogen-dependent, proinflammatory disease that can cause various dysfunctions. The main clinical manifestations of endometriosis include chronic pelvic pain and impaired fertility. The disease is characterized by a spectrum of dysfunctions spanning hormonal signaling, inflammation, immune dysregulation, angiogenesis, neurogenic inflammation, epigenetic alterations, and tissue remodeling. Dysregulated hormonal signaling, particularly involving estrogen and progesterone, drives abnormal growth and survival of endometrial-like tissue outside the uterus. Chronic inflammation, marked by immune cell infiltration and inflammatory mediator secretion, perpetuates tissue damage and pain. Altered immune function, impaired ectopic tissue clearance, and dysregulated cytokine production contribute to immune dysregulation. Enhanced angiogenesis promotes lesion growth and survival. Epigenetic modifications influence gene expression patterns, e.g., HSD11B1 gene, affecting disease pathogenesis. Endometriosis related changes and infertility lead to depression in diagnosed women. Depression changes lifestyle and induces physiological and immunological changes. A higher rate of depression and anxiety has been reported in women diagnosed with endometriosis, unleashing physiological, clinical and immune imbalances which further accelerate chronic endometriosis or vice versa. Thus, both endometriosis and depression are concomitantly part of a vicious cycle that enhance disease complications. A multidimensional treatment strategy is needed which can cater for both endometrial disease and depression and anxiety disorders.

Impact of Central Sensitization on Clinical and Functional Aspects of Psoriatic Arthritis

Background/Objectives: Psoriatic arthritis (PsA) is an inflammatory rheumatic disease characterized by peripheral arthritis, enthesitis, spondylitis and psoriasis. The objective of this study was to examine the prevalence of central sensitization (CS) and its impact on the clinical and functional aspects of PsA. Methods: Adult patients with PsA according to the Classification of Psoriatic Arthritis (CASPAR) criteria were included in this cross-sectional observational study. The Central Sensitization Inventory (CSI) was used to assess the presence of CS. The study evaluated the impact of CS on individuals by analyzing many factors including demographic information, laboratory findings, clinical features, disease activity, quality of life, severity of sleeplessness, frequency of depression and anxiety. The patients were categorized into distinct groups based on the existence and intensity of CS, and a comparative analysis was conducted on their respective outcomes. Results: A total of 103 PsA patients with a mean age of 43.2 (SD: 6.7) years and including 42 (40.8%) males were included. The mean CSI score was 45.4 (SD: 15.1), and 67 (65.1%) patients had CS. The logistic regression analysis revealed that the variables Psoriasis Area Severity Index (PASI), General Anxiety Disorder-7 (GAD-7), and Insomnia Severity Index (ISI) exhibit considerable predictive power in relation to the outcome variable CS (p < 0.05). PASI was observed as the most important variable in predicting CS (OR 9.70 95% CI: 1.52-62.21). Conclusions: CS has demonstrable efficacy in influencing laboratory, clinical, and functional markers among individuals with PsA. When assessing pain sensitivity in these patients, it is important to take into account the presence of CS.

Pain with orgasm in endometriosis: potential etiologic factors and clinical correlates

BACKGROUND

Pelvic pain worsened by orgasm is a poorly understood symptom in patients with endometriosis.

AIM

To assess the prevalence of pelvic pain worsened by orgasm in patients with endometriosis and explore its association with potential etiologic factors, including pelvic floor myalgia, uterine tenderness and adenomyosis, and central nervous system sensitization.

METHODS

An analysis was done of a prospective data registry based at a tertiary referral center for endometriosis. Eligible participants were patients aged 18 to 50 years who were referred between January 1, 2018, and December 31, 2019, diagnosed with endometriosis, and subsequently underwent surgery at the center. Clinical features were compared between participants reporting worsening pelvic pain with orgasm and those without worsening pain with orgasm, including patient-reported variables, physical examination findings, and anatomic phenotyping at the time of surgery. Pelvic floor myalgia and uterine tenderness were assessed by palpation on pelvic examination, adenomyosis by ultrasound, and central nervous system sensitization via the Central Sensitization Inventory (range, 0-100).

OUTCOMES

Outcomes included pelvic or lower abdominal pain in the last 3 months that worsened with orgasm (yes/no).

RESULTS

Among 358 participants with endometriosis, 14% (49/358) reported pain worsened by orgasm while 86% (309/358) did not. Pain with orgasm was significantly associated with pelvic floor myalgia (55% [27/49] vs 35% [109/309]; Cohen's h = 0.40, P = .01) and higher scores on the Central Sensitization Inventory (mean ± SD, 53.3 ± 17.0 vs 42.7 ± 18.2; Cohen's d = 0.60, P < .001) but not with uterine tenderness or adenomyosis. Other clinical features associated with pain with orgasm were poorer sexual health (higher scores: deep dyspareunia, Cohen's h = 0.60; superficial dyspareunia, Cohen's h = 0.34; and Female Sexual Distress Scale-Revised, Cohen's d = 0.68; all P < .05) and poorer mental health (higher scores: Patient Health Questionnaire-9, 12.9 ± 6.7 vs 9.1 ± 6.3, Cohen's d = 0.59, P < .001; Generalized Anxiety Disorder-7, 9.4 ± 5.6 vs 6.8 ± 5.5, Cohen's d = 0.48, P = .002). Anatomic findings at the time of surgery did not significantly differ between the groups.

CLINICAL IMPLICATIONS

Interventions targeting pelvic floor myalgia and central nervous system sensitization may help alleviate pain worsened by orgasm in patients with endometriosis.

STRENGTHS AND LIMITATIONS

A strength is that pain worsened by orgasm was differentiated from dyspareunia. However, pain with orgasm was assessed by only a binary question (yes/no). Also, the study is limited to a single center, and there were limited data on sexual function.

CONCLUSION

Pelvic pain exacerbated by orgasm in people with endometriosis may be related to concurrent pelvic floor myalgia and central sensitization.

Effects of an arm ergometer for a patient with knee osteoarthritis and central sensitization: A case report

Aerobic exercise may be an effective treatment for knee osteoarthritis and central sensitization, but no interventional studies have examined its effects. In this study, the patient showed improvement in central sensitization, pain, and autonomic nervous system activity after aerobic exercise using an arm ergometer.

Evaluating Sensitization-associated, Neuropathic-like Symptoms and Psychological Factors in Patients With Interstitial Lung Disease

The aims of this study were to phenotype pain in patients with interstitial lung disease (ILD) by investigating the association between sensitization-associated symptoms with quality of life, anxiety/depression, pain catastrophizing, and kinesiophobia levels and identifying those risk factors explaining the variance of quality of life in individuals with ILD and pain. One hundred and thirty-two (38.6% women, mean age: 70, standard deviation: 10.5 years) patients with ILD completed clinical (age, sex, height, weight), psychological (Hospital Anxiety and Depression Scale [HADS] and the Pittsburgh Sleep Quality Index), and health-related quality of life (EQ-5D-5L) variables, as well as the Central Sensitization Inventory (CSI), the Self-Report Leeds Assessment of Neuropathic Symptoms (S-LANSS), Pain Catastrophizing Scale, and Tampa Scale for Kinesiophobia (TSK-11) questionnaires. The prevalence of sensitization-associated symptomatology (CSI), neuropathic-like features (S-LANSS), anxiety symptoms, depressive symptoms, or poor sleep was 20.5%, 23.5%, 23.6%, 22.9%, or 51.6%. Significant associations between CSI, S-LANSS, HADS-A, HADS-D, Pain Catastrophizing Scale, TSK-11, and EQ-5D-5L (.220 < r < .716) were found. The regression analysis revealed that CSI, TSK-11, and HADS-D explained 44.8% of the variance of EQ-5D-5L (r2 adjusted: .448). This study found the presence of sensitization-associated and neuropathic-like symptoms as well as other central nervous system-derived symptoms, such as anxiety, depression, poor sleep, pain catastrophizing, and kinesiophobia in 25% of ILD patients with pain. Sensitization-associated symptoms, depression, and kinesiophobia were associated with a worse quality of life. These findings would support that individuals with ILD can exhibit different pain phenotypes, including nociplastic-like pain phenotype based on self-reported measurements. PERSPECTIVE: Pain in patients with ILD can fulfill features of different phenotypes, including nociplastic pain, when sensory, emotional, and cognitive mechanisms are involved at the same time.

Reliability of Pressure Pain Threshold (PPT) and Conditioned Pain Modulation (CPM) in Participants with and without Chronic Shoulder Pain

The objectives of this study were to estimate the intra-rater and inter-rater reliability of the Pressure Pain Threshold (PPT) and Conditioned Pain Modulation (CPM) in healthy participants and patients with chronic shoulder pain. Additionally, the Standard Error of Measurement (SEM) and Smallest Detectable Change (SDC) were calculated. Thirty-one healthy volunteers and twenty patients with chronic shoulder pain were assessed using the PPT and CPM by two raters, with a 24 h interval between sessions. Excellent intra-rater reliability was demonstrated for PPT, with similar SEM and SDC when assessed by the same rater. The inter-rater reliability for PPTs in patients was moderate to good (ICC = 0.59-0.89) with higher SEM (73.83-121.98 kPa) and SDC (61.58-97.59) values than the asymptomatic group (ICC = 0.92-0.96, SEM = 49.61-103.12 kPa, SDC = 42.01-56.30) respectively. CPM's intra-rater reliability was good (ICC = 0.82) in the patients and moderate (ICC = 0.67) in the asymptomatic group, while inter-rater reliability was low for the asymptomatic group (ICC = 0.37) and extremely low (ICC = 0.074) for the patients, with comparable SEM and SDC outcomes in both groups. PPT and CPM measurements are highly reliable when conducted by the same rater on the same day. Patients had lower inter-rater PPT reliability but better intra-rater CPM reliability. Clinicians need to be mindful of potential variability when interpreting these test results.

Evidence for central sensitization as classified by the central sensitization inventory in patients with pain and hypermobility

INTRODUCTION

Pain is a very common complaint among patients with hypermobile Ehlers-Danlos Syndrome (hEDS) and Hypermobility Spectrum Disorders (HSDs). Often challenging to treat, insights into the underpinnings of pain in this population have been fleeting. Central sensitization (CS) has been postulated as a potential etiological factor.

METHODS

In this retrospective study, 82 consecutive patients with hEDS/HSDs were reviewed. Demographic information and Central Sensitization Inventory (CSI) results were collected.

RESULTS

71 of 82 (86.5%) patients demonstrated CS. Scores ranged from 12 to 94 with a median of 56. Pain scores as measured on the numerical rating scale (NRS) ranged from 2 to 10 with a mean and median of 6.

CONCLUSION

A large percentage of patients with pain and a diagnosis of hEDS/HSDs demonstrated evidence of central sensitization as measured using the CSI. The CSI is simple to administer. The CSI may provide clinical insights that are key to successfully managing patients with hEDS/HSDs. Further research is needed to explore the ability to classify pain phenotypes in this patient population and the impact on precision medicine.

Limited content overlap between commonly used self-report instruments for central (pain) sensitization in rheumatology

Objectives

Central pain mechanisms may be prominent in a considerable subset of rheumatology patients with persistent pain. Several self-report instruments have been used in previous research to infer the presence and severity of central sensitization (CS) that stem from different definitions or approaches of CS. The current study aimed to evaluate and quantify the overlap of actual symptoms measured among self-report measures of CS in rheumatology.

Methods

We used Fried's (2017) comprehensive systematic approach to analyse the content of five commonly used or typical self-report measures (Generalized Pain Questionnaire, Pain Sensitivity Questionnaire, Central Sensitization Inventory, Central Aspects of Pain in the Knee scale and the painDETECT) used in rheumatology research and to visualize and quantify the overlap in symptoms measured.

Results

The five instruments together measured 39 different symptoms, most of which could be grouped into nociplastic pain manifestations (7 symptoms), neuropathic pain qualities (5 symptoms), and psychosomatic symptoms and emotional distress (25 symptoms). Most symptoms (74.4%) were unique to a single instrument. Thermal allodynia was the most frequently measured symptom across the different instruments, assessed in four of the measures. Average content overlap was very low and ranged from no overlap at all to moderate overlap (Jaccard index = 0.43) between pairs of instruments.

Conclusion

There is high heterogeneity and limited overlap in the content of self-report measures used to infer central pain sensitization. This may lead to results that are specific to the particular instrument and may limit the generalizability and comparability of study findings in rheumatology research.

The Central Sensitization Inventory Measures Thoughts and Emotions

To determine if the Central Sensitization Inventory questionnaire (CSI) functions as a mental health measure among a cross-section of people seeking musculoskeletal specialty care, we asked: (1) What is the association of CSI total score and item groupings identified in factor analysis with mental health measures? and (2) What is the association between specific CSI items that represent each factor well and specific mental health measures? One hundred and fifty-seven adults seeking specialty care for musculoskeletal symptoms completed the CSI, a measure of catastrophic thinking, and 3 measures of distress (symptoms of health anxiety, general anxiety, and depression). Exploratory factor analysis was used to identify item groupings. Exploratory factor analysis identified 4 item groupings (factors): (1) thoughts and feelings (mental health), accounting for 52% of the variation in the CSI, (2) urinary and visual symptoms (15%) (3) body aches (10%), and (4) jaw pain (8.1%). More than half the variation in both the CSI total score (51%) and the thoughts and feelings factor (57%) were accounted for by variation in measures of catastrophic thinking and distress. Specific items that account for large amounts of the variation in the CSI also had notable correlations with mental health measures. The strong relationship between the CSI and thoughts and emotions suggests that the CSI functions largely as a mental health measure. If the concept of central sensitization is to help people get and stay healthy, it will depend on evidence that central sensitization can be measured and quantified distinct from mental health.

Pain medication tapering for patients with Persistent Spinal Pain Syndrome Type II, treated with Spinal Cord Stimulation: A RCT-study protocol of the PIANISSIMO study

BACKGROUND

Spinal Cord Stimulation (SCS) may provide pain relief in patients with therapy-refractory Persistent Spinal Pain Syndrome Type II (PSPS-T2). Despite the evidence that SCS can reduce disability and reduce pain medication usage, only 25% of the patients is able to completely omit pain medication usage after 12 months of SCS. To tackle the high burden of patients who consume a lot of pain medication, tapering programs could be initiated before starting a trajectory with SCS. The current objective is to examine whether a pain medication tapering program before SCS alters disability in PSPS-T2 patients compared to no tapering program.

METHODS AND DESIGN

A three-arm, parallel-group multicenter randomized controlled trial will be conducted including 195 patients who will be randomized (1:1:1) to either (a) a standardized pain medication tapering program, (b) a personalized pain medication tapering program, or (c) no tapering program before SCS implantation, all with a follow-up period until 12 months after implantation. The primary outcome is disability. The secondary outcomes are pain intensity, health-related quality of life, participation, domains affected by substance use, anxiety and depression, medication usage, psychological constructs, sleep, symptoms of central sensitization, and healthcare expenditure.

DISCUSSION

Within the PIANISSIMO project we propose a way to reduce the risks of adverse events, medication-induced hyperalgesia, tolerance, and dependence by providing pain medication tapering before SCS. Due to the lack of a commonly accepted in-hospital tapering approach, two different tapering programs will be evaluated in this study. If pain medication tapering programs are deemed to be more effective than no tapering on disability, this would add to the evidence towards an improved patient-centered care model in this patient group and set a clear path to advocate for pain medication tapering before SCS as the new standard treatment guideline for these patients.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05861609. Registered on May 17, 2023.

Sensory Profiles Predict Symptoms of Central Sensitization in Low Back Pain: A Predictive Model Research Study

Background: Acute low back pain has a high prevalence, and when persisting into chronicity, it results in enormous socio-economic consequences. Sensory preferences may be key factors in predicting central sensitization as the main mechanism of nociplastic pain and chronicity. Objectives: Build a model to predict central sensitization symptoms using sensory profiles based on the PROGRESS framework. Methods: A Prognostic Model Research study was carried out to predict central sensitization symptoms at 12 weeks, using baseline sensory profiles, based on 114 patients with acute low back pain. Independent variables were sensory profiles, state and trait anxiety, age, duration, pain severity, depressive symptoms, and pain catastrophizing. Results: This model, based on continuous data, significantly predicts central sensitization symptoms at 12 weeks. It contains two significantly contributing variables: sensory profile Sensory Sensitive (unstandardized B-value = 0.42; p = 0.01) and trait anxiety (unstandardized B-value = 0.53; p ≤ 0.001). The model has a predictive value of R2 = 0.38. Conclusions: This model significantly predicts central sensitization symptoms based on sensory profile Sensory Sensitive and trait anxiety. This model may be a useful tool to intervene in a bottom-up and top-down approaches to prevent chronicity in clinical practice, including individual sensory preferences and behavioral responses to sensory stimulation in rehabilitation strategies.

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

Sensory-motor training with virtual reality as a complementary intervention to manual therapy for persistent non-specific neck pain: a randomized controlled trial

BACKGROUND

Persistent non-specific neck pain (NP) is a widespread condition described as a complex biopsychosocial disorder, characterized by physical and psychological symptoms. Virtual reality (VR) shows promise in NP treatment, potentially reducing pain, kinesiophobia, and improving range of motion (ROM) and motor control.

AIM

The primary aim of the study was to assess the effectiveness of VR sensorimotor training, combined with manual therapy, in reducing the level of disability in persistent non-specific NP individuals. The secondary aim was to determine if this VR-enhanced approach also contributes to improvement in overall function, pain perception and kinesiophobia.

DESIGN

Monocentric, single-blind, randomized controlled trial.

SETTING

We conducted this trial at San Raffaele Scientific Institute, Department of Rehabilitation and Functional Recovery, Milan, Italy.

POPULATION

Forty NP participants were enrolled in the study and randomly allocated into two groups.

METHODS

The study involved a 6-week rehabilitation program, comprising 12 sessions of 45 minutes each, twice weekly. Both intervention groups underwent manual therapy as a consistent component of their treatment. The Experimental Group (VRT) was additionally engaged in sensorimotor rehabilitation exercises using Virtual Reality, whereas the Control Group (CT) performed the same exercises without VR. We assessed subjects at baseline (T0) and after six weeks of rehabilitation (T1). The primary outcome was the disability (Neck Disability Index) while the secondary outcomes were: pain perception (Numeric Rating Scale, NP and Disability Scale, Central Sensitization Inventory) function (Cervical Kinematics) and kinesiophobia (Tampa Scale of Kinesiophobia).

RESULTS

Both groups demonstrated significant reduction in level of disability, pain perception, and kinesiophobia. Significant advancements in kinematics were observed: VRT group showed enhanced ROM during craniocervical rotation (P=0.039), lateral bending (P=0.001), flexion-extension (P=0.009), and mean velocity across movements (P<0.001), whereas CT group improved in maximal ROM during lateral bending rotation (P=0.001). Between-group analysis, after Bonferroni's correction for multiple comparisons, revealed that VRT group had significantly better outcomes in ROM during rotation (P=0.040), ratio of the primary over the secondary movement while performing rotation (P=0.021), and mean velocity during lateral bending (P=0.031).

CONCLUSIONS

Sensorimotor training, combined with manual therapy, could enhance kinematic outcomes for NP patients, supporting the potential of VR in rehabilitation.

CLINICAL REHABILITATION IMPACT

This study highlighted that both groups demonstrated significant reduction in level of disability, pain perception, and kinesiophobia after sensorimotor training combined with manual therapy. It is important to underscore that in terms of reducing the level of neck disability, both interventions proved to be equally effective. This parity in efficacy is a critical finding, reaffirming the robustness of our therapeutic approaches for this specific outcome.

Temporal relationships between pain, functioning, and human assumed central sensitization in patients with chronic low back pain; a single-case design

BACKGROUND

Interdisciplinary pain rehabilitation (IPR) aims to improve functioning in people with chronic low back pain (CLBP), and is not primary aimed at pain reduction. Many patients however also report a decrease in pain. An explanation could be that IPR results in a decrease in Central Sensitization (CS). As CS is not directly assessable in humans the term Human Assumed Central Sensitization (HACS) is used in this study. It is unknown whether a decrease in HACS precedes a decrease in pain and improved functioning or vice versa.

OBJECTIVES

This study aimed to gain understanding into the temporal relationships between changes in pain, functioning, and HACS in patients with CLBP during IPR.

DESIGN

Longitudinal observational small-N-study.

METHOD

Twelve patients filled in frequently repeated self-reports 1 week before, during the 12-week IPR program, and 2 weeks after IPR. Pain was assessed by Visual Analogue Scale for pain (daily), functioning by Pain Disability Index (weekly) and Work Ability Score (daily), and HACS by Central Sensitization Inventory part A (bi-weekly). Analyses were performed by visual inspection and time series cross-correlation analyses.

RESULTS

Visual inspection showed large fluctuations within and between individual participants in patterns over time. Cross-correlation analyses showed that in most participants, relationships between pain, functioning, and HACS were strongest when analyzed at the same time (55% of comparisons). Strength and direction of (strongest) correlations showed high interindividual variability (neg: 0.33-0.97; pos: 0.22-0.99).

CONCLUSION

Overall, relationships between pain, functioning, and HACS did not show consistent temporality in patients with CLBP.

Rethinking neck-related arm pain: hypothetical clinical scenarios to differentiate the underlying IASP-defined pain mechanisms

Neck-related arm pain is frequently encountered in clinical settings, yet its underlying pain mechanisms remain elusive. While such pain radiating from the neck to the arm is often attributed to injuries or diseases of the nervous system (neuropathic pain), it can also arise from nociceptive (referred) or nociplastic sources. Regrettably, patients exhibiting this specific pain distribution are frequently diagnosed with varying terms, including 'cervicobrachialgia', 'cervicobrachial neuralgia', 'cervicobrachial pain syndrome', and 'cervical radiculopathy'. The ambiguity surrounding these diagnostic labels complicates the clinical reasoning process. It is imperative for clinicians to discern and comprehend the dominant pain mechanism. Three distinct hypothetical clinical scenarios depict patients with almost identical pain distribution but divergent dominant pain mechanisms. Within these scenarios, both subjective and objective examinations are employed to elucidate the dominant pain mechanism associated with neck-related arm pain: nociceptive, neuropathic, and nociplastic. Furthermore, clinicians must remain aware that the dominant pain mechanism can evolve over time.

Establishing central sensitization inventory cut-off values in Dutch-speaking patients with chronic low back pain by unsupervised machine learning

BACKGROUND

Human Assumed Central Sensitization (HACS) is involved in the development and maintenance of chronic low back pain (CLBP). The Central Sensitization Inventory (CSI) was developed to evaluate the presence of HACS, with a cut-off value of 40/100. However, various factors including pain conditions (e.g., CLBP), contexts, and gender may influence this cut-off value. Unsupervised clustering approaches can address these complexities by considering diverse factors and exploring possible HACS-related subgroups. Therefore, this study aimed to determine the cut-off values for a Dutch-speaking population with CLBP based on unsupervised machine learning.

METHODS

Questionnaire data covering pain, physical, and psychological aspects were collected from patients with CLBP and aged-matched healthy controls (HC). Four clustering approaches were applied to identify HACS-related subgroups based on the questionnaire data and gender. The clustering performance was assessed using internal and external indicators. Subsequently, receiver operating characteristic (ROC) analysis was conducted on the best clustering results to determine the optimal cut-off values.

RESULTS

The study included 63 HCs and 88 patients with CLBP. Hierarchical clustering yielded the best results, identifying three clusters: healthy group, CLBP with low HACS level, and CLBP with high HACS level groups. The cut-off value for the overall groups were 35 (sensitivity 0.76, specificity 0.76).

CONCLUSION

This study found distinct patient subgroups. An overall CSI cut-off value of 35 was suggested. This study may provide new insights into identifying HACS-related patterns and contributes to establishing accurate cut-off values.

Latent Profile Analysis of Canadian Military Veterans With Chronic Pain Identifies 5 Meaningful Classes Through Self-Report Measures

The purpose of this study was to identify meaningful response patterns in self-report survey data collected from Canadian military veterans with chronic pain and to create an algorithm intended to facilitate triage and prioritization of veterans to the most appropriate interventions. An online survey was presented to former members of the Canadian military who self-identified as having chronic pain. Variables collected were related to pain, physical and mental interference, prior traumatic experiences, and indicators from each of the 7 potential drivers of the pain experience. Maximum likelihood estimation-based latent profile analysis was used to identify clinically and statistically meaningful profiles using the 7-axis variables, and classification and regression tree (CRT) analysis was then conducted to identify the most parsimonious set of indicators that could be used to accurately classify respondents into the most relevant profile group. Data from N = 322 veterans were available for analysis. The results of maximum likelihood estimation-based latent profile analysis indicated a 5-profile structure was optimal for explaining the patterns of responses within the data. These were: Mood-Dominant (13%), Localized Physical (24%), Neurosensory-Dominant (33%), Central-Dominant with complex mood and neurosensory symptoms (16%), and Trauma- and mood-dominant (14%). From CRT analysis, an algorithm requiring only 3 self-report tools (central symptoms, mood screening, bodily coherence) achieved 83% classification accuracy across the 5 profiles. The new classification algorithm requiring 16 total items may be helpful for clinicians and veterans in pain to identify the most dominant drivers of their pain experience that may be useful for prioritizing intervention strategies, targets, and relevant health care disciplines. PERSPECTIVE: This article presents the results of latent profile (cluster) analysis of responses to standardized self-report questionnaires by Canadian military veterans with chronic pain. It identified 5 clusters that appear to represent different drivers of the pain experience. The results could be useful for triaging veterans to the most appropriate pain care providers.

Association of Aromatase Inhibitor-Induced Musculoskeletal Symptoms with Central Sensitization-Related Symptoms: A Cross-Sectional Study

Introduction

Aromatase inhibitor (AI)-induced musculoskeletal symptoms (AIMSS) can decrease health-related quality of life and lead to discontinuation of AI therapy for postmenopausal women with breast cancer (BC). Although central sensitization (CS) may contribute to AIMSS, the relevance of CS-related symptoms to AIMSS has not been fully clarified. This study aimed to investigate the relationship between AIMSS and CS-related symptoms in women with BC who received AI therapy.

Methods

This cross-sectional study recruited women who underwent BC surgery before at least 1 year and were taking AI for at least 6 months. Participants were assessed for joint pain and CS-related symptoms using the central sensitization inventory (CSI). The severity of CS-related symptoms was classified into three groups, and the prevalence of AIMSS was calculated. Multiple logistic regression analysis was used to assess the relationship between AIMSS and factors of possible relevance to AIMSS, including CSI severity.

Results

Of the 73 women who were included in this study, 31 (42.4%) were categorized into the AIMSS group and 42 (57.6%) into the non-AIMSS group. Participants with a history of chemotherapy and higher CSI score were significantly more likely to have AIMSS. Multiple logistic regression analysis showed that a history of chemotherapy (odds ratio = 4.21) and higher CSI severity (odds ratio = 13.43) had significantly associated with AIMSS.

Conclusion

CS-related symptoms assessed using CSI may be strongly associated with AIMSS. Further longitudinal studies to investigate the causal relationship and effectiveness of CS-targeted interventions are needed to prevent and treat AIMSS effectively.

Mechanisms of neurodynamic treatments (MONET): a protocol for a mechanistic, randomised, single-blind controlled trial in patients with carpal tunnel syndrome

BACKGROUND

Physiotherapeutic management is the first-line intervention for patients with entrapment neuropathies such as carpal tunnel syndrome (CTS). As part of physiotherapy, neurodynamic interventions are often used to treat people with peripheral nerve involvement, but their mechanisms of action are yet to be fully understood. The MONET (mechanisms of neurodynamic treatment) study aims to investigate the mechanisms of action of neurodynamic exercise intervention on nerve structure, and function.

METHODS

This mechanistic, randomised, single-blind, controlled trial will include 78 people with electrodiagnostically confirmed mild or moderate CTS and 30 healthy participants (N = 108). Patients will be randomly assigned into (1) a 6-week progressive home-based neurodynamic exercise intervention (n = 26), (2) a steroid injection (= 26), or (3) advice (n = 26) group. The primary outcome measure is fractional anisotropy of the median nerve at the wrist using advanced magnetic resonance neuroimaging. Secondary outcome measures include neuroimaging markers at the wrist, quantitative sensory testing, electrodiagnostics, and patient reported outcome measures. Exploratory outcomes include neuroimaging markers at the cervical spine, inflammatory and axonal integrity markers in serial blood samples and biopsies of median nerve innervated skin. We will evaluate outcome measures at baseline and at the end of the 6-week intervention period. We will repeat questionnaires at 6-months. Two-way repeated measures ANCOVAs, followed by posthoc testing will be performed to identify differences in outcome measures among groups and over time.

DISCUSSION

This study will advance our understanding of the mechanisms of action underpinning neurodynamic exercises, which will ultimately help clinicians to better target these treatments to those patients who may benefit from them. The inclusion of a positive control group (steroid injection) and a negative control group (advice) will strengthen the interpretation of our results.

TRIAL REGISTRATION

NCT05859412, 20/4/2023.

Differences in self-reported signs related to central sensitization and pressure pain threshold related to knee osteoarthritis and sarcopenia

PURPOSE

Neuroinflammation, which occurs in knee osteoarthritis and sarcopenia, has attracted attention as a mechanism of central sensitization, but the relationship between central sensitization and these conditions has not been widely studied. This study investigates differences in self-reported signs of central sensitization and pressure pain threshold in individuals with knee osteoarthritis and sarcopenia.

METHODS

We examined 340 patients (mean age ± standard deviation: 76 ± 5.9, women were 86.9%) with knee osteoarthritis scheduled to undergo total knee arthroplasty. For comparison, 129 community-dwelling older people (mean age ± standard deviation: 76 ± 5.5, women were 68.9%) individuals without a history of knee osteoarthritis or any other diagnosed illnesses were matched for age and sex. We assessed central sensitization inventory-9, pressure pain threshold, pain-related factors, skeletal muscle mass index, and hand grip strength. ANCOVA using 2 (patients with knee osteoarthritis and community older people without knee osteoarthritis) × 2 (sarcopenia and robust) was performed to assess outcome measurements.

RESULTS

The prevalence of sarcopenia among patients with knee osteoarthritis was 50.3%. ANCOVA revealed an interaction effect for the central sensitization inventory-9. For the main effect of knee osteoarthritis, there was a significant difference in central sensitization inventory-9, and for the main effect of sarcopenia, there was a significant difference in pressure pain threshold.

CONCLUSIONS

Discrepancies in the evaluation of central sensitization were identified between knee osteoarthritis and sarcopenia. Individuals with knee osteoarthritis had elevated score of self-reported indications of central sensitization, whereas sarcopenic patients had reduced pressure pain thresholds.

Navigating the complexity of pain in psoriatic arthritis and axial spondyloarthritis

PURPOSE OF REVIEW

Pain is the most common and often most troublesome feature of chronic autoimmune diseases such as psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA). A predominant concept is that the main source of pain is from disease-induced tissue inflammation and structural damage, activating peripheral nerve fibers which relay to the central nervous system. This mechanism is nociceptive pain and the presumption has been that controlling inflammation will be sufficient to reduce this form of pain. However, despite control of inflammation, patients may still have significant residual pain.

RECENT FINDINGS

We are learning that there are additional pain mechanisms, neuropathic and nociplastic, that are often operative in patients with rheumatologic conditions, that can significantly influence pain experience, quantitation of disease activity, and may benefit from therapeutic approaches distinct from immunotherapy. Neuropathic pain arises from diseased or damaged nerve tissue and nociplastic pain reflects sensitization of the central nervous system due to multiple genetic, neurobiologic, neural network dysregulation, and psychosocial factors. Pain arising from these mechanisms influence assessment of disease activity and thus needs to be factored into decision-making about immunotherapy efficacy.

SUMMARY

This review addresses the importance of accurately assessing the complex mechanisms of pain experience in patients with PsA and AxSpA to more appropriately manage immunomodulatory, neuromodulatory, and nonpharmacologic therapies.

How should we define and assess painful sensitivity in the hand? An international e-Delphi study

BACKGROUND

Painful sensitivity in the hand is commonly seen with neuropathic pain, interfering with daily activities including rehabilitation. However, there are currently several terms used to describe the problem and a lack of guidance on what assessments should be used.

PURPOSE

To gather expert opinion a) identifying current and common terminology used in hand therapy, b) developing a consensus definition of hypersensitivity, and c) developing consensus guidance on how to best assess allodynia.

STUDY DESIGN

International e-Delphi survey study.

METHODS

We conducted an e-Delphi consensus study drawing on international experts in hand rehabilitation. We planned up to four rounds of consensus-seeking, defining consensus as 75% or more of participants agreeing with a definition or recommendation. Experts were identified from 21 countries, with the nomination of other experts encouraged for 'snowball sampling'. The first round included clinical vignettes describing 'painful sensitivity of the hand' and asked participants to describe how they would assess each case. Definitions for hypersensitivity, tactile hyperesthesia, and allodynia were also requested.

RESULTS

We invited 68 participants: 44 more were added through nominations. Sixty-three agreed to participate and were sent the round one survey; 54 participants from 19 countries completed this survey and were invited to participate in all subsequent rounds. No two definitions of hypersensitivity were the same, while 87% of the definitions for allodynia and 78% for tactile hyperesthesia were concordant with a published taxonomy. Over 700 assessment items were proposed in round one: ultimately 38 items representing eight distinct constructs reached a consensus for assessing allodynia.

CONCLUSIONS

Therapists definitions were consistent with an existing taxonomy for allodynia. Although hypersensitivity conceptualizations varied regarding the qualities of stimulus and response, a working definition was reached. Recommended assessments were relatively consistent internationally, holistic, and reflected a potential link between allodynia and central sensitization.

Mental Health Outcomes of Endometriosis Patients during the COVID-19 Pandemic: Impact of Pre-pandemic Central Nervous System Sensitization

To correlate pain-related phenotyping for central nervous system sensitization in endometriosis-associated pain with mental health outcomes during the COVID-19 pandemic, the prospective Endometriosis and Pelvic Pain Interdisciplinary Cohort (ClinicalTrials.gov #NCT02911090) was linked to the COVID-19 Rapid Evidence Study of a Provincial Population-Based Cohort for Gender and Sex (RESPPONSE) dataset. The primary outcomes were depression (PHQ-9) and anxiety (GAD-7) scores during the pandemic. The explanatory variables of interest were the Central Sensitization Inventory (CSI) score (0-100) and endometriosis-associated chronic pain comorbidities/psychological variables before the pandemic. The explanatory and response variables were assessed for correlation, followed by multivariable regression analyses adjusting for PHQ-9 and GAD-7 scores pre-pandemic as well as age, body mass index, and parity. A higher CSI score and a greater number of chronic pain comorbidities before the pandemic were both positively correlated with PHQ-9 and GAD-7 scores during the pandemic. These associations remained significant in adjusted analyses. Increasing the CSI score by 10 was associated with an increase in pandemic PHQ-9 by .74 points (P < .0001) and GAD-7 by .73 points (P < .0001) on average. Each additional chronic pain comorbidity/psychological variable was associated with an increase in pandemic PHQ-9 by an average of .63 points (P = .0004) and GAD-7 by .53 points (P = .0002). Endometriosis patients with a history of central sensitization before the pandemic had worse mental health outcomes during the COVID-19 pandemic. As a risk factor for mental health symptoms in the face of major stressors, clinical proxies for central sensitization can be used to identify endometriosis patients who may need additional support. PERSPECTIVE: This article adds to the growing literature of the clinical importance of central sensitization in endometriosis patients, who had more symptoms of depression and anxiety during the COVID-19 pandemic. Clinical features of central sensitization may help clinicians identify endometriosis patients needing additional support when facing major stressors.

An EDucation and eXercise intervention for gluteal tendinopathy in an Irish setting: a protocol for a feasibility randomised clinical trial (LEAP-Ireland RCT)

Background

Gluteal tendinopathy (GT) is a degenerative tendon condition characterised by pain over the greater trochanter of the hip. A randomised controlled trial (RCT) in Australia found that 14 sessions of EDucation on load management plus eXercise (EDX) delivered over 8 weeks resulted in greater improvements in global rating of change and pain outcomes at 8 and 52 weeks, compared with corticosteroid injection or 'wait and see'. Typically, 5-6 physiotherapy sessions are provided in public and private physiotherapy settings in Ireland, therefore, the aim of this study is to examine the feasibility of conducting a future definitive RCT to investigate effectiveness of 6 sessions of the EDX programme compared to usual care.

Methods

We will randomly allocate 64 participants with GT to physiotherapist-administered EDX or usual care. The EDX intervention (EDX-Ireland) will be delivered in 6 sessions over 8 weeks.To determine feasibility of an RCT, we will assess recruitment and retention and outcome measure completion. The health status outcomes to be assessed at baseline, 8 weeks and 3 months include: Global Rating of Change, pain severity, the Victorian Institute of Sport Assessment-Gluteal Questionnaire (VISA-G), the Patient-Specific Functional Scale, the Pain Catastrophizing Scale, Patient Health Questionnaire (PHQ), Pain Self-Efficacy Questionnaire, the EQ-5D-5L, the Central Sensitisation Inventory and hip abductor muscle strength. We will explore acceptability of the EDX-Ireland intervention from the perspective of patients and treatment providers, and the perspective of referrers to the trial. A Study Within A Trial will be also applied to compare recording of exercise adherence using app-based technology to paper diaries.

Discussion

There is a need to establish effective treatments for GT that potentially can be implemented into existing health systems. The findings of this feasibility trial will inform development of a future definitive RCT.

Registration

The trial is registered prospectively on ClinicalTrials.gov ( NCT05516563, 27/10/2022).

Surface-Enhanced Raman Spectroscopy Combined with Multivariate Analysis for Fingerprinting Clinically Similar Fibromyalgia and Long COVID Syndromes

Fibromyalgia (FM) is a chronic central sensitivity syndrome characterized by augmented pain processing at diffuse body sites and presents as a multimorbid clinical condition. Long COVID (LC) is a heterogenous clinical syndrome that affects 10-20% of individuals following COVID-19 infection. FM and LC share similarities with regard to the pain and other clinical symptoms experienced, thereby posing a challenge for accurate diagnosis. This research explores the feasibility of using surface-enhanced Raman spectroscopy (SERS) combined with soft independent modelling of class analogies (SIMCAs) to develop classification models differentiating LC and FM. Venous blood samples were collected using two supports, dried bloodspot cards (DBS, n = 48 FM and n = 46 LC) and volumetric absorptive micro-sampling tips (VAMS, n = 39 FM and n = 39 LC). A semi-permeable membrane (10 kDa) was used to extract low molecular fraction (LMF) from the blood samples, and Raman spectra were acquired using SERS with gold nanoparticles (AuNPs). Soft independent modelling of class analogy (SIMCA) models developed with spectral data of blood samples collected in VAMS tips showed superior performance with a validation performance of 100% accuracy, sensitivity, and specificity, achieving an excellent classification accuracy of 0.86 area under the curve (AUC). Amide groups, aromatic and acidic amino acids were responsible for the discrimination patterns among FM and LC syndromes, emphasizing the findings from our previous studies. Overall, our results demonstrate the ability of AuNP SERS to identify unique metabolites that can be potentially used as spectral biomarkers to differentiate FM and LC.

Central Sensitization-Related Symptoms and Influencing Factors on Health-Related Quality of Life among Frail Older Adults in Senior Day Care Centers: A Cross-Sectional Study

The recent increase in the number of frail older adults has led to increased attention being paid to care services in communities such as senior day care centers. Maintaining health-related quality of life (HRQOL) in frail older adults is important for managing long-term care. The purpose of this study was to comprehensively explore the impact of physical, mental, and cognitive factors, particularly central sensitization-related symptoms (CSSs), on the HRQOL among frail older adults in senior day care centers. HRQOL, physical, mental, and cognitive factors, and severity of CSSs were comprehensively measured using validated methods. Correlation and multiple regression analyses were used to examine factors affecting HRQOL among frail older adults in senior day care centers. The results showed that the timed up and go test significantly affected the HRQOL among frail older adults at senior day care centers. Additionally, knee extension muscle strength, number of pain sites, depressive tendencies, and CSS severity showed a significant negative correlation with HRQOL but were not significant influencing factors. This suggests that functional mobility assessments and approaches are important for maintaining and improving the HRQOL in frail older adults at senior day care centers.

Effect of dry needling on pain and central sensitization in women with chronic pelvic pain: A randomized parallel-group controlled clinical trial

Chronic pelvic pain (CPP) is a debilitating problem in women with clear evidence of myofascial dysfunction. It seems that Myofascial trigger points (MTrPs) contribute to the development of central sensitization (CS). This study aimed to investigate the effect of dry needling on pain and CS in women with CPP. Thirty-six women with CPP participated in this randomized controlled clinical trial and randomly assigned into three groups: dry needling group (DNG), placebo needling group (PNG) and control group (CG). The DNG received five sessions of DN using the "static needling", the PNG received non-penetrating method, and the CG did not receive any intervention. Assessment of outcomes including central sensitization inventory (CSI), short-form McGill pain questionnaire (SF-MPQ), electroencephalography (EEG), conditioned pain modulation (CPM), salivary cortisol concentration, 7-item general anxiety disorder scale (GAD-7), pain catastrophizing scale (PCS), and SF-36 questionnaire was performed pre-intervention, post-intervention, and three months post-intervention by a blind examiner. The result showed a significant group-by-time interaction for CSI, SF-MPQ, and PCS. There was a significant decrease in CSI score in post-intervention and three-months post-intervention compare to pre-intervention in the DNG and PNG. SF-MPQ-PPI score in DNG significantly decreased post-intervention. PCS-Total score decreased significantly post-intervention in DNG and PNG. No significant group-by-time interactions were observed for other variables. EEG results showed regional changes in the activity of frequency bands in both eye closed and eye open conditions. It seems that DN can affect central pain processing by removing the source of peripheral nociception. Trial registration: Iranian Registry of Clinical Trials (IRCT20211114053057N1, registered on: December 03, 2021. https://irct.behdasht.gov.ir/search/result?query=IRCT20211114053057N1).