Measurement Properties of the Central Sensitization Inventory: A Systematic Review

The relationship between central sensitization and activity limitation in patients with knee osteoarthritis:The mediating role of pain catastrophizing

BACKGROUND

In patients with knee osteoarthritis, the most distressing symptom is activity limitation which exacerbates the global burden of the disease. Studies have shown that central sensitization has a negative effect on activity capabilities in patients with knee osteoarthritis. However, limited knowledge exists regarding the underlying mechanisms. Therefore, this study aimed to explore the mediating effect of pain catastrophizing on central sensitization and activity limitation among knee osteoarthritis patients.

OBJECTIVES

To explore the association between central sensitization and activity limitation by modelling three dimensions of pain catastrophizing as mediators among patients with knee osteoarthritis.

DESIGN

This is a cross-sectional study.

METHODS

A total of 392 patients were surveyed using the general demographic questionnaire, Animated Activity Questionnaire, Pain Catastrophizing Scale, and Central Sensitization Inventory. Multiple linear regression was used to determine covariates included in the mediating model. The mediating effect was tested using the SPSS PROCESS.

RESULTS

Age, duration of KOA, and K-L grade were included as covariates. The mediating model revealed that central sensitization had a direct effect on activity limitation (c' = -0.166; 95 % CI -0.271, -0.064). The relationship between central sensitization and activity limitation was primarily mediated by two indirect pathways: (1) rumination (a1b1 = -0.095; 95 % CI -0.176, -0.017) and (2) helplessness (a2b2 = -0.074; 95 % CI -0.137, -0.009). The indirect effect of the magnification dimension on activity limitation was not statistically significant (a3b3 = 0.002; 95 % CI -0.051, 0.054).

CONCLUSIONS

The study reveals rumination and helplessness in pain catastrophizing mainly mediate the relationship between central sensitization and activity limitation.

Cross-Cultural Adaptation and Validation of the Central Sensitization Inventory Into Simplified Chinese

PURPOSE

To translate the Central Sensitization Inventory from English into simplified Chinese (CSI-sC) and test the psychometric properties of the CSI-sC in patients with chronic pain.

DESIGN

A cross-sectional design was used.

METHODS

Cross-cultural adaptation of the CSI-sC was performed following Beaton's guidelines. Using a convenient sampling method, 172 patients with chronic spinal pain and 74 healthy individuals were enrolled. The Visual Analog Scale (VAS), Insomnia Severity Index (ISI), EuroQol Five Dimensions Questionnaire (EQ-5D), and Neck Disability Index (NDI) or Oswestry Disability Index (ODI) were used to measure insomnia, pain, quality of life, and functional status. Associations between CSI-sC with these measures were examined for concurrent and convergent validity assessment. Discriminant validity was confirmed by comparing CSI-sC scores between different groups. Exploratory factor analysis was used for the structural validity assessment. Reliability was assessed by internal consistency and test-retest reliability.

RESULTS

The Cronbach's alpha of the CSI-sC was 0.886. The intra-class correlation coefficient was 0.757. The CSI-sC showed a five-factor structure (57.2% of variances). The CSI-sC was significantly correlated with the ISI (r = 0.625), EQ-5D index (r = -0.363), EQ-5D health score (r = -0.355), VAS (r = 0.290), NDI (r = 0.432) and ODI (r = 0.333). CSI-sC scores were statistically higher in females compared to males (p = .006) and in the patient population compared to healthy controls (p < .001).

CONCLUSIONS

The CSI-sC demonstrated good reliability and validity in chronic spinal pain patients.

CLINICAL IMPLICATIONS

This study offers a good tool for the assessment and identification of central sensitization symptomology in clinical nursing practice, which may help optimize the treatment for patients with chronic pain.

Role of Central Sensitization Syndrome in Patients With Autonomic Symptoms

Background and Objectives

Idiosyncratic autonomic-like symptomatology, e.g., when objective autonomic tests cannot fully explain autonomic concerns, is poorly understood. We hypothesize that central sensitization plays a role in the autonomic symptoms-sings dichotomy.

Methods

This retrospective case-control study was conducted at Brigham and Women's Faulkner Hospital Autonomic Laboratory between 2022 and 2023 and analyzed patients who completed autonomic testing that included surveys (Central Sensitization Inventory [assessing central sensitization syndrome {CSS}], Compass-31 [assessing autonomic symptoms], Neuropathy Total Symptom Score-6 [assessing sensory symptoms]) and autonomic (Valsalva maneuver, deep breathing, sudomotor evaluation, and head-up tilt), cerebrovascular (cerebral blood flow velocity [CBFv]), respiratory (capnography), and neuropathic (skin biopsies for assessment of small fiber neuropathy) testing.

Results

In total, 555 patients were enrolled and 455 (78%) satisfied criteria for CSS. Patients with CSS were younger and more frequently female and had longer duration of symptoms, more comorbidities, and higher Compass-31 scores and NTSS-6 compared with non-CSS patients. Autonomic testing showed lower orthostatic end-tidal CO2 (p = 0.002) and larger orthostatic decline in CBFv (p < 0.001) in the CSS group. There was no difference in the peripheral nervous system markers (sudomotor tests and skin biopsies). The frequency of moderate autonomic failure (AF) (91.4% vs 95%, p = 0.321) was similar between the groups, but the CSS group had lower AF score (4.21 ± 3.34 vs 5.23 ± 4.08, p < 0.021).

Discussion

CSS is present in most patients with chronic autonomic concerns. Central sensitization amplifies autonomic symptoms presumably through perturbed interoceptive processing and can be an underlying mechanism driving idiosyncratic autonomic-like symptomatology. Patients with CSS had objective evidence of autonomic impairment; however, it was less severe than in non-CSS patients. Our study shows that CSS and AF coexist and both conditions need to be treated.

Symptom Duration is not Related to Central Sensitization Inventory in Midportion Achilles Tendinopathy

Background

There is concern that the prolonged symptom duration commonly observed in Achilles tendinopathy may alter pain processing and lead to development of central sensitization. If true, presence of altered pain processing could explain why nearly one third of individuals with Achilles tendinopathy do not respond to gold standard treatment. Currently, the relationship between symptom duration, symptom severity, pain, and central sensitization in Achilles tendinopathy is unclear.

Purpose

The purpose of this study was assess the proportion of individuals with midportion Achilles tendinopathy who may have central sensitization, as defined by the Central Sensitization Inventory (CSI) part A questionnaire. A secondary aim was to assess the relationship between symptom duration, pain intensity, symptom severity and CSI scores.

Study Design

Cross-Sectional Study.

Methods

Individuals diagnosed with midportion Achilles tendinopathy were included (n=182, 57% female (47.3±12.7 years). Bivariate correlations were used to evaluate relationships between symptom duration (time between date of symptom onset and date of study enrollment), symptom severity (assessed by Victorian Institute of Sport Assessment-Achilles, VISA-A), and pain intensity (assessed by Patient-Reported Outcomes Measurement Information System 29, PROMIS-29) with CSI scores.

Results

Nine of 182 individuals (4.9%, 9 females) scored above the clinical cut off for CSI, indicating likely presence of central sensitization. Duration of symptoms did not correlate with CSI score (r = 0.037, 95% CI [-.109, .181] p=0.622). VISA-A had a significant negative correlation with CSI score (r=-0.293, [-.420, -.154] p<0.001), and pain intensity had a significant positive correlation with CSI score (r=0.195, [.051, .331] p=0.008).

Conclusion

Less than five percent of individuals with midportion Achilles tendinopathy met criteria for likely presence of central sensitization as defined by the CSI screening questionnaire. The study findings suggest prolonged symptom duration among those with midportion Achilles tendinopathy is unlikely to increase the occurrence of symptoms associated with central sensitization.

Level of Evidence

Level 4.

Ageing and higher BMI explain movement control impairment distinctly better than chronic pain and its contributing factors: A cross-sectional study of 161 subjects with chronic low back pain and 42 pain-free controls

BackgroundAssessment, diagnosis, and treatment of motor control impairments are among the most widely implemented management strategies for chronic low back pain (CLBP). Low back movement control tests described by Luomajoki et al. are reliable and valid for assessing the presence and severity of motor control impairment. However, very little is known about the importance of demographic and well-established CLBP contributing factors in explaining the presence and severity of any type of motor control impairment.ObjectiveThe study objectives were to evaluate the associations of the presence and the severity of movement control impairment with age, gender, BMI, CLBP and its intensity and duration, postural stability, self-reported central sensitization, kinesiophobia, and CLBP-related disability with logistic and ordinal regressions and Wald chi-squared tests.MethodsThis cross-sectional study included 161 subjects with CLBP and 42 pain-free controls. The study was carried out in single private chiropractic clinic.ResultsHigher age and BMI were distinctly greater associated with a higher presence and severity of movement control impairment compared to the pain-related factors, namely the CLBP or its intensity or duration, central sensitization, kinesiophobia, and CLBP-related disability.ConclusionsResults highlight the importance of considering demographic factors, such as age and BMI, when interpreting motor control impairment findings. Accordingly, the findings challenge the validity of testing motor control impairment in the management of CLBP.

Pain Intensity and Pain Catastrophizing Among Patients with Chronic Pain: The Mediating Effect of Self-Efficacy

Aim

This study aimed to explore the mediating role of sense of self-efficacy in the relationship between pain intensity and pain catastrophizing among chronic pain patients.

Methods

A questionnaire survey was administered to patients with chronic pain at the pain intervention departments of three tertiary hospitals in Shaanxi Province between July 2023 and July 2024. The visual analogue scale, chronic pain self-efficacy scale, and pain catastrophizing scale were used to assess the patients' pain intensity, self-efficacy, and pain catastrophizing degree, respectively. SPSS 27.0 and Mplus 8.3 software were used for statistical analysis.

Results

This study included a total of 430 patients with chronic pain. The average score for catastrophizing pain among participants was 22.76 (score range 0-52), which is considered moderate. Pain intensity and pain catastrophizing were significantly and positively correlated, and the findings found that chronic pain self-efficacy mediated the correlation between pain intensity and pain catastrophizing after controlling for sociodemographic and disease-related variables. In addition, chronic pain self-efficacy was found to be an important mediator, accounting for 32.5% of the total effect.

Conclusion

Among patients with chronic pain, chronic pain self-efficacy explains the relationship of pain intensity and pain catastrophizing. These findings imply that interventions that decrease pain intensity and increase patients' sense of self-efficacy are beneficial for improving pain catastrophizing in this population.

Exploring Changes in Primary Motor Cortex Organization and Associations With Changes in Motor-Sensory Tests Over Time in Relation to Low Back Pain Recovery. A Longitudinal Study

The evidence for primary motor cortex reorganization in people with low back pain varies and is conflicting. Little is known about its association with motor and sensory tests, and recovery. We investigated primary motor cortex (re)organization and its associations with motor and sensory tests over time in people with (N = 25) and without (N = 25) low back pain in a longitudinal study with a 5-week follow-up. Participants with low back pain received physical therapy. Primary motor cortex organization, including the center of gravity and area of the cortical representation of trunk muscles, was evaluated using neuronavigated transcranial magnetic stimulation, based on individual magnetic resonance imaging. A motor control test (spiral tracking test) and sensory tests (quantitative sensory testing, graphaesthesia, and 2-point discrimination) were administered. Multivariate mixed models with a 3-level structure were used. In non-recovered participants, the center of gravity of longissimus L5 moved significantly anterior, and their temporal summation of pain decreased significantly more than in people without low back pain. The spiral tracking path length decreased significantly in participants without low back pain, which differed significantly from the increase in recovered participants. Significant associations were found between center of gravity and area with quantitative sensory tests and the spiral tracking test. We found a limited number of significant changes and associations over time, mainly related to longissimus L5. For some of these findings, no logical explanation seems currently available. Hence, it is unclear whether meaningful changes in cortical organization occur in people with low back pain over a 5-week period.

Improvement in Central Sensitization Following Total Knee Arthroplasty Is Associated With Severe Preoperative Pain and Affects Postoperative Quality of Life: A Retrospective Study

OBJECTIVE

Central sensitization (CS) is associated with quality of life (QOL) after total knee arthroplasty (TKA). However, how CS changes after TKA and whether these changes have clinical relevance remain unclear. Therefore, this study was conducted to identify changes in CS after TKA and to assess the clinical significance of these changes.

METHODS

This retrospective study was conducted on 92 patients between January 2021 and May 2023. CS severity was quantified using the Central Sensitization Inventory (CSI). One year after TKA, the patients were divided into groups based on whether CS severity improved by ≥ 1 level (improved group) or did not improve (non-improved group). The differences in preoperative and postoperative characteristics of patients in the two groups were analyzed. These characteristics included demographics, underlying diseases, physical examinations, and the Hospital for Special Surgery (HSS) knee score. QOL improvement was compared based on two different minimal clinically important changes (MIC) in the Short-Form Health Survey (SF-36). Continuous variables were compared using Student's t-test or the Mann-Whitney U-test. The chi-squared test was used to compare categorical variables.

RESULTS

The postoperative CS severity in patients was significantly lower compared to preoperative levels (p < 0.001). The improved group exhibited a lower HSS knee pain score (p < 0.001). Out of the eight SF-36 scales, five showed significantly greater improvement in the improved group compared to the non-improved group. The mean postoperative increases in scores for all eight SF-36 scales exceeded the MIC in the improved group, whereas half of the scales fell below the MIC in the non-improved group.

CONCLUSIONS

CS showed improvement after TKA, particularly in patients with more severe preoperative pain. This improvement appears to be correlated with the improvement in QOL after TKA.

Effectiveness of pain neuroscience education, motivational interviewing and cognition targeted exercise therapy in patients with chronic neck pain: protocol for a multicentre randomised controlled trial (the COGMO-AP study)

INTRODUCTION

In primary care, the prevalence of neck pain has increased substantially. Evidence regarding treatment of chronic neck pain (CNP) is scarce, and its effectiveness is not entirely proven in different stages of chronicity, nor for different types of cervical disorders. The goal of this study is to evaluate the effectiveness of a complex intervention (COGMO intervention) compared with usual practice in primary care physiotherapy to improve neck pain intensity, severity and disability in patients with CNP.

METHODS AND ANALYSIS

Design: a pragmatic cluster-randomised clinical trial design with a 12-month follow-up.

SETTING

primary care.

PARTICIPANTS

physiotherapists as randomisation unit, and patients as analysis unit.

INCLUSION CRITERIA

individuals aged 18 to 65 years suffering from moderate to severe CNP. Sample size expected: 142 patients. Recruitment: patients referred from primary care physicians to physiotherapy.

INTERVENTION

pain neuroscience education (PNE), motivational interviewing (MI) and cognition targeted exercise therapy (CTE) compared with the standard treatment in primary care.

OUTCOMES

the main variable is reduction in pain intensity; secondary variables include pain severity, conditioned pain modulation, temporal summation, neck disability, fear/avoidance behaviour, kinesiophobia, catastrophising, therapeutic alliance and quality of life. Sociodemographic information and adherence to the intervention will be recorded.

DATA COLLECTION

baseline, and follow-up at 3, 6 and 12 months.

ANALYSIS

it will follow intention-to-treat principles, and difference in percentage of subjects achieving success on the primary endpoint at 12 months. A model with multilevel analysis will be adjusted through logistic regression (being the dependent variable pain intensity, and the independent, the intervention).

ETHICS AND DISSEMINATION

Ethical approval has been awarded by the Regional Ethics Committee of Madrid (code: COGMO-AP) and the primary health care central commission of research (code: 20210011). The results of the study will be disseminated through international peer-reviewed journals, international conferences, press and social media.

TRIAL REGISTRATION NUMBER

NCT05785455.

Sensory profiles and their role in the persistence of central sensitization symptoms in low back pain. A prospective cohort study

INTRODUCTION

Acute lower back pain can lead to neuroplastic changes in the central nervous system, and symptoms of central sensitization after 12 weeks. While sensory sensitivity has been shown to predict symptoms of central sensitization, trait sensory profiles may be prognostic in the persistence of central sensitization symptoms in low back pain over time.

OBJECTIVE

To examine sensory profiles as prognostic symptoms of central sensitization in people with acute low back pain.

METHODS

A longitudinal type 2 prognostic factor research study was performed according to the PROGRESS framework. Baseline and 12-week follow-up measures were taken using the Adolescent/Adult Sensory Profile and the Central Sensitization Inventory measures. Study participants were consecutively included from primary care physiotherapy practices. Univariable, and multivariable regression analyses were performed to adjust sensory profiles based on previous history of low back pain, baseline Central Sensitization Inventory scores, level of pain, disability, age, and duration of low back pain.

RESULTS

After adjustment, the sensory profiles of Low Registration B = 0.44, 95%CI (0.18, 0.70), Sensation Seeking B = 0.38, 95%CI (0.19, 0.57), Sensory Sensitive B = 0.49, 95%CI (0.25, 0.74), Sensation Avoiding B = 0.40, 95% CI (0.15, 0.65) was significantly associated with the persistence of central sensitization symptoms (N = 103).

CONCLUSION

Sensory profiles may predict symptoms of central sensitization after 12 weeks in people with acute low back pain.

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.

Keeping It Simple-Pain Science Education for Patients with Chronic Pain Referred to Community-Based Rehabilitation: Translation, Adaptation, and Clinical Feasibility Testing of PNE4Adults

Background/Objectives: Pain science education accommodating low health literacy is needed for people with chronic pain. The purpose of this study was to translate PNE4Kids, contextually adapt it into PNE4Adults, and test the feasibility of the newly developed pain science education program (PNE4Adults) for adult patients with chronic musculoskeletal pain in the municipality. Methods: A three-step approach was used to (1) translate PNE4Kids into Danish, (2) adapt to age and context (PNE4Adults), and (3) test the feasibility. (1) Translation was performed by a native Dane fluent in Dutch. (2) Two think-aloud group sessions were held, with therapists and end users. (3) Feasibility was tested amongst twenty adult patients with chronic musculoskeletal pain consecutively referred for rehabilitation in the municipality. The a priori success criteria were determined to be 70% acceptability and 70% understandability. Prior to inclusion of the first patient, the study was pre-registered on clinicaltrial.gov [NCT05140031]. Results: Translation was successfully performed. Both the therapist and end users found the program easy to grasp, the simplicity and interactive nature of the program ingenious, and the program to be well suited to an adult population. All patients (100%), across health literacy levels, found PNE4Adults comprehensible and acceptable. Conclusions: The aims were successfully met. Progression to a full trial is warranted and is underway.

Sex-Specific Sensory Profiles Discriminate Between Sensitization at Twelve Weeks in Patients with Acute Low Back Pain: A Retrospective Study

Background/objective: Low back pain (LBP) is the leading cause of disability worldwide, resulting in enormous socio-economic and personal consequences. Sensory profiles during the acute back pain stage will predict central sensitization symptoms in the chronic pain stage, as central sensitization is the main mechanism behind nociplastic pain and pain chronicity. Therefore, our objective was to establish overall and sex-specific sensory profile cut-off points that distinguish symptoms of central sensitization at 12 weeks, using a retrospective prognostic cohort study design. Methods: Two hundred and seventeen patients with acute LBP (<6 weeks) were assessed using Receiver Operator Characteristic analyses. Measurements were taken at baseline using the Adolescent/Adult Sensory Profile and follow-up by the Central Sensitization Inventory at 12 weeks, based on the established Central Sensitization Inventory cut-off points for the overall population at ≥30 and ≥40, female patients at ≥33, and male patients at ≥25. Results: In female patients, a Sensory Sensitive cut-off point of ≥30.5 significantly distinguished central sensitization symptoms at 12 weeks, resulting in the following values: Area Under the Curve = 0.81 (95% CI = 0.73; 0.89), sensitivity = 0.89, specificity = 0.63, prevalence = 0.36, positive predictive value = 0.56, negative predictive value = 0.80, and Youden's index = 0.52. Conclusions: The Sensory Sensitive profile distinguishes female patients with acute LBP with and without central sensitization symptoms at 12 weeks. This cut-off point may be useful in identifying individual sensory preferences and addressing maladaptive behavioral responses to sensory stimulation in clinical practice to prevent chronicity.

Effect of central sensitization on postoperative cognitive dysfunction in total knee arthroplasty patients: a retrospective study

Background

Postoperative cognitive dysfunction (POCD) is a common complication after total knee arthroplasty (TKA), impacting recovery and quality of life. This study aims to investigate central sensitization (CS) as an independent risk factor for POCD to improve preoperative screening and postoperative interventions.

Methods

A retrospective analysis was conducted on 142 TKA patients from January 2020 to May 2024 across three hospitals. Data were collected at six time points: preoperatively (T0), intraoperatively (T1), and postoperatively on days 1 (T2), 3 (T3), 7 (T4), and 30 (T5). Patients were classified into CS (CSI ≥ 40) and non-CS (CSI < 40) groups according to Central Sensitization Inventory (CSI) score. Cognitive function and POCD incidence were assessed with the Mini-Mental State Examination (MMSE), and knee recovery with the Knee Injury and Osteoarthritis Outcome Score (KOOS). Logistic regression was used to identified risk factors for POCD.

Results

The overall incidence of POCD at T5 was 19.72%, with a significantly higher rate in CS group (30.91%) compared to non-CS group (12.64%) (p = 0.008). MMSE scores declined significantly in both groups at T2 and T3 compared to T0 (p < 0.05), with CS group showing consistently lower scores than non-CS group at T2-T5 (p < 0.05). KOOS scores revealed that CS group had worse pain and quality of life scores at T0, T4, and T5 compared with non-CS group (p < 0.05). Logistic regression revealed that CS, cerebrovascular disease, intraoperative hemorrhage, and preoperative MMSE were associated with the risk of POCD (p < 0.05).

Conclusion

CS is a significant risk factor for POCD following TKA, adversely affecting recovery in terms of pain and quality of life. Prospective studies are warranted to validate findings and develop targeted interventions.

A Mediation Appraisal of Neuropathic-like Symptoms, Pain Catastrophizing, and Central Sensitization-Related Signs in Adults with Knee Osteoarthritis-A Cross-Sectional Study

Objective. To investigate the relationships among neuropathic pain (NP), pain catastrophizing (PC), and central sensitization (CS) in relation to functional status and radiological damage in patients with knee osteoarthritis (OA). Methods. This cross-sectional study included knee OA patients derived from an observational cohort. The Spearman correlation test was used to analyze the relationship between the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the PainDetect Questionnaire (PDQ), Central Sensitization Inventory (CSI), and Pain Catastrophizing Scale (PCS). The Kruskal-Wallis test was employed to compare WOMAC scores according to CSI categories. A multivariate analysis was conducted to identify predictors of functional ability, with the WOMAC score as the dependent variable and the independent variables including pain-related indices such as PCS, PDQ, and CSI, along with Kellgren-Lawrence (K-L) grading and demographic characteristics. Results. This study included 149 patients (76.5% female; mean age 71.5 years; mean duration of pain 8.1 years). In total, 23.5% exhibited NP, 30.9% showed PC, and 33.6% had CS. Higher mean values of WOMAC were correlated with CSI categories (p < 0.0001). WOMAC showed a significant relationship with CSI (rho = 0.791; p < 0.0001), PDQ (rho = 0.766; p < 0.0001), and PCS (rho = 0.536; p < 0.0001). In the multiple regression analysis, WOMAC was independently associated with CSI (p < 0.0001), PDQ (p < 0.0001), and PC (p = 0.0001). No association was observed between the K-L grading and the other variables. Conclusions. A reduced functional capacity in patients with knee OA is correlated with the presence of NP, PC and CS, without being significantly associated with radiological damage.

The Role of Central Sensitization in Autoimmune Connective Tissue Diseases: A Comparative Cross-Sectional Study

OBJECTIVE

To investigate the central sensitization (CS) in patients with autoimmune connective tissue diseases (ACTDs) and its relationship with disease activity, laboratory findings, medical treatments, organ involvements, and comorbidity.

METHODS

One hundred and eleven patients with ACTDs and 40 healthy individuals were included. All patients were divided into three groups in terms of their diseases: Sjögren's syndrome (SS), rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE). The CS was assessed using the central sensitization inventory (CSI-A and CSI-B scores). The disease activity, laboratory findings, medical treatments, organ involvements, and comorbidity of all patients were evaluated.

RESULTS

Overall, 41.4% patients with ACTDs had CS. SS group had the highest CS positivity (n = 21, 58.3%) compared to the RA (n = 14, 36.8%) and SLE (n = 11, 29.7%) groups. The SS group had a significantly higher CSI-A score (p < 0.016) than the RA and SLE group, which had similar scores. CSI-A (p = 0.008, r = -0.63) and CSI-B (p = 0.001, r = -0.76) scores were moderately to high correlated with vitamin D3 levels in SLE group. CSI-B score was moderately correlated with folic acid levels (p = 0.03, r = 0.50) and TSH (p = 0.005, r = 0.55) in SS group. The CSI-A score ≥ 40 subgroup had more female gender, frequency of COPD or asthma, more coexisting fibromyalgia, higher VAS score, more common exocrine gland involvement, and higher corticosteroid dose compared to the CSI score < 40 subgroup.

CONCLUSIONS

CS is commonly seen in patients with ACTDs, especially in SS. CS is associated with vitamin D3, folic acid, and TSH levels in ACTD subgroups and the patients with clinical CS have a specific profile.

Complex intervention including pain science education and patient-led goal setting-based self-management strategies for management of aromatase inhibitor-induced musculoskeletal symptoms: a single-arm feasibility and pilot study

PURPOSE

Up to 74% of breast cancer survivors (BCS) treated with aromatase inhibitor (AI) experience AI-induced musculoskeletal symptoms (AIMSS). AIMSS is the predominant cause of poor adherence to AI therapy, yet no definitive treatment exists. The primary research objectives of this study were (1) to develop a novel BCS-specific complex intervention to alleviate AIMSS, and to assess its feasibility. The secondary research objective was (2) to assess the preliminary efficacy of this intervention.

METHODS

A single-arm, longitudinal pilot study was conducted involving 15 BCS with AIMSS. The complex intervention, which included pain science education, patient-led goal setting, and self-management strategies, was administered over 3 months. Feasibility was assessed by measuring overall participation, treatment completion rates, and satisfaction after 3 months of intervention. Additionally, the preliminary efficacy of the intervention was evaluated using a mixed model repeated measures analysis, with the change in pain intensity (brief pain inventory [BPI] worst pain/stiffness intensity) at 3 months as the primary endpoint.

RESULTS

The feasibility assessment showed promising results, with a 70.7% participation rate, an 83.3% intervention completion rate, and a satisfaction score of 8.2 ± 1.5. The intervention significantly reduced BPI worst pain/stiffness intensity by 2.78 points after 3 months (95% CI, - 4.5 to - 0.87, p < 0.01). Secondary outcomes demonstrated significant improvements in disability, quality of life, and pain catastrophizing (p < 0.05).

CONCLUSION

The novel complex intervention appears valuable for management AIMSS in BCS. Future large-scale studies, including randomized controlled trials, are warranted.

TRIAL REGISTRATION

The study was registered in the Clinical Trials Registry of the University Hospital Medical Information Network (UMIN-CTR: UMIN 000049035) in October 2022.

IMPLICATIONS FOR CANCER SURVIVORS

The novel BCS-specific complex intervention program holds the potential to aid in managing AIMSS, improving adherence to AI therapy, and enhancing their quality of life.

Explaining persistent physical symptoms to patients in general practice: can tests to measure central sensitisation add value? A mixed-methods study

INTRODUCTION

General practitioners (GPs) often face challenges in explaining to patients with persistent physical symptoms (PPS) why their symptoms persist. Providing an explanation of the central sensitisation (CS) mechanism to patients could be helpful, yet GPs do not routinely test for signs of CS in these patients. The aim of this study was to explore the value of applying a test to assess CS in enhancing explanations provided to patients.

METHODS

In this prospective study, 25 GPs applied three tests, selected through a Delphi study, to assess CS-related symptoms: (1) the Central Sensitisation Inventory (CSI); (2) an algometer for measuring pressure pain thresholds (PPT); and (3) a monofilament for assessing temporal summation. Following the tests, both the GP and the patient completed a short questionnaire. Subsequently, GPs shared their experiences in focus groups and interviews, while a sample of patients was interviewed individually. The questionnaires were analysed quantitatively, and the focus groups and interviews were analysed qualitatively.

RESULTS

GPs reported that all tests were feasible to perform during consultations; testing took less than 5 min in 25% of cases and between 5 and 10 min in 60% of cases. In approximately 50% of cases, an additional consultation was required to perform the test. The results of the CSI confirmed CS-related symptoms more frequently (74%) than the algometer (46%) and the monofilament (43%). Consequently, many GPs preferred the CSI. Patients did not show a preference for any specific test; two-third found the tests valuable and approximately 50% reported that the explanation of CS was clearer when a test was used.

CONCLUSIONS

Testing during the consultation was feasible, although an additional consultation was required in 50% of the cases. GPs preferred the CSI because its results confirmed CS-related symptoms more frequently than those from the algometer and monofilament.

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.

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.

The association between neuropathic pain features and central sensitization with acute headache associated to a whiplash injury

BACKGROUND

Headache is one of the most common symptoms after a whiplash injury, although the pathophysiology remains under discussion. This study aimed to evaluate differences in neuropathic pain and central sensitization features between those who present with whiplash-associated headache (WAH) soon after a whiplash injury and those who do not.

METHODS

This case-control study evaluated differences on the self-administered Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), Pain Detect Questionnaire (PDQ) and the Central Sensitization Inventory (CSI) between those who present with WAH in the acute phase after a whiplash injury (n = 46) and those who do not (n = 36). Moreover, the association of these variables in addition to neck pain intensity and the Neck Disability Index (NDI) score, with the presence of WAH was examined through logistic regression.

RESULTS

While differences between groups were found for both neuropathic and central sensitization features, only the presence of neuropathic pain features was associated with the presence of headache, with 27 scores for the S-LANSS and 23 for the PDQ from 46 people with headache (58.6% and 50.0%, respectively). The NDI and the S-LANSS partially explained (R2 = 0.68) the presence of WAH according to a logistic regression model.

CONCLUSION

Significant differences were found between people with whiplash with and without WAH when the S-LANSS, the PDQ and the CSI were assessed. S-LANSS and NDI were the variables most associated with the presence of WAH. These findings suggest that neuropathic pain features may be associated with the presence of acute WAH.

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.

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.

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.

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.

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.

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.

Reduction of Chronic Primary Low Back Pain by Spinal Manipulative Therapy is Accompanied by Decreases in Segmental Mechanical Hyperalgesia and Pain Catastrophizing: A Randomized Placebo-controlled Dual-blind Mixed Experimental Trial

Chronic primary low back pain (CPLBP) refers to low back pain that persists over 3 months, that cannot be explained by another chronic condition, and that is associated with emotional distress and disability. Previous studies have shown that spinal manipulative therapy (SMT) is effective in relieving CPLBP, but the underlying mechanisms remain elusive. This randomized placebo-controlled dual-blind mixed experimental trial (NCT05162924) aimed to investigate the efficacy of SMT to improve CPLBP and its underlying mechanisms. Ninety-eight individuals with CPLBP and 49 controls were recruited. Individuals with CPLBP received SMT (n = 49) or a control intervention (n = 49), 12 times over 4 weeks. The primary outcomes were CPLBP intensity (0-100 on a numerical rating scale) and disability (Oswestry Disability Index). Secondary outcomes included pressure pain thresholds in 4 body regions, pain catastrophizing, Central Sensitization Inventory, depressive symptoms, and anxiety scores. Individuals with CPLBP showed widespread mechanical hyperalgesia (P < .001) and higher scores for all questionnaires (P < .001). SMT reduced pain intensity compared with the control intervention (mean difference: -11.7 [95% confidence interval, -11.0 to -12.5], P = .01), but not disability (P = .5). Similar mild to moderate adverse events were reported in both groups. Mechanical hyperalgesia at the manipulated segment was reduced after SMT compared with the control intervention (P < .05). Pain catastrophizing was reduced after SMT compared with the control intervention (P < .05), but this effect was not significant after accounting for changes in clinical pain. Although the reduction of segmental mechanical hyperalgesia likely contributes to the clinical benefits of SMT, the role of pain catastrophizing remains to be clarified. PERSPECTIVE: This randomized controlled trial found that 12 sessions of SMT yield greater relief of CPLBP than a control intervention. These clinical effects were independent of expectations, and accompanied by an attenuation of hyperalgesia in the targeted segment and a modulation of pain catastrophizing.

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.

Targeted vibratory therapy as a treatment for proprioceptive dysfunction: Clinical trial in older patients with chronic low back pain

INTRODUCTION

Proprioceptive function declines with age, leading to falls, pain, and difficulties in performing activities of daily living among older adults. Although individuals with low back pain (LBP) exhibit decreased lumbosacral proprioception in various postures, the mechanism by which reduced proprioceptive function causes LBP remains uncertain. Vibratory stimulation may enhance proprioceptive function; however, its efficacy in treating LBP has not been investigated. Thus, we investigated the feasibility of improving proprioceptive function and its effect on alleviating chronic LBP in older patients through targeted vibratory therapy (TVT) administration.

METHODS

This single arm designed trial included older patients aged >65 years with non-specific chronic LBP. TVT involved applying vibratory stimulation, matching the frequency of dysfunctional receptors, for 1 min daily over 14 days to activate proprioceptors; patients performed TVT three times daily at home. In cases of reduced proprioceptive function at multiple sites, TVT was aimed at the lowest frequency band value. LBP and proprioceptive function were evaluated at 2 weeks after TVT and at 2 weeks after the end of TVT in patients with declined proprioception in the trunk or lower extremities.

RESULTS

Overall, 56 patients with chronic LBP were enrolled; 32 patients were recruited for treatment based on a proprioceptive dysfunction diagnosis and 24 patients were recruited with a normal diagnosis with no significant differences observed between the two sets of patients in sarcopenia-related factors and clinical proprioception-related characteristics. No patient had any adverse events. Two weeks after TVT, the numerical pain rating scale score improved to <3 points in 78.1% of patients, with 73.1% of patients achieving a score of ≤ 3 points. Proprioceptive function improved in 81.3% of cases, and engagement in activities of daily living improved significantly.

CONCLUSIONS

TVT demonstrated efficacy in improving proprioception and alleviating LBP in older patients with impaired proprioceptive function without affecting non-targeted proprioceptors.

Associations between pain intensity, pain sensitivity, demographics, psychological factors, disability, physical activity, pain phenotype and COVID-19 history in low back pain: An observational study

BACKGROUND AND PURPOSE

Knowledge of the factors affecting pain intensity and pain sensitivity can inform treatment targets and strategies aimed at personalizing the intervention, conceivably increasing its positive impact on patients. Therefore, this study aimed to investigate the association between demographic factors (sex and age), body mass index (BMI), psychological factors (anxiety and depression, kinesiophobia and catastrophizing), self-reported physical activity, pain phenotype (symptoms of central sensitization, and nociceptive or neuropathic pain), history of COVID-19 and pain intensity and sensitivity in patients with chronic non-specific low back pain (LBP).

METHODS

This was a cross-sectional secondary analysis with 83 participants with chronic non-specific LBP recruited from the community between August 2021 and April 2022. BMI, pain intensity (Visual Analog Scale), pain sensitivity at the lower back and at a distant point [pressure pain threshold], catastrophizing (Pain Catastrophizing Scale), kinesiophobia (Tampa Scale for Kinesiophobia), anxiety and depression (Hospital Anxiety and Depression Scale), pain phenotype (Central Sensitization Inventory and PainDetect Questionnaire), physical activity (International Physical Activity Questionnaire), and disability (Roland Morris Disability Questionnaire) were assessed. Multiple linear regression analyses with pain intensity and sensitivity as the dependent variables were used.

RESULTS

The model for pain intensity explained 34% of its variance (Adjusted R2 = -0.343, p < 0.001), with depression and anxiety (p = 0.008) and disability (p = 0.035) reaching statistical significance. The model for pain sensitivity at the lower back, also explained 34% of its variance (Adjusted R2 = 0.344, p < 0.001) at the lower back with sex, BMI, and kinesiophobia reaching statistical significance (p < 0.05) and 15% of the variance at a distant body site (Adjusted R2 = 0.148, p = 0.018) with sex and BMI reaching statistical significance (p < 0.05).

DISCUSSION

This study found that different factors are associated with pain intensity and pain sensitivity in individuals with LBP. Increased pain intensity was associated with higher levels of anxiety and depression and disability and increased pain sensitivity was associated with being a female, higher kinesiophobia, and lower BMI.

Differences in the organization of the primary motor cortex in people with and without low back pain and associations with motor control and sensory tests

Differences in organization of the primary motor cortex and altered trunk motor control (sensing, processing and motor output) have been reported in people with low back pain (LBP). Little is known to what extent these differences are related. We investigated differences in 1) organization of the primary motor cortex and 2) motor and sensory tests between people with and without LBP, and 3) investigated associations between the organization of the primary motor cortex and motor and sensory tests. We conducted a case-control study in people with (N=25) and without (N=25) LBP. The organization of the primary motor cortex (Center of Gravity (CoG) and Area of the cortical representation of trunk muscles) was assessed using neuronavigated transcranial magnetic stimulation, based on individual MRIs. Sensory tests (quantitative sensory testing, graphaesthesia, two-point discrimination threshold) and a motor test (spiral-tracking test) were assessed. Participants with LBP had a more lateral and lower location of the CoG and a higher temporal summation of pain. For all participants combined, better vibration test scores were associated with a more anterior, lateral, and lower CoG and a better two-point discrimination threshold was associated with a lower CoG. A small subset of variables showed significance. Although this aligns with the concept of altered organization of the primary motor cortex in LBP, there is no strong evidence of the association between altered organization of the primary motor cortex and motor and sensory test performance in LBP. Focusing on subgroup analyses regarding pain duration can be a topic for future research.

Evaluation of the segmental distribution of pain sensitivity among patients with central sensitization associated with chronic subacromial pain syndrome: A cross-sectional study

INTRODUCTION

Pain sensitivity is the main finding of central sensitization (CS) and can occur in patients with chronic shoulder pain. However, there is limited evidence concerning the distribution of pain sensitivity in shoulders, forearms, and legs in patients with CS associated with chronic shoulder pain. The present study aimed to determine the distribution of pain sensitivity in patients with CS associated with chronic subacromial pain syndrome (SPS).

METHOD

This cross-sectional study included 58 patients with chronic SPS and CS (patient group) and 58 healthy participants (control group). The presence of CS was determined using the Central Sensitization Inventory (CSI). To determine the distribution of pain sensitivity, pressure pain threshold (PPT) measurements were performed from the shoulders, forearms, and legs.

RESULTS

There was no significant difference between the two groups in terms of sociodemographic data (p > 0.05). The patient group had a significantly higher CSI score (p < 0.001) and lower PPTs in all regions (p < 0.05) than the control group. Unlike the control group, the patient group had lower PPTs on the affected side for the shoulder [mean difference (MD) 95% confidence interval (CI): 1.2 (-1.7 to -0.6)], forearm [MD 95% CI: 1.1 (-1.7 to -0.6)], and leg [MD 95% CI: 0.9 (-1.4 to -0.3)] compared with the contralateral side (p < 0.001).

CONCLUSION

Pain sensitivity is more pronounced in the affected shoulder and the forearm and leg located on this side than in those on the contralateral side in patients with CS associated with chronic SPS.

Is the Central Sensitization Inventory (CSI) associated with quantitative sensory testing (QST)? A systematic review and meta-analysis

Central sensitization (CS) involves an amplification of neural processing within the central nervous system that can result in widespread pain patterns and hypersensitivity to stimuli. The Central Sensitization Inventory (CSI) and various quantitative sensory testing (QST) methods purport to assess clinical markers of CS. The purpose of this systematic review and meta-analysis was to summarize and quantify the associations between total CSI scores and QST measures from previous studies. A systematic search identified 39 unique studies that were deemed eligible for the systematic review and 33 studies for meta-analyses (with 3314 subjects and 154 effect sizes), including five QST modalities: conditioned pain modulation, temporal summation, pressure pain threshold, heat pain threshold, and cold pain threshold. The meta-analysis yielded statistically significant CSI-QST correlations in total subject samples for all five QST modalities. The strongest associations were identified between CSI scores and pain threshold testing, especially pressure pain threshold, in which 51% of effects sizes, from 29 studies and 3071 subjects, were determined to be in a medium to large range.

Psychometric properties and domains covered by patient-reported outcome measures used in trials assessing interventions for chronic pain

OBJECTIVES

To identify the patient-reported outcome measures (PROMs) used in clinical trials assessing interventions for chronic pain, describe their psychometric properties, and the clinical domains they cover.

STUDY DESIGN AND SETTING

We identified phase 3 or 4 interventional trials: on adult participants (aged >18 years), registered in clinicaltrials.gov between January 1, 2021 and December 31, 2022, and which provided "chronic pain" as a keyword condition. We excluded diagnostic studies and phase 1 or 2 trials. In each trial, one reviewer extracted all outcomes registered and identified those captured using PROMs. For each PROM used in more than 1% of identified trials, two reviewers assessed whether it covered the six important clinical domains from the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT): pain, emotional functioning, physical functioning, participant ratings of global improvement and satisfaction with treatment, symptoms and adverse events, and participant disposition (eg, adherence to medication). Second, reviewers searched PubMed for both the initial publication and latest review reporting the psychometric properties of each PROM and assessed their content validity, structural validity, internal consistency, reliability, measurement error, hypotheses testing, criterion validity, and responsiveness using published criteria from the literature.

RESULTS

In total, 596 trials assessing 4843 outcomes were included in the study (median sample size 60, interquartile range 40-100). Trials evaluated behavioral (22%), device-based (21%), and drug-based (10%) interventions. Of 495 unique PROMs, 55 were used in more than 1% trials (16 were generic pain measures; 8 were pain measures for specific diseases; and 30 were measures of other symptoms or consequences of pain). About 50% PROMs had more than 50% of psychometric properties rated as sufficient. Scales often focused on a single clinical domain. Only 25% trials measured at least three clinical domains from IMMPACT.

CONCLUSION

Half of PROMs used in trials assessing interventions for chronic pain had sufficient psychometric properties for more than 50% of criteria assessed. Few PROMs assessed more than one important clinical domain. Only 25% of trials measured more than 3/6 clinical domains considered important by IMMPACT.

Psychometric properties of the Turkish version of Central Sensitization Inventory-9 in patients with chronic musculoskeletal pain

The aim of the study was to assess the psychometric properties of the Turkish version of Central Sensitization Inventory-9 (CSI-9) in patients with chronic musculoskeletal pain. The methodological study included 92 patients with chronic musculoskeletal pain. The original version of the CSI-9 was translated and culturally adapted into Turkish. The internal consistency and test-retest reliability were evaluated with Cronbach's α and the intraclass correlation coefficient (ICC), respectively. The assessment of reproducibility was conducted with the standard error of measurement (SEM) and minimal detectable difference (MDD) values. Convergent validity was explored by correlation analysis between the CSI-9 and Central Sensitization Inventory (CSI-25), Brief Pain Inventory (BPI), and European Quality of Life Survey-5 Dimensions (EQ-5D). The structural validity was assessed with factor analysis. Floor and ceiling effects were also analyzed. We found a very good internal consistency (Cronbach's α of 0.83) and excellent test-retest reliability (ICC of 0.96) of the Turkish CSI-9. The SEM demonstrated a range between 0.19 and 1.12, and the MDD was observed to vary from 1.17 to 1.35. The CSI-9 correlated significantly with the CSI-25 ( r  = 0.77, P  < 0.001), the pain severity subscale of the BPI ( r  = 0.41 to 0.53, P  < 0.001), the pain interference subscale of the BPI ( r  = 0.21 to 0.58, P  = 0.02 to P  < 0.001), the EQ-5D ( r  = 0.24 to 0.48, P  < 0.05), and the EQ-5D visual analog scale ( r  = -0.41, P  < 0.001). One factor was identified within the CSI-9. Our data suggest that the Turkish CSI-9 is reliable and valid outcome measure for assessing CS in patients with chronic musculoskeletal pain.

Efficacy of a Psychologically-Informed Physiotherapy Intervention in Patients with Chronic Low Back Pain at High Risk of Poor Prognosis: A Pilot and Feasibility Randomized Controlled Trial

Purpose

To determine the feasibility of a randomized controlled trial (RCT) testing the efficacy of psychologically-informed physiotherapy (PIPT), which includes usual physiotherapy (UP) interventions, compared with UP, and to explore the preliminary effectiveness of the interventions.

Method

People with chronic low back pain at high risk of poor prognosis (using the STarT Back screening tool) were recruited and allocated to PIPT or UP. Effectiveness of recruitment strategies, adherence to intervention, risk of contamination, and specific challenges were assessed. Functional capacity, pain, quality of life, kinesiophobia, catastrophization, central sensitization, and self-efficacy were measured at baseline, 6-, 12- and 24-week follow-ups.

Results

Forty participants were recruited mainly by diffusing through Laval University's email list, and 10 physiotherapists treated the participants recruited. The retention rate of participants at 24 weeks was 72.5%. Adherence to treatment by participants and physiotherapists was very good. The risk of contamination was low, and the specific challenges identified were modifiable. Significant improvement over time in all clinical variables of interest, except self-efficacy, was observed with no difference between groups.

Conclusions

As most success criteria were met, conducting an RCT evaluating PIPT and PU is feasible with modifications. PIPT and UP appear to be similarly effective.

Prevalence and Severity of Central Sensitization in Post-Polio Syndrome: Associations with Clinical Measures and Quality of Life

OBJECTIVES

To investigate the presence and severity of central sensitization (CS) and its associations with clinical measures and quality of life (QoL) in individuals with a history of paralytic poliomyelitis with and without post-polio syndrome (PPS).

METHODS

In this cross-sectional study, we included 98 individuals with a history of poliomyelitis, in whom 82 (83.6%) met the criteria of PPS. We used CS Inventory (CSI) to evaluate the presence and severity of CS. We evaluated the severity of fatigue, pain, polio-related impairments, and QoL using a Numerical Rating Scale in addition to Fatigue Severity Scale, Self-reported Impairments in Persons with late effects of Polio rating scale (SIPP), and Nottingham Health Profile (NHP).

RESULTS

CS was present in 52.4% of patients with PPS, of which 63% are classified as severe to extreme. Those with CS reported more severe symptoms, more polio-related impairments, and worse QoL than those without CS. Severity of CS showed significant positive correlations with severity of fatigue, pain, SIPP, and NHP scales in those with PPS. CSI did not indicate CS in any of those without PPS.

CONCLUSION

CS was present in more than half of the individuals with PPS and correlated with more severe pain, fatigue, and more polio-related impairments, in addition to poorer QoL. These findings suggest that CS may contribute to the clinical picture in a subgroup of individuals with PPS. Thus, identification and appropriate management of CS patients may potentially help alleviate their symptoms and improve their QoL.

Impaired Carbohydrate Metabolism among Women with Chronic Low Back Pain and the Role of Dietary Carbohydrates: A Randomized Controlled Cross-Over Experiment

Background: Impaired glucose regulation is suggested to be related to chronic low back pain (CLBP), although it is not clear how they interact with each other. Thus, the primary aim of this study was to investigate differences in postprandial glycemic responses (PPGRs) (the first sign of impaired glucose metabolism) to high- (sucrose) and low-glycemic index (GI) (isomaltulose) beverages in normoglycemic women with CLBP and healthy controls (HCs) and explore whether any group that showed greater PPGRs to high-GI beverage intake would benefit when the high-GI beverage was replaced with a low-GI beverage. Secondly, this study aimed to explore the association between PPGR and pain in patients with CLBP. Methods: This study was registered at clinicaltrials.org (NCT04459104) before the start of the study. In this study, 53 CLBP patients and 53 HCs were recruited. After 11-12 h of fasting, each participant randomly received isomaltulose or sucrose. Blood glucose levels were measured during the fasting state and 15, 30, 45, 60, 90, and 120 min after the beverage intake, and each participant underwent experimental pain measures. Results: Compared to the HCs, the CLBP group showed significantly higher PPGRs to sucrose (p < 0.021). Additionally, the CLBP group showed a significantly higher decrease in PPGR (p = 0.045) when comparing PPGR to sucrose with PPGR to isomaltulose. Correlation analysis revealed a positive association between self-reported pain sensitivity and PPGR to sucrose, while there was no association found between any experimental pain measures and glycemic responses. Conclusions: Overall, these findings suggest that normoglycemic CLBP patients might have a higher risk of developing impaired glucose tolerance than the HCs and might benefit more when high-GI foods are replaced with low-GI ones.

Sensitization-Associated Symptoms and Neuropathic-like Features in Patients with Cervical Dystonia and Pain

Background: This exploratory study evaluated the presence of sensitization-associated and neuropathic-like symptoms and identified their association with pressure sensitivity, pain, and disability in patients with cervical dystonia (CD). Methods: Thirty-one patients with CD (74.2% women, age: 61.2 years, SD 10.1) participated. Data collected included clinical variables, the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS), the Central Sensitization Inventory (CSI), the Self-administered Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS), the Hospital Anxiety and Depression Scale (HADS) and the Pittsburgh Sleep Quality Index (PSQI), as well as widespread pressure pain thresholds (PPTs). Results: Patients with CD with pain (n = 20, 64.5%) showed higher scores on the TWSTRS disability subscale and the CSI (p < 0.001), and lower PPTs (p < 0.05). Fifteen patients (15/31, 48%) showed sensitization-associated symptoms (CSI ≥ 40), whereas five of the patients with pain (5/20, 25%) exhibited neuropathic-like symptoms (S-LANSS ≥ 12). The CSI and S-LANSS were positively associated with the TWSTRS, HADS-A and HADS-D, and negatively associated with PPTs. HADS-D and S-LANSS explained 72.5% of the variance of the CSI (r2: 0.725), whereas CSI explained 42.3% of the variance of the S-LANSS (r2: 0.423). Conclusions: Pain is an important source of disability in CD, and may be a consequence of different mechanisms, including sensitization.

Association between smoking and central sensitization pain: a web-based cross-sectional study

PURPOSE

This study aimed to investigate whether smoking is an independent risk factor for central sensitization syndrome (CSS) in individuals with pain as measured by the Central Sensitization Inventory (CSI).

METHODS

In 2020, we conducted an Internet survey targeting 2000 ordinary residents of Japan (aged 20-69 years) who had pain symptoms from October to November 2020. A multiple regression analysis was performed on the association between smoking status (nonsmokers and current smokers; Brinkman index) and CSI values. Moreover, compared to nonsmokers, the relative risk (RR) of the CSI cut-off score of 40 points or higher among current smokers was calculated using a modified Poisson regression model. Covariates included age, sex, body mass index, marital status, equivalized income, exercise habits, history of hypertension, history of hyperlipidemia, history of diabetes, pain chronicity, and Pain Catastrophizing Scale score.

RESULTS

This study analyzed 1,822 individuals (1,041 men and 781 women). Among those experiencing pain, current smoking was associated with the increase in CSI values (β = 0.07). The Brinkman index was also significantly associated with the increase in CSI values (β = 0.06). Current smoking also increased the risk of being over the CSI cut-off score, with a relative risk (RR) of 1.29 (95% confidence intervals, 1.04-1.60). Younger age, being women, experiencing chronic pain, and higher pain catastrophizing thinking were also significantly associated with increased CSS severity, independent of smoking status.

CONCLUSION

Smoking is an independent risk factor for CSS. This indicates that smoking may be an important factor in the management of central pain disorders.

To what degree patient-reported symptoms of central sensitization, kinesiophobia, disability, sleep, and life quality associated with 24-h heart rate variability and actigraphy measurements?

OBJECTIVES

Chronic musculoskeletal pain is associated with decreased parasympathetic and increased sympathetic activity in the autonomic nervous system. The objective of this study was to determine the associations between objective measures of heart rate variability (a measure of autonomic nervous system function), actigraphy (a measure of activity and sleep quality), respiration rates, and subjective patient-reported outcome measures (PROMs) of central sensitization, kinesiophobia, disability, the effect of pain on sleep, and life quality.

METHODS

Thirty-eight study subjects were divided into two subgroups, including low symptoms of central sensitization (n = 18) and high symptoms of central sensitization (n = 20), based on patient-reported scores on the Central Sensitization Inventory (CSI). Heart rate variability (HRV) and actigraphy measurements were carried out simultaneously in 24 h measurement during wakefulness and sleep.

RESULTS

A decrease in HRV during the first 2 h of sleep was stronger in the low CSI subgroup compared to the high CSI subgroup. Otherwise, all other HRV and actigraphy parameters and subjective measures of central sensitization, disability, kinesiophobia, the effect of pain on sleep, and quality of life showed only little associations.

DISCUSSION

The high CSI subgroup reported significantly more severe symptoms of disability, kinesiophobia, sleep, and quality of life compared to the low CSI subgroup. However, there were only small and nonsignificant trend in increased sympathetic nervous system activity and poorer sleep quality on the high central sensitization subgroup. Moreover, very little differences in respiratory rates were found between the groups.

Questionnaires for the Assessment of Central Sensitization in Endometriosis: What Is the Available Evidence? A Systematic Review with a Narrative Synthesis

It has been suggested that central sensitization (CS) may be involved in the failure of standard medical and surgical treatment to relieve endometriosis-related pain. However, there is no gold standard for the diagnosis of CS, and self-reported questionnaires are used as diagnostic surrogates. The main objective of this review was to identify all CS questionnaires used in clinical endometriosis studies. The secondary objective was to qualitatively analyze strengths and weaknesses of each questionnaire. A PubMed and EMBASE systematic literature search conducted in April 2023 using the terms "endometriosis; central pain; central sensitization; questionnaire; patient-reported outcome measure; screening tool" identified 122 publications: six articles were included in the review. The Central Sensitization Inventory (CSI) is the most frequently used questionnaire for the detection of CS in patients with endometriosis. It has been validated in patients with endometriosis, in whom it appears to have good psychometric proprieties. The Fibromyalgia Survey Questionnaire (FSQ) has also been used, although it has not been specifically validated in endometriosis patients. The debate regarding these questionnaires' construct validity is still open and will be so until a gold standard diagnostic tool for CS is found. In fact, some authors argue these questionnaires are measuring psychological vulnerability and a hypervigilant state that is associated with pain, rather than CS itself. However, their use should not be discouraged as they are able to identify chronic pain patients which warrant further attention and who may benefit from broader treatment strategies.

Nociceptive, neuropathic, or nociplastic low back pain? The low back pain phenotyping (BACPAP) consortium's international and multidisciplinary consensus recommendations

The potential to classify low back pain as being characterised by dominant nociceptive, neuropathic, or nociplastic mechanisms is a clinically relevant issue. Preliminary evidence suggests that these low back pain phenotypes might respond differently to treatments; however, more research must be done before making specific recommendations. Accordingly, the low back pain phenotyping (BACPAP) consortium was established as a group of 36 clinicians and researchers from 13 countries (five continents) and 29 institutions, to apply a modified Nominal Group Technique methodology to develop international and multidisciplinary consensus recommendations to provide guidance for identifying the dominant pain phenotype in patients with low back pain, and potentially adapt pain management strategies. The BACPAP consortium's recommendations are also intended to provide direction for future clinical research by building on the established clinical criteria for neuropathic and nociplastic pain. The BACPAP consortium's consensus recommendations are a necessary early step in the process to determine if personalised pain medicine based on pain phenotypes is feasible for low back pain management. Therefore, these recommendations are not ready to be implemented in clinical practice until additional evidence is generated that is specific to these low back pain phenotypes.

Towards comprehensive management of symptomatic endometriosis: beyond the dichotomy of medical versus surgical treatment

Except when surgery is the only option because of organ damage, the presence of suspicious lesions, or the desire to conceive, women with endometriosis-associated pain often face a choice between medical and surgical treatment. In theory, the description of the potential benefits and potential harms of the two alternatives should be standardized, unbiased, and based on strong evidence, enabling the patient to make an informed decision. However, doctor's opinion, intellectual competing interests, local availability of specific services and (mis)information obtained from social media, and online support groups can influence the type of advice given and affect patients' choices. This is compounded by the paucity of robust data from randomized controlled trials, and the anxiety of distressed women who are eager to do anything to alleviate their disabling symptoms. Vulnerable patients are more likely to accept the suggestions of their healthcare provider, which can lead to unbalanced and physician-centred decisions, whether in favour of either medical or surgical treatment. In general, treatments should be symptom-orientated rather than lesion-orientated. Medical and surgical modalities appear to be similarly effective in reducing pain symptoms, with medications generally more successful for severe dysmenorrhoea and surgery more successful for severe deep dyspareunia caused by fibrotic lesions infiltrating the posterior compartment. Oestrogen-progestogen combinations and progestogen monotherapies are generally safe and well tolerated, provided there are no major contraindications. About three-quarters of patients with superficial peritoneal and ovarian endometriosis and two-thirds of those with infiltrating fibrotic lesions are ultimately satisfied with their medical treatment although the remainder may experience side effects, which may result in non-compliance. Surgery for superficial and ovarian endometriosis is usually safe. When fibrotic infiltrating lesions are present, morbidity varies greatly depending on the skill of the individual surgeon, the need for advanced procedures, such as bowel resection and ureteral reimplantation, and the availability of expert colorectal surgeons and urologists working together in a multidisciplinary approach. The generalizability of published results is adequate for medical treatment but very limited for surgery. Moreover, on the one hand, hormonal drugs induce disease remission but do not cure endometriosis, and symptom relapse is expected when the drugs are discontinued; on the other hand, the same drugs should be used after lesion excision, which also does not cure endometriosis, to prevent an overall cumulative symptom and lesion recurrence rate of 10% per postoperative year. Therefore, the real choice may not be between medical treatment and surgery, but between medical treatment alone and surgery plus postoperative medical treatment. The experience of pain in women with endometriosis is a complex phenomenon that is not exclusively based on nociception, although the role of peripheral and central sensitization is not fully understood. In addition, trauma, and especially sexual trauma, and pelvic floor disorders can cause or contribute to symptoms in many individuals with chronic pelvic pain, and healthcare providers should never take for granted that diagnosed or suspected endometriosis is always the real, or the sole, origin of the referred complaints. Alternative treatment modalities are available that can help address most of the additional causes contributing to symptoms. Pain management in women with endometriosis may be more than a choice between medical and surgical treatment and may require comprehensive care by a multidisciplinary team including psychologists, sexologists, physiotherapists, dieticians, and pain therapists. An often missing factor in successful treatment is empathy on the part of healthcare providers. Being heard and understood, receiving simple and clear explanations and honest communication about uncertainties, being invited to share medical decisions after receiving detailed and impartial information, and being reassured that a team member will be available should a major problem arise, can greatly increase trust in doctors and transform a lonely and frustrating experience into a guided and supported journey, during which coping with this chronic disease is gradually learned and eventually accepted. Within this broader scenario, patient-centred medicine is the priority, and whether or when to resort to surgery or choose the medical option remains the prerogative of each individual woman.

The relationship of behavioral and psychological traits with pain sensitivity in females with patellofemoral pain: A cross-sectional study

OBJECTIVE

The purpose of this study was to describe the relationship between behavioral and psychological traits with indicators of central sensitization in female runners with patellofemoral pain (PFP), and to determine if behavioral and psychological traits improve with strength training.

DESIGN

Cross-sectional study.

SETTING

University laboratory.

PARTICIPANTS

Twenty-eight active females (mean age 32 ± 8.1 years) with PFP completed testing at baseline, 8 weeks (post intervention), and 12 weeks.

MAIN OUTCOME MEASURES

Behavioral and psychological questionnaires included the General Anxiety Disorder-7, Patient Health Questionairre-9, Pain Catastrophizing Scale, Tampa Scale of Kinesiophobia-11, and Central Sensitization Inventory. Quantitative sensory testing (QST) measures were also collected. After baseline testing, subjects were instructed in a hip and knee strengthening intervention to be completed twice daily over 8 weeks.

RESULTS

A statistically significant improvement was found at 12 weeks for anxiety (p = .015; ηp (Boling et al., 2010) = 0.099) and kinesiophobia (p = .041; ηp (Boling et al., 2010) = 0.076). There was no significant improvement for depression, catastrophizing, or subjective central sensitization. No significant correlations were found between any of the behavioral and psychological questionnaires with baseline QST variables.

CONCLUSIONS

No relationship was found for behavioral and psychological characteristics with QST measures in female runners with persistent PFP.

Proinflammatory Dietary Intake Relates to Pain Sensitivity in Chronic Nonspecific Low Back Pain: A Case-Control Study

Nonspecific chronic low back pain (nCLBP) has been associated with nutrition. Yet, it is not clear how nutritional factors and nCLBP relate to one another. Therefore, the aim of the present study was to investigate differences in diet quality and dietary intake levels between nCLBP patients and healthy controls (HCs) and explore the association between nutritional factors and pain sensitivity in nCLBP. In this case-control study, 106 participants (ie, n = 53 nCLBP and n = 53 HCs) were recruited and completed a 3-day food diary to assess their dietary intake, which allowed to generate individual diet quality scores (ie, the Healthy Eating Index-2015 and Dietary Inflammatory Index). Additionally, each participant underwent an experimental pain assessment (quantitative sensory testing) and filled out self-reported pain questionnaires. Compared to HCs, the nCLBP group showed significantly lower diet quality, higher inflammatory scores, and a lower intake of total protein, total fat, dietary fiber, omega-3 fatty acids, vitamin B6, vitamin A, beta-carotene, vitamin E, and magnesium. Pain sensitivity mainly showed a negative correlation with nutritional intakes known for anti-inflammatory properties (ie, vitamins E, D, A, B6, B12, and zinc). Interestingly, total fat, cholesterol, saturated, and monounsaturated fat intakes were found to be inversely associated with pain sensitivity. Overall, patients with nCLBP have a lower diet quality, eat more proinflammatory, have less intake of nutrients known for their anti-inflammatory and antioxidative properties, and drink less water compared to HCs. Accordingly, pain sensitivity was mainly found to be positively associated with proinflammatory dietary intake. PERSPECTIVE: This study emphasizes the association between a proinflammatory diet and nCLBP. Among nCLBP patients, positive association between increased pain sensitivity and the proinflammatory potential of a diet, highlighting the potential for individualized pain management strategies and leading to the development of novel therapeutic methods.

Central Sensitization in Psoriatic Arthritis: Relationship With Composite Measures of Disease Activity, Functional Disability, and Health-Related Quality of Life

OBJECTIVE

To investigate the prevalence of central sensitization (CS) in patients with psoriatic arthritis (PsA) and its association with disease activity and patient-reported outcome measures.

METHODS

This cross-sectional study included adults with PsA without coexisting fibromyalgia (FM). Patients underwent a clinimetric assessment to collect variables regarding disease activity, quality of life (QOL), functional ability, impact of disease, and CS. Spearman ρ was used to examine the relationship between CS Inventory (CSI) scores and other variables. A multivariate analysis was performed to determine the independent contribution of each variable to the 12-item Psoriatic Arthritis Impact of Disease (PsAID-12) score.

RESULTS

One hundred fifty-seven patients were enrolled. Of them, 45.2% scored a CSI ≥ 40, indicating a high probability of CS. Significant correlations were found between CSI and disease activity, as evaluated by Disease Activity in Psoriatic Arthritis score and Psoriatic Arthritis Disease Activity Score (ρ 0.587 and ρ 0.573, respectively), between CSI and the Health Assessment Questionnaire (ρ 0.607), and between CSI and the 36-item Short Form Health Survey physical component summary and mental component summary scores (ρ -0.405 and ρ -0.483, respectively). In multivariate analysis, CSI score was the principal independent variable (P < 0.001) contributing to PsAID-12 score.

CONCLUSION

Patients with PsA with symptoms of CS had higher disease activity, worse functional ability, and worse QOL. The presence of CS is the major contributor in the impact of disease.

Exercise-Induced Hypoalgesia in Patients with Chronic Whiplash-Associated Disorders: Differences between Subgroups Based on the Central Sensitization Inventory

BACKGROUND

Physical exercise is an important element in the rehabilitation of chronic whiplash-associated disorders, with the physiological process underlying pain reduction called exercise-induced hypoalgesia. In chronic whiplash-associated disorders, exercise-induced hypoalgesia appears impaired, and the research suggests a relationship with symptoms of dysfunctional nociceptive processing, such as central sensitization. This study improves our understanding of exercise-induced hypoalgesia in chronic whiplash-associated disorders by examining the differences between the extent of exercise-induced hypoalgesia in subgroups based on scores on the central sensitization inventory (CSI).

METHODS

Data were collected from 135 participants with chronic whiplash-associated disorders who completed a set of questionnaires. Pain pressure thresholds and temporal summations were assessed before and after a submaximal aerobic bicycle exercise test.

RESULTS

We observed no interaction effect between exercise-induced hypoalgesia and the CSI scores for both pain pressure threshold and temporal summation. No overall statistical effect was measured in the analysis of the effect of time. The pain pressure threshold significantly related to the CSI. The temporal summation showed no correlation.

CONCLUSIONS

During this study, we did not find evidence for a difference in the presence of exercise-induced hypoalgesia when the subgroups were created based on the central sensitization cluster calculator. Limited evidence was found for the influence of CSI scores on the delta pain pressure threshold.