Applying Modern Pain Neuroscience in Clinical Practice: Criteria for the Classification of Central Sensitization Pain

Altered Brain Functional Connectivity and Neurometabolite Correlations in Orofacial Chronic Pain with Central Sensitization

Purpose

Central sensitization (CS) is one of the causes of refractory chronic orofacial pain (COFP). Chronic pain reportedly alters resting-state functional connectivity (FC) in the brain. The salience network (SN) overlaps with brain regions involved in chronic pain. Moreover, excitatory and inhibitory neural activities can alter FC. This study investigated the correlations between FC of the SN and other neural circuits, neurometabolites in anterior cingulate cortex (ACC), and CS Inventory (CSI) scores.

Patients and Methods

Participants were 21 COFP patients and 21 healthy sex- and age-matched volunteers. We conducted a combined study of CSI scores, resting-state functional magnetic resonance imaging, and proton magnetic resonance spectroscopy of ACC.

Results

FC between the nucleus accumbens within the mesolimbic system and SN regions was significantly stronger in patients compared with that in controls. In patients, the results revealed positive correlations between CSI scores and FC in four pairs of regions: ACC-right putamen and ACC-right globus pallidus, left insula-right putamen, and right anterior supramarginal gyrus-right lateral prefrontal cortex. Regarding correlations between neurometabolites in ACC and FC between ACC and other cortical regions, the results revealed that bilateral ACC-anterior insula FC was negatively correlated with glutamate, glutamine, and glutathione. Additionally, aspartate, an N-methyl-D-aspartic acid receptor agonist, was negatively correlated with FC of ACC-right parietal cortex in the default mode network. Regarding FC of bilateral ACC-posterior parietal cortex in the frontoparietal network, FC on the right side was positively correlated with glutathione associated with excitatory neuronal activity, whereas that on the left side was negatively correlated with gamma-aminobutyric acid / total creatine associated with inhibitory neural activity.

Conclusion

Connectivity within the SN, and between the SN and the mesolimbic system and other networks, may be involved in CS in COFP. Neurometabolites in the ACC may modulate FC linked to the ACC.

Longitudinal study of central sensitization and chronic low back pain in a Japanese cohort during the COVID-19 pandemic

This study utilized a longitudinal survey in Japan to investigate whether higher Central Sensitization Inventory (CSI) scores, serving as a proxy for central sensitization-related symptoms, are associated with an increased risk of developing chronic low back pain (CLBP), focusing on the impact of the coronavirus disease (COVID-19) pandemic on these conditions. Healthy volunteers (n = 227; mean age: 68.5 ± 9.5 years) were surveyed at baseline (July 2019) and at follow-up (October 2020). The participants were categorized into four groups based on their CLBP status: None, De novo, Continued, and Improved. CLBP prevalence increased from 26% at baseline to 32% at follow-up. Higher baseline CSI scores (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.02-1.09; p = 0.005) and older age (OR 1.06, 95% CI 1.02-1.11; p = 0.007) were identified as significant risk factors for developing CLBP. The mean CSI scores exhibited a slight non-significant increase from 16.9 ± 11.4 to 17.1 ± 11.7. Participants who adhered more strictly to the COVID-19 guidelines and engaged in reduced physical activity reported a higher CLBP prevalence. Our findings suggest that early identification and management of central sensitization are crucial for improving clinical outcomes, particularly during periods of external stress, such as the COVID-19 pandemic.

Effect of pain neuroscience education+ (PNE+) in people with different mechanisms of chronic pain: A systematic review and meta-analysis

BACKGROUND

Chronic pain poses a multifaceted and prevalent challenge that significantly affects an individual's quality of life. Sensory mechanisms, behavioural components (kinesiophobia and catastrophising), and social factors can influence pain perception in both younger and older populations. Moreover, the mechanisms underlying these altered pain phenotypes require further investigation in order to plan appropriate treatment. While Pain Neuroscience Education (PNE) has proven effective in managing chronic pain and previous research has been conducted on PNE physiotherapeutic techniques, there remains insufficient evidence on the efficacy of these adjunctive treatments.

OBJECTIVE

The objective of the present systematic review and meta-analysis was to evaluate the evidence for the efficacy of PNE + PT (PNE+) on pain as a primary outcome and 12 other psychosocial variables as secondary outcomes in patients with different pain mechanisms, and whether PNE+ could be applied to painful diabetic neuropathy.

METHODS

A thorough literature search was conducted in the database Scopus, MEDLINE/PubMed, ScienceDirect, CINAHL, and Web of Science, using keywords like "Pain Neuroscience Education", and "Chronic Pain" from 2010 to 2024 based on inclusion and exclusion criteria. Twenty of the 2558 studies that underwent screening qualified for a meta-analysis and 24 of them for a systematic review. Cochrane Risk of Bias 2 was used to assess the quality of the studies. Forest plots were generated using the Revman 5.3 software.

RESULTS

Studies that predominantly addressed central sensitization and neuropathic pain demonstrated moderate-to good-quality evidence. The review findings indicate that PNE+ is effective in reducing experienced pain intensity and experienced pain interference on the Visual Analogue Scale (VAS: SMD -0.70, 95% CI -1.26 to -0.14), Numerical Pain Rating Scale (NPRS SMD -1.71, 95% CI -2.34 to -1.08), reduced kinesiophobia (Tampa scale of Kinesiophobia: SMD -5.29, 95% CI -7.33 to -3.25), and catastrophizing (pain catastrophizing scale: -3.82, 95% CI -6.44 to -1.21).

CONCLUSION

PNE + has been found to be an effective intervention for reducing perceived pain experience, pain interference and other psychosocial variables in the management of chronic pain with different pain mechanisms. Most studies have focused on central sensitization, urging future research to explore PNE+ efficacy in neuropathic pain, such as painful diabetic neuropathy.

PROSPERO REGISTRATION NUMBER

CRD42023451101.

Association between central sensitization and multisite pain in the general population: A cross-sectional analysis of The Wakayama Health Promotion Study

BACKGROUND

Central sensitization (CS), which is characterized by amplified nociceptive processing within the central nervous system, is a key mechanism underlying chronic pain disorders. Chronic pain is a significant global health issue; however, the relationship between CS and pain distribution in the general population remains unclear. This study aimed to investigate the association between CS and the number of locations of body pain in a representative sample of the general population.

METHODS

This cross-sectional study included 739 participants (340 men, 399 women) from the Wakayama Health Promotion Study. CS was assessed using the Japanese version of the Central Sensitization Inventory (CSI-J), with scores of ≥30 indicating CS. Participants reported pain at 13 locations. Statistical analyses, including chi-square tests, Student's t-tests, and multiple regression analyses, were performed to determine the associations between Central Sensitization Inventory (CSI) scores and pain locations.

RESULTS

Among the participants, 9.5 % were diagnosed with CS. Females had significantly higher CSI scores than males. Lower back pain (20.6 %) and shoulder pain (15.0 %) were most common in men, whereas shoulder pain (20.6 %), knee pain (20.1 %), and lower back pain (19.5 %) were most common in women. Multivariate analysis revealed that sex, headache, neck pain, shoulder pain, arm pain, lower back pain, hip pain, thigh pain, and knee pain were significantly associated with CSI scores. Participants with ≥3 locations were 14.4 times more likely to have CS.

CONCLUSIONS

This study highlights the significant prevalence of CS in the general population, with a higher prevalence in females. Specific locations of pain, particularly those close to the trunk, are strongly associated with CS. These findings underscore the importance of assessing CS in individuals with multisite pain for targeted management and treatment strategies.

Applying Nociplastic Pain Criteria in Chronic Musculoskeletal Conditions: A Vignette Study

Background/Objectives: The International Association for the Study of Pain (IASP) recently introduced clinical criteria and a grading system to identify nociplastic pain, marking a pivotal step toward improving diagnostic accuracy. This study aimed to evaluate the reliability and validity of the IASP criteria using clinical vignettes, assessing their effectiveness in identifying nociplastic pain in clinical settings. Methods: A reliability and diagnostic accuracy study was conducted using 32 clinical vignettes based on the literature and pre-existing clinical data. The vignettes represented patients with and without the characteristics of nociplastic pain and were reviewed independently by two expert physiotherapists. Inter-rater and intra-rater reliability were evaluated with a 1-month interval between assessments. Criterion validity was analyzed by comparing the IASP criteria against the standardized vignettes as the reference standard. Sensitivity, specificity, and predictive values were calculated to assess diagnostic accuracy. Results: The IASP criteria demonstrated moderate-to-perfect intra-rater agreement (κ = 0.71-1.00, p < 0.05) and weak-to-perfect inter-rater agreement (κ = 0.52-1.00, p < 0.05). Criterion validity was moderate (κ = 0.68), with strong specificity (89.0%) and moderate sensitivity (69.0%). Positive and negative predictive values were high at 81.8% and 81.0%, respectively, supporting the criteria's accuracy in identifying and excluding nociplastic pain. Conclusions: The IASP criteria for nociplastic pain exhibited satisfactory reliability and criterion validity in this preliminary study, particularly after initial rater familiarization. Future research should evaluate their application in real-world clinical settings, explore concurrent and prognostic validity, and involve a broader range of raters to enhance generalizability.

The multidisciplinary team in the management of chronic pain and pain-related fear: an evidence-based approach in a clinical case

PURPOSE

Pain is a complex, intimate, and subjective experience influenced by biological, psychological, and social factors. This case report investigates the effectiveness of a multidisciplinary team approach in addressing chronic pain and pain-related fear.

CASE DESCRIPTION

The case report describes a 22-year-old female who experienced anterior knee pain for seven years, despite undergoing two knee surgeries and physiotherapy without improvement. Following a comprehensive assessment, which included a detailed medical history, clinical examination, and thoughtful clinical analysis, a multidisciplinary approach was recommended. Employing an evidence-based methodology that integrated neurocognitive rehabilitation techniques, including Pain Neuroscience Education, Graded Motor Imagery, and Tactile Discrimination Training, alongside psychological rehabilitation strategies such as Mindfulness, Acceptance and Commitment Therapy, and Problem-Solving Therapy, the report presents a comprehensive in-depth rehabilitation plan exemplifying the application of this multimodal approach within a clinical setting in a patient with chronic pain. This approach is designed not to address the biomechanical aspects but to delve into the cognitive facets associated with pain perception and avoidance, as well as potential psychological factors that may be influencing the onset and persistence of symptoms.

OUTCOMES

The scores from the rating scales provided valuable insights into patient progress in pain management, functional improvement, fear of movement, and overall physical, psychological, and emotional well-being, at six months.

CONCLUSION

This case report offers valuable insights into the usefulness of this multidisciplinary and multimodal approach, highlighting its potential as an avenue in the management of chronic pain and pain-related fear.

Application of the grading system for "nociplastic pain" in chronic primary and chronic secondary pain conditions: a field study

ABSTRACT

The concept "nociplastic pain" has been developed for patients with features of nociceptive system sensitization that are not explained as nociceptive or neuropathic. Here, we tested how well the recently published grading system differentiates between chronic primary and secondary pain conditions. We recruited patients with fibromyalgia (FMS, n = 41), complex regional pain syndrome (CRPS, n = 11), osteoarthritis (OA, n = 21), or peripheral nerve injury (PNI, n = 8). We used clinical history, pain drawings, quantitative sensory testing (QST), and questionnaires to classify their pains as possibly or probably "nociplastic." All patients with chronic primary pain exhibited widespread/regional pain not explainable by either nociceptive or neuropathic mechanisms. Widespread pain occurred in 12 patients with OA but was identified as nociceptive in 11 of 12. Regional pain occurred in 4 patients with PNI but was identified as neuropathic in 3 of 4. At this step, the grading system had 100% sensitivity and 93% specificity. Clinical evidence for pain hypersensitivity by QST, and history of hypersensitivity and mental comorbidities did not differentiate between chronic primary pain (QST: 36/52 = 69%, history: 43/52 = 83%) and secondary pain conditions (QST: 20/29 = 69%, history: 24/29 83%). Based on these data, specificity remained excellent (93%), but sensitivity dropped substantially (60%) due to lacking evidence for pain hypersensitivity in many patients with FMS. This low sensitivity suggests that the published grading system is not suitable for screening purposes. We suggest structural and content modifications to improve sensitivity, including placement of patient history before clinical examination and addition of a high tender point count as evidence for widespread pain hypersensitivity.

Enhancing pediatric pain management in Turkey: A modified Delphi study on culturally adapted pain neuroscience education for chronic pain in children

BACKGROUND

Pain Neuroscience Education (PNE) is a commonly used technique applied by physical therapists in the rehabilitation of chronic pain.

OBJECTIVE

The aim of this study was to culturally adapt an existing PNE for children with chronic pain (PNE4Kids) to Turkish children with chronic pain (PNE4Kids-Turkish).

METHODS

A three-round modified Delphi-study was conducted between September 2023 and February 2024. Experts completed questionnaire with 5 items to elicit demographic data and 16 closed and 7 open-ended questions to assess relevance of information, feasibility of stories, visual information, and clarity of message in the 4 main areas of 'normal pain biology', 'pain modulation', 'chronic pain, adaptations, central sensitization', and 'the application and implications of PNE4Kids. MAXQDA software was used for qualitative analysis of open-ended questions. A total of 38 experts (mean age: 36.6 ± 9.05 years, 6 male, 32 female) were recruited for this study.

RESULTS

The results of the first round indicated that 84-100 % of Delphi experts strongly agreed or agreed on the relevance of information, feasibility of stories, visual information, and clarity of message in respect of the 4 main areas. During second and third round, an acceptable degree of agreement with clinical usefulness of PNE4Kids-Turkish materials was obtained.

CONCLUSIONS

PNE4Kids was culturally adapted for Turkish children suffering from chronic pain. The findings of this study mainly highlight the viewpoints of the experts.

IMPLICATION TO PRACTICE

This is the first study to have developed and culturally adapted the PNE4Kids for Turkish children with chronic pain. The PNE4Kids-Turkish is crucial, valuable, helpful, and understandable for Turkish children with chronic pain. In addition, the PNE4Kids-Turkish has the potential to close the gap in research and clinical areas for Turkish children with chronic pain.

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.

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

Background

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

Objective

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

Design

Cross-sectional.

Methods

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

Results

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

Conclusion

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

'I presumed the pain would eventually get better by itself'; challenges with access to rehabilitation for upper limb dysfunction after breast cancer treatment - Descriptive and qualitative findings from a cross-sectional survey

PURPOSE

Sixty percent of breast cancer patients develop persistent upper limb pain and dysfunction, but only limited knowledge exists about how these symptoms relate to rehabilitation access.

METHODS

A postal survey was sent to patients treated at a London University Teaching Hospital (2018-2020). Data were collected on pain (Pain Detect), shoulder function (Disability of Shoulder Arm and Hand (DASH)), quality-of-life (QoL) (EQ-5D-5L), and clinical characteristics, including treatment and access to rehabilitation. The free-text section invited patients' comments on upper limb symptoms and management strategies, which were analysed thematically. Quantitative data were analysed descriptively, and the medians were examined with Mann-Whitley U-Tests or Kruskal-Wallis Test.

RESULTS

Of 511 patients surveyed, 162 (32 %) questionnaires were returned and analysed. Respondents' mean age was 62 years (SD 11.3). The majority had Sentinel Node Biopsy 71 % (116/162) and mastectomy 61 % (99/162). 73 % (119/162) reported pain. Mean (SD) Pain Detect and DASH Score were respectively 11.07 (7) and 21.7 (21.5), with 51 % recording significant shoulder dysfunction, and only 28 % reporting access to rehabilitation. Individuals with neuropathic pain had significantly higher median (range) DASH score 60.8 (35.8, 75.0) p = 0.000. Median DASH score for sedentary individuals was significantly higher 22.9 (7.9, 31.8) p = 0.0009. Free-text analysis revealed persistent, progressive symptoms, mixed attitudes towards exercise and variations in access to rehabilitation and support.

CONCLUSION

Two years following surgery many patients reported significant upper limb symptoms which adversely impact on QoL. However, approximately two thirds did not access potentially beneficial rehabilitation treatments. There is a need to improve pathways of care.

Understanding inter-individual variability of experimental pain habituation and conditioned pain modulation in healthy individuals

Although reduced experimental pain habituation is proposed as a proxy of diminished endogenous pain modulatory capacity in chronic pain, prior studies show contradictory findings. Even across healthy participants, pain habituation varies substantially, which may relate to another measure of endogenous pain modulation, i.e., conditioned pain modulation (CPM). Hence, this study investigated the relationship between pain habituation and CPM. Pain habituation was assessed in 45 healthy participants between two blocks of 15-20 contact-heat stimuli applied to the hand. Habituation of subjective pain ratings and objective neurophysiological readouts (contact-heat evoked potential (CHEP) and palmar sympathetic skin response (SSR)) was investigated. CPM was assessed by comparing heat pain thresholds before and after hand immersion in a noxious cold (9 °C) and lukewarm water bath (32 °C, to control for repeated measures effects). Pain habituation showed a large variability, with subjective but not objective pain habituation correlating with cold-induced CPM effects (r = 0.50; p = 0.025). This correlation was not observed for 'true' CPM effects (corrected for repeated measures effects) nor for CPM effects induced by a lukewarm water bath. These findings suggest that the observed variability in subjective pain habituation may be influenced by both descending endogenous pain modulation and peripheral adaptation processes associated with repeated measures. Objective pain habituation readouts, i.e., CHEPs and SSRs, capture different, complementary aspects of endogenous pain modulation.

Neuropathic pain is a feature in patients with symptomatic femoral acetabular impingement

Femoral acetabular impingement syndrome (FAIS) is a cause of hip pain thought to be nociceptive, although pain phenotypes e.g., burning, pain attacks, prickling, numbness etc., are reported, mimicking neuropathic pain. Although no lesion to the somatosensory system is identified, neuropathic pain (NeP) may explain why nociceptive-focussed treatments are not always successful.

OBJECTIVE

To identify NeP in patients with FAIS and investigate if related to poorer outcomes.

DESIGN

A secondary analysis of the Femoral Acetabular Impingement Trial (FAIT). Outcome of interest: PainDETECT questionnaire; secondary outcomes of interest; International Hip Outcome Tool (iHOT33), Hospital Anxiety and Depression Scale (HADS) and VAS 'average pain over a month', at baseline and 8 months follow-up. Intervention (surgery or physiotherapy) were pooled.

RESULTS

173 data sets at baseline; 123 at 8 months follow-up. Baseline painDETECT identified three groups: 69% nociceptive, 19% unclear and 12% neuropathic pain phenotypes. Baseline, median scores were higher for the neuropathic group compared to the nociceptive group demonstrating borderline anxiety (9.5(5.3 to 14.2), 5(3 to 8), higher normal values for depression (7.5(2.3 to 11.8), (4(2 to 9), higher average pain (7 (6 to 8), 5(4 to 6) and lower iHOT33 14.2(9 to 21.1), 38.4(26.2 to 55.7). Post treatment, there was a median change in the neuropathic score in both iHOT33 (40.8 (25 to 76.5) with a median difference of 24.13 (CI 95% 10.46 to 45.92) and average pain 4.5(1.5 to 7) with a median difference of 2 (CI 95% 1 to 5) but to a lesser amount than the nociceptive group, iHOT33 (64(38.2 to 86.6) with a median difference of 15.50 (CI 95% 6.41 to 21.82) and average pain 3(1 to 5.7) with a median difference of 1 (CI 95% 0.5 to 1).

CONCLUSION

NeP exists in symptomatic FAIS patients and is associated with increased average pain, and functional limitations. Nociceptive-targeted treatment improves hip function and pain but with less improvement in the NeP group when compared to the nociceptive group. Pain phenotyping before intervention may improve outcomes. CONTRIBUTION OF PAPER.

Pain neuroscience education and motor imagery-based exercise protocol for patients with fibromyalgia: A randomized controlled trial

BACKGROUND

This study is a randomized controlled, biopsychosocial study investigating the effectiveness of pain neuroscience education (PNE) and motor imagery-based exercise protocol (MIEP) on fibromyalgia pain.

METHODS

Our study has four groups (MIEP n = 12, PNE n = 12, MIEP + PNE n = 14, Control n = 12) and all participants (n = 50) consist of patients diagnosed with fibromyalgia with chronic back pain. The primary outcome measure was pain intensity, and secondary outcome measures were beliefs, kinesiophobia, anxiety-depression, cognitive-mood, self-esteem, and body awareness.

RESULTS

A statistically significant decrease in pain intensity was observed in all experimental groups, without any group being superior (Visual Analog Scale [VAS]: MIEP + PNE p = .003, 95% confidence interval [CI], -4.7078 to -0.9922; MIEP p = .003, 95% CI, -5.4806 to -1.0194; PNE p = .002, 95% CI, -3.6139 to -1.5461). There was a significant improvement in organic beliefs in both groups where PNE was applied (MIEP + PNE: p = .017, 95% CI, -7.8211 to -0.3189; PNE: p = .003, 95% CI, -9.7999 to -0.0401). A significant superiority in organic pain beliefs was detected in the MIEP + PNE group compared to the control group (p = .008, 95% CI, 1.7241-9.4959).

CONCLUSIONS

According to this study, in which MIEP and PNE were combined, there was a decrease in pain intensity when both applications were applied together and when they were applied one by one. MIEP has improved her motor imagery ability, improved pain and increased body awareness. PNE has improved people's organic pain beliefs; removed people from fears, catastrophizing, and negative thoughts about pain; improved easier management of psychological processes and cognitive-emotion regulation ability.

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.

Indication for spinal sensitization in chronic low back pain: mechanical hyperalgesia adjacent to but not within the most painful body area

Introduction

In 85% of patients with chronic low back pain (CLBP), no specific pathoanatomical cause can be identified. Besides primary peripheral drivers within the lower back, spinal or supraspinal sensitization processes might contribute to the patients' pain.

Objectives

The present study conceptualized the most painful area (MP) of patients with nonspecific CLBP as primarily affected area and assessed signs of peripheral, spinal, and supraspinal sensitization using quantitative sensory testing (QST) in MP, a pain-free area adjacent to MP (AD), and a remote, pain-free control area (CON).

Methods

Fifty-nine patients with CLBP (51 years, SD = 16.6, 22 female patients) and 35 pain-free control participants individually matched for age, sex, and testing areas (49 years, SD = 17.5, 19 female participants) underwent a full QST protocol in MP and a reduced QST protocol assessing sensory gain in AD and CON. Quantitative sensory testing measures, except paradoxical heat sensations and dynamic mechanical allodynia (DMA), were Z-transformed to the matched control participants and tested for significance using Z-tests (α = 0.001). Paradoxical heat sensations and DMA occurrence were compared between cohorts using Fisher's exact tests (α = 0.05). The same analyses were performed with a high-pain and a low-pain CLBP subsample (50% quantile).

Results

Patients showed cold and vibration hypoesthesia in MP (all Ps < 0.001) and mechanical hyperalgesia (P < 0.001) and more frequent DMA (P = 0.044) in AD. The results were mainly driven by the high-pain CLBP subsample. In CON, no sensory alterations were observed.

Conclusion

Mechanical hyperalgesia and DMA adjacent to but not within MP, the supposedly primarily affected area, might reflect secondary hyperalgesia originating from spinal sensitization in patients with CLBP.

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

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

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.

Pre-operative pain pressure threshold association with patient satisfaction following Total Knee Arthroplasty

Background

Total knee arthroplasty (TKA) is commonly performed for the treatment of knee osteoarthritis (KOA). Poor satisfaction continues to be seen after TKA. Whilst reasons for poor patient satisfaction are multifactorial, there is a strong correlation with persistent pain following TKA. Studies have shown an association between local and remote mechanical hypersensitivity, measured using pressure pain thresholds (PPTs), and severity of knee osteoarthritis and functional status. We aimed to determine if the pre-operative PPTs were associated with patient satisfaction following TKA.

Methods

A prospective longitudinal study of 77 individuals was undertaken. Regression modelling assessed the relationship between Patient Satisfaction using the Knee Society Score (satisfaction subscale) following TKA for KOA, and PPTs recorded pre-operatively locally and remote to the affected knee, while accounting for potentially confounding patient demographic and psychosocial factors.

Results

Lower PPTs (indicating increased mechanical hypersensitivity) locally and remote to the operative knee were modestly associated with lower patient satisfaction in the short-term (six weeks) following TKA (β 0.25-0.28, adjR2 = 0.14-0.15), independent of demographic or psychosocial influences. However, this relationship progressively diminished in the intermediate and long-term post TKA.

Conclusion

While pre-operative PPT measures may provide some foresight to patient satisfaction post TKA in the short term, these measures appear to provide little insight to patient satisfaction in the intermediate and longer term.

Effects of pain education on disability, pain, quality of life, and self-efficacy in chronic low back pain: A randomized controlled trial

BACKGROUND

Low back pain stands as a prevalent contributor to pain-related disability on a global scale. In addressing chronic low back pain (CLBP), there is a growing emphasis on incorporating psychological strategies into the management process. Among these, pain education interventions strive to reshape pain beliefs and mitigate the perceived threat of pain. This randomized controlled trial sought to assess the effects of pain education on various aspects, including pain levels, disability, quality of life, self-efficacy, and prognostic characteristics in individuals grappling with CLBP.

METHODS

The clinical trial, retrospectively registered with the Clinical Trials Registry of India (CTRI/2021/08/035963), employed a two-arm parallel randomized design. Ninety-two participants with CLBP were randomly assigned to either the standard physiotherapy care with a pain education program or the control group. Both groups underwent a 6-week intervention. Assessment of pain intensity (using NPRS), disability (using RMDQ), self-efficacy (using the general self-efficacy scale), and well-being (using WHO 5I) occurred both before and after the 6-week study intervention.

FINDINGS

Post-intervention score comparisons between the groups revealed that the pain education intervention led to a significant reduction in disability compared to the usual standard care at 6 weeks (mean difference 8.2, p < 0.001, effect size Cohen d = 0.75), a decrease in pain intensity (mean difference 3.5, p < 0.001, effect size Cohen d = 0.82), and an improvement in the well-being index (mean difference 13.7, p < 0.001, effect size Cohen d = 0.58).

CONCLUSION

The findings suggest that integrating a pain education program enhances the therapeutic benefits of standard physiotherapy care for individuals dealing with chronic LBP. In conclusion, the clinical benefits of pain education become apparent when delivered in conjunction with standard care physiotherapy during the management of chronic low back pain.

The effect of joint position sense therapy on chronic shoulder pain with central sensitization

BACKGROUND

Chronic shoulder pain is a common musculoskeletal problem associated with unreleased pain and functional dysfunction that can evolve into central sensitization. Some forms of manual therapy may exacerbate pain and central sensitization. This study investigated the impact of joint position sense therapy (JPST), a moderate joint proprioception training technique, on central sensitization, shoulder functional dysfunction, and pain in patients with chronic shoulder pain compared with more intense exercises or aggressive manual therapies.

METHODS

We assessed the pressure pain threshold (PPT) in 30 patients with and 30 patients without chronic shoulder pain. The assessment focused on 4 muscle sites: deltoid, upper trapezius, brachioradialis, and tibialis anterior. Thirty patients with chronic shoulder pain were randomly divided into the JPST and control groups. The JPST group underwent additional shoulder joint position-sense training. The efficiency outcomes were the disabilities of the arm, shoulder, and hand questionnaire, visual analog scale (VAS), and PPT, evaluated at baseline and after the intervention.

RESULTS

Significant differences were observed in the PPT values at the brachioradialis (P < .05), deltoid (P < .01), and trapezius (P < .001) among the non-chronic and chronic groups, but not in the tibialis anterior muscle (P > .05). Although both control and JPST interventions effectively improved the disabilities of the arm, shoulder, and hand questionnaire score, pain intensity, and PPT values in the upper limb, the outcomes in the JPST group were significantly different from those in the control group.

CONCLUSIONS

Generalized hyperalgesia changes limited to the upper limbs were observed in patients with chronic shoulder pain. JPST has beneficial effects on pain control and functional dysfunction in patients with chronic shoulder pain.

Knowledge on cause, clinical manifestation and treatment for fibromyalgia among medical doctors: A worldwide survey

OBJECTIVES

Hench introduced the fibromyalgia syndrome almost 50 years ago. In the meantime, the prevalence has increased, the clinical criteria have changed and the way we explain (chronic) pain has altered.

DESIGN

In the current study, we conducted a worldwide survey in which we investigate whether medical doctors are familiar with the American College of Rheumatology (ACR) criteria for fibromyalgia and, if so, whether these medical doctors adhere to the clinical guidelines following evidence-based treatments.

RESULTS

In total, 286 medical doctors from 43 countries spread over 6 continents filled out the survey. In most of the countries, the diagnosis fibromyalgia was used. Only 10% adhere to the ACR criteria, widespread pain (44%), unrefreshed sleep (24%), fatigue (20%) and cognitive problems (8%) were most used diagnostic criteria. Of the respondents, 94 (32%) mentioned that the cause is unknown or idiopathic, but also a wide variety of other causes was mentioned. More than 70 different treatment options were provided, of which 24% of the responses were classified as according to the clinical guidelines. From this study, we conclude that many medical doctors do not follow the ACR criteria; the majority has an inappropriate knowledge of causes for fibromyalgia and that a minority of treatment advice adhere to the guidelines.

Amyotrophic Lateral Sclerosis and Pain: A Narrative Review from Pain Assessment to Therapy

Amyotrophic lateral sclerosis (ALS) is the most frequent neurodegenerative disease of the motor system that affects upper and lower motor neurons, leading to progressive muscle weakness, spasticity, atrophy, and respiratory failure, with a life expectancy of 2-5 years after symptom onset. In addition to motor symptoms, patients with ALS have a multitude of nonmotor symptoms; in fact, it is currently considered a multisystem disease. The purpose of our narrative review is to evaluate the different types of pain, the correlation between pain and the disease's stages, the pain assessment tools in ALS patients, and the available therapies focusing above all on the benefits of cannabis use. Pain is an underestimated and undertreated symptom that, in the last few years, has received more attention from research because it has a strong impact on the quality of life of these patients. The prevalence of pain is between 15% and 85% of ALS patients, and the studies on the type and intensity of pain are controversial. The absence of pain assessment tools validated in the ALS population and the dissimilar study designs influence the knowledge of ALS pain and consequently the pharmacological therapy. Several studies suggest that ALS is associated with changes in the endocannabinoid system, and the use of cannabis could slow the disease progression due to its neuroprotective action and act on pain, spasticity, cramps, sialorrhea, and depression. Our research has shown high patients' satisfaction with the use of cannabis for the treatment of spasticity and related pain. However, especially due to the ethical problems and the lack of interest of pharmaceutical companies, further studies are needed to ensure the most appropriate care for ALS patients.

Application of a Clinical Approach to Diagnosing Primary Pain: Prevalence and Correlates of Primary Back and Neck Pain in a Community Physiatry Clinic

Chronic back or neck pain (CBNP) can be primary (nociplastic or neuroplastic; without clear peripheral etiology) or secondary (to nociceptive or neuropathic causes). Expanding on available models of nociplastic pain, we developed a clinic-ready approach to diagnose primary/nociplastic pain: first, a standard physical exam and review of imaging to rule out secondary pain; and second, a detailed history of symptom presentation to rule in primary pain. We trained a physician who evaluated 222 patients (73.9% female, age M = 59.6) with CBNP; patients separately completed pain and psychosocial questionnaires. We estimated the prevalence of primary CBNP and explored biomedical, imaging, and psychological correlates of primary CBNP. Although almost all patients (97.7%) had at least 1 spinal anomaly on imaging, the diagnostic approach estimated that 88.3% of patients had primary pain, 5.0% had secondary pain, and 6.8% had mixed pain. Patients with primary pain were more likely than the other 2 groups of patients (combined as "non-primary pain") to report certain functional conditions, central sensitization, and features such as sensitivity to light touch, spreading pain, and pain worsening with stress; however, no difference was detected in depression, anxiety, and pain catastrophizing between those with primary and nonprimary pain. These findings are consistent with prior estimates that 85 to 90% of CBNP is "nonspecific." Further research is needed to validate and perhaps refine this diagnostic approach, which holds the potential for better outcomes if patients are offered treatments targeted to primary pain, such as pain neuroscience education and several emerging psychological therapies. PERSPECTIVE: We developed an approach to diagnose chronic primary pain, which was applied in a physiatry clinic to 222 patients with CBNP. Most patients (88.3%) had primary pain, despite almost universal anomalies on spinal imaging. This diagnostic approach can guide educational and psychological treatments tailored for primary pain.

The Effect of Central Sensitization on Postoperative Neurocognitive Dysfunction in Hospitalized Elderly Patients: A Prospective Cohort Clinical Trial

OBJECTIVE

To investigate whether central sensitization (CS) in elderly patients was a predictive risk factor for postoperative neurocognitive dysfunction (PNCD).

METHODS

One hundred and thirty-three aged patients undergoing total knee arthroplasty (TKA) who received femoral nerve block and general anesthesia were recruited in this research and prospectively assigned into two groups according to the Central Sensitization Inventory (CSI) score: group C (n = 106, CSI score less than 40) and group CS (n = 27, CSI score higher than 40). Scores of Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), Confusion Assessment Method (CAM), Numerical Rating Scale (NRS) and Quality of recovery-40 (QoR-40) questionnaires were assessed. Basic information and clinical records of all participants were also collected.

RESULTS

PNCD occurred in 24 (22.6%) of patients in group C and 16 (59.3%) in group CS (p < .05). Multivariate logistic regression analysis revealed that patients with CSI score ≥40 before surgery exhibited higher risk of PNCD after adjustment for other risk factors (p < .05). Compared to group C, the pre- and post-operative NRS scores, pain duration, the WOMAC score, and propofol consumptions for anesthesia induction were significantly increased in group CS (p < .05).

CONCLUSION

Hospitalized elderly patients with clinical symptoms of CS scores may have increased risk of PNCD following TKA.

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.

Characterizing clinical progression in patients with musculoskeletal pain by pain severity and central sensitization-related symptoms

Central sensitization-related symptoms (CSS) are associated with the severity and progression of pain. The relationship between the severity of pain/CSS and clinical progresses remains unclear. This multicenter, collaborative, longitudinal study aimed to characterize the clinical outcomes of patients with musculoskeletal pain by classifying subgroups based on the severity of pain/CSS and examining changes in subgroups over time. We measured the pain intensity, CSS, catastrophic thinking, and body perception disturbance in 435 patients with musculoskeletal pain. Reevaluation of patients after one month included 166 patients for pain intensity outcome and 110 for both pain intensity and CSS outcome analysis. We classified the patients into four groups (mild pain/CSS, severe pain/mild CSS, severe pain/CSS, and mild pain/severe CSS groups) and performed multiple comparison analyses to reveal the differences between the CSS severity groups. Additionally, we performed the adjusted residual chi-square to identify the number of patients with pain improvement, group transition, changing pain, and CSS pattern groups at baseline. The most characteristic result was that the mild and severe CSS groups showed worsening pain. Moreover, many of the group transitions were to the same group, with a few transitioning to a group with mild pain/CSS. Our findings suggest that the severity and improvement of CSS influence pain prognosis.

PaiNEd app. Assessing central sensitization in survivors of breast cancer: A reliability study

Introduction

Pain is a common adverse event in survivors of breast cancer (sBCs). As there is no gold standard to assess pain experience predominantly related to central sensitization (CS) symptoms, we designed the PaiNEd app, which includes an algorithm to report whether patients are under predominant CS pain mechanisms.

Objective

We aimed to assess the reliability of the PaiNEd app to estimate whether sBC pain experience is predominantly related to CS symptoms.

Methods

An observational, descriptive reliability design was employed to assess the inter- and intrarater reliability of the PaiNEd app. This app includes an algorithm that considers the number of painful body parts and some questionnaires related to pain, such as the Numeric Pain-Rating Scale, the Brief Pain Inventory, the Tampa Scale for Kinesiophobia, the Pain Catastrophizing Scale, and the Central Sensitization Inventory (CSI).

Results

A total of 21 sBCs with persistent pain were recruited. We observe a general trend of close agreement between the paper-based and app-based formats (ICCs ranged between 0.802 and 0.972; Cronbach's alpha ranged between 0.797 and 0.971). Test-retest reliabilities were moderate to excellent (ICCs ranged between 0.510 and 0.941; Cronbach's alpha ranged between 0.499 and 0.938). The agreement between the categorization of the CS algorithm and the CSI (cut-off point ≥ 40 for CS symptoms) was 95.24%.

Conclusion

The PaiNEd app emerges as a robust tool for evaluating pain experience predominantly related to CS and pain-related symptoms in sBCs. Its demonstrated reliability not only bolsters its utility but also signifies its potential as a valuable asset for healthcare professionals engaged in pain education programs.

Central sensitization negatively influences the level of disability in female patients with anterior knee pain

PURPOSE

To define the prevalence of Central Sensitization (CS) in patients with Anterior Knee Pain (AKP) and determine whether there is an association between CS and the magnitude of pain, disability, quality-of-life and psychological impairment.

METHODS

The data of a total of 44 AKP female patients with a mean age of 27.7 years (15-50) recruited consecutively from hospital outpatient knee clinics were prospectively included in this study. The patients had no antecedents of knee trauma or surgery and no history of injury or disease of the nervous system. There were also 50 healthy female controls with a mean age of 26.1 years (16-46). CS was evaluated using the Central Sensitization Inventory (CSI). Quality-of-life was evaluated using the EuroQoL-5D questionnaire. Self-reporting of clinical pain intensity was obtained using the Visual Analogue Scale. The Kujala Knee Scale and IKDC form were used to evaluate disability. Anxiety and depression were evaluated using the Hospital Anxiety and Depression Subscale (HAD). Kinesiophobia was measured with the Tampa Scale for Kinesiophobia (TSK-11) and catastrophizing by means of the Pain Catastrophizing Scale (PCS).

RESULTS

Sixteen AKP patients (36%), and 2 (4%) of the healthy controls presented with central sensitization (p < 0.01). AKP patients with CS have a greater degree of disability based on the Kujala Scale and higher levels of anxiety and depression than AKP patients without CS. The score of AKP patients in the CSI correlated weakly with disability and quality of life and moderately with anxiety and depression. However, no association was seen between CSI score and pain intensity, nor with catastrophizing and kinesiophobia. A multivariate logistic regression analysis showed that only depression was statistically significant in the prediction of the presence of CS (odds ratio 1.45; 95% CI 1.07 to 1.96).

CONCLUSIONS

AKP patients have a significantly higher prevalence of CS in comparison with what has been reported for the general population. This finding suggests the presence of altered pain modulation in a subgroup of AKP patients.

LEVEL OF EVIDENCE

Level III.

Thermal Grill Illusion in Post-Stroke Patients: Analysis of Clinical Features and Lesion Areas

Purpose

In the thermal grill illusion, participants experience a feeling similar to burning pain. The illusion is induced by simultaneously touching warm and cool stimuli in alternating positions. In post-stroke pain, central sensitization is caused by a variety of factors, including damage to the spinothalamic tract and shoulder pain. Because the thermal grill illusion depends on central mechanisms, it has recently been suggested that it may be a useful indicator of central sensitization. Therefore, we hypothesized that post-stroke patients who are more likely to experience central sensitization may also be more likely to experience a thermal grill sensation of pain and discomfort than the likelihood among those who are less likely to experience central sensitization. However, the effects of the thermal grill illusion in post-stroke patients have not yet been reported. In this pilot study, we conducted the thermal grill illusion procedure in post-stroke patients and analyzed the relationship between clinical somatosensory functions and thermal grill sensations. We also conducted brain imaging analysis to identify brain lesion areas that were associated with thermal grill sensations.

Patients and Methods

Twenty patients (65.7 ± 11.9 years old) with post-stroke patients participated in this study. The thermal grill illusion procedure was performed as follows: patients simultaneously touched eight water-filled copper bars, with the water temperature adjusted to provide alternate warm (40°C) and cold (20°C) stimuli.

Results

Thermal grill sensation of pain and discomfort tended to be associated with the wind-up phenomenon in bedside quantitative sensory testing and thermal grill sensation of discomfort was also related to damage to the thalamic lateral nucleus.

Conclusion

These findings suggest that the thermal grill illusion might measure central sensitization, and that secondary brain hyperactivity might lead to increased thermal grill sensations.

Precision management of post-COVID pain: An evidence and clinical-based approach

Background Pain after a SARS-CoV-2 acute infection (post-COVID pain) is becoming a new healthcare emergency but remains underestimated and most likely undertreated due to a lack of recognition of the phenomenon and knowledge of the underlying pain mechanisms. Evidence supporting any particular treatment approach for the management of post-COVID pain is lacking. Large variability in the patient response to any standard pain treatments is clinically observed, which has led to calls for a personalized, tailored approach to treating patients with chronic post-COVID pain (i.e. 'precision pain medicine'). Applying the global concerted action towards precision medicine to post-COVID pain could help guide clinical decision-making and aid in more effective treatments. Methods The current position paper discusses factors to be considered by clinicians for managing post-COVID pain ranging from identification of the pain phenotype to genetic consideration. Results The ability of clinicians to phenotype post-COVID pain into nociceptive, neuropathic, nociplastic or mixed type is suggested as the first step to better planification of a treatment programme. Further, the consideration of other factors, such as gender, comorbidities, treatments received at the acute phase of infection for onset-associated COVID-19 symptoms, factors during hospitalization or the presence of emotional disturbances should be implemented into a treatment programme. Conclusions Accordingly, considering these factors, management of post-COVID pain should include multimodal pharmacological and non-pharmacological modalities targeting emotional/cognitive aspects (i.e. psychological and/or coping strategies), central sensitization-associated mechanisms (i.e. pain neuroscience education), exercise programmes as well as lifestyle interventions (e.g. nutritional support and sleep management). SIGNIFICANCE: This position paper presents an evidence-based clinical reasoning approach for precision management of post-COVID pain.

Identifying chronic low back pain phenotypic domains and characteristics accounting for individual variation: a systematic review

ABSTRACT

Interpatient variability is frequently observed among individuals with chronic low back pain (cLBP). This review aimed at identifying phenotypic domains and characteristics that account for interpatient variability in cLBP. We searched MEDLINE ALL (through Ovid), Embase Classic and EMBASE (through Ovid), Scopus, and CINAHL Complete (through EBSCOhost) databases. Studies that aimed to identify or predict cLBP different phenotypes were included. We excluded studies that focused on specific treatments. The methodological quality was assessed using an adaptation of the Downs and Black tool. Forty-three studies were included. Although the patient and pain-related characteristics used to identify phenotypes varied considerably across studies, the following were among the most identified phenotypic domains and characteristics that account for interpatient variability in cLBP: pain-related characteristics (including location, severity, qualities, and duration) and pain impact (including disability, sleep, and fatigue), psychological domains (including anxiety and depression), behavioral domains (including coping, somatization, fear avoidance, and catastrophizing), social domains (including employment and social support), and sensory profiling (including pain sensitivity and sensitization). Despite these findings, our review showed that the evidence on pain phenotyping still requires further investigation. The assessment of the methodological quality revealed several limitations. We recommend adopting a standard methodology to enhance the generalizability of the results and the implementation of a comprehensive and feasible assessment framework to facilitate personalized treatments in clinical settings.

Individual endogenous pain modulation profiles within a multidimensional context of people with cervicogenic headache - A retrospective exploratory study

BACKGROUND

One in four individuals with cervicogenic headache (CeH) are unresponsive to therapy. Such therapy involves predominantly biomedical interventions targeting the upper-cervical spine. A recurring theme within musculoskeletal practice is the multidimensional nature and substantial heterogeneity of the condition. Such heterogeneity might be a reason for failure of a biomedical approach. Therefore, future studies investigating efficacy of managing CeH should ideally be based on identification, and better understanding of the heterogeneity of this population based on a comprehensive evaluation of clinically relevant contributing factors.

OBJECTIVES

The objective was to map profiles of individuals with CeH based on pain modulation within a multidimensional context.

DESIGN

Pain Modulation Profiles (PMPs) of 18 adults (29-51 years) with CeH were mapped retrospectively.

METHOD

The PMPs consisted of a Pain-Profile (bilateral suboccipital, erector spinae, anterior tibialis pressure pain thresholds), a Psycho-Social-Lifestyle-Profile (Depression, Anxiety, Stress Scale, Headache Impact test, Pittsburgh Sleep Quality Index), or a combination of both. Individual results were compared to normative data. Two Pain-Profiles were defined: normal or altered. Psycho-Social-Lifestyle-Profiles were categorized based on the number of altered psycho-social-lifestyle factors (range 0-5).

RESULTS

Mapping PMPs in individuals with CeH resulted in 50% presenting with a dominant altered Pain-Profile, 16.7% with a dominant altered Psycho-Social-Lifestyle-Profile, and 5.6% with dominant alterations in both Pain-Profile and Psycho-Social-Lifestyle-Profile.

CONCLUSION

Our results indicate heterogeneity of PMPs within the CeH population. Replication of these results is needed through dynamic assessment of the Pain-Profile before evaluating if these profiles can help patient-stratification.

Physiotherapy management of nociplastic pain: A Delphi study of Italian specialists

BACKGROUND AND PURPOSE

Nociplastic pain due to central sensitization (CS) is common in people suffering from chronic pain, but no clinical practice guideline is available in rehabilitative settings for patients' management. The aim of this study is to achieve expert consensus on physiotherapy competencies in the management of people with nociplastic pain and suspected CS mechanisms.

METHODS

A web-based Delphi process was employed. Experts in the rehabilitation field were recruited following pre-defined eligibility criteria. Following completion of three Delphi rounds, the final list of competencies was generated.

RESULTS

In all, 23 participants were recruited. They all completed Round 1 (23/23, 100%), twenty Round 2 and Round 3 (20/23, 87%). Following Round 1, seven areas were identified by the panel as crucial for CS physiotherapy management; 19 competencies out of 40 reached the consensus between experts, and nine additional competencies were added to Round 2 following literary review. Round 2 identified the agreement for all the 29 competencies. During Round 3, all the experts confirmed the final list generated through the consensus process.

DISCUSSION

An agreement between experts was found for the final list of competencies that a physiotherapist should implement every time it approaches people with suspected CS mechanisms. Further research is needed to support the clinical utility of our findings and their applicability in daily practice.

Assessment of Prevalence and Risk Factors for Central Sensitization Related to Shoulder Osteoarthritis and Rotator Cuff Tears Using the Central Sensitization Inventory: A Cross-Sectional Study in Shoulder Surgery Patients

Shoulder disorders occasionally cause intractable pain. Central sensitization (CS) may be involved in such pain. Identifying risk factors associated with CS is crucial for effective pain control. This study aimed to determine the effects of shoulder osteoarthritis and rotator cuff tears (RCT) on CS and associated factors. This study included patients evaluated for CS using the Central Sensitization Inventory (CSI) before surgery for shoulder osteoarthritis, RCT, or cuff tear arthropathy. Patients with a CSI score of 40 or higher were defined as having CS. The relationships between glenohumeral osteoarthritis (GHOA), RCT size, and CS were statistically analyzed. Multiple regression analysis was performed to examine the factors affecting CSI scores. Subjects included 167 patients: 131 patients had RCT without GHOA, 23 had GHOA with RCT, and 13 had GHOA without RCT. The GHOA group had a significantly higher CSI score (27.5 [10.8-40.5] vs. 18.0 [10.0-27.5]) and CS prevalence (27.8% vs. 8.4%) than the RCT without GHOA group. There was no significant correlation between RCT size and CSI scores. Multiple regression analysis showed that female sex, severe pain, and long pain duration were associated with higher CSI scores. Considering the risk factors for CS might be helpful in shoulder treatment.

Central sensitization in CRPS patients with widespread pain: a cross-sectional study

OBJECTIVE

Widespread pain hypersensitivity and enhanced temporal summation of pain (TSP) are commonly reported in patients with complex regional pain syndrome (CRPS) and discussed as proxies for central sensitization. This study aimed to directly relate such signs of neuronal hyperexcitability to the pain phenotype of CRPS patients.

METHODS

Twenty-one CRPS patients and 20 healthy controls (HC) were recruited. The pain phenotype including spatial pain extent (assessed in % body surface) and intensity were assessed and related to widespread pain hypersensitivity, TSP, and psychological factors. Quantitative sensory testing (QST) was performed in the affected, the contralateral and a remote (control) area.

RESULTS

CRPS patients showed decreased pressure pain thresholds in all tested areas (affected: t(34)  = 4.98, P < .001, contralateral: t(35) = 3.19, P = .005, control: t(31) = 2.65, P = .012). Additionally, patients showed increased TSP in the affected area (F(3,111) = 4.57, P = .009) compared to HC. TSP was even more enhanced in patients with a high compared to a low spatial pain extent (F(3,51) = 5.67, P = .008), suggesting pronounced spinal sensitization in patients with extended pain patterns. Furthermore, the spatial pain extent positively correlated with the Bath Body Perception Disturbance Scale (ρ = 0.491; P = .048).

CONCLUSIONS

Overall, we provide evidence that the pain phenotype in CRPS, that is, spatial pain extent, might be related to sensitization mechanism within the central nociceptive system. This study points towards central neuronal excitability as a potential therapeutic target in patients with more widespread CRPS.

[Nociplastic pain in research and practice : Overview of biopsychosocial principles, possibilities and difficulties]

Traditionally, two mechanistic pain categories were distinguished: nociceptive and neuropathic pain. After the definitions of these two mechanistic descriptors were refined more precisely in the International Association for the Study of Pain (IASP) taxonomy in 2011, a large group of patients remained whose pain could not be assigned to either of the two categories. Nociplastic pain was therefore proposed as a third mechanistic descriptor in 2016. This review article presents the current state of the integration of nociplastic pain into research and clinical practice. In particular, the possibilities and difficulties of applying this concept are addressed from a human and animal experimental research perspective.

Validity and reliability of the short form brief pain inventory in older adults with nociceptive, neuropathic and nociplastic pain

OBJECTIVE

The aim of this study was to evaluate the validity and reliability of the Short Form Brief Pain Inventory (SF-BPI) for community-dwelling Brazilian older adults with chronic neuropathic, nociceptive and nociplastic pain.

METHODS

Cross-sectional psychometric testing was conducted in a convenience sample, n=114 (66.5 ± 4.9 years).

RESULTS

The 2-factor structure of the SF-BPI was ratified by confirmatory factor analysis. Convergent validity was found between the SF-BPI and the Present Pain Intensity (PPI). There was good overall internal consistency (Cronbach's α: 0.87). Test-retest reliability was excellent for pain intensity and interference scores of the SF-BPI (ICC: 0.90 and 0.96, respectively), as well as inter-rater reliability for both dimensions (ICC: 0.77).

CONCLUSION

The findings support the validity and reliability of the SF-BPI for community-dwelling older adults with chronic pain and may contribute to health professionals having a brief multidimensional assessment for more effective therapeutic approaches in this population.

Test-retest reliability of pain extent and pain location using a novel pain drawing analysis software application, on patients with shoulder pain

OBJECTIVES

A method of pain assessment is the drawing of pain on a specially designed manikin where the patients color the area representing their pain distribution. In recent years, software applications have been developed for the purpose of digital pain drawing data acquisition and processing. Although such specific software applications have already been released, they have been built with obsolete programming tools. The purpose of the study was to investigate the test - retest reliability of a new pain drawing analysis software, in a sample of patients with shoulder pain.

METHODS

Data collected from 31 subjects with shoulder pain. Participants were asked twice to color their pain distribution in the painting environment of a tablet software application called 'Pain Distribution.'

RESULTS

The reliability of pain extent was found to be good (ICC = 0.80). The Jaccard index for the reliability of pain location was found to be moderate, equal to 42.02 ± 19.13%.

CONCLUSION

The results demonstrated good reliability of pain extent and moderate reliability of pain location using the new pain distribution analysis application 'Pain Distribution.' This pain drawing software application could be a reliable, inexpensive, and clinically usable solution for assessing the distribution of pain in patients with shoulder pain.

Between guidelines and clinical trials: evidence-based advice on the pharmacological management of non-specific chronic low back pain

The pharmacological management of nonspecific chronic low back pain (NCLBP) aims to restore patients' daily activities and improve their quality of life. The management of NCLBP is not well codified and extremely heterogeneous, and residual symptoms are common. Pharmacological management should be considered as co-adjuvant to non-pharmacological therapy, and should be guided by the symptoms reported by the patients. Depending on the individual severity of NCLPB, pharmacological management may range from nonopioid to opioid analgesics. It is important to identify patients with generalized sensory hypersensitivity, who may benefit from dedicated therapy. This article provides an evidence-based overview of the principles of pharmacological management of NCLPB.

Comparative effectiveness of TNF inhibitor vs IL-6 receptor inhibitor as monotherapy or combination therapy with methotrexate in biologic-experienced patients with rheumatoid arthritis: An analysis from the CorEvitas RA Registry

OBJECTIVE

Randomized controlled trials (RCTs) in biologic-naïve rheumatoid arthritis (RA) patients with high disease activity and inadequate response/intolerance to methotrexate have shown interleukin-6 (IL-6) receptor inhibitors (IL-6Ri) to be superior to tumor necrosis factor inhibitors (TNFi) as monotherapy. This observational study aimed to compare the effectiveness of TNFi vs IL-6Ri as mono- or combination therapy in biologic/targeted synthetic (b/ts) -experienced RA patients with moderate/high disease activity.

METHODS

Eligible b/ts-experienced patients from the CorEvitas RA registry were categorized as TNFi and IL-6Ri initiators, with subgroups initiating as mono- or combination therapy. Mixed-effects regression models evaluated the impact of treatment on Clinical Disease Activity Index (CDAI), patient-reported outcomes, and disproportionate pain (DP). Unadjusted and covariate-adjusted effects were reported.

RESULTS

Patients initiating IL-6Ri (n = 286) vs TNFi monotherapy (n = 737) were older, had a longer RA history and higher baseline CDAI, and were more likely to initiate as third-line therapy; IL-6Ri (n = 401) vs TNFi (n = 1315) combination therapy initiators had higher baseline CDAI and were more likely to initiate as third-line therapy. No significant differences were noted in the outcomes between TNFi and IL-6Ri initiators (as mono- or combination therapy).

CONCLUSION

This observational study showed no significant differences in outcomes among b/ts-experienced TNFi vs IL-6Ri initiators, as either mono- or combination therapy. These findings were in contrast with the previous RCTs in biologic-naïve patients and could be explained by the differences in the patient characteristics included in this study. Further studies are needed to help understand the reasons for this discrepancy in the real-world b/ts-experienced population.

Effect of Pain Neuroscience Education with Conventional Physiotherapy via Telerehabilitation on Pain Catastrophizing and Function in Patients with Osteoarthritis Knee: A Randomized Controlled Trial

Aim

By explaining to the patient the biological processes underneath their pain condition, pain neuroscience education (PNE) is a form of educational intervention that aims to relieve pain and impairment.

Materials and Methods

Patients with knee osteoarthritis (OA) referred to outpatient physiotherapy clinic in India during August 2021 to June 2022 were asked to participate. Out of the eligible patients, 35 were randomly assigned to PNE group and 35 to the control group. Self-reports of Pain Catastrophizing Scale (PCS), Patient Specific Function Scale (PSFS), and Numerical Pain Rating Scale (NPRS) were recorded at baseline (T1) and at 2 weeks (T2).

Results

After 2 weeks of follow-up, all the three outcome measures were found to be significant in the PNE group. The results of the unpaired t-test revealed statistically significant result posttest for PCS (mean difference 11.4) and NPRS (mean difference 1.20). There was no mean difference found in the patient function (PSFS) between groups.

Conclusion

The results suggest that adding a program of PNE to conventional physiotherapy exercises led to a greater reduction in pain catastrophization, patient-specific function, and pain intensity rather than conventional physiotherapy alone in patients with knee OA at 2 weeks' follow-up.

Healthcare Professionals’ Knowledge about Pediatric Chronic Pain: A Systematic Review

Pediatric chronic pain is a common public health problem with a high prevalence among children and adolescents. The aim of this study was to review the current knowledge of health professionals on pediatric chronic pain between 15–30% among children and adolescents. However, since this is an underdiagnosed condition, it is inadequately treated by health professionals. To this aim, a systematic review was carried out based on a search of the electronic literature databases (PubMed and Web of Science), resulting in 14 articles that met the inclusion criteria. The analysis of these articles seems to show a certain degree of heterogeneity in the surveyed professionals about the awareness of this concept, especially regarding its etiology, assessment, and management. In addition, the extent of knowledge of the health professionals seems to be insufficient regarding these aspects of pediatric chronic pain. Hence, the knowledge of the health professionals is unrelated to recent research that identifies central hyperexcitability as the primary factor affecting the onset, persistence, and management of pediatric chronic pain.

Myofascial Pain Syndrome: A Nociceptive Condition Comorbid with Neuropathic or Nociplastic Pain

Myofascial pain syndrome is featured by the presence of myofascial trigger points (TrPs). Whether TrPs are primary or secondary phenomena or if they relate to central or peripheral nervous system disorders is controversial. Referred pain, a cardinal sign of TrPs, is a central phenomenon driven by peripheral input. In 2021, the International Association for the Study of Pain (IASP) proposed a clinical criteria and grading system for classifying patients with pain on nociceptive, neuropathic, or nociplastic phenotypes. Myofascial TrP pain has been traditionally categorized as a nociceptive phenotype; however, increasing evidence supports that this condition could be present in patients with predominantly nociplastic pain, particularly when it is associated with an underlying medical condition. The clinical response of some therapeutic approaches for managing TrPs remains unclear. Accordingly, the ability to classify myofascial TrP pain into one of these phenotypes would likely be critical for producing more successful clinical treatment outcomes by a precision medicine approach. This consensus paper presents evidence supporting the possibility of subgrouping individuals with myofascial TrP pain into nociceptive, nociplastic, or mixed-type phenotype. It is concluded that myofascial pain caused by TrPs is primarily a nociceptive pain condition, is unlikely to be classified as neuropathic or nociplastic, but can be present in patients with predominantly neuropathic or nociplastic pain. In the latter cases, management of the predominant central pain problem should be a major treatment goal, but the peripheral drive from TrPs should not be ignored, since TrP treatment has been shown to reduce sensitization-associated symptomatology in nociplastic pain conditions, e.g., fibromyalgia.

A Potential Objective Sign of Central Sensitization: Referred Pain Elicited by Manual Gluteus Minimus Muscle Exploration is Coincident with Pathological Autonomic Response Provoked by Noxious Stimulation

Referred pain/sensation provoked by trigger points suits the nociplastic pain criteria. There is a debate over whether trigger points are related to a peripheral phenomenon or central sensitization (CS) processes. Referred pain is considered a possible sign of CS, which occurs probably mainly due to the abnormal activity of the immune and autonomic nervous systems. To confirm abnormal autonomic reactivity within the referred pain zone of active trigger points, a new diagnostic tool, the Skorupska Protocol® (the SP test®), was applied. The test uses noxious stimulation (10 minutes of dry needling under infrared camera control) as a diagnostic tool to confirm abnormal autonomic nervous system activity. A response to the SP test® of healthy subjects with referred pain sensations provoked by latent trigger points (LTrPs) stimulation was not explored before. The study aims at examining if LTrPs can develop an autonomic response. Methods. Two groups of healthy subjects, (i) gluteus minimus LTrPs with referred pain (n = 20) and (ii) control (n = 27), were examined using the SP test®. Results. Abnormal autonomic activity within the referred pain zone was confirmed for all analyzed LTrPs subjects. 70% of control subjects had no feature of vasodilatation and others presented minor vasomotor fluctuations. The size of vasomotor reactivity within the referred pain zone was LTrPs 11.1 + 10.96% vs. control 0.8 + 0.6% (p < 0.05). Conclusions. Noxious stimulation of latent TrPs induces abnormal autonomic nervous system activity within the referred pain zone. The observed phenomenon supports the concept of central nervous system involvement in the referred pain patomechanizm.

Post-amputation pain: Comparing pain presentations between adults with and without increased amputated-region sensitivity

OBJECTIVE

Among adults with persistent post-amputation pain, increased amputated-region pain sensitivity may reflect peripheral sensitization or indicate underlying central sensitization. To determine whether underlying central sensitization may contribute to increased pain sensitivity in this population, this study compared clinical signs and symptoms associated with central sensitization between adults with post-amputation pain who demonstrate or lack increased amputated-region sensitivity (as compared to reference data).

DESIGN

Cross-sectional.

SUBJECTS

Ninety-nine adults (60 with a unilateral, transtibial amputation and post-amputation pain, 39 pain-free controls with intact limbs).

METHODS

Participants underwent pain-pressure threshold testing of amputated-region and secondary (non-amputated region) sites and completed outcome measures assessing central sensitization symptoms (Patient-Reported Outcomes Measurement Information System® pain intensity and interference domains, Central Sensitization Inventory). Among the full sample, the presence and frequency of specific central sensitization symptoms were evaluated. Participants with post-amputation pain were then grouped based on whether normalized, amputated-region pain-pressure thresholds fell below (i.e., sensitive) or above (i.e., non-sensitive) the 25th percentile of sex-specific reference data. Between-group differences in normalized secondary-site sensitivity were evaluated using a multivariate analysis of variance; central sensitization symptom scores were compared using a Kruskal-Wallis test.

RESULTS

Noteworthy symptoms associated with central sensitization (e.g., fatigue, sleep disturbance, cognitive difficulty) were reported by 33%-62% of participants. Secondary-site pain sensitivity was greater among individuals with increased amputated-region sensitivity (n = 24) compared to peers without increased amputated-region sensitivity ([n = 36], mean difference > 1.33 standard deviation [SD], p < 0.001). Central sensitization symptom scores, however, were similar between groups (p > 0.187).

CONCLUSIONS

Participants with increased amputated-region sensitivity demonstrate generalized, secondary-site pain hypersensitivity, potentially indicating underlying central sensitization. Central sensitization symptom scores, however, were similar between groups, suggesting differences in physiological pain sensitivity may not manifest in subjective post-amputation pain descriptions.

Restless legs syndrome in patients with chronic low back pain

Background

Based on studies showing that both chronic low back pain (LBP) and restless legs syndrome (RLS) have similar pathophysiological mechanisms, we aimed to investigate the prevalence of RLS in patients with chronic LBP and to define which demographic and clinical features are prominent in those with LBP accompanied by RLS.

Methods

One hundred and two eligible, volunteer participants with chronic LBP were enrolled in this study. Visual analog scale (VAS), the Oswestry Disability Index (ODI), Pittsburgh Sleep Quality Index, Beck Depression Inventory, and Short Form-36 scales were applied to the patients. All patients were evaluated face-to-face for RLS using the International RLS study group diagnostic criteria.

Results

Most of our patients were women (52%). The mean age was 40.96±13.34 years and the mean disease duration was 46.16±41.98 months. RLS was detected in 36 (35.3%) of the patients with LBP. It was found that the female gender was more dominant in patients with RLS and the difference was statistically significant (p < 0.001). The amount of coffee intake was significantly higher in patients with RLS compared to those without RLS (p = 0.001). The disease duration for LBP was significantly higher in the patients with RLS (p = 0.003). VAS score, ODI score, PUKI score, and Beck depression score were significantly higher in the RLS group (p value were 0.048, 0.040, 0.007, and 0.043, respectively). In the evaluation of quality of life, all parameters except role emotional limitations and mental health were found to be significantly worse in the RLS group.

The Effect of Spinal Muscle Fatigue and Psychosocial Factors on Pressure-Pain Threshold in Healthy Adults

Objective

Pain sensitivity decreases following isometric exercise. It is not clear whether this exercise-induced hypoalgesia (EIH) occurs to the same extent in men and women. It is also unclear if the effect is systemic or local to the exercised musculature. The aim of our study was to investigate whether fatiguing isometric exercise of the spinal and hip extensors would result in increased pressure pain threshold (PPT) at sites local to and remote from the exercised muscles in healthy men and women and whether there is a relationship between central sensitization, psychosocial factors, and PPT.

Subjects

35 healthy adults (age 27.1 ± 4.5 years, 22 women).

Methods

This was a within-subjects cohort study. Participants completed questionnaires quantifying central sensitization, pain catastrophizing, sleepiness/insomnia, anxiety, and depression. PPT was assessed at the lumbar and thoracic paraspinals, hamstrings, gastrocnemius, wrist, and third digit before and immediately after participants performed the Biering-Sorensen test to failure.

Results

PPT increased postexercise in the thoracic paraspinals, hamstrings, and gastrocnemius in men and women and in the lumbar paraspinals in men only but did not change at the wrist and digit sites. A lower average PPT at baseline was associated with a higher central sensitization scores. A greater increase in average PPT postfatigue was significantly associated with higher average PPT at baseline.

Conclusions

Exercise-induced hypoalgesia occurs at sites overlying the muscles involved in fatiguing exercise, but not at remote sites, and is more evident in males than females. The magnitude of EIH depends upon baseline PPT. Even in healthy individuals, greater central sensitization is associated with lower baseline PPT.

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

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