The Mediating Role of Pain Cognitions and Pain Sensitivity in the Treatment Effect of Perioperative Pain Neuroscience Education in People Undergoing Surgery for Lumbar Radiculopathy.

Though perioperative pain neuroscience education (PPNE) positively influences patients' surgical outcomes, little is known about the mechanisms behind this treatment's success. Therefore, this study aims to evaluate the potential mediating role of pain cognitions and pain sensitivity in the treatment effect of PPNE on postoperative quality of life in people undergoing surgery for lumbar radiculopathy. This secondary analysis uses data from 120 participants of a randomized controlled trial who were randomized to receive either PPNE or perioperative biomedical education before undergoing surgery for lumbar radiculopathy. Quality of life was assessed 1-year postsurgery using the short form 36-item health survey (SF36) physical and mental component scores. Potential mediators included pain cognitions (ie, kinesiophobia, pain catastrophizing, and hypervigilance) and pain sensitivity (ie, endogenous nociceptive modulation), assessed 6 weeks postsurgery. Mediation models were constructed using structural equation modeling, and 95% confidence intervals (CIs) were calculated using 10,000 bootstrap samples. Analyses show a significant total effect for PPNE (estimate = .464, 95% CI [.105, .825]) and a significant indirect effect via pain catastrophizing on the SF36 physical component (estimate = .124, 95% CI [.001, .293]). No mediating effect was found through the remaining pain cognitions or pain sensitivity measures. Also, no potential mediators were identified for the treatment effect of PPNE on the SF36 mental component. Our findings suggest that pain catastrophizing mediates the treatment effect of PPNE on physical health-related quality of life in people undergoing surgery for lumbar radiculopathy. PERSPECTIVE: This secondary analysis identified pain catastrophizing as a mediator for PPNE in people undergoing surgery for lumbar radiculopathy. More so, its findings indicate that this educational intervention can enhance the postoperative physical health-related quality of life of these patients by addressing their catastrophizing thoughts. TRIAL REGISTRATION: Clinicaltrials.gov (NCT02630732).

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.

Personalized Multimodal Lifestyle Intervention as the Best-Evidenced Treatment for Chronic Pain: State-of-the-Art Clinical Perspective.

Chronic pain is the most prevalent disease worldwide, leading to substantial disability and socioeconomic burden. Therefore, it can be regarded as a public health disease and major challenge to scientists, clinicians and affected individuals. Behavioral lifestyle factors, such as, physical (in)activity, stress, poor sleep and an unhealthy diet are increasingly recognized as perpetuating factors for chronic pain. Yet, current management options for patients with chronic pain often do not address lifestyle factors in a personalized multimodal fashion. This state-of-the-art clinical perspective aims to address this gap by discussing how clinicians can simultaneously incorporate various lifestyle factors into a personalized multimodal lifestyle intervention for individuals with chronic pain. To do so the available evidence on (multimodal) lifestyle interventions targeting physical (in)activity, stress, sleep and nutritional factors, specifically, was reviewed and synthetized from a clinical point of view. First, advise is provided on how to design a personalized multimodal lifestyle approach for a specific patient. Subsequently, best-evidence recommendations on how to integrate physical (in)activity, stress, sleep and nutritional factors as treatment targets into a personalized multimodal lifestyle approach are outlined. Evidence supporting such a personalized multimodal lifestyle approach is growing, but further studies are needed.

Pain neuroscience education for patients with chronic pain: A scoping review from teaching-learning strategies, educational level, and cultural perspective.

OBJECTIVE: (1) To identify the characteristics of PNE programs in terms of teaching-learning strategies, session modality, content delivery format, number of sessions, total minutes and instructional support material used in patients with chronic musculoskeletal pain, (2) to describe PNE adaptations for patients with different educational levels or cultural backgrounds, and (3) to describe the influence of the patient's educational level or cultural background on the effects of PNE. METHODS: The PRISMA guideline for scoping reviews was followed. Nine databases were systematically searched up to July 8, 2023. Articles that examined clinical or psychosocial variables in adults with chronic musculoskeletal pain who received PNE were included. RESULTS: Seventy-one articles were included. Studies found benefits of PNE through passive/active teaching-learning strategies with group/individual sessions. However, PNE programs presented great heterogeneity and adaptations to PNE were poorly reported. Most studies did not consider educational level and culture in the effects of PNE. CONCLUSIONS: Despite the large number of studies on PNE and increased interest in this intervention, the educational level and culture are poorly reported in the studies. PRACTICAL IMPLICATIONS: It is recommended to use passive and/or active teaching-learning strategies provided in individual and/or group formats considering the patient's educational level and culture.

Effect of perceived injustice-targeted pain neuroscience education compared with biomedically focused education in breast cancer survivors: a study protocol for a multicentre randomised controlled trial (BCS-PI trial).

INTRODUCTION: Current treatments for pain in breast cancer survivors (BCSs) are mostly biomedically focused rather than biopsychosocially driven. However, 22% of BCSs with pain are experiencing perceived injustice, which is a known predictor for adverse pain outcomes and opioid prescription due to increased maladaptive pain behaviour. Educational interventions such as pain neuroscience education (PNE) are suggested to target perceived injustice. In addition, motivational interviewing can be an effective behavioural change technique. This trial aims to examine whether perceived injustice-targeted PNE with the integration of motivational interviewing is superior to biomedically focused pain education in reducing pain after 12 months in BCS with perceived injustice and pain. In addition, improvements in quality of life, perceived injustice and opioid use are evaluated, and a cost-effectiveness analysis will finally result in a recommendation concerning the use of perceived injustice-targeted PNE in BCSs with perceived injustice and pain. METHODS AND ANALYSIS: This two-arm multicentre randomised controlled trial will recruit female BCS (n=156) with pain and perceived injustice. Participants will be randomly assigned to perceived injustice-targeted PNE or biomedically focused pain education in each centre. Both interventions include an online session, an information leaflet and three one-to-one sessions. The primary outcome (pain), secondary outcomes (quality of life, perceived injustice and outcomes for cost-effectiveness analysis) and explanatory outcomes (pain phenotyping, sleep, fatigue and cognitive-emotional factors) will be assessed at baseline and at 0, 6, 12 and 24 months postintervention using self-reported questionnaires online. Treatment effects over time will be evaluated using linear mixed model analyses. Additionally, a cost-utility analysis will be done from a healthcare payer and societal perspective. ETHICS AND DISSEMINATION: The ethical agreement was obtained from the Main Ethics Committee (B.U.N.1432020000068) at the University Hospital Brussels and all other participating hospitals. Study results will be disseminated through presentations, conferences, social media, press and journals. TRIAL REGISTRATION NUMBER: NCT04730154.

Influence of Preoperative Pain, Cognitions, and Quantitative Sensory Testing Measures on the Effects of Perioperative Pain Neuroscience Education for People Receiving Surgery for Lumbar Radiculopathy: Secondary Analysis of a Randomized Controlled Trial.

OBJECTIVE: To explore whether preoperative pain intensity, pain cognitions, and quantitative sensory measures influence the established effectiveness of perioperative pain neuroscience education (PPNE) on health-related quality of life at 1 year after surgery for lumbar radiculopathy. DESIGN: Secondary analysis of a triple-blinded randomized controlled trial. METHODS: Participants (n = 90) were Dutch-speaking adults (18-65 years) who were scheduled for surgery for lumbar radiculopathy in 3 Belgian hospitals. They were randomized (1:1) to receive PPNE (n = 41) or perioperative biomedical education (n = 49). Linear mixed models were built for health-related quality of life (ie, SF-6D utility values, Physical and Mental Component of the 36-item Short Form Health Survey) using the following independent variables: therapy, time, and preoperative scores for back and leg pain intensity, pain catastrophizing, kinesiophobia, hypervigilance, and quantitative sensory measures. RESULTS: The impact of PPNE on SF-6D utility values over time was influenced by kinesiophobia (F = 3.30, P = .02) and leg pain intensity (F = 3.48, P = .02). Regardless of the intervention, back pain intensity negatively influenced SF-6D values over time (F = 3.99, P = .009). The Physical Component scores were negatively impacted by back pain intensity (F = 9.08, P = .003) and were influenced over time by leg pain intensity (F = 2.87, P = .04). The Mental Component scores were negatively impacted by back pain intensity (F = 6.64, P = .01) and pain catastrophizing (F = 5.42, P = .02), as well as hypervigilance (F = 3.16, P = .03) and leg pain intensity (F = 3.12, P = .03) over time. CONCLUSION: PPNE may be more effective than perioperative biomedical education in improving postoperative health utility values in patients who reported higher kinesiophobia and leg pain intensity before surgery for lumbar radiculopathy. J Orthop Sports Phys Ther 2024;54(4):1-10. Epub 8 January 2024. doi:10.2519/jospt.2024.12051.

Integration of Cognitive Behavioral Therapy for Insomnia in Best-Practice Care for Patients With Knee Osteoarthritis and Insomnia: A Randomized Controlled Trial Protocol.

OBJECTIVE: Knee osteoarthritis (KOA) is a common musculoskeletal problem worldwide and its key symptom is pain. Guidelines recommend incorporating comorbidity-specific therapies into patient-centered care. Patients diagnosed with KOA frequently have insomnia, which is associated with higher-pain severity. For this reason, this study protocol outlines the methodology of a randomized controlled trial (RCT) investigating the effectiveness of cognitive behavioral therapy for insomnia (CBTi) combined with best-practice KOA care (BPC) compared to best-practice KOA care and lifestyle education. METHODS: A 2-arm RCT in patients with KOA and insomnia is conducted, in which a total of 128 patients are randomly allocated to an intervention or control group. The experimental intervention consists of 12 sessions of physical therapist-led BPC with an additional 6 sessions of CBTi. The control intervention also receives BPC, which is supplemented with 6 general lifestyle information sessions. The primary outcome is the between-group difference in change in pain severity at 6 months after intervention. Secondary outcomes are pain-related outcomes, sleep-related outcomes, symptoms of anxiety and depression, level of physical activity and function, perceived global improvement, biomarkers of inflammation, and health-related quality of life. Assessments are conducted at baseline, immediately after intervention, and 3, 6, and 12 months after intervention. Furthermore, a cost-utility analysis for the proposed intervention will be performed alongside the RCT. IMPACT: This is the first RCT investigating the clinical and cost-effectiveness of a physical therapist-led intervention integrating CBTi into BPC in patients with KOA and insomnia. The results of this trial will add to the growing body of evidence on the effectiveness of individualized and comorbidity-specific KOA care, which can inform clinical decision-making and assist policymakers and other relevant stakeholders in optimizing the care pathway for patients with KOA.

Perceived Injustice in Cancer Survivors: Population-Specific Cut-Off Score and Relations with Personal Factors, Symptoms and Quality of Life-A Cross-Sectional Study.

Fatigue and pain are the most common side effects impacting quality of life (QoL) in cancer survivors. Recent insights have shown that perceived injustice (PI) can play a substantial role in these side effects, but research on cancer survivors is scarce. Furthermore, guidelines for recognizing clinically relevant levels of PI in cancer survivors are missing. The aims of this study are to provide a clinically relevant cut-off for PI and to explore relationships between personal characteristics, symptoms, and QoL with PI. This multicenter, cross-sectional study uses the Injustice Experience Questionnaire (IEQ), Numeric Pain Rating Scale (NPRS), Patient-Specific Complaints (PSC), Multidimensional Fatigue Index (MFI), and European Organization for Research and Treatment of Cancer QoL Questionnaire-C30 (EORTC-QLQ-C30). A clinical cut-off for PI was identified based on the 75th percentile of IEQ scores. Univariate and multivariate regressions explored the relationship between PI and personal characteristics (sex, age, cancer type, treatment type), symptoms (pain intensity, fatigue), and QoL (daily activity complaints, cancer-related QoL). Cancer survivors (n = 121) were included, and a cut-off of 20 was identified. Significant indirect associations were found between chemotherapy, NPRS, PSC, MFI, and EORTC-QLQ-C30 with PI. In the multivariate model, only MFI (B = 0.205; 95% CI: 0.125-0.018) and age (B = 0.086; 95% CI: -0.191-0.285) maintained a significant association with PI.

Unravelling Impaired Hypoalgesia at Rest and in Response to Exercise in Patients with Chronic Whiplash-Associated Disorders: Effects of a Single Administration of Selective Serotonin Reuptake Inhibitor versus Selective Norepinephrine Reuptake Inhibitor.

(1) Background: Noradrenaline and serotonin have modulatory roles in pain signaling and in exercise-induced hypoalgesia. Patients with chronic whiplash-associated disorders often show impaired exercise-induced hypoalgesia. Therefore, this study aimed to examine the isolated effect of activating serotonergic or noradrenergic descending pathways on hypoalgesia at rest and in response to exercise in patients with chronic WAD by using respectively a single dose of a selective serotonin reuptake inhibitor (SSRI) and a selective norepinephrine reuptake inhibitor (NRI). (2) Methods: Twenty-five people with chronic WAD participated in this double-blind randomized controlled crossover experiment. Serotonin and noradrenaline concentrations were modulated by the oral ingestion of a single dose of citalopram (i.e., SSRI) or atomoxetine (i.e., SNRI). Quantitative sensory testing (including pressure pain thresholds and conditioned pain modulation) was measured before and after exercise in combination with no medication (1), atomoxetine (2), or citalopram (3) at three different test days. (3) Results: Random-intercept linear mixed models analysis was used to analyze pain outcomes (i.e., pain at rest and exercise-induced hypoalgesia) before and after exercise over the three conditions in patients with chronic WAD. No differences in pain at rest were found between the three conditions before exercise. The effect of exercise on pain outcome measures was not influenced by medication intake. The occupational status of the participants had a significant influence on the effect of exercise and medication on pain outcomes (p < 0.05). Patients working full-time had some positive effect of atomoxetine on pain facilitation (p < 0.05). Unemployed patients had some negative effect of citalopram on pain tolerance and experienced exercise-induced hypoalgesia (p < 0.05). (4) Conclusions: A single dose of citalopram or atomoxetine did not result in changes in hypoalgesia at rest and in response to exercise. These results do not support the use of SSRI or selective NRI to overcome impaired hypoalgesia at rest or in response to exercise in people with chronic WAD. Effect of exercise and medication on pain in patients with chronic WAD is influenced by the occupational status.

Effect of perioperative pain neuroscience education in people undergoing surgery for lumbar radiculopathy: a multicentre randomised controlled trial.

BACKGROUND: Perioperative education should be improved to decrease unfavourable outcomes after lumbar surgery. This trial aimed to compare effectiveness in terms of pain, quality of life, pain cognition, surgical experience, healthcare use, work resumption, and cost-effectiveness of perioperative pain neuroscience education (PPNE) vs traditional biomedical education (perioperative biomedical education [PBE]) in people undergoing surgery for lumbar radiculopathy. METHODS: In this multicentre RCT (ClinicalTrials.gov: NCT02630732), patients undergoing surgery for lumbar radiculopathy in three Belgian hospitals were randomised to receive PPNE or PBE. Both groups received one preoperative and one postoperative one-to-one education session and a booklet (balanced interventions), with an essentially different content (PPNE: biopsychosocial; PBE: biomedical). Pain was the primary outcome (Visual Analogue Scales+quantitative sensory testing). Assessments were at 3 days, 6 weeks, and 6 and 12 months after surgery. RESULTS: Between March 2016 and April 2020, participants were randomly assigned to PPNE (n=58) or PBE (n=62). At 12 months, PPNE did not lead to significantly better pain outcomes, but it did result in more favourable 36-item Short Form Health Survey physical component (additional increase: 46.94; 95% confidence interval [CI]: 14.16-79.73; medium effect), Tampa Scale of Kinesiophobia (additional decrease: 3.15; 95% CI: 0.25-6.04; small effect), and Pain Catastrophising Scale (additional decrease: 6.18; 95% CI: 1.97-10.39; medium effect) scores. Females of the PPNE group showed higher probability for work resumption (95% vs 60% in the PBE group). PPNE was cost-effective compared with PBE (incremental costs: €-2732; incremental quality-adjusted life years: 0.012). CONCLUSIONS: Perioperative pain neuroscience education showed superior clinical and cost-effectiveness than perioperative biomedical education in people undergoing surgery for lumbar radiculopathy. CLINICAL TRIAL REGISTRATION: NCT02630732.

The Biology of Placebo and Nocebo Effects on Experimental and Chronic Pain: State of the Art.

(1) Background: In recent years, placebo and nocebo effects have been extensively documented in different medical conditions, including pain. The scientific literature has provided strong evidence of how the psychosocial context accompanying the treatment administration can influence the therapeutic outcome positively (placebo effects) or negatively (nocebo effects). (2) Methods: This state-of-the-art paper aims to provide an updated overview of placebo and nocebo effects on pain. (3) Results: The most common study designs, the psychological mechanisms, and neurobiological/genetic determinants of these phenomena are discussed, focusing on the differences between positive and negative context effects on pain in experimental settings on healthy volunteers and in clinical settings on chronic pain patients. Finally, the last section describes the implications for clinical and research practice to maximize the medical and scientific routine and correctly interpret the results of research studies on placebo and nocebo effects. (4) Conclusions: While studies on healthy participants seem consistent and provide a clear picture of how the brain reacts to the context, there are no unique results of the occurrence and magnitude of placebo and nocebo effects in chronic pain patients, mainly due to the heterogeneity of pain. This opens up the need for future studies on the topic.

The Role of Serotonergic and Noradrenergic Descending Pathways on Performance-Based Cognitive Functioning at Rest and in Response to Exercise in People with Chronic Whiplash-Associated Disorders: A Randomized Controlled Crossover Study.

(1) Background: Dysregulation in serotonergic and noradrenergic systems may be implicated in the neurobiophysiological mechanisms underlying pain-related cognitive impairment in chronic whiplash-associated disorders (CWAD). This study aimed to unravel the role of serotonergic and noradrenergic descending pathways in cognitive functioning at rest and in response to exercise in people with CWAD. (2) Methods: 25 people with CWAD were included in this double-blind, randomized, controlled crossover study. Endogenous descending serotonergic and noradrenergic inhibitory mechanisms were modulated by using a single dose of a selective serotonin reuptake inhibitor (Citalopram) or a selective norepinephrine reuptake inhibitor (Atomoxetine). Cognitive performance was studied at rest and in response to exercise (1) without medication intake; (2) after intake of Citalopram; and (3) after intake of Atomoxetine. (3) Results: After Atomoxetine intake, selective attention improved compared with the no medication day (p < 0.05). In contrast, a single dose of Citalopram had no significant effect on cognitive functioning at rest. When performing pairwise comparisons, improvements in selective attention were found after exercise for the no medication condition (p < 0.05). In contrast, after intake of Citalopram or Atomoxetine, selective and sustained attention worsened after exercise. (4) Conclusions: A single dose of Atomoxetine improved selective attention only in one Stroop condition, and a single dose of Citalopram had no effect on cognitive functioning at rest in people with CWAD. Only without medication intake did selective attention improve in response to exercise, whereas both centrally acting medications worsened cognitive performance in response to a submaximal aerobic exercise bout in people with CWAD.

The Prevalence of Perceived Injustice and Factors Associated With Perceived Injustice in People With Pain: A Systematic Review With Meta-analysis.

BACKGROUND: Perceived injustice (PI) is a multidimensional appraisal cognition comprising the severity of loss consequent to injury, blame, a sense of unfairness, and/or irreparability of loss. PI gained increasing interest in pain research since it potentially contributes to the experience and burden of (chronic) pain. OBJECTIVES: This systematic review aimed to determine the prevalence of PI and factors associated with PI in people with pain. STUDY DESIGN: Systematic review with meta-analysis. METHODS: Web of Science, PubMed, and Embase were screened for cross-sectional or cohort studies encompassing human patients who were diagnosed with a condition causing pain and reported prevalence rates for PI and/or associations between a factor and PI. Meta-analyses were carried out, and subgroup analyses were undertaken based on the methodological quality of the studies, the type of pain population, and whether the outcome measure was valid or not in case of heterogeneity (P < 0.05). RESULTS: Fifty-four studies were found eligible. The prevalence of PI ranged from 23% to 77% (I2 = 99%, P < 0.001). Association with PI, assessed using the Injustice Experienced Questionnaire, were found with pain catastrophizing (pooled Pearson's r [rp] = 0.66 [0.64, 0.69], P < 0.00001), posttraumatic stress (rp = 0.63 [0.59, 0.67], P < 0.00001), anger (rp = 0.59 [0.49, 0.67], P < 0.00001), anxiety (rp = 0.59 [0.52, 0.64], P < 0.00001), pain acceptance (rp = -0.59 [-0.66, -0.49], P < 0.00001), depressive symptoms (rp = 0.57 [0.52, 0.60], P < 0.00001), kinesiophobia (rp = 0.57 [0.50, 0.64], P < 0.00001), academic functioning (rp = -0.54 [-0.65, -0.41], P < 0.00001), disability (rp = 0.53 [0.47, 0.59], P < 0.00001), emotional functioning (rp = -0.52 [-0.64, -0.39], P < 0.00001), pain interference (rp = 0.49 [0.35, 0.60], P < 0.00001), state anger (rp = 0.48 [0.41, 0.54], P < 0.00001), mental functioning (rp = -0.48 [-0.57, -0.38], P < 0.00001), symptoms of central sensitization (rp = 0.47 [0.39, 0.55], P < 0.00001), social functioning (rp = -0.47 [-0.60, -0.31], P < 0.00001), and physical functioning (rp = -0.43 [-0.53, -0.33], P < 0.00001), pain perceptions (rp = 0.40 [0.40, 0.64], P < 0.00001), trait anger (rp = 0.40 [0.29, 0.49], P < 0.00001), pain intensity (rp = 0.37 [0.33, 0.42], P < 0.00001), and anger inhibition (rp = 0.35 [0.26, 0.43], P < 0.00001). LIMITATIONS: Some articles had to be excluded due to the absence of a full-text version. The findings can largely be applied to developed and high-income countries, but further research is needed in developing countries. Also, no validated cutoff values were available for the National Institutes of Health to determine the methodological quality of the included studies. Lastly, high heterogeneity was observed in many of the performed analyses. However, this was addressed by performing subgroup analyses, which could decrease heterogeneity in some cases. CONCLUSIONS: The prevalence of PI was >= 33% in 75% of the studies indicating that PI is important to consider in people with pain. There is evidence for the association of PI with psychological, pain, and quality of life characteristics in people with pain. The associations of PI with personal, injury, and recovery characteristics were overall not significant or negligible.

Exploring Associations between Healthcare Use and Demographics, Pain and Pain Cognitions in People Scheduled for Surgery for Lumbar Radiculopathy: A Cross-Sectional Study.

This cross-sectional study explored associations between demographics, pain intensity and cognitions on the one hand and healthcare use (HCU) on the other hand in people undergoing surgery for lumbar radiculopathy. HCU during the 2 months preceding surgery was evaluated using a retrospective questionnaire. Demographics included sex, age and level of education and equivalent income. Back and leg pain intensity were evaluated using a visual analogue scale. Pain cognitions were assessed with the Tampa scale of kinesiophobia, the pain catastrophizing scale and the pain vigilance and awareness questionnaire. The sample comprised 120 participants (52% males; 49 years (Quartile (Q)1-Q3: 37.3-57.43)). The number of visits to the general practitioner was associated with sex (incidence rate ratio (IRR) for males = 0.811; p = 0.050), pain catastrophizing (IRR = 1.010; p = 0.041), pain magnification (IRR = 1.058; p = 0.004) and leg pain intensity (IRR = 1.004; p = 0.038). The number of neurosurgeon visits was associated with level of education (IRR moderate education = 1.518; p = 0.016 (reference: low education)). Receiving zero physiotherapy visits was associated with higher back pain intensity (Beta = 0.018; p = 0.028). Highest level of analgesics used was associated with sex (IRR for males = 0.502; p = 0.047) and leg pain (IRR = 1.014; p = 0.034). Only the association between general practitioner visits and pain magnification remained significant in multivariable analyses (IRR = 1.061; p = 0.033). The results suggest a rather indirect relationship between HCU and demographics, pain intensity and cognitions, involving a potential interplay between several patient- and healthcare system-related factors.

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.

Experimental Pain Measurements Do Not Relate to Pain Intensity and Pain Cognitions in People Scheduled for Surgery for Lumbar Radiculopathy.

OBJECTIVE: The present cross-sectional study aims to unravel associations of pain intensity and cognitions with quantitative sensory testing in people scheduled for surgery for lumbar radiculopathy. Additionally, insight will be provided into the presence of dysfunctional nociceptive processing and maladaptive pain cognitions in this population. DESIGN: Cross-sectional study. SETTING: Data from three hospitals in Belgium. SUBJECTS: The final sample comprised 120 participants with lumbar radiculopathy scheduled for surgery, included between March 2016 and April 2019. METHODS: Self-reported pain intensity was assessed on a visual analog scale, and pain cognitions were assessed with self-reported questionnaires (Pain Catastrophizing Scale, Tampa Scale for Kinesiophobia, and Pain Vigilance and Awareness Questionnaire). Quantitative sensory testing (detection thresholds, pain thresholds, temporal summation, and conditioned pain modulation) was evaluated, as well. RESULTS: Evidence was found for the presence of an impaired inhibitory response to nociceptive stimuli and maladaptive pain cognitions in this population. Kinesiophobia was found to be present to a maladaptive degree in the majority of the patients (n = 106 [88%]). Significant, but weak, associations between electrical pain thresholds at the sural nerves and leg pain intensity (sural nerve symptomatic side: r = -0.23; P = 0.01; non-symptomatic side: r = -0.22; P = 0.02) and kinesiophobia levels (sural nerve non-symptomatic side: r = -0.26; P = 0.006) were identified. CONCLUSIONS: Electrical detection thresholds and correlates for endogenous nociceptive facilitation and inhibition were not found to be related to any of the pain cognitions or to pain intensity in people scheduled to undergo surgery for lumbar radiculopathy.

The Predictive Value of Fear Avoidance Beliefs for Outcomes Following Surgery for Lumbar Degenerative Disease: A Systematic Review and Best Evidence Synthesis.

BACKGROUND: Currently, evidence regarding fear avoidance beliefs as potential predictors for lumbar surgery outcomes seems insufficient and strong conclusions are not yet available. OBJECTIVE: This systematic review aimed to evaluate the predictive value of preoperative fear avoidance beliefs for postoperative pain intensity, functional status, and health-related quality of life following surgery for lumbar degenerative disease. STUDY DESIGN: Systematic review and best evidence synthesis. METHODS: An extensive search was performed in PubMed/Medline, EMBASE, PsycINFO, CINAHL and the Cochrane library for articles published up until October 2021. Two independent reviewers performed the screening, data extraction, and quality assessment, with a third independent reviewer consulting to resolve any disagreement. Observational studies that included patients undergoing surgery for lumbar degenerative disease, as well as evaluated fear avoidance beliefs (i.e., pain-related fear, pain catastrophizing, pain anxiety) in relation to a surgical outcome measure (i.e., pain intensity, functional status and health-related quality of life) were included in the review. The CHARMS- and QUIPS-tools were used for data extraction and quality assessment, respectively. A best evidence synthesis was performed resulting in conclusions regarding strong, moderate, conflicting, and limited levels of evidence. RESULTS: A total of 24 studies (n = 17,881) were included in this review. Following best evidence synthesis, 3 included studies reported no significant predictive value of preoperative pain-related fear for postoperative pain intensity resulting in moderate evidence for this relationship. Moderate evidence was also found indicating no significant predictive value of preoperative pain-related fear for postoperative functional status, as 6 out of 8 relevant studies reported this result. Only one study reported on the predictive value of preoperative pain catastrophizing for postoperative health-related quality of life, resulting in limited evidence for the absence of this predictive relationship. All other relationships were found to have conflicting evidence. LIMITATIONS: To evaluate surgical outcome, only patient-reported outcome measures as used by spine registries were included. Thus, our findings cannot be extrapolated to all surgery outcomes following lumbar degenerative disease and should only be interpreted in relation to postoperative pain intensity, functional status, or health-related quality of life. CONCLUSION: Best evidence synthesis showed moderate evidence indicating that preoperative pain-related fear is not a significant predictor for postoperative pain and function following surgery for lumbar degenerative disease. Additionally, limited evidence was found for a lack of predictive value of preoperative pain catastrophizing for postoperative health-related quality of life. As current evidence regarding the predictive value of preoperative fear avoidance beliefs following such a surgery is mixed, further research is required before more definitive conclusions can be made.

Health-related quality of life deviations from population norms in patients with lumbar radiculopathy: associations with pain, pain cognitions, and endogenous nociceptive modulation.

PURPOSE: The primary goal of this study was to compare the health-related quality of life (HRQoL) of people with lumbar radiculopathy to age- and sex-adjusted population norms. Additionally, it aimed to explore the associations between the HRQoL difference scores and measures related to pain cognitions, pain intensity, and endogenous nociceptive modulation. METHODS: Using answers from the Short Form 36-item Health Survey and UK population norms, SF-6D difference scores were calculated. A one-sample t test was used to assess the SF-6D difference scores. Univariate and multivariate regression analyses were used to assess the associations between SF-6D difference scores and pain intensity [Visual Analogue Scale (VAS) for back and leg pain], pain cognitions [Pain Catastrophizing Scale (PCS), Tampa Scale for Kinesiophobia (TSK), Pain Vigilance and Awareness Questionnaire (PVAQ)], and correlates for endogenous nociceptive modulation using quantitative sensory testing. RESULTS: One hundred and twenty people with lumbar radiculopathy scheduled for surgery were included in this study. The mean SF-6D difference score of - 0.26 [SD = 0.09] was found to be significantly less than 0 [95%CI: - 0.27 to - 0.24]. Univariate analyses showed a significant influence from PCS, TSK, and PVAQ on the SF-6D difference scores. The final multivariate regression model included PCS and PVAQ, with only PCS maintaining a statistically significant regression coefficient [b = - 0.002; 95% CI: - 0.004 to - 0.001]. CONCLUSION: People diagnosed with lumbar radiculopathy report significantly lower HRQoL scores when compared with age- and sex-adjusted UK norm values. Even though all examined pain cognitions were found to have a significant association, pain catastrophizing showed the most significant relation to the SF-6D difference scores. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier No. NCT02630732. Date of registration: November 25, 2015.