The epidemiology and economic consequences of pain

Moving towards the use of artificial intelligence in pain management

BACKGROUND AND OBJECTIVE

While the development of artificial intelligence (AI) technologies in medicine has been significant, their application to acute and chronic pain management has not been well characterized. This systematic review aims to provide an overview of the current state of AI in acute and chronic pain management.

DATABASES AND DATA TREATMENT

This review was registered with PROSPERO (ID# CRD42022307017), the international registry for systematic reviews. The search strategy was prepared by a librarian and run in four electronic databases (Embase, Medline, Central, and Web of Science). Collected articles were screened by two reviewers. Included studies described the use of AI for acute and chronic pain management.

RESULTS

From the 17,601 records identified in the initial search, 197 were included in this review. Identified applications of AI were described for treatment planning as well as treatment delivery. Described uses include prediction of pain, forecasting of individualized responses to treatment, treatment regimen tailoring, image-guidance for procedural interventions and self-management tools. Multiple domains of AI were used including machine learning, computer vision, fuzzy logic, natural language processing and expert systems.

CONCLUSION

There is growing literature regarding applications of AI for pain management, and their clinical use holds potential for improving patient outcomes. However, multiple barriers to their clinical integration remain including lack validation of such applications in diverse patient populations, missing infrastructure to support these tools and limited provider understanding of AI.

SIGNIFICANCE

This review characterizes current applications of AI for pain management and discusses barriers to their clinical integration. Our findings support continuing efforts directed towards establishing comprehensive systems that integrate AI throughout the patient care continuum.

Electroacupuncture Alleviates Neuropathic Pain and Negative Emotion in Mice by Regulating Gut Microbiota

Background

Neuropathic pain (NP) is a prevalent chronic condition frequently accompanied by adverse emotional states. Previous research has demonstrated the clinical efficacy of electroacupuncture (EA) in mitigating neuropathic pain and its associated mood disorders. Recent studies have underscored a correlation between gut microbiota and both NP and negative emotional states. Nevertheless, the relationship between the modulation of gut microbiota by EA and the amelioration of NP remains inadequately understood.

Methods

Mice were randomly assigned to one of the three groups: the Control (Con) group, the EA group, and the Chronic Constrictive Injury (CCI) group (n = 12 each). Starting from the 8th day post-CCI induction, the EA group underwent EA treatment once every two days, for a total of 20 sessions. To investigate the impact of gut microbiota on CCI mice, we employed a variety of methods, including various behavioral tests and 16S ribosomal DNA (rDNA) sequencing.

Results

The results indicated that EA significantly ameliorated mechanical allodynia and emotional dysfunction induced by CCI in mice. Analysis through 16S rDNA sequencing revealed that the gut microbiota of NP model mice exhibited a marked increase in diversity. However, EA could partially reverse changes in the diversity of gut microbiota. The abundance of Alloprevotella, A2, Roseburia, Muribaculum, Ruminiclostridium, and Rikenella was increased, and the abundance levels of Bacteroides were decreased at the genus level in CCI mice. Following EA treatment, the relative abundance of Alistipes, A2, Roseburia, and Rikenella was decreased, whereas the relative abundance of Alloprevotella and Parabacteroides was increased in EA group when compared with the CCI group.

Conclusion

These findings suggested that EA exerted a significant therapeutic effect on NP, potentially through modulation of the gut microbiota.

Advancing pain education: a cross-sectional study in the Portuguese medical schools

INTRODUCTION

Chronic pain negatively impacts on quality of life and is often underreported and undertreated. Therefore, it is essential for medical schools to provide education in pain management for students. This study evaluated the current state of pain education in the Portuguese medical schools, focusing on integrating pain-related topics into the curriculum.

METHODS

A cross-sectional study was employed, involving all the eight public medicals schools in Portugal. The study, approved by the Ethics Committee of the Faculty of Medicine of the University of Porto, utilized a previous validated questionnaire sent via electronic mail. The data collection spanned from January 2023 to October 2023, and responses were analysed using the SPSS software for descriptive statistics.

RESULTS

All eight public medical schools responded to the questionnaire, providing insights into their pain education practices. Over the six years of medical education, 50% of the schools offered dedicated course content on chronic pain within the curriculum. This instruction is primarily provided in the second year, with variations in the hours for both theoretical and practical teaching. Additionally, 62.5% integrate pain-related topics into other discipline-based courses, predominantly in the fourth year. Post-graduate pain education activities were reported in only three of the eight schools (37.5%).

CONCLUSIONS

These findings represent the first analysis of pain education in public Portuguese Medical Schools. The findings indicate that enhancements in pain education through the introduction of mandatory pain topics, curriculum integration, and investment in post-graduation courses are needed. These improvements aim to provide medical students the essential knowledge and skills to proficiently manage the intricate challenges of chronic pain, thereby enhancing patients' quality of life and reducing social burdens.

Peripheral inflammation enhances opioid-induced gastrointestinal motility inhibition via up-regulating spinal mu opioid receptor

Opioids are potent analgesics in clinical pain management but exert variable analgesia in different pain types. Opioid-induced constipation is a common side effect of opioid therapy, and whether opioids induce different gastrointestinal motility inhibitions in different pain types is unknown. In this study, we evaluated the antinociceptive effects and inhibition of upper gastrointestinal transit and colonic bead expulsion of morphine, DAMGO, and Deltorphin in mouse CFA chronic inflammatory pain, SNI chronic neuropathic pain, and carrageenan chronic inflammatory pain models. Furthermore, quantitative PCR and immunofluorescence were used to investigate the mechanisms underlying the altered inhibition. Results showed that intrathecal administration of morphine, DAMGO, and Deltorphin produced higher antinociceptive effects in the CFA and carrageenan groups than in the SNI group. Upper gastrointestinal transit inhibition was significantly enhanced in the carrageenan group by morphine and DAMGO; colonic bead expulsion inhibition was also enhanced in the CFA and carrageenan groups by morphine and DAMGO, but not in Deltorphin treatment. Additionally, mu (MOR) opioid receptor mRNA and MOR-expressing cell density in the lumbar spinal cord of CFA and carrageenan mice were increased, whereas delta opioid receptor expression remained unchanged in these groups. Finally, the pharmacological blockade of MOR completely prevented the enhanced upper gastrointestinal transit inhibition in the carrageenan group by morphine and DAMGO. Altogether, our results indicate that gastrointestinal motility inhibition induced by MOR agonists can be enhanced with upregulated spinal MOR expression in chronic inflammatory pain.

Impact of different treatments for chronic pain on cognitive function: A systematic review

Introduction

Experimental evidence supports the hypothesis of reciprocal influence between neural systems involved in cognition and central pain processing circuits. Furthermore, studies have demonstrated bidirectional communication between central pain processing areas and the immune system, leading to changes in behaviour, sensory perception, mood, and cognition. However, the academic community has not yet reached a consensus on whether effective analgesic interventions can mitigate or reverse cognitive deterioration.

Methods

This systematic review evaluated the effectiveness of various therapeutic interventions in improving cognitive functions (primary outcome) and altering the profile of immunological markers (secondary outcome) in chronic pain patients. The review was limited to randomised controlled trials addressing chronic pain of any aetiology, with searches conducted in PubMed, EMBASE, and Scopus databases.

Results

The qualitative synthesis of twelve studies conducted between 2003 and 2021, involving 1432 participants in experimental (n = 950) and control (n = 482) groups, revealed some interesting patterns. Only half of the studies (6/12) reported cognitive improvement, with attention being the most analysed cognitive domain, followed by memory and executive function. Fibromyalgia was the most studied aetiology of chronic pain. The strategies of intervention/treatment and durations varied widely; however, milnacipran versus placebo emerged as the most frequently employed intervention. Only one study reported immunological markers, limiting the evaluation of this outcome.

Conclusion

Based on this analysis, it is not possible to affirm that interventions targeting chronic pain improve cognition. This review suggests new research directions and calls for more robust methodological approaches.

Does rehabilitation improve work participation in patients with chronic spinal pain after spinal surgery: a systematic review

OBJECTIVE

Patients with therapy-refractory chronic spinal pain after spinal surgery experience increased disability, resulting in substantial loss of employment and consequently lower quality of life. Despite findings that rehabilitation improves socio-economic outcomes in other chronic pain conditions, evidence for patients with chronic spinal pain after spinal surgery is limited. A systematic review was conducted to provide an overview of rehabilitation interventions and their effectiveness to improve work participation for patients with chronic spinal pain after spinal surgery.

METHODS

MEDLINE (via PubMed), Scopus, Embase, and Web of Science, were systematically searched. Risk of bias was assessed using the modified Downs and Black checklist and GRADE was used to assess certainty of evidence. The review protocol was prospectively registered on PROSPERO (CRD42022346091).

RESULTS

The search yielded 1,289 publications. Full-text screening of 48 articles resulted in the inclusion of 6 publications. The included interventions comprised multiple treatment components, consisting of back school, self-care, functional restoration, multidisciplinary rehabilitation, physiotherapy, and digital care programmes to improve work participation.

CONCLUSION

Rehabilitation to improve return to work for patients with chronic spinal pain after spinal surgery was supported only by low-certainty evidence. Rehabilitation therapies that are personalized and that integrate the patient's work seem most suitable.

Back pain Knowledge and beliefs Survey (BacKS): development and assessment of measurement properties

OBJECTIVE

To develop and evaluate a new patient-reported outcome measure (PROM) to assess people's knowledge and beliefs about low back pain.

METHODS

This study followed the COnsensus-based Standards for the selection of health Measurement INstruments guidelines. An 18-item preliminary version of the Back pain Knowledge and beliefs Survey (BacKS) was generated based on evidence-based key messages and current clinical guidelines for low back pain. Four items were added following input from three consumers and seven experts. Focus groups (n=9) confirmed content validity. The 22-item version was completed by 258 Australian-based adults (>18 years) with self-reported low back pain. A follow-up survey was sent 1 week later. The following measurement properties were evaluated to produce, and then assess the final version of BacKS: structural validity (exploratory factor analysis); internal consistency (Cronbach's alpha); test-retest reliability (intraclass correlation coefficient); measurement error (Smallest Detectable Change); construct validity (hypothesis tested: moderate positive Pearson correlation between BacKS and Back Beliefs Questionnaire); plus, interpretability and feasibility.

RESULTS

The final BacKS comprised 20 items with a 2-factor structure (biomedical factor: 9 items, score ranging from 9 to 45, and self-care factor: 11 items, score ranging from 11 to 55). Internal consistency and reliability were adequate (>0.70) for each factor. Smallest detectable change was 4.4 (biomedical factor) and 7.0 (self-care factor). Our construct validity hypothesis was confirmed (Pearson correlation=0.53). No floor or ceiling effects were detected.

CONCLUSION

The BacKS is a valid, reliable and feasible PROM to measure knowledge and beliefs about low back pain in clinical practice and research settings.

Effects of Transcutaneous Electrical Nerve Stimulation (TENS) During Functional Activities or Exercise: A Systematic Review

BACKGROUND

TENS is a non-pharmacological adjunctive treatment commonly recommended for analgesic purposes, with widespread use and acceptance in clinical practice; however, its effects simultaneously with exercise are controversial, and there are gaps regarding its effectiveness and applicability, especially regarding the parameters and protocols used to treat pain. In view of this, the aim of this study was to systematically review the effects of TENS applied simultaneously with functional activities or exercises in the treatment of individuals with pain.

METHOD

A bibliographic search was performed in electronic databases, including EMBASE, PubMED, Scopus, Web of Science, PEDro, SPORTDiscus, and the grey literature. The search yielded a total of 634 articles, of which only six met the inclusion criteria and were analysed individually. Of the selected studies, four evaluated the simultaneous use of TENS in patients with chronic pain, one in patients with fatigue-induced injury, and one in healthy subjects.

RESULTS

The articles selected for synthesis of the review were assessed using the RoB 2.0 risk of bias tool, which found that three of the included studies had a low risk of bias, while two studies were analysed as high risk and only one with some concern. It is concluded that the use of TENS in conjunction with functional activities and exercises may benefit people with pain.

CONCLUSION

The studies showed that the use of TENS with high frequency and intensity at the sensory threshold and applied simultaneously with exercise produced more significant analgesic effects, but new clinical trials with robust methodological designs should be carried out.

The associations between adverse childhood experiences and body pain among middle-aged and older adults: findings from China

BACKGROUND

Adverse Childhood Experiences (ACEs) have been implicated in the development of body pain, yet research on their impact on body pain and its progression remains scarce. This study aimed to examine the associations between ACEs and the presence and areas of body pain, as well as their developmental trajectories among middle-aged and older Chinese adults.

METHODS

We included participants aged 45 years and above from the China Health and Retirement Longitudinal Study (CHARLS) conducted between 2011 and 2018. Retrospective data on ACEs and pain sites were collected with questionnaires. The presence of pain at different body sites was categorized into three areas: head & neck, trunk, and limbs. ACEs consisted of ten types of adverse experiences and were cumulatively scored. For the cross-sectional analysis (2011), logistic regressions were performed to estimate the associations between ACEs and pain presence in specific areas. In the longitudinal analysis (2011-2018), we further applied group-based trajectory modelling (GBTM) to determine the developmental trajectories of body pain. Multinomial logistic regressions were then conducted to estimate the associations between ACEs and pain trajectories.

RESULTS

In the cross-sectional analysis (n = 8157), ACEs were positively associated with the presence of pain in the head & neck (odds ratio [OR] = 3.55, 95% confidence intervals [CI] = 2.37-4.74), trunk (OR = 3.28, 95% CI = 2.47-4.34), and limbs areas (OR = 2.30, 95% CI = 1.77-3.00) compared to no ACEs. These associations varied by sex and residence. In the longitudinal analysis (n = 5188), GBTM identified three developmental trajectories of body pain (n = 9521): high-increasing (7.44%), low-moderate (33.67%) and maintained-low trajectories (58.89%) trajectories. Compared to participants without ACEs, individuals had three ACEs and 4 or more ACEs were consistently associated with low-moderate (three ACEs: OR = 2.26, 95% CI = 1.81-2.83, four or more ACEs: OR = 3.11, 95% CI = 2.51-3.87) and high-increasing (three ACEs: OR = 3.28, 95% CI = 2.03-5.30, four or more ACEs: OR = 6.78, 95% CI = 4.30-10.68) body pain trajectories across sexes and residence.

CONCLUSION

This study highlighted the significant association between ACEs and body pain among middle-aged and older Chinese, emphasizing the importance of preventing or mitigating ACEs as a strategy for the prevention and management of body pain.

Chronic and Acute Pain and Adverse Economic Outcomes in a 9/11-Exposed Cohort

The objective of this study was to determine the association between acute and chronic pain and various economic and quality-of-life outcomes. The study sample was drawn from the World Trade Center Health Registry. Both acute and chronic pain were measured in 2020-2021. Logistic regression models were constructed to determine the odds of several economic and quality-of-life variables: early retirement, low household income, decline in household income, quality of life, and not working due to health. Those who had extreme pain in the last four weeks that interfered with normal work had 3.12 (95% confidence interval (CI): 2.36, 4.39) times the odds of early retirement, 5.34 (95% CI: 3.47, 8.21) times the odds of having a household income below USD 50,000, 2.56 (95% CI: 1.51, 4.33) times the odds of having an income decrease, and 14.4 (95% CI: 11.3, 18.3) times the rate of poor health days compared to those with no pain. Similar results were found for chronic pain. The detrimental effects of pain may influence multiple facets of a patient's life, and both financial and overall well-being may diminish even several years after a pain diagnosis.

Development and Validation of the Decisions to use Opioids Measure

BACKGROUND

Millions experience inadequately managed acute pain each year. Opioids are an important tool for managing pain; however, recent reductions in opioid prescriptions have exacerbated preexisting challenges in pain management. Moreover, patient expectations and desires for pain management may drive additional opioid use. There is an important need to characterize patient motivations for using opioids in order to develop promising interventions. The aim of this study was to develop the Decisions To use Opioids (DTO) measure.

METHODS

We used an exploratory sequential mixed methods design to create items for the DTO measure. Qualitative data from patient interviews and focus groups informed the development of items for the DTO. We evaluated the content validity of candidate items with nine experts using the content validity index (CVI) and conceptual significance. Face validity was assessed via cognitive interviews with five emergency department (ED) participants who experienced acute pain.

RESULTS

We generated an initial pool of 52 items. Expert ratings provided evidence of content validity on 40 items, as indicated by an item CVI score of 0.83 or higher. Nine items with CVI scores of <0.83 were retained and revised due to the conceptual significance. The remaining three items were discarded.

CONCLUSIONS

This study provided evidence of content and face validity of the DTO measure for ED patients. Further psychometric evaluation is needed to gather data regarding the DTO's internal consistency, construct validity, and criterion validity.

Infralimbic-basolateral amygdala circuit associated with depression-like not anxiety-like behaviors induced by chronic neuropathic pain and the antidepressant effects of electroacupuncture

Chronic pain, such as neuropathic pain, can lead to anxiety, depression, and other negative emotions, thereby forming comorbidities and increasing the risk of chronic pain over time. Both the infralimbic amygdala (IL) and the basolateral amygdala (BLA) are significantly associated with negative emotions and pain, and they are known to have reciprocal connections. However, the role of IL-BLA circuit pathways in neuropathic pain-induced anxiety and depression remains unexplored. Electroacupuncture (EA) is frequently employed in the treatment of chronic pain and emotional disorders. However, The mechanism by which EA mediates its analgesic and emotion-alleviating effects via the IL-BLA circuit remains uncertain. Here, we used chemogenetic manipulation combined with behavioral tests to detect pain induced anxiety-like and depression-like behaviors. We observed that activation of the IL-BLA circuit by chemogenetic activation induced depression-like behavior of mice. Additionally, we discovered that chemogenetic activation of the IL-BLA circuit successfully prevented the beneficial effects of EA on depression-like behavior brought on by chronic pain in mice with spared nerve injury (SNI). We discovered that SNI-induced depression-like behavior could be mitigated by inhibiting the circuit, and EA had a comparable depressive-relieving effect. Furthermore, the IL-BLA circuit's activation or inhibition had no effect on the anxiety-like feelings brought on by SNI. Overall, our findings identify a specific neural circuit that selectively regulates pain-induced depression-like emotions, without affecting pain-induced anxiety-like emotions. This discovery offers a precise target for future treatments of comorbid pain and depression and provides a plausible explanation for the efficacy of EA in treating depression-like emotions associated with chronic pain.

Social determinants of health and youth chronic pain

OBJECTIVES

To identify the relationships between social determinants of health (SDOH) and chronic pain among U.S. youth (referring to children and adolescents).

METHODS

Data including a national sample of U.S. youth were retrieved from the 2022 National Survey of Children's Health. Twenty indicators within five SDOH-related domains (e.i., economic stability, social and community context, neighborhood and built environment, health care access and quality, and education access and quality) were included. The presence of chronic pain was assessed using a self-reported question, answered by the main caregiver. Associations of SDOH-related indicators and youth chronic pain were estimated using multi-variable logistic regression models, while adjusting for covariates (e.g., age, sex, ethnicity, weight status, and movement behaviors).

RESULTS

Data from 30,287 U S. youth aged 6-17 years (median [SD] age, 11.59 [3.30] years; 14,582 girls [48.97 %]) were collected. In 7.5 % of the final sample size, caregivers reported that they had chronic pain. Youth grow up in conditions with diverse SDOH profiles, including food insufficiency (OR = 1.46, 95 % CI: 1.01 to 2.10) and parental unemployment (OR = 1.56, 95 % CI: 1.15 to 2.12); low school engagement (OR = 1.48, 95 % CI: 1.14 to 1.92) and low school safety (OR = 1.65, 95 % CI: 1.14 to 2.39); limited access to quality health care (OR = 2.56, 95 % CI: 2.12 to 3.09), a high frequency of hospital visits (OR = 4.76, 95 % CI: 1.82 to 12.44), and alternative health care (OR = 2.57, 95 % CI: 2.07 to 3.20); bullying victimization (OR = 1.37, 95 % CI: 1.11 to 1.68) and community-based adverse childhood experiences (OR = 1.64, 95 % CI: 1.32 to 2.05); and disadvantageous amenity characteristics (OR = 1.38, 95 % CI: 1.05 to 1.79); resulted in higher odds of presenting chronic pain.

CONCLUSIONS

Different indicators included in the SDOH domains were associated with a higher probability of presenting chronic pain in U.S youth. These findings have implied relationships between the SDOH and chronic pain in youth, requiring a comprehensive approach to addressing health equity to prevent and reduce the presence of youth chronic pain.

Bedside Neuromodulation of Persistent Pain and Allodynia with Caloric Vestibular Stimulation

BACKGROUND

Caloric vestibular stimulation (CVS) is a well-established neurological diagnostic technique that also induces many phenomenological modulations, including reductions in phantom limb pain (PLP), spinal cord injury pain (SCIP), and central post-stroke pain.

OBJECTIVE

We aimed to assess in a variety of persistent pain (PP) conditions (i) short-term pain modulation by CVS relative to a forehead ice pack cold-arousal control procedure and (ii) the duration and repeatability of CVS modulations. The tolerability of CVS was also assessed and has been reported separately.

METHODS

We conducted a convenience-based non-randomised single-blinded placebo-controlled study. Thirty-eight PP patients were assessed (PLP, n = 8; SCIP, n = 12; complex regional pain syndrome, CRPS, n = 14; non-specific PP, n = 4). Patients underwent 1-3 separate-day sessions of iced-water right-ear CVS. All but four also underwent the ice pack procedure. Analyses used patient-reported numerical rating scale pain intensity (NRS-PI) scores for pain and allodynia.

RESULTS

Across all groups, NRS-PI for pain was significantly lower within 30 min post-CVS than post-ice pack (p < 0.01). Average reductions were 24.8% (CVS) and 6.4% (ice pack). CRPS appeared most responsive to CVS, while PLP and SCIP responses were less than expected from previous reports. The strongest CVS pain reductions lasted hours to over three weeks. CVS also induced substantial reductions in allodynia in three of nine allodynic CRPS patients, lasting 24 h to 1 month. As reported elsewhere, only one patient experienced emesis and CVS was widely rated by patients as a tolerable PP management intervention.

CONCLUSIONS

Although these results require interpretative caution, CVS was found to modulate pain relative to an ice pack control. CVS also modulated allodynia in some cases. CVS should be examined for pain management efficacy using randomised controlled trials.

Lumbar Radicular Pain in the Eyes of Artificial Intelligence: Can You 'Imagine' What I 'Feel'?

OBJECTIVE

Pain is a complex sensory and emotional experience that significantly impacts individuals' well-being. Lumbar radicular pain (LRP) is a prevalent neuropathic pain affecting 9.9% to 25% of the population annually. Accurate identification of pain patterns in LRP is essential for diagnosis and management. Artificial intelligence has potential in health care but faces challenges in reliability and accuracy. This study aimed to investigate the accuracy and consistency of LRP patterns demonstrated by ChatGPT-4o.

METHODS

The study was conducted at Üsküdar State Hospital from June 1 to June 30, 2024, utilizing the Generative Pretrained Transformer (GPT), version 4o language model. ChatGPT-4o was prompted to generate and mark LRP patterns for L4, L5, and S1 radiculopathies on an anatomical model. The process was repeated after two weeks to assess consistency. The markings by ChatGPT were compared with those by two experienced specialists using OpenCV for analysis.

RESULTS

ChatGPT's initial and follow-up markings of L4, L5, and S1 radiculopathy pain patterns were statistically significantly different from each other and from the specialists' markings (P < 0.001 for all comparisons).

CONCLUSIONS

ChatGPT currently lacks the capacity to accurately and consistently represent LRP patterns. AI tools in health care require further refinement, validation, and regulation to ensure reliability and safety. Future research should involve multiple AI platforms and broader medical conditions to enhance generalizability.

The role and treatment potential of the complement pathway in chronic pain

The role of the complement system in pain syndromes has garnered attention on the back of preclinical and clinical evidence supporting its potential as a target for new analgesic pharmacotherapies. Of the components that make up the complement system, component 5a (C5a) and component 3a (C3a) are most strongly and consistently associated with pain. Receptors for C5a are widely found in immune resident cells (microglia, astrocytes, sensory neuron-associated macrophages (sNAMs)) in the central nervous system (CNS) as well as hematogenous immune cells (mast cells, macrophages, T-lymphocytes, etc.). When active, as is often observed in chronic pain conditions, these cells produce various inflammatory mediators including pro-inflammatory cytokines. These events can trigger nervous tissue inflammation (neuroinflammation) which coexists with and potentially maintains peripheral and central sensitization. C5a has a likely critical role in initiating this process highlighting its potential as a promising non-opioid target for treating pain. This review summarizes the most up-to-date research on the role of the complement system in pain with emphasis on the C5 pathway in peripheral tissue, dorsal root ganglia (DRG) and the CNS, and explores advances in complement-targeted drug development and sex differences. A perspective on the optimal application of different C5a inhibitors for different types (e.g., neuropathic, post-surgical and chemotherapy-induced pain, osteoarthritis pain) and stages (e.g., acute, subacute, chronic) of pain is also provided to help guide future clinical trials. PERSPECTIVE: This review highlights the role and mechanisms of complement components and their receptors in physiological and pathological pain. The potential of complement-targeted therapeutics for the treatment of chronic pain is also explored with a focus on C5a inhibitors to help guide future clinical trials.

Effects of Kinesio Taping on Neck Pain: A Meta-Analysis and Systematic Review of Randomized Controlled Trials

INTRODUCTION

Neck pain constitutes a prevalent and burdensome health issue, substantially impairing patients' quality of life and functional capabilities. Kinesio taping (KT), a commonly employed intervention within physical therapy, holds promise for mitigating such symptoms; however, a comprehensive evaluation of its efficacy and evidence base is lacking. Therefore, this study endeavors to systematically investigate the therapeutic effects of KT on both subjective neck pain intensity and objective measures of physical activity limitations through a rigorous meta-analytic approach. By synthesizing existing literature and scrutinizing methodological nuances, we aim to furnish healthcare practitioners with evidence-informed insights, facilitating more judicious clinical decision-making and optimizing patient outcomes.

METHODS

According to the PRISMA guidelines, we conducted searches on PubMed, Cochrane Library, Embase, and Web of Science for randomized controlled trials (RCTs) investigating the efficacy of KT in treating neck pain. Screening was performed based on predefined inclusion and exclusion criteria. Characteristics of the included RCTs were extracted. Trial heterogeneity was assessed using the I2 statistic. Meta-analysis was conducted using Stata 17 software. Risk of bias and methodological quality were evaluated using the Cochrane Risk of Bias 2 tool and the PEDro scale, respectively.

RESULTS

In our analysis of 10 RCTs involving 620 patients meeting our inclusion criteria, KT demonstrated significant beneficial effects on neck pain, notably surpassing conventional treatment (weighted mean difference = -0.897, 95% CI -1.30 to -0.49, P < 0.001). Subgroup analysis further revealed that KT exhibited particularly pronounced efficacy in the treatment of nonspecific neck pain and mechanical neck pain, with a more substantial effect observed after 4 weeks of KT intervention compared to 1 week. Moreover, KT demonstrated superior efficacy in alleviating pain symptoms compared to both conventional treatment and sham interventions.

CONCLUSION

KT has demonstrated efficacy in reducing neck pain and improving cervical dysfunction among patients. Prolonged KT treatment or its combination with other therapeutic modalities may potentially enhance therapeutic outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42024524685.

Formulation of nasal analgesic sprays with diclofenac sodium, ibuprofen, paracetamol, and evaluation of in vitro toxicity

OBJECTIVE

Intranasal analgesic sprays represent a safe, efficacious method for pain relief, with a shorter working time compared to oral painkillers. This study aimed to develop nasal sprays using commonly available over-the-counter analgesics, providing an alternative treatment option that is more convenient and potentially more effective in managing pain, particularly in pediatric patients.

METHODS

Three different nasal spray formulations with the contents of diclofenac sodium, ibuprofen, and paracetamol were created, and characterization studies were completed. The possible cytotoxic, genotoxic, and apoptotic effects of nasal sprays were studied on human normal skin fibroblastic cells (CCD-1079Sk) using WST cell viability test, alkaline single-cell gel electrophoresis analysis, and acridine orange/ethidium bromide staining, respectively.

RESULTS

The formulations' physical appearance and drug content were assessed, yielding nonsignificant results (p > 0.05). All formulations were determined at pH 5.5-6.2 so that the pH values of the prepared formulations were compatible with the pH value of the nasal mucosa. Selected nasal spray formulations were stable for 90 days, and the safe doses were chosen as 0.0625, 0.375, and 1.25 mg/mL for diclofenac, ibuprofen, and paracetamol, respectively, by not showing toxicity even at 24 h.

CONCLUSION

This study demonstrated that nasal sprays containing paracetamol, ibuprofen, and diclofenac sodium can be successfully formulated. These new formulations may provide alternative treatment and easier application for patients unable to swallow or refuse to take oral analgesics.

Impact of disabilities in activities of daily living on opioid use for chronic pain in older adults: an exploratory secondary analysis from ELSI-Brazil

OBJECTIVES

Problematic use of opioids by older adults is associated with adverse effects and has become a public health crisis worldwide. Ageing-related disabilities in activities of daily living (ADL) could promote unnecessary use of opioids in this population. This study evaluates the association between ADL disability and opioid consumption in Brazilian older adults.

STUDY DESIGN

Study design- cross-sectional secondary data analysis of the second wave of the Brazil Longitudinal Study of Ageing (ELSI-Brazil).

METHODS

Data from the second wave of the Brazil Longitudinal Study of Ageing (ELSI-Brazil) were used. Older adults with chronic pain were included. ADL disability was measured using the Katz Index. The primary outcome was opioid consumption for chronic pain. The primary association was explored using logistic regression models adjusting for predetermined confounders. Sensitivity analyses evaluating model performance were done by calibrating and validating the model using randomly split equal sets.

RESULTS

In those who reported presence of chronic pain (n = 2865), the prevalence of opioid use was 29% (95% CI:23.1%-35.6%). In adjusted models, participants with moderate and severe ADL disability had 1.6 (95% CI:1.13-2.32; P = 0.009) and 3.8 (95% CI: 1.80-7.90; P < 0.001) times higher odds of opioid consumption compared to no disability, respectively. Being female, alcohol consumption, higher pain intensity, history of dementia, fractures, and presence of ≥2 comorbidities were significantly associated with increased opioid use (P < 0.05).

CONCLUSION

Nearly one-third of the Brazilian elderly population experiencing chronic pain reported using opioids. The functional decline during the process of ageing appears to be a risk factor for pain intolerance and opioid use. Multidisciplinary approaches to detect early ADL disabilities and improve mobility and access to assistive technologies need to be established to prevent opioid overuse and addiction in elderly populations.

Integrated Approach to Chronic Pain-The Role of Psychosocial Factors and Multidisciplinary Treatment: A Narrative Review

BACKGROUND

Chronic non-malignant pain represents a growing global public health priority. Chronic pain is multifactorial, with numerous biological, psychological, and social factors contributing to this pain syndrome. It affects not only the patients, impairing their quality of life, but also their family and social environment. Chronic pain is a diagnosis and requires effective and sustainable treatment strategies.

OBJECTIVE

Our aim was to critically review the available evidence on the importance of different approaches in treating patients with chronic non-malignant pain, emphasizing the effectiveness of integrating psychological and social factors within a multidisciplinary framework.

METHODS

This was a non-systematic narrative review of the basic and recent literature analyzing approaches to the treatment of chronic non-malignant pain. The inclusion criteria for the papers were chronic non-malignant pain, treatment approach, review, and original research papers published in English in the last five years (PubMed search), and the basic literature was selected from the references of new papers according to the knowledge and experience of the authors.

RESULTS

This literature review included 120 papers, of which 83 were basic, and 37 were new, published in the last 5 years (2018-2023). The results show that both the basic and newly published literature advocate for a biopsychosocial approach to treating chronic pain.

CONCLUSIONS

New findings, compared to the earlier literature, indicate a new classification of chronic pain into primary and secondary. Chronic pain should be approached with a biopsychosocial model within a multidisciplinary treatment framework. This model addresses the complex interplay of biological, psychological, and social factors, offering a holistic strategy for effective pain management.

Trends in Physiotherapy of Chronic Low Back Pain Research: Knowledge Synthesis Based on Bibliometric Analysis

BACKGROUND

Physiotherapy and chronic low back pain (CLBP) form a broad and quickly developing research area. The aim of this article was to holistically, thematically and chronologically analyze and synthesize the literature production in this research area and identify the most prolific research entities and research themes.

METHODS

This article quantitatively and qualitatively analyzed research literature production harvested from the Scopus bibliometric database, using a triangulation of bibliometric and thematic analysis. For this, Excel 2024, Bibliometrix Biblioshiny 4.1 and VOSviewer version 1.6.20 softwares were used.

RESULTS

In the Scopus database, 2843 data sources were found, which were published between 1974 and 26 February 2024. The growth trend has been linearly positive since the beginning of publication, and after 2018 exponential growth began. A review of the most prolific entities showed that the most literature was published in America, Europe and Australasia. The thematic analysis of the information sources identified six main themes (pathophysiology of CLBP and the quantification assessment tools, diagnostics and CLBP treatment, CLBP questionnaires and surveys, quality of life, complementary methods in physiotherapy and psychosocioeconomic aspects), while the chronological analysis revealed three main areas of development: assessment tools, CLBP processing and study methodology.

CONCLUSIONS

The results of this bibliometric study present a good starting point for further research, providing taxonomy and research landscapes as a holistic framework offering multidisciplinary knowledge about CLBP, while chronological analysis provides a basis for identifying prospective research trends. This article offers an interdisciplinary view of the current issue of public health. The results of this study provide a basis for the development of both the physiotherapy and epidemiological fields.

Questionnaires assessing knowledge and beliefs about musculoskeletal conditions are potentially suitable for use, but further research is needed: a systematic review

OBJECTIVES

To evaluate the measurement properties of Patient-reported outcome measures (PROMs) for knowledge and/or beliefs about musculoskeletal conditions.

STUDY DESIGN AND SETTING

A systematic review was performed according to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines. This review was prospectively registered on PROSPERO - ID: CRD42022303111. Electronic databases, reference lists, forward citation tracking, and contact with experts were used to identify studies. Eligible studies were reports developing or assessing a measurement property of a PROM measuring musculoskeletal condition specific-knowledge and/or beliefs. We assessed the methodological quality and measurement properties of included studies. A modified Grading of Recommendations Assessment Development and Evaluation approach was used to rate the quality of evidence for each PROM.

RESULTS

The literature search was performed from inception to 11th September 2023. Sixty records were included, reporting 290 individual studies, and provided information on 25 PROMs. Five PROMs presented sufficient structural validity, three presented sufficient cross-cultural validity, ten presented sufficient reliability, three presented sufficient criterion validity, six presented sufficient hypothesis-testing, and four presented sufficient responsiveness. No PROM presented sufficient evidence for content validity, internal consistency, and measurement error. Based on the available evidence, no PROM was classified as suitable for use according to the COSMIN recommendations. Twenty-four PROMs are potentially suitable for use, and one PROM is not recommended for use.

CONCLUSION

No PROM designed to assess knowledge and/or beliefs about musculoskeletal conditions meets the COSMIN criteria of suitable for use. Most PROMs identified in this systematic review were considered as potentially suitable for use and need further high-quality research to assess their measurement properties.

The Role and Applications of Artificial Intelligence in the Treatment of Chronic Pain

PURPOSE OF REVIEW

This review aims to explore the interface between artificial intelligence (AI) and chronic pain, seeking to identify areas of focus for enhancing current treatments and yielding novel therapies.

RECENT FINDINGS

In the United States, the prevalence of chronic pain is estimated to be upwards of 40%. Its impact extends to increased healthcare costs, reduced economic productivity, and strain on healthcare resources. Addressing this condition is particularly challenging due to its complexity and the significant variability in how patients respond to treatment. Current options often struggle to provide long-term relief, with their benefits rarely outweighing the risks, such as dependency or other side effects. Currently, AI has impacted four key areas of chronic pain treatment and research: (1) predicting outcomes based on clinical information; (2) extracting features from text, specifically clinical notes; (3) modeling 'omic data to identify meaningful patient subgroups with potential for personalized treatments and improved understanding of disease processes; and (4) disentangling complex neuronal signals responsible for pain, which current therapies attempt to modulate. As AI advances, leveraging state-of-the-art architectures will be essential for improving chronic pain treatment. Current efforts aim to extract meaningful representations from complex data, paving the way for personalized medicine. The identification of unique patient subgroups should reveal targets for tailored chronic pain treatments. Moreover, enhancing current treatment approaches is achievable by gaining a more profound understanding of patient physiology and responses. This can be realized by leveraging AI on the increasing volume of data linked to chronic pain.

Enkephalins and Pain Modulation: Mechanisms of Action and Therapeutic Perspectives

Enkephalins, a subclass of endogenous opioid peptides, play a pivotal role in pain modulation. Enkephalins primarily exert their effects through opioid receptors located widely throughout both the central and peripheral nervous systems. This review will explore the mechanisms by which enkephalins produce analgesia, emotional regulation, neuroprotection, and other physiological effects. Furthermore, this review will analyze the involvement of enkephalins in the modulation of different pathologies characterized by severe pain. Understanding the complex role of enkephalins in pain processing provides valuable insight into potential therapeutic strategies for managing pain disorders.

Comparison of Short-Term Effects of Different Spinal Manipulations in Patients with Chronic Non-Specific Neck Pain: A Randomized Controlled Trial

Spinal manipulations for chronic non-specific neck pain (CNNP) include cervical, cervicothoracic junction, and thoracic spine (CCT) manipulations as well as upper cervical spine (UCS) manipulations. This study aimed to compare the short-term effects of UCS manipulation versus a combination of CCT spine manipulations on pain intensity, disability, and cervical range of motion (CROM) in CNNP patients. In a private physiotherapy clinic, 186 participants with CNNP were randomly assigned to either the UCS (n = 93) or CCT (n = 93) manipulation groups. Neck pain, disability, and CROM were measured before and one week after the intervention. No significant differences were found between the groups regarding pain intensity and CROM. However, there was a statistically significant difference in neck disability, with the CCT group showing a slightly greater decrease (CCT: 16.9 ± 3.8 vs. UCS: 19.5 ± 6.8; p = 0.01). The findings suggest that a combination of manipulations in the CCT spine results in a slightly more pronounced decrease in self-perceived disability compared to UCS manipulation in patients with CNNP after one week. However, no statistically significant differences were observed between the groups in terms of pain intensity or CROM.

A review of prospective studies regarding percutaneous peripheral nerve stimulation treatment in the management of chronic pain

Conventionally, peripheral nerve stimulation (PNS) for treatment of chronic pain has involved a two-stage process: a short-term (e.g., 7 days) trial and, if significant pain relief is achieved, a permanent PNS system is implanted. A percutaneous PNS treatment is now available where a coiled lead may be implanted for up to 60 days with the goal of producing sustained relief. In the present review, published prospective trials using percutaneous PNS treatment were identified and synthesized. The collected evidence indicates that percutaneous PNS treatment for up to 60 days provides durable clinically significant improvements in pain and pain interference. Similar efficacy across diverse targets and etiologies supports the broad applicability for use within the chronic pain population using this nonopioid technology.

Pain management in victims of disasters

Pain is widely studied and is considered a major clinical, social, and economic problem worldwide, although it remains poorly understood. For disaster victims, the complex picture, biologically, psychologically, and socially, only makes the situation even more complicated. This narrative review aims to describe specific aspects of pain and pain management in disaster victims. We reviewed relevant literature, both on pain management and selected specific data related to conflict victims. We discuss the complexity of the picture, its different aspects, and mechanisms. We discuss the limitations of current approaches and propose a simple strategy, including mitigation plans, all illustrated by a case study based on a personal experience in the Gaza Strip in 2022. The vulnerability factors are well known, as well as the tangle of intense acute pain and the persistence of pain in the subacute and chronic phase. However, the management of acute pain is, in a disaster context, more constrained than chosen. Empirical evidence suggests a focus on modifiable risk factors as well as the evaluation of strategies guiding future management. This management may depend on obstacles and barriers, linked to the context of the disaster, the availability of medicines, techniques, skills as well as linguistic and cultural barriers. Our proposal includes systematic assessment and, in a later phase, tailored and personalized treatment. In the chronic phase of rehabilitation and follow-ups, the essential place for management of psychological and social aspects become predominant. In disaster areas, including during and after conflict, the management, and recommendations for the management of acute and chronic pain are complex, distinct but interdependent. Acute pain must be systematically assessed and treated while personalized care pathways are desirable at a later stage. Psychological and social considerations are essential. Data collection should be systematically considered.

Effects of proactive healthcare on pain, physical and activities of daily living functioning in vulnerable older adults with chronic pain: a pragmatic clinical trial with one- and two-year follow-up

PURPOSE

To investigate the changes in pain, physical and activities of daily living (ADL) functioning in vulnerable older adults with chronic pain after proactive primary care intervention.

METHODS

This study was embedded in a prospective, pragmatic, matched-control multicenter trial at 19 primary care practices in Sweden, with proactive medical and social care (Intervention Group, IG, n = 134) in comparison with usual care (Control Group, CG, n = 121). Patients with chronic pain, defined as pain experienced longer than 3 months, were included in this subgroup analysis. Data on pain aspects, physical and ADL functioning were collected in the questionnaires at baseline, one- and two-year follow-up (FU-1 and FU-2). Data on prescribed pain medications was collected by local health authorities.

RESULTS

Mean age was 83.0 ± 4.7 years with almost equal representation of both genders. From baseline until FU-2, there were no significant within-group or between-group changes in pain intensity. Small adjustments of pain medication prescriptions were made in both groups. Compared to FU-1, the functional changes were more measurable at FU-2 as fewer participants had impaired physical functioning in IG (48.4%) in comparison to CG (62.6%, p = 0.027, Effect Size φ = 0.14). Higher scores of ADL-staircase (more dependent) were found in both groups (p < 0.01, Effect Size r = 0.24 in CG and r = 0.16 in IG).

CONCLUSION

Vulnerable older adults with chronic pain seemed to remain physical and ADL functioning after proactive primary care intervention, but they may need tailored strategies of pain management to improve therapeutic effects.

TRIAL REGISTRATION

ClinicalTrials.gov 170608, ID: NCT03180606.

Transcriptomic signature, bioactivity and safety of a non-hepatotoxic analgesic generating AM404 in the midbrain PAG region

Safe and effective pain management is a critical healthcare and societal need. The potential for acute liver injury from paracetamol (ApAP) overdose; nephrotoxicity and gastrointestinal damage from chronic non-steroidal anti-inflammatory drug (NSAID) use; and opioids' addiction are unresolved challenges. We developed SRP-001, a non-opioid and non-hepatotoxic small molecule that, unlike ApAP, does not produce the hepatotoxic metabolite N-acetyl-p-benzoquinone-imine (NAPQI) and preserves hepatic tight junction integrity at high doses. CD-1 mice exposed to SRP-001 showed no mortality, unlike a 70% mortality observed with increasing equimolar doses of ApAP within 72 h. SRP-001 and ApAP have comparable antinociceptive effects, including the complete Freund's adjuvant-induced inflammatory von Frey model. Both induce analgesia via N-arachidonoylphenolamine (AM404) formation in the midbrain periaqueductal grey (PAG) nociception region, with SRP-001 generating higher amounts of AM404 than ApAP. Single-cell transcriptomics of PAG uncovered that SRP-001 and ApAP also share modulation of pain-related gene expression and cell signaling pathways/networks, including endocannabinoid signaling, genes pertaining to mechanical nociception, and fatty acid amide hydrolase (FAAH). Both regulate the expression of key genes encoding FAAH, 2-arachidonoylglycerol (2-AG), cannabinoid receptor 1 (CNR1), CNR2, transient receptor potential vanilloid type 4 (TRPV4), and voltage-gated Ca2+ channel. Phase 1 trial (NCT05484414) (02/08/2022) demonstrates SRP-001's safety, tolerability, and favorable pharmacokinetics, including a half-life from 4.9 to 9.8 h. Given its non-hepatotoxicity and clinically validated analgesic mechanisms, SRP-001 offers a promising alternative to ApAP, NSAIDs, and opioids for safer pain treatment.

Association between the dietary inflammatory index and pain in US adults from NHANES

OBJECTIVES

The growing global burden of pain is gradually expanding from the medical field to public health. Dietary inflammatory potential correlates with inflammatory markers, and inflammation is one of the main mechanisms of pain.

METHODS

This study explored the association between dietary inflammatory index (DII) and pain from the NHANES database on DII and pain (neck pain, low back pain, joint pain, and headache or migraine) using logistic regression and stratified analysis.

RESULTS

The results show a stronger association between DII and joint pain (Q4 of DII adjusted-OR = 1.23, 95% CI = 1.08-1.40, P = 0.003) and headache or migraine (Q4 of DII adjusted-OR = 1.31, 95% CI = 1.15-1.48, P < 0.001), but no association is found in neck pain (Q4 of DII adjusted-OR = 1.03, 95% CI = 0.89-1.20, P = 0.65) and low back pain (Q4 of DII adjusted-OR = 1.04, 95% CI = 0.92-1.17, P = 0.54). After stratifying the data according to demographics, differences in the relationship between DII and pain are found at different levels of the population.

DISCUSSION

This study identifies high DII as a risk factor for joint pain and headache or migraine.

Burden of neck pain in general population of China, 1990-2019: An analysis for the Global Burden of Disease Study 2019

Background

Neck pain has become very common in China and has greatly affected individuals, families, and society in general. In this study, we aimed to report on the rates and trends of the prevalence, incidence, and years lived with disability (YLDs) caused by neck pain in the general population of China from 1990 to 2019.

Methods

We used data from the Global Burden of Diseases, Injuries, and Risk Factors Study 2019 (GBD 2019) study to estimate the number and age standardised rates per 100 000 population of neck pain point prevalence, annual incidence, and YLDs in 33 provinces/municipalities/autonomous regions of China, stratified by age, sex, and sociodemographic index (SDI) from 1990 to 2019. We then compared these estimates with other G20 countries.

Results

There were 6.80 × 107 patients with neck pain in 2019, presenting an increase from 3.79 × 107 in 1990. Likewise, the national age-standardised point prevalence increased slightly from 3.53% in 1990 to 3.57% in 2019. The YLDs increased by 78.08%, from 3814 × 103 in 1990 to 6792 × 103 in 2019. The age-standardised YLDs rate increased 1.50% from 352.84 in 1990 to 358.10 in 2019. The point prevalence of neck pain in 2019 was higher in females compared with males. These estimates were all above the global average level and increased more rapidly among G20 countries from 1990 to 2019. We generally observed a positive association between age-standardised YLD rates for neck pain and SDI, suggesting the burden is higher at higher sociodemographic indices.

Conclusions

Neck pain is a serious public health problem in the general population in China, especially in its central and western regions, with an overall increasing trend in the last three decades. This is possibly related to changes of people's lifestyles and work patterns due to improvements in societal well-being and technology. Raising awareness of risk factors for neck pain in the general population and establishing effective preventive and treatment strategies could help reduce the future burden of neck disorders.

Variables associated with nonresponders to high-frequency (10 kHz) spinal cord stimulation

INTRODUCTION

The use of spinal cord stimulation (SCS) therapy to treat chronic pain continues to rise. Optimal patient selection remains one of the most important factors for SCS success. However, despite increased utilization and the existence of general indications, predicting which patients will benefit from neuromodulation remains one of the main challenges for this therapy. Therefore, this study aims to identify the variables that may correlate with nonresponders to high-frequency (10 kHz) SCS to distinguish the subset of patients less likely to benefit from this intervention.

MATERIALS AND METHODS

This was a retrospective single-center observational study of patients who underwent 10 kHz SCS implant. Patients were divided into nonresponders and responders groups. Demographic data and clinical outcomes were collected at baseline and statistical analysis was performed for all continuous and categorical variables between the two groups to calculate statistically significant differences.

RESULTS

The study population comprised of 237 patients, of which 67.51% were responders and 32.49% were nonresponders. There was a statistically significant difference of high levels of kinesiophobia, high self-perceived disability, greater pain intensity, and clinically relevant pain catastrophizing at baseline in the nonresponders compared to the responders. A few variables deemed potentially relevant, such as age, gender, history of spinal surgery, diabetes, alcohol use, tobacco use, psychiatric illness, and opioid utilization at baseline were not statistically significant.

CONCLUSION

Our study is the first in the neuromodulation literature to raise awareness to the association of high levels of kinesiophobia preoperatively in nonresponders to 10 kHz SCS therapy. We also found statistically significant differences with greater pain intensity, higher self-perceived disability, and clinically relevant pain catastrophizing at baseline in the nonresponders relative to responders. It may be appropriate to screen for these factors preoperatively to identify patients who are less likely to respond to SCS. If these modifiable risk factors are present, it might be prudent to consider a pre-rehabilitation program with pain neuroscience education to address these factors prior to SCS therapy, to enhance successful outcomes in neuromodulation.

Update on Musculoskeletal Pain Management

Pain is the most common complaint reported to orthopedists in the outpatient clinic, emergency room, or booth. Numerous publications report the inadequate management of both acute and chronic pain by health professionals. This updated article aims to provide information about musculoskeletal pain, its classification, evaluation, diagnosis, and the multimodal therapeutic approach for each case. For acute pain, adequate control allows for earlier rehabilitation to work and reduces the rates of pain chronification. For chronic pain, the goal is to reduce its intensity and improve the quality of life. Currently, some procedures are increasingly used and aided by imaging tests for diagnostic and therapeutic purposes.

Effectiveness of diagnosis and treatment based on movement system impairment in individuals with cervical pain: A randomized controlled trial

BACKGROUND

Movement System Impairment (MSI) classification and treatment effectively diagnose and treat the individual with neck pain. There is a lacuna in the current neck pain management guidelines addressing movement-specific mechanical diagnosis. MSI is based on the movement-specific mechanical diagnosis and kinesiopathologic model.

PURPOSE

The present study aimed to investigate the effectiveness of the movement system impairment model among neck pain individuals.

METHODS

This study was designed as a randomized controlled trial. Eighty-two participants were screened for eligibility; Sixty individuals fulfilling the inclusion criteria were randomized into the experimental group (n = 30) and control group (n = 30). A total of 52 individuals completed the study, 26 in both groups. The experimental and the control group received treatment as recommended by the MSI model and clinical practice guideline (CPG) for neck pain with mobility deficits. All participants were assessed for pain intensity, cervical range of motion, deep cervical muscle strength, endurance, and disability at baseline and the end of 3rd week of treatment.

RESULTS

Significant differences were found in pain intensity, cervical range of motion, cervical muscle strength, endurance, and disability with both groups at the end of 10 sessions of treatment spread over three weeks (p < 0.05). However, the experimental group (MSI) demonstrated more clinical benefits than CPG based neck mobility deficits treatment.

CONCLUSION

The movement system impairment model may effectively diagnose and treat neck pain in individuals with mobility deficits. Future research is warranted to establish its long-term effect.

The epidemiology of neck and low back pain in Iran: a national and sub-national analysis from 1990 to 2019

Background

Neck pain (NP) is a condition influenced by multiple factors. It places a significant burden on individuals suffering from NP and on social and economic systems. On a global scale, low back pain (LBP) stands out as a significant contributor to years lost to disability, and this burden is on the rise due to population growth and aging.

Methods

The Global Burden of Disease database was used to collect data on the prevalence, incidence, and years lived with disability (YLD) of NP and LBP between 1990 and 2019. Various factors, including age group, gender, Iran, and its 31 provinces, were used to classify the data.

Results

Iran accounted for 0.86 million incident cases of NP in 2019, with age-standardized incident rate per 100 000 population of 934.1. Tehran has the maximum age-standardized prevalence, incidence, and YLD. Iran accounted for the age-standardized incidence rate for LBP per 100 000 population of 3492.9, and it reduced to -8.35% from 1990. Mazandaran exhibits the highest levels of prevalence, incidence, and YLD for LBP in 2019. In Iran, the point prevalence of NP in 2019 was higher in females and increased with age up to 50-54 years for females and 70-74 years for males. However, there is only a slight difference between females and males in Iran regarding LBP prevalence.

Conclusions

In this study, the authors report the prevalence, incidence, YLD, and age-standardized rates for NP and LBP in the world's general population and Iran's population based on its sub-nations in 1990 and 2019.

Evaluation of methodological and reporting quality of systematic reviews on conservative non-pharmacological musculoskeletal pain management in children and adolescents: A methodological analysis

BACKGROUND

There are no studies investigating the methodological and report quality of systematic reviews of non-pharmacological interventions for musculoskeletal pain management among children and adolescents.

OBJECTIVE

To evaluate the methodological and reporting quality of systematic reviews on conservative non-pharmacological pain management in children and adolescents with musculoskeletal pain.

METHODS

Searches were conducted on the Cochrane Database of Systematic Reviews, Medline, Embase, and three other databases. Two pairs of reviewers independently assessed each article according to the predetermined selection criteria. We assessed the methodological quality of systematic reviews, using the AMSTAR 2 checklist and the quality of reporting, using PRISMA checklist. Descriptive analysis was used to summarise the characteristics of all included systematic reviews. The percentage of systematic reviews achieving each item from the AMSTAR 2, PRISMA checklist and the overall confidence in the results were described.

RESULTS

We included 17 systematic reviews of conservative non-pharmacological pain management for musculoskeletal pain in children and adolescents. Of the 17 systematic reviews included, nine (53%) were rated as "critically low", seven (41%) were rated as "low", and one (6%) was rated as "high" methodological quality by AMSTAR-2. The reporting quality by items from PRISMA range from 17.6% (95% CI 6.2 to 41) to 100% (95% CI 81.6 to 100).

CONCLUSION

This systematic review of physical interventions in children and adolescents showed overall 'very low' to 'high' methodological quality and usually poor reporting quality.

CT-Guided Radiofrequency Ablation Targeting the Herniation Edge of the Cervical Disc for the Treatment of Neck Pain: A Retrospective Study

INTRODUCTION

Sinuvertebral nerve overactivation is one of the mechanisms of neck pain caused by cervical disc herniation. Radiofrequency ablation (RFA) of sinuvertebral nerves has shown efficacy for the treatment of discogenic low back pain. However, relatively few studies evaluated the efficacy of RFA of sinuvertebral nerves for the treatment of chronic neck pain caused by cervical disc herniation.

METHODS

Clinical data were retrospectively collected from 168 patients diagnosed with cervical disc herniated neck pain from January 1, 2019, to September 1, 2022, who were treated with computed tomography (CT)-guided cervical disc RFA of at the Pain Medicine Center of Zhejiang Provincial People's Hospital. A 22-G RFA needle (Inomed, Emmendingen, Germany) was inserted between the carotid artery and trachea to the intervertebral disc under the direction of CT the scanner. Depending on the position of the protruding nucleus pulposus or the rupture of the annulus fibrosus, the needle was inserted into the posterior side of the intervertebral disc until the tip of the needle reached the target position. The numeric rating scale (NRS) score, pain relief and appearance of complications after RFA were evaluated.

RESULTS

A total of 168 patients underwent CT-guided RFA for cervical disc herniation. The average duration of pain was 67.07 ± 70.42 months. At 6 months of follow-up, the median preoperative NRS score decreased significantly from preoperative 5.41 ± 1.08 to postoperative 1.341 ± 1.25 at 1 month, 1.4 ± 1.38 at 3 months and 1.72 ± 1.41 at 6 months after RFA (p < 0.01). The numbers of patients with ≥ 50% of their neck pain relieved were 84% (141/168), 87% (147/168), 87% (147/168) and 79% (133/168) at 1 day, 1 month, 3 months and 6 months after RFA, respectively. No serious complications related to treatment or long-term complications were observed.

CONCLUSIONS

This study highlights that CT-guided RFA targeting the edge of cervical disc herniation to destroy the sinuvertebral nerves can effectively relieve neck pain, and the computed tomography (CT)-guided RFA treatment strategy has the advantages of having few complications.

Does brain entrainment using binaural auditory beats affect pain perception in acute and chronic pain?: a systematic review

BACKGROUND

Pain is a major clinical problem across all ages with serious social and economic consequences and a great negative impact on quality of life. Brain entrainment using binaural beats is a non-pharmaceutical intervention that is claimed to have analgesic effects in acute and chronic pain. We aimed to systematically review the available randomized clinical trials on the efficacy of binaural auditory beats in reducing adults' pain perception in acute and chronic pain. A systematic search in electronic databases including Medline (via PubMed), Web of Science, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase was performed. The search was completed through Google Scholar and a manual search of the reference lists of all included studies. Randomized clinical trials with full text available in English that investigated the effect of binaural auditory beats on pain perception in acute and chronic pain in adults were included. The risk of bias was assessed by the revised Cochrane risk-of-bias (RoB 2) tool. Furthermore, The GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach was used to assess the quality of the evidence. Sixteen studies (three on chronic pain and thirteen on acute pain perception) fulfilled the eligibility criteria. Because of substantial heterogeneity of the studies, a meta-analysis was inappropriate and this review focused on the narrative interpretation of the results. The risk of bias in most studies was high and the quality of evidence was low to very low. Although the effects of binaural beats on pain perception seem to be influenced by the etiology of pain or medical procedures, our review identifies alpha or a combination of tones in the range of delta to alpha as a potential non-pharmacological intervention in reducing acute pain. However, drawing a conclusion regarding the efficacy of binaural beats for chronic pain requires more high-quality studies.

REGISTRATION

The protocol of this review was registered in PROSPERO (No. CRD42023425091).

A qualitative longitudinal study of traumatic orthopaedic injury survivors' experiences with pain and the long-term recovery trajectory

OBJECTIVES

To explore trauma patients' experiences of the long-term recovery pathway during 18 months following hospital discharge.

DESIGN

Longitudinal qualitative study.

SETTING AND PARTICIPANTS

Thirteen trauma patients with injuries associated with pain that had been interviewed 6 weeks after discharge from Oslo University Hospital in Norway, were followed up with an interview 18 months postdischarge.

METHOD

The illness trajectory framework informed the data collection, with semistructured, in-depth interviews that were analysed thematically.

RESULTS

Compared with the subacute phase 6 weeks postdischarge, several participants reported exacerbated mental and physical health, including increased pain during 18 months following discharge. This, andalternating periods of deteriorated health status during recovery, made the pathway unpredictable. At 18 months post-discharge, participants were coping with experiences of reduced mental and physical health and socioeconomic losses. Three main themes were identified: (1) coping with persistent pain and reduced physical function, (2) experiencing mental distress without access to mental healthcare and (3) unmet needs for follow-up care. Moreover, at 18 months postdischarge, prescribed opioids were found to be easily accessible from GPs. In addition to relieving chronic pain, motivations to use opioids were to induce sleep, reduce withdrawal symptoms and relieve mental distress.

CONCLUSIONS AND IMPLICATIONS

The patients' experiences from this study establish knowledge of several challenges in the trauma population's recovery trajectories, which may imply that subacute health status is a poor predictor of long-term outcomes. Throughout recovery, the participants struggled with physical and mental health needs without being met by the healthcare system. Therefore, it is necessary to provide long-term follow-up of trauma patients' health status in the specialist health service based on individual needs. Additionally, to prevent long-term opioid use beyond the subacute phase, there is a need to systematically follow-up and reassess motivations and indications for continued use throughout the recovery pathway.

Studies on Pain Associated with Anxiety or Depression in the Last 10 Years: A Bibliometric Analysis

Background

The prevalence of pain comorbid and anxiety/depression in clinical observations has been high, and the number of related publications has increased in recent years. Nevertheless, few studies have used bibliometric methods to analyze the scientific research on comorbid pain and depression/anxiety. The aim of this study was to systematically examine the trends in global scientific research on comorbid pain and depression/anxiety from 2012 to 2022.

Methods

Papers published between 2012 and 2022 were identified in the Web of Science database. Publications that examined comorbid pain and depression/anxiety were included. The language was limited to English. CiteSpace, Excel and VOSviewer were used to analyze the volume of publications, countries, institutions, authors, cocited authors, and keywords.

Results

A total of 30,290 papers met the inclusion criteria of the study. Using CiteSpace, VOSviewer and Excel, the results showed that the United States (10,614 publications), Harvard University (1195 publications), and Jensen, Mark P. (77 publications) were the most productive country, institution, and author, respectively. The hotspots and frontiers were "relationship between depression and pain", "gender differences in pain and depression/anxiety domains", "study of specific pain types with depression/anxiety", "treatment of pain combined with anxiety/depression", and "effects of COVID-19 on patients with pain combined with depression/anxiety".

Conclusion

These findings indicate a growing interest in the field of comorbid pain and depression/anxiety. The research has been broad and deep, but there is still much room for growth. Furthermore, there is a need for more mature global collaborative networks as well as more high-quality research results in the future.

Clinical validation of grouping conservative treatments in neck pain for use in a network meta-analysis: a Delphi consensus study

BACKGROUND

A network meta-analysis aims to help clinicians make clinical decisions on the most effective treatment for a certain condition. Neck pain is multifactorial, with various classification systems and treatment options. Classifying patients and grouping interventions in clinically relevant treatment nodes for a NMA is essential, but this process is poorly defined.

OBJECTIVE

Our aim is to obtain consensus among experts on neck pain classifications and the grouping of interventions into nodes for a future network meta-analysis.

DESIGN

A Delphi consensus study involving neck pain experts worldwide.

METHODS

We invited authors of neck pain clinical practice guidelines published from 2014 onwards. The Delphi baseline questionnaire was developed based on the findings of a scoping review, including four items on classifications and 19 nodes. Participants were asked to record their level of agreement on a seven-point Likert scale or using Yes/No/Not sure answer options for the various statements. We used descriptive analysis to summarise the responses on each statement with content analysis of the free-text comments.

RESULTS

In total, 18/80 experts (22.5%) agreed to participate in one or more Delphi rounds. We needed three rounds to reach consensus for two classification of neck pain: one based on aetiology and one on duration. In addition, we also reached consensus on the grouping of interventions, including a definition of each node, with the number of nodes reduced to 17.

CONCLUSION

With this consensus we clinically validated two neck pain classifications and grouped conservative treatments into 17 well-defined and clinically relevant nodes.

Transcutaneous Electric Nerve Stimulation in Animal Model Studies: From Neural Mechanisms to Biological Effects for Analgesia

OBJECTIVE

This systematic and meta-analysis review evaluated the transcutaneous electrical nerve stimulation (TENS)-induced action mechanisms for animal analgesia.

MATERIALS AND METHODS

Two independent investigators identified relevant articles published until February 2021 through a literature review, and a random-effects meta-analysis was performed to synthesize the results.

RESULTS

Of the 6984 studies found in the data base search, 53 full-text articles were selected and used in the systematic review. Most studies used Sprague Dawley rats (66.03%). High-frequency TENS was applied to at least one group in 47 studies, and most applications were performed for 20 minutes (64.15%). Mechanical hyperalgesia was analyzed as the primary outcome in 52.83% of the studies and thermal hyperalgesia in 23.07% of studies using a heated surface. More than 50% of the studies showed a low risk of bias on allocation concealment, random housing, selective outcome reporting, and acclimatization before the behavioral tests. Blinding was not performed in only one study and random outcome assessment in another study; acclimatization before the behavioral tests was not performed in just one study. Many studies had an uncertain risk of bias. Meta-analyses indicated no difference between low-frequency and high-frequency TENS with variations among the pain models.

CONCLUSIONS

This systematic review and meta-analysis suggests that TENS has presented a substantial scientific foundation for its hypoalgesic effect in preclinical studies for analgesia.

Obesity and the risk of multiple or severe frequent knee pain episodes: a 4-year follow-up of the ELSA-Brasil MSK cohort

BACKGROUND/OBJECTIVE

Knee pain is an important health problem due to its high prevalence, negative impact on daily activities and quality of life, and societal burden. While the link between excess weight and knee pain has been well-documented in the literature, many studies are limited to patients with osteoarthritis or use cross-sectional data. This longitudinal study investigated whether overweight and obesity were associated with the frequency and severity of frequent knee pain (FKP) episodes over 4 years in civil servants enrolled in the ELSA-Brasil MSK cohort.

METHODS

Knee pain was assessed during baseline face-to-face interviews (2012-2014) and four yearly telephone follow-ups (2015-2019). Disabling FKP episodes or those of moderate to very severe intensity were classified as severe. Multinomial logistic regression models adjusted for confounders were used to test for associations in two participant groups: those with knee pain at baseline (prognosis cohort) and those without knee pain (incidence cohort).

RESULTS

A total of 2644 participants were included: 54.2% female, mean age 55.8 (SD 8.8) years. In the incidence cohort (n = 1896), obesity increased the risk of one (OR: 1.63; 95% CI 1.13-2.37) and multiple FKP episodes (OR: 2.61; 95% CI 1.71-3.97), as well as the risk of non-severe (OR: 1.72; 95% CI 1.04-2.84) and severe FKP episodes (OR: 2.10; 95% CI 1.50-2.95). In the prognosis cohort (n = 748), obesity increased the risk of multiple (OR: 2.54; 95% CI 1.60-4.05) and severe FKP episodes (OR: 2.31; 95% CI 1.49-3.59). Overweight presented the same trends but fell short of significance.

CONCLUSIONS

These results provide further support that overweight and obesity are important contributors to the incidence and worsening of FKP, and that weight management must be prioritized in multidisciplinary knee pain prevention and treatment programs to reduce the burden of musculoskeletal disorders.

Correlation of Positive Psychological Health among US Adults (Aged ≥ 50 Years) with Pain and Documented Opioid Treatment

In this study, we aimed to identify the factors correlated with positive psychological health among United States older adults (≥50 years) with pain and documented opioid treatment. This retrospective cross-sectional study utilized a nationally representative dataset (Medical Expenditure Panel Survey). A multivariable logistic regression model was developed to assess the correlation of positive psychological health in the eligible population. The logistic regression model showed having excellent/very good/good (versus fair/poor) perceived health (adjusted odds ratio [AOR] = 9.062; 95% confidence interval [CI] = 5.383, 15.254) had a statistically significant correlation with positive psychological health among the eligible population. This finding offers important insights for clinicians and policymakers to consider when formulating approaches to better manage the psychological health of United States older adults with pain and documented opioid treatment.

An economic evaluation of pharmacopuncture versus usual care for chronic neck pain: a pragmatic randomized controlled trial

BACKGROUND

This study aimed to evaluate the cost utility of pharmacopuncture in comparison with usual care for patients with chronic neck pain.

METHODS

A 12-week, multicenter, pragmatic randomized controlled trial was conducted, and 101 patients suffering from chronic neck pain for more than six months were randomly placed into the pharmacopuncture and usual care groups to receive four weeks of treatment and 12 weeks of follow-up observations. The quality-adjusted life year (QALY) was calculated using EQ-5D and SF-6D. Concerning costs in 2019, a primary analysis was performed on societal perspective cost, and an additional analysis was performed on healthcare perspective cost.

RESULTS

Compared to usual care, pharmacopuncture was superior as it showed a slightly higher QALY and a lower incremental cost of $1,157 from a societal perspective. The probability that pharmacopuncture would be more cost-effective at a willingness-to-pay (WTP) of $26,374 was 100%. Pharmacopuncture was also superior from a healthcare perspective, with a lower incremental cost of $26. The probability that pharmacopuncture would be more cost-effective at a WTP of $26,374 was 83.7%.

CONCLUSIONS

Overall, pharmacopuncture for chronic neck pain was found to be more cost-effective compared to usual care, implying that clinicians and policy makers should consider new treatment options for neck pain.

TRIAL REGISTRATION

Number NCT04035018 (29/07/2019) Clinicaltrials.gov; Number KCT0004243 (26/08/2019) Clinical Research Information Service.

The composition, pharmacological effects, related mechanisms and drug delivery of alkaloids from Corydalis yanhusuo

Corydalis yanhusuo W. T. Wang, also known as yanhusuo, yuanhu, yanhu and xuanhu, is one of the herb components of many Chinese Traditional Medicine prescriptions such as Jin Ling Zi San and Yuanhu-Zhitong priscription. C. yanhusuo was traditionally used to relieve pain and motivate blood and Qi circulation. Now there has been growing interest in pharmacological effects of alkaloids, the main bioactive components of C. yanhusuo. Eighty-four alkaloids isolated from C. yanhusuo are its important bioactive components and can be characterized into protoberberine alkaloids, aporphine alkaloids, opiate alkaloids and others and proper extraction or co-administration methods modulate their contents and efficacy. Alkaloids from C. yanhusuo have various pharmacological effects on the nervous system, cardiovascular system, cancer and others through multiple molecular mechanisms such as modulating neurotransmitters, ion channels, gut microbiota, HPA axis and signaling pathways and are potential treatments for many diseases. Plenty of novel drug delivery methods such as autologous red blood cells, self-microemulsifying drug delivery systems, nanoparticles and others have also been investigated to better exert the effects of alkaloids from C. yanhusuo. This review summarized the alkaloid components of C. yanhusuo, their pharmacological effects and mechanisms, and methods of drug delivery to lay a foundation for future investigations.

Educational needs and preferences of adult patients with acute or chronic pain: a mixed methods systematic review protocol

OBJECTIVES

This review will aim to synthesize the available quantitative and qualitative evidence on the educational needs and preferences of adult patients with acute or chronic pain.

INTRODUCTION

Acute and chronic pain are prevalent problems and are associated with significant individual and societal consequences. Education is a critical component of pain management. However, the impact of educational interventions on pain outcomes remains limited. The lack of patient input--what patients want to know and how they want to be informed--is one of the main issues underlying intervention design.

INCLUSION CRITERIA

We will include qualitative, quantitative, and mixed methods studies describing the educational needs and preferences of adult patients with acute or chronic pain.

METHODS

This review will follow the JBI guidelines for mixed methods systematic reviews. We will search MEDLINE (PubMed), Embase (Ovid), PsycINFO (Ovid), CINAHL (EBSCO), the Cochrane Central Register of Controlled Trials (CENTRAL), Web of Science, and ProQuest Dissertations and Theses. The search strategy will commence from the year 1990 onward and there will be no language restrictions. The retrieved titles, abstracts, and full-text reports will be screened by pairs of independent reviewers. These pairs of reviewers will also independently extract data using the JBI tools for mixed methods systematic reviews. Methodological quality will be assessed using the mixed methods appraisal tool. A convergent integrated approach to synthesis and integration of the quantitative and qualitative data will be used.

REVIEW REGISTRATION

PROSPERO CRD42022303834.

Analyzing facial action units in children to differentiate genuine and fake pain during inferior alveolar nerve block: a cross-sectional study

This study aimed to investigate the association between facial action units and pain levels in Syrian children, focusing on both genuine and fake pain expressions. A total of 300 Syrian children aged 6-9 years participated in the study. Pain levels were assessed using the validated Face, Legs, Activity, Cry, Consolability scale, and facial expressions were analyzed using the Facial Action Coding System. The children were asked to mimic their feelings after receiving a dental injection to elicit fake pain expressions. Statistical analysis, including multinomial logistic regression and chi-square tests, was conducted to determine the Action Units (AUs) associated with each pain level and to compare the differences between real and fake pain expressions. The results revealed significant associations between specific AUs and pain levels. For real pain expressions, the most activated AUs across different pain levels with positive coefficient values of correlation (P-value < 0.01) were analyzed. In contrast, for fake pain expressions, AU12 and AU38 were consistently observed to be the most activated. These findings suggest that certain AUs are uniquely associated with fake pain expressions, distinct from those observed in real pain expressions. Furthermore, there were no significant differences between boys and girls in terms of their genuine and fake pain expressions, indicating a similar pattern of AU activation (P-value > 0.05). It was concluded that AUs 4, 6, 41, and 46 were associated with mild pain, and AUs 4, 6, 41, 46, and 11 were associated with moderate pain cases. In severe pain, AUs 4, 6, 7, 9, 11, and 43 were associated. In fake pain feelings, AU43, AU38, and AU12 were the most activated with no difference between boys and girls.

In Vivo, In Vitro and In Silico Study of Cucurbita moschata Flower Extract: A Promising Source of Natural Analgesic, Anti-Inflammatory, and Antibacterial Agents

For thousands of years, medicinal plants have played a pivotal role in maintaining human health and improving the quality of human life. This study was designed to analyze the analgesic, anti-inflammatory, and antibacterial potentials of a hydro-methanolic extract of Cucurbita moschata flowers, along with qualitative and quantitative phytochemical screening. The anti-inflammatory effect was tested using the in vitro membrane stabilizing method for human red blood cells (HRBC), the analgesic effect was tested using the in vivo acetic acid-induced writing method, and the antibacterial effect was tested using the disc diffusion method. In silico ADME/T and molecular docking studies were performed to assess the potential of the stated phytochemicals against Cyclooxygenase-II enzyme. Phytochemical screening confirmed the presence of flavonoids, alkaloids, glycosides, tannins, and carbohydrates. The flower extract demonstrated the maximum protection of human red blood cells at 1000 µg/mL, with a 65.73% reduction in hemolysis in a hypotonic solution. The extract also showed significant (p < 0.05) and dose-dependent analgesic effects at oral doses of 200 and 400 mg/kg on the tested animals. Furthermore, the flower extract exhibited potent antibacterial activity due to the disc diffusion method, which was compared with standard ciprofloxacin. In silico testing revealed that 42 phytochemicals exhibited notable pharmacokinetic properties and passed drug likeness screening tests. Among the six best-selected compounds, 3,4-dihydro-2H-pyran-2-yl)methanamine showed the highest binding affinity (-10.1) with significant non-bonding interactions with the target enzyme. In conclusion, the hydro-methanolic extract of Cucurbita moschata was found to be rich in various phytochemicals that may be associated with therapeutic potential, and this study supports the traditional use of Cucurbita moschata flowers in the management of inflammation and painful conditions.