The Impact of Baseline Pain Intensity on the Effectiveness of Whole-Body Electromyostimulation (WB-EMS) for Nonspecific Chronic Back Pain.

INTRODUCTION: Recent clinical studies confirmed that whole-body electromyostimulation (WB-EMS) training is a safe and time-efficient therapeutic method for patients with nonspecific chronic back pain (NSCBP). However, significant variations in initial pain intensity among subjects in these studies have been observed. This study aims to determine if patients with differing initial pain intensities experience varying degrees of benefit from WB-EMS and to assess the overall correlation between initial pain levels and pain reduction. METHODS: Pain intensity datasets from two studies were combined. The pooled data included 121 NSCBP patients (38 males and 83 females) with an average age of 55.1 years (±11.8 years). Data was categorized by baseline pain intensity on the numeric rating scale (NRS) into seven groups: 0 to 2, >2 to 3, >3 to 4, >4 to 5, >5 to 6, >6 to 7, and >7. Both absolute and relative changes were analyzed. Additionally, a Spearman rho correlation test was performed on the entire dataset to evaluate the relationship between initial pain level and pain reduction. RESULTS: Significant improvements were noted across all NRS11 categories, with strong effect sizes (p) in all classes above 2, ranging from 0.56 to 0.90. The >7 category exhibited the highest rate of clinically significant changes (80%) and an average improvement of 3.72 points. The overall group from >1 to 10 showed an average improvement of 1.33 points, with 37% of the participants experiencing clinically significant improvements. The Spearman rho correlation test revealed a moderate positive relationship between initial pain level and pain reduction (r_s = 0.531, p < 0.001), indicating that, generally, higher initial pain levels are associated with greater pain reduction. CONCLUSION: The findings support the hypothesis that NSCBP patients with higher baseline NRS values benefit more substantially from WB-EMS. Those with NRS values above 7 show the greatest improvement and highest rate of clinical significance. The overall positive correlation between initial pain intensity and pain reduction further underscores the efficacy of WB-EMS in managing NSCBP across different pain intensities.

Alcohol Use Disorder and Chronic Pain: An Overlooked Epidemic.

Alcohol use disorder (AUD) and chronic pain disorders are pervasive, multifaceted medical conditions that often co-occur. However, their comorbidity is often overlooked, despite its prevalence and clinical relevance. Individuals with AUD are more likely to experience chronic pain than the general population. Conversely, individuals with chronic pain commonly alleviate their pain with alcohol, which may escalate into AUD. This narrative review discusses the intricate relationship between AUD and chronic pain. Based on the literature available, the authors present a theoretical model explaining the reciprocal relationship between AUD and chronic pain across alcohol intoxication and withdrawal. They propose that the use of alcohol for analgesia rapidly gives way to acute tolerance, triggering the need for higher levels of alcohol consumption. Attempts at abstinence lead to alcohol withdrawal syndrome and hyperalgesia, increasing the risk of relapse. Chronic neurobiological changes lead to preoccupation with pain and cravings for alcohol, further entrenching both conditions. To stimulate research in this area, the authors review methodologies to improve the assessment of pain in AUD studies, including self-report and psychophysical methods. Further, they discuss pharmacotherapies and psychotherapies that may target both conditions, potentially improving both AUD and chronic pain outcomes simultaneously. Finally, the authors emphasize the need to manage both conditions concurrently, and encourage both the scientific community and clinicians to ensure that these intertwined conditions are not overlooked given their clinical significance.

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

OBJECTIVES: To identify the patient-reported outcome measures (PROMs) used in clinical trials assessing interventions for chronic pain, describe their psychometric properties, and the clinical domains they cover. STUDY DESIGN AND SETTING: We identified phase 3 or 4 interventional trials: on adult participants (aged >18 years), registered in clinicaltrials.gov between January 1, 2021 and December 31, 2022, and which provided "chronic pain" as a keyword condition. We excluded diagnostic studies and phase 1 or 2 trials. In each trial, one reviewer extracted all outcomes registered and identified those captured using PROMs. For each PROM used in more than 1% of identified trials, two reviewers assessed whether it covered the six important clinical domains from the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials (IMMPACT): pain, emotional functioning, physical functioning, participant ratings of global improvement and satisfaction with treatment, symptoms and adverse events, and participant disposition (eg, adherence to medication). Second, reviewers searched PubMed for both the initial publication and latest review reporting the psychometric properties of each PROM and assessed their content validity, structural validity, internal consistency, reliability, measurement error, hypotheses testing, criterion validity, and responsiveness using published criteria from the literature. RESULTS: In total, 596 trials assessing 4843 outcomes were included in the study (median sample size 60, interquartile range 40-100). Trials evaluated behavioral (22%), device-based (21%), and drug-based (10%) interventions. Of 495 unique PROMs, 55 were used in more than 1% trials (16 were generic pain measures; 8 were pain measures for specific diseases; and 30 were measures of other symptoms or consequences of pain). About 50% PROMs had more than 50% of psychometric properties rated as sufficient. Scales often focused on a single clinical domain. Only 25% trials measured at least three clinical domains from IMMPACT. CONCLUSION: Half of PROMs used in trials assessing interventions for chronic pain had sufficient psychometric properties for more than 50% of criteria assessed. Few PROMs assessed more than one important clinical domain. Only 25% of trials measured more than 3/6 clinical domains considered important by IMMPACT.

Multidimensional versus unidimensional pain scales for the assessment of analgesic requirement in the emergency department: a systematic review.

Pain is a multidimensional experience, potentially rendering unidimensional pain scales inappropriate for assessment. Prior research highlighted their inadequacy as reliable indicators of analgesic requirement. This systematic review aimed to compare multidimensional with unidimensional pain scales in assessing analgesic requirements in the emergency department (ED). Embase, Medline, CINAHL, and PubMed Central were searched to identify ED studies utilizing both unidimensional and multidimensional pain scales. Primary outcome was desire for analgesia. Secondary outcomes were amount of administered analgesia and patient satisfaction. Two independent reviewers screened, assessed quality, and extracted data of eligible studies. We assessed risk of bias with the ROBINS-I tool and provide a descriptive summary. Out of 845 publications, none met primary outcome criteria. Three studies analyzed secondary outcomes. One study compared the multidimensional Defense and Veterans Pain Rating Scale (DVPRS) to the unidimensional Numerical Rating Scale (NRS) for opioid administration. DVPRS identified more patients with moderate instead of severe pain compared to the NRS. Therefore, the DVPRS might lead to a potential reduction in opioid administration for individuals who do not require it. Two studies assessing patient satisfaction favored the short forms (SF) of the Brief Pain Inventory (BPI) and McGill Pain Questionnaire (MPQ) over the Visual Analogue Scale (VAS) and the NRS. Limited heterogenous literature suggests that in the ED, a multidimensional pain scale (DVPRS), may better discriminate moderate and severe pain compared to a unidimensional pain scale (NRS). This potentially impacts analgesia, particularly when analgesic interventions rely on pain scores. Patients might prefer multidimensional pain scales (BPI-SF, MPQ-SF) over NRS or VAS for assessing their pain experience.

Effects of transcutaneous electrical nerve stimulation on pain, function, and descending inhibition in people with non-specific chronic low-back pain: a study protocol for a randomized crossover trial.

BACKGROUND: Low back pain (LBP) is a significant public health problem, is very prevalent, and is often characterized by the persistence of symptoms. Transcutaneous electrical nerve stimulation (TENS) may benefit people with chronic LBP because it can activate descending inhibitory pathways and inhibit central excitability. However, previous studies that have investigated the effects of TENS on pain in people with LBP have failed to use proper intensities of current, and the timing of the assessment of pain was not performed during the peak of the analgesic response or functional activities. Therefore, the present study aims to assess the effects of TENS on measures of pain, function, and descending inhibition using the maximal tolerable intensity of TENS in participants with LBP. METHODS/DESIGN: This study will be a randomized crossover trial. The participants for this study will be recruited from various places, including the University of Hartford, physical therapy clinics, and local businesses in the Hartford area, as well as online websites geared towards clinical trial recruitment. A total of 34 participants will receive all three treatments: active TENS, placebo TENS, and no treatment control. The treatment order will be randomized using a website-based randomization tool. For active TENS, a modulating frequency of 2-125 Hz will be applied with a variable pulse duration and maximal tolerable intensity for 30 min. The TENS will be left on for post-treatment testing to assess the effects during its maximally effective period for a total of 50 to 60 min. Furthermore, the intensity may be turned down if muscle twitching is present to ensure blinding of the evaluator. For placebo TENS, the unit will deliver current for 45 s, ramping to 0 in the last 15 s. The primary outcome will be pain intensity at rest and with movement, determined using the numerical pain rating scale. The secondary outcomes will be pressure pain threshold, heat pain threshold, temporal summation of pain, conditioned pain modulation, sit-to-stand test, and repeated trunk flexion. The assessments will be performed immediately before and after treatment. Statistical analysis of the data obtained will consider a significance level of p < 0.05. DISCUSSION: This study will provide evidence concerning the effects and mechanisms of TENS treatment in participants with chronic non-specific low back pain. The outcomes, including pain, function, and descending inhibition, will help us gain a greater understanding of how TENS can be used for these participants. TRIAL REGISTRATION: ClinicalTrials.gov NCT05812885. Registered on 24th May 2023.

Fluoroscopy-guided high-intensity focused ultrasound neurotomy of the lumbar zygapophyseal joints: a prospective, open-label study.

OBJECTIVE: The objective of this study is to investigate safety and effectiveness of a fluoroscopy-guided high-intensity focused ultrasound (HIFU) system for thermal ablation of the lumbar medial branch nerves. METHODS: This dual center prospective cohort study enrolled 30 participants with lumbar zygapophyseal joint syndrome. Each participant previously had a positive response to either a single diagnostic analgesic block or radiofrequency ablation (RFA). The primary effectiveness outcome was individual responder rate, defined as a reduction of two points or more on the pain intensity numerical rating scale without an increase in opioid intake, or a reduction in opioid intake without an increase in pain at 6 months after the intervention. The primary safety outcome was procedure-related or device-related adverse events (AEs). Secondary outcome variables included MRI evidence of tissue ablation, Oswestry Disability Index, 12-Item Short Form Health Survey, Brief Pain Inventory, and Patient Global Impression of Change. RESULTS: The individual responder rate was 89.7% at 2 days, 89.7% at 7 days, 72.4% at 14 days, 82.1% at 30 days, 59.3% at 90 days and 82.6% at 180 days. The average Numeric Rating Scale for pain severity decreased from 7.1 at baseline to 3.0 (N=29) after 2 days, 3.0 (N=29) after 7 days, 3.1 (N=29) after 14 days, 3.2 (N=28) after 30 days, 4.3 (N=27) after 90 days, and 3.3 (N=23) after 180 days. All participants tolerated the procedure well with no significant side effects or complications. CONCLUSIONS: Fluoroscopy-guided HIFU neurotomy achieved clinical responses comparable with RFA, and there were no significant device-related or procedure-related AEs. TRIAL REGISTRATION NUMBER: NCT04129034.

Evaluation of the antinociceptive activities of natural propolis extract derived from stingless bee Trigona thoracica in mice.

Background: : Stingless bee propolis is a popular traditional folk medicine and has been employed since ancient times. This study aimed to evaluate the antinociceptive activities of the chemical constituents of aqueous propolis extract (APE) collected by Trigona thoracica in a nociceptive model in mice. Methods: : The identification of chemical constituents of APE was performed using high-performance liquid chromatography (HPLC). Ninety-six male Swiss mice were administered APE (400 mg/kg, 1,000 mg/kg, and 2,000 mg/kg) before developing nociceptive pain models. Then, the antinociceptive properties of each APE dose were evaluated in acetic acid-induced abdominal constriction, hot plate test, and formalin-induced paw licking test. Administration of normal saline, acetylsalicylic acid (ASA, 100 mg/kg, orally), and morphine (5 mg/kg, intraperitoneally) were used for the experiments. Results: : HPLC revealed that the APE from Trigona thoracica contained p-coumaric acid (R2 = 0.999) and caffeic acid (R2 = 0.998). Although all APE dosages showed inhibition of acetic acid-induced abdominal constriction, only 2,000 mg/kg was comparable to the result of ASA (68.7% vs. 73.3%, respectively). In the hot plate test, only 2,000 mg/kg of APE increased the latency time significantly compared to the control. In the formalin test, the durations of paw licking were significantly reduced at early and late phases in all APE groups with a decrease from 45.1% to 53.3%. Conclusions: : APE from Trigona thoracica, containing p-coumaric acid and caffeic acid, exhibited antinociceptive effects, which supports its potential use in targeting the prevention or reversal of central and peripheral sensitization that may produce clinical pain conditions.

Definition and Assessment of Paediatric Breakthrough Pain: A Qualitative Interview Study.

Infants, children and young people with life-limiting or life-threatening conditions often experience acute, transient pain episodes known as breakthrough pain. There is currently no established way to assess breakthrough pain in paediatric palliative care. Anecdotal evidence suggests that it is frequently underdiagnosed and undertreated, resulting in reduced quality of life. The development of a standardised paediatric breakthrough pain assessment, based on healthcare professionals' insights, could improve patient outcomes. This study aimed to explore how healthcare professionals define and assess breakthrough pain in paediatric palliative care and their attitudes towards a validated paediatric breakthrough pain assessment. This was a descriptive qualitative interview study. Semi-structured interviews were conducted with 29 healthcare professionals working in paediatric palliative care across the UK. An inductive thematic analysis was conducted on the data. Five themes were generated: 'the elusive nature of breakthrough pain', 'breakthrough pain assessment', 'positive attitudes towards', 'reservations towards' and 'features to include in' a paediatric breakthrough pain assessment. The definition and assessment of breakthrough pain is inconsistent in paediatric palliative care. There is a clear need for a validated assessment questionnaire to improve assessment, diagnosis and management of breakthrough pain followed by increased healthcare professional education on the concept.

Poor postoperative pain control is associated with poor long-term patient-reported outcomes after elective spine surgery: an observational cohort study.

BACKGROUND CONTEXT: A significant proportion of patients experience poorly controlled surgical pain and fail to achieve satisfactory clinical improvement after spine surgery. However, a direct association between these variables has not been previously demonstrated. PURPOSE: To investigate the association between poor postoperative pain control and patient-reported outcomes after spine surgery. STUDY DESIGN: Ambispective cohort study. PATIENT SAMPLE: Consecutive adult patients (≥ 18-years old) undergoing inpatient elective cervical or thoracolumbar spine surgery. OUTCOME MEASURE: Poor surgical outcome was defined as failure to achieve a minimal clinically important difference (MCID) of 30% improvement on the Oswestry Disability Index or Neck Disability Index at follow-up (3-months, 1-year, and 2-years). METHODS: Poor pain control was defined as a mean numeric rating scale score of >4 during the first 24-hours after surgery. Multivariable mixed-effects regression was used to investigate the relationship between poor pain control and changes in surgical outcomes while adjusting for known confounders. Secondarily, the Calgary Postoperative Pain After Spine Surgery (CAPPS) score was investigated for its ability to predict poor surgical outcome. RESULTS: Of 1305 patients, 47.8%, 37.3%, and 39.8% failed to achieve the MCID at 3-months, 1-year, and 2-years, respectively. The incidence of poor pain control was 56.9%. Multivariable analyses showed poor pain control after spine surgery was independently associated with failure to achieve the MCID (OR 2.35 [95%CI=1.59-3.46], p<0.001) after adjusting for age (p=0.18), female sex (p=0.57), any nicotine products (p=0.041), ASA physical status >2 (p<0.001), ≥3 motion segment surgery (p=0.008), revision surgery (p=0.001), follow-up time (p<0.001), and thoracolumbar surgery compared to cervical surgery (p=0.004). The CAPPS score was also found to be independently predictive of poor surgical outcome. CONCLUSION: Poor pain control in the first 24-hours after elective spine surgery was an independent risk factor for poor surgical outcome. Perioperative treatment strategies to improve postoperative pain control may lead to improved patient-reported surgical outcomes.

Relationships Among Pelvic Congestion Syndrome Pain, Daily Activities, and Quality of Life.

OBJECTIVE: To examine women's experiences of pelvic congestion syndrome (PCS) pain. DESIGN: Descriptive, cross-sectional. SETTING: Online questionnaires in a Facebook PCS support group. PARTICIPANTS: Convenience sample of 143 women who self-identified as being diagnosed with PCS. METHODS: We recruited women through a social media support group and invited them to participate in a self-reported questionnaire. We collected demographic information and used the McGill Pain Questionnaire to elicit responses related to pain quality, pain intensity, quality of life, and satisfaction with health care. We analyzed data using descriptive statistics and correlation coefficients. RESULTS: Respondents characterized their PCS pain as exhausting, stabbing, sharp, shooting, and tender. Respondents indicated that 19 of 24 daily activities increased PCS pain, whereas only 5 reduced PCS pain. Pain intensity was negatively related to the quality of life, health satisfaction, sleep, and sexual relationships. CONCLUSION: Chronic pelvic pain from PCS severely affected quality of life among respondents. These findings suggest a difference in the presentation of PCS from historical pain depictions and further highlight the need to identify pain profiles to increase timely and precise diagnosis. Further research is needed to evaluate interventions to increase the quality of life for women with PCS.

ASSESSMENT OF HUMAN FETUSES UNDERGOING ACUTE PAIN: VALIDATION OF THE FETAL-7 SCALE.

Improvements in fetal ultrasound have allowed for the diagnosis and treatment of fetal diseases in the uterus, often though surgery. However, little attention has been drawn to the assessment of fetal pain. To address this gap, a fetal pain scoring system, known as the Fetal-7 scale, was developed. The present study is a full validation of the Fetal-7 scale. The validation involved two steps: i. four fetuses with indication of surgery were evaluated in three conditions perioperatively: acute pain, rest, and under loud sound stimulation. Facial expressions were assessed by 30 raters using screenshots from 4D high-definition ultrasound films; ii., assessment of sensitivity and specificity of the Fetal-7 scale in 54 healthy fetuses and two fetuses undergoing acute pain after preoperative anesthetic intramuscular injection. There was high internal consistency with Cronbach's alpha (α) of 0.99. Intra-rater reliability of the Fetal-7 scale (test-retest) calculated by intraclass correlation coefficient (ICC) was 0.95, and inter-rater reliability was 0.99. The scale accurately differentiated between healthy fetuses at rest and those experiencing acute pain (sensitivity of 100% and specificity of 94.4%). The Fetal-7 scale is a valid tool for assessing acute pain-related behavior in third trimester fetuses and may be of value in guiding analgesic procedures efficacy in these patients. Further research is warranted to explore the presence of post-operative pain in fetuses and its effects afterbirth. PERSPECTIVE: Recordings with three-dimension ultrasound of human fetuses undergoing pre-operative anesthetic injections revealed complex facial expressions during acute pain, similar to those collected in newborns. This study presented the validation process and cut-off value of the Fetal-7 scale, paving the way for the study of pain before birth in humans.

Muscle Pain Code: a novel tool for screening the risk of time-loss muscle injury in professional male football players.

OBJECTIVE: To investigate the association of a novel post-match muscle pain map, named Muscle Pain Code (MPC), with the risk of subsequent time-loss muscle injury in a cohort of professional football (soccer) players. METHODS: The MPC classifies pain in four codes: code 0, 'no pain;' code 1, 'generalized muscle pain;' code 2, 'diffused site muscle pain;' and code 3, 'specific site muscle pain.' Over four consecutive seasons, MPC was collected on the second post-match day and players were followed for occurrence of time-loss muscle injury over the next five days. Players exposed to at least 45 minutes in two consecutive matches within seven days were included as cases for analysis. RESULTS: Eighty players participated in the study. Of 1,656 cases analyzed, 229 resulted in time-loss muscle injuries. Only 2% of cases with codes 0 and 1 resulted in time-loss muscle injuries. Conversely, 63% and 78% of codes 2 and 3 were followed by time-loss muscle injuries, respectively. Compared with the reference scenario (i.e. code 0 on MPC), the risk of subsequent time-loss muscle injury was significantly higher when players recorded code 2 (odds ratio, 4.29; 95%CI, 3.62 to 4.96) or code 3 (odds ratio, 5.01; 95%CI, 4.05 to 5.98) on MPC, but not when they recorded code 1 (odds ratio = -0.27; 95%CI, 1.05 to 0.56). CONCLUSIONS: Players experiencing well-outlined pain area on the second post-match day were more likely to incur a time-loss muscle injury in the subsequent days compared to those experiencing spreading pain or no pain.

Effectiveness of Radiofrequency Ablation for Treatment of Glossopharyngeal Neuralgia: A Systematic Review of the Current Literature.

BACKGROUND: Glossopharyngeal neuralgia (GPN) is a rare cause of facial pain that has an incidence of less than one per 100,000 people. The excruciating stabbing pain experienced by patients with GPN can be debilitating, leading to difficulties in activities of daily living, such as eating and speaking. As a result, there has been a recent increase in research on the effectiveness of radiofrequency ablation (RFA) for treating GPN. OBJECTIVE: The objective of our study was to evaluate the effectiveness of (RFA for treating GPN while examining its impact on patients' quality of life and assesses for any associated side effects. STUDY DESIGN: The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) model was employed to identify articles from 2 comprehensive medical databases. The patient outcomes and numbers from each article were aggregated and calculated in order to determine the percent efficacy of RFA for treating pain associated with GPN. METHODS: In this systematic review, the PRISMA review model was utilized to search through the PubMed and EMBASE databases. A comprehensive literature review was conducted. Of the initial 1,580 articles identified, 18 articles were included for analysis. Studies included in this systematic review encompassed idiopathic cases and secondary causes, such as an elongated styloid process, oropharyngeal cancers, and postsurgical/traumatic pain. RESULTS: Of the 288 patients treated with RFA, 231 experienced relief or complete resolution of pain, yielding an efficacy rate of 80.2%. Most of the patients experienced immediate pain relief after RFA; however, some patients reported numbness, dysphagia, and changes in taste. Our study examines the potential use of RFA as a minimally invasive and effective treatment for GPN. LIMITATIONS: Limitations of our study include the absence of comparisons between different types, modes, and settings of RFA procedures. The use of only 2 medical databases is another limitation. Finally, our systematic review does not include any randomized controlled trials. CONCLUSION: RFA is efficacious in treating GPN with over 80% of patients experiencing postprocedure pain relief. However, further research in the form of clinical and controlled trials is needed to contribute to a better understanding of RFA's long-term outcomes for patients with GPN.

Preliminary Characterization of Age and Chronic Low Back Pain Effects on Multimodal Pain Sensitivity: A Comparison Study in Older Adults with and Without Chronic Low Back Pain.

Though pain sensitivity impairments contribute to chronic pain in younger adults, it is unclear if pain hypersensitivity manifests with aging and is heightened in the geriatric chronic low back pain population. The cross-sectional study preliminarily addressed this gap by measuring pain sensitivity in older adults with chronic low back pain (n = 25) as well as pain-free sex-matched older (n = 25) and younger adults (n = 25). Pain sensitivity was quantified by 8 distinct measures that were subdivided as static (ie, pressure pain thresholds, heat pain thresholds, fixed mechanical pain, and fixed cold pain) and dynamic pain sensitivity (ie, mechanical temporal summation, thermal ramp and hold, heat pain aftersensations, and conditioned pain modulation). Test-retest reliability values for pain sensitivity ranged from moderate to excellent (intraclass correlation coefficients ≥ .500; p's < .05). The main effect for the group was significant (partial η2 = .413, P < .001), revealing between-group differences in pain sensitivity on 5 out of 8 tests (p's ≤ .043). Predominantly, both older adult groups demonstrated increased pain facilitation and decreased pain inhibition during dynamic pain sensitivity testing compared to pain-free younger adults (p's ≤ .044). Despite qualitative differences, static and dynamic pain sensitivity responses were statistically similar between older adults with and without chronic LBP (p's > .05). Findings suggest pain sensitivity can be reliably measured in older adults and that pain hypersensitivity develops with chronological aging, providing partial support for the theory that pain hypersensitivity may impact geriatric chronic pain populations. Further study is needed to more definitively parse out whether pain hypersensitivity is comparatively heightened in older adults with chronic LBP beyond the influence of chronological aging. PERSPECTIVE: This article establishes that surrogate measures of centrally mediated pain sensitization are heightened with aging. Impaired endogenous pain modulation may influence chronic pain development, maintenance, treatment efficacy, and/or ensuing disability, necessitating research to comprehensively characterize how pain hypersensitivity contributes to geriatric chronic pain conditions.

Concurrent validity of dynamic bedside quantitative sensory testing paradigms in breast cancer survivors with persistent pain.

BACKGROUND: Studies on the concurrent validity of clinically applicable testing protocols for conditioned pain modulation (CPM) and temporal summation of pain (TSP) in breast cancer survivors (BCS) with persistent pain are lacking. OBJECTIVES: This study investigated the concurrent validity of two bedside protocols for CPM and TSP in comparison to a respective reference protocol. The participants' preferences for bedside CPM and TSP protocols were assessed. METHODS: Thirty BCS experiencing persistent pain were included in this study. Each participant underwent a reference test along with two bedside alternatives for assessing both TSP and CPM. For CPM, a cold pressor test (CPT) and blood pressure cuff (BPC) were used as conditioning stimulus. The test stimulus was elicited in parallel by pressure pain threshold after 45 and 90 s of conditioning at the lower limb. The CPM reference test consisted of parallel heat stimuli at the forearms using a two-thermode system. TSP was elicited using a von Frey monofilament (256 mN) and an algometer (98 kPa) at the affected site and opposite lower limb. The TSP reference test consisted of heat stimuli at the affected site and opposite lower limb. Participants' testing preference was examined using a purpose-designed questionnaire. Spearman's rank test examined the correlation between protocols. RESULTS: The two bedside CPM protocols were strongly correlated (r = 0.787-0.939, p < 0.005). A strong correlation was found between the BPC protocol and reference test using the relative effect magnitude (r = 0.541-0.555, p < 0.005). The bedside TSP protocols were moderately correlated with each other only at the lower limb using absolute change scores (r = 0.455, p = 0.012). No significant correlation was found between the bedside and reference TSP protocols. CONCLUSION: The significantly moderate to very strong correlations between the bedside protocols validate their interchangeability. Researchers and clinicians should be able to choose which bedside protocol they utilize; however, participants favored the use of a BPC and algometer for the evaluation of CPM and TSP, respectively.

Dimensional assessment of self-reported musculoskeletal symptoms by workers: A multi-case study.

BACKGROUND: Work-related musculoskeletal disorders (WMSD) encompass a range of conditions affecting muscles, tendons, and nerves. Visual diagrams are widely used to identify symptoms and to generate musculoskeletal discomfort metrics. However, there is no consensus on the number of discomfort dimensions that can originate from self-reported musculoskeletal symptoms by individuals. OBJECTIVE: This study aimed to test the fit of WMSD symptom models from workers in two samples of different sizes. METHODS: A combination of Full-Information Item Factor Analysis (FIFA) and Item Response Theory (IRT) was utilized to analyze and test the models. The study was conducted in two samples of workers (n1 = 6944 and n2 = 420) who had their symptoms identified with the aid of a human body diagram. An analysis was conducted considering each sample's unidimensional and three multidimensional models. RESULTS: The unidimensional model (general musculoskeletal discomfort), bi-dimensional model (discomfort in upper and lower body), and tridimensional model (discomfort in the upper limbs, lower limbs, and trunk) showed good values of factor loading and communalities, along with satisfactory item discrimination ability. Regardless of sample size, parameter estimation for IRT and FIFA proceeded without issues, presenting suitable fit parameters. CONCLUSION: Three models were valid and reliable for more extensive and smaller samples. However, the tridimensional model was best for generating discomfort scores in body regions. Companies and safety professionals can use these findings to devise strategies to mitigate musculoskeletal pains based on perceived symptom locations.

Does a diagnosis of depression influence observer ratings of pain severity? The mediating role of causal attributions of pain and pain genuineness.

Researchers have been increasingly investigating observer and patient characteristics that may influence the assessment of pain in others. While rates of psychiatric conditions are high in chronic pain populations, surprisingly little attention has been given to if (and why) a comorbid psychiatric diagnosis may influence the estimation of pain in others. Using an experimental vignette paradigm, the current study examined whether a diagnostic label of major depressive disorder (MDD) would impact observer pain estimates of a woman with chronic pain, and whether causal attributions of pain and pain genuineness might help explain these effects. Participants (n = 188) were given a vignette describing a female patient with chronic pain (who either had MDD or no mental health concerns), viewed a brief video clip of the patient, and then were asked to provide a variety of ratings about the woman's pain. Results of a serial multiple mediation analysis revealed that participants in the MDD condition made greater psychological attributions for the woman's pain, which was associated with lower perceptions of pain genuineness, which was then associated with lower estimates of pain intensity. These findings suggest that a diagnosis of depression may indirectly influence observer estimates of another person's pain by heightening psychological attributions of pain, and making their pain seem less genuine. Further research is needed to elucidate the complex processes underlying pain estimation, including patient and observer characteristics, biases, and heuristics, in order to improve quality of care for those living with persistent pain.'

Biomarkers for assessing pain and pain relief in the neonatal intensive care unit.

Newborns admitted to the neonatal intensive care unit (NICU) regularly undergo painful procedures and may face various painful conditions such as postoperative pain. Optimal management of pain in these vulnerable preterm and term born neonates is crucial to ensure their comfort and prevent negative consequences of neonatal pain. This entails accurate and timely identification of pain, non-pharmacological pain treatment and if needed administration of analgesic therapy, evaluation of treatment effectiveness, and monitoring of adverse effects. Despite the widely recognized importance of pain management, pain assessment in neonates has thus far proven to be a challenge. As self-report, the gold standard for pain assessment, is not possible in neonates, other methods are needed. Several observational pain scales have been developed, but these often rely on snapshot and largely subjective observations and may fail to capture pain in certain conditions. Incorporation of biomarkers alongside observational pain scores holds promise in enhancing pain assessment and, by extension, optimizing pain treatment and neonatal outcomes. This review explores the possibilities of integrating biomarkers in pain assessment in the NICU.

Validation of the Portuguese Version of the Short-Form Glasgow Composite Measure Pain Scale (CMPS-SF) According to COSMIN and GRADE Guidelines.

We aimed to validate the CMPS-SF according to COSMIN and GRADE guidelines. Four trained evaluators assessed 208 videos (pre-operative-M1, peak of pain-M2, 1 h after the peak of pain and analgesia (rescue)-M3, and 24 h post-extubation-M4) of 52 dogs, divided into negative controls (n = 10), soft tissue surgeries (n = 22), and orthopedic surgeries (n = 20). The videos were randomized and blinded as to when they were filmed, and were evaluated in two stages, 21 days apart. According to confirmatory analysis, the CMPS-SF is a unidimensional scale. Intra-observer reliability was between 0.80 and 0.99 and inter-observer reliability between 0.73 and 0.86. Criterion validity was confirmed by the correlation between the CMPS-SF and other unidimensional scales (≥0.7). The differences between the scores were M2 ≥ M3 > M4 > M1 (responsiveness), and the scale presented construct validity (higher postoperative pain scores in dogs undergoing surgery versus control). Internal consistency was 0.7 (Cronbach's α) and 0.77 (McDonald's ω), and the item-total correlation was between 0.3 and 0.7, except for "A(ii)-Attention to wound". Specificity and sensitivity were 78-87% and 74-83%, respectively. The cut-off point for rescue analgesia was ≥5 or ≥4 excluding item B(iii) mobility, and the GRADE classification was high, confirming the validity of the scale.