Pain Research & Management最新文献

Background: Oral mucositis (OM) is a debilitating complication of cancer therapy, particularly in head and neck cancer patients, with significant adverse effects on quality of life (QoL). Although numerous interventions have been investigated, their impact on QoL remains inconsistently reported and poorly synthesized.

Methods: An umbrella review was conducted following PRISMA 2020 and Joanna Briggs Institute (JBI) guidelines. Five databases (PubMed, Embase, Scopus, Web of Science, and Cochrane Library) were searched from inception to March 2024. Reviews were eligible if they evaluated any therapeutic intervention for OM and reported QoL-related outcomes using validated tools. Methodological quality was appraised using AMSTAR 2, and findings were narratively synthesized and thematically categorized. The protocol was registered in PROSPERO (CRD420251044088).

Results: Eight systematic reviews (257 primary studies) met the inclusion criteria. Photobiomodulation, honey, black mulberry, and botanical agents such as SAMITAL showed consistent improvement in QoL domains, including pain relief, oral function, and emotional well-being. Gabapentin demonstrated potential in reducing opioid use and early mucositis-related pain, though findings were mixed across trials. QoL was most commonly assessed using the EORTC QLQ-C30, FACT-HN, and UW-QOL. Overall, heterogeneity in intervention protocols and QoL instruments limited comparability.

Conclusions: This review highlights the most promising interventions for improving QoL in patients with OM. Standardizing QoL measurement and prioritizing patient-reported outcomes in future trials is essential to inform evidence-based supportive oncology care.

Background: Intraoperative EEG provides a noninvasive window into cortical dynamics under anesthesia, but conventional spectral analysis cannot capture nonstationary modulation patterns linked to nociceptive processing. This study applied Holo-Hilbert spectral analysis (HHSA) to characterize cross-frequency modulation patterns in relation to the Surgical Pleth Index (SPI) during general anesthesia.

Methods: Frontal EEG from 134 female patients undergoing gynecologic surgery was analyzed. Ten-minute segments were first examined to define canonical modulation structures, followed by one-minute epochs synchronized with SPI values to assess dynamic changes. HHSA decomposed each epoch into amplitude modulation patterns across carrier frequencies (1/64-64 Hz). Group comparisons between pain and no-pain epochs were performed using t-tests with Bonferroni correction. A linear mixed-effects model evaluated the effects of SPI, minimum alveolar concentration (MAC), heart rate (HR), and mean arterial pressure (NIBP-m) on alpha-band modulation (8-16-Hz carrier modulated by 3-8-Hz amplitude).

Results: HHSA revealed two dominant cross-frequency interactions within the alpha-carrier band (8-16 Hz): one modulated by 3-6-Hz (high-delta to theta) and another by 1-2-Hz (low-delta) oscillations, indicating layered modulation under anesthesia. During nociceptive states (SPI > 60), modulation power increased in the alpha and high-delta bands, while theta and low-delta modulation weakened. Alpha-band modulation power rose with SPI and declined with MAC.

Conclusions: HHSA revealed distinct cross-frequency modulation patterns reflecting the cortical balance between nociception and analgesia. Alpha-band modulation serves as a physiologically grounded EEG marker for individualized nociception monitoring under general anesthesia.

Introduction: In the emergency department (ED), commonly used analgesics for pain management are nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol, and opioids. The aim of this clinical trial was to evaluate the effectiveness of intravenous (IV) or oral (PO) paracetamol, combined with intramuscular (IM) diclofenac, in patients with acute limb injuries.

Methods: This study utilized a double-blind, randomized controlled design to evaluate three different treatment groups. The trial included healthy adult males aged 18-65 years, who arrived at the ED with acute limb injuries, and an initial pain score of at least 5 on the Numerical Rating Scale (NRS). Participants were randomly assigned in equal numbers to one of three groups: one group received IM diclofenac (75 mg/3 mL), along with oral paracetamol (1000 mg); the second group was given IM diclofenac plus IV paracetamol (1000 mg in 100 mL); and the third group received IM diclofenac (75 mg/3 mL), accompanied by a placebo. The main goal of the study was to compare the average pain reduction among the three groups at 30 min after treatment (t30).

Results: A total of 162 participants were recruited between October 2022 and February 2023. Pain levels were assessed at baseline (t0) and continued to be monitored up to 90 min after medication was administered (t90). The average reduction in pain scores for each group was as follows: diclofenac plus oral paracetamol resulted in a mean decrease of 2.5 ± 0.03, diclofenac plus IV paracetamol had a mean reduction of 2.6 ± 0.03, and diclofenac with placebo showed a mean decrease of 2.2 ± 0.04. These results indicate there was no statistically significant difference in pain relief among the three groups. Additionally, none of the groups required rescue pain medication, and no adverse events were reported in any group.

Conclusion: The results demonstrate that the three treatment groups achieved similar levels of pain relief within the observed timeframe, offering no significant advantage in terms of speed or extent of pain reduction. Nonetheless, additional studies are warranted to explore the potential synergistic effects of combining paracetamol with NSAIDs via various administration routes, as well as to assess possible adverse events, and the necessity for supplemental analgesia. Trial Registration: ClinicalTrials.gov identifier: NCT04199572.

Background: Repetitive transcranial magnetic stimulation (rTMS) of the left primary motor cortex (M1) shows promise for treating neuropathic pain (NP) after spinal cord injury (SCI), but its efficacy remains limited. This study investigated whether combining rTMS on M1 with premotor cortex (PMC) could improve pain relief in SCI patients with NP.

Materials and methods: Thirty-nine subjects with NP post-SCI were randomly assigned to three groups: M1 + PMC (10-Hz rTMS on left M1 and PMC), M1 (10-Hz rTMS on left M1), and sham. They underwent daily rTMS sessions for 4 weeks with 2 days off each week. Pain was assessed using the numerical rating scale (NRS) and the Short-Form McGill Pain Questionnaire-2 (SF-MPQ2). Functional near-infrared spectroscopy (fNIRS) measured activations in bilateral M1, PMC, and primary somatosensory cortex (S1) during a handgrip task.

Results: Pain intensity gradually declined in the M1 + PMC, M1, and sham groups over time. Both the M1 and M1 + PMC groups experienced greater reductions in NRS scores compared to the sham group (p < 0.05), with the M1 + PMC group showing the most significant reduction (p < 0.05). The M1 + PMC group showed pain relief from Weeks 1 to 6, along with notable inhibition of left M1 and the left PMC activation. The decrease in the oxyhemoglobin (HbO) concentration in the left PMC is significantly positively correlated with the improvement of the NRS score (r = 0.607, p = 0.028) and SF-MPQ2 (r = 0.595, p = 0.032), respectively.

Conclusions: High-frequency rTMS targeting both left M1 and the left PMC is more effective for NP after SCI than targeting left M1 alone, indicating a synergistic benefit. Trial Registration: Chinese Clinical Trials Registry: ChiCTR2000029024.

Background: Insulin resistance (IR) has been linked to chronic severe pain (CSP) in previous studies. The triglyceride-glucose (TyG) index serves as an indicator of IR. However, whether TyG control level affects the further CSP incidence has not been well established. In this study, we aimed to identify the association between TyG control level and the risk of CSP.

Methods: Participants with a continuous statement of severe pain in two consecutive waves of investigation from the China Health and Retirement Longitudinal Study were defined as CSP. The TyG control level was divided into four classes. The association between the baseline TyG and TyG control level CSP incidence was analyzed through logistic regression and restricted cubic spline analysis.

Results: A total of 113 (3.18%) of 3546 participants were diagnosed as CSP within 9 years. The TyG index has a significant correlation with high CSP incidence (OR = 1.51 (95% CI, 1.16-1.96), p = 0.020). Further research analyzed the trajectory of TyG changes. After adjusting for various confounding factors, comparing to Class 1 with the best control of TyG, the OR for Class 4 with the worst control was 2.30 (95% CI, 1.01-5.25) with p = 0.048. In restricted cubic spline regression, the relationship between the TyG index and cumulative TyG and CSP is linear.

Conclusions: The TyG index should be regarded as a simple indicator of CSP incidence. Continuous monitoring of the TyG index is more suitable for predicting CSP incident risk compared to a one-time TyG measurement, and long-term, well-controlled management of the TyG index may be an efficient approach to reduce the risk of CSP incidence.

Objective: We aimed to evaluate the association between the radiological grade of lumbar foraminal spinal stenosis (LFSS) and the outcomes of dorsal root ganglion (DRG) pulsed radiofrequency (PRF) treatment.

Materials and methods: This is an observational, single-center study. Patients with LFSS who had undergone lumbar DRG-PRF treatment were evaluated according to the radiological grade of stenosis: Grades 1, 2, and 3. Severity of pain, presence of neuropathic pain, and functional status were assessed using a numerical rating scale (NRS), the Douleur Neuropathique en 4 (DN4) Questionnaire, and the Oswestry Disability Index (ODI) at baseline, first, and third months. The groups by grade consisted of 18, 22, and 23 patients, respectively, for Grades 1, 2, and 3.

Results: NRS scores are similar at baseline and first month, but higher in Group 3 than in Groups 1 and 2 at the third month (p = 0.010, p = 0.04). Similarly, DN4 scores are similar at baseline and first month, but higher in Group 3 than in Group 1 (p = 0.017). ODI scores and weekly analgesic intake at baseline, first, and third months are similar. There are significant decreases in the NRS, DN4, ODI, and weekly analgesic consumption in all groups during follow-up (p < 0.05). The ratios of meaningful pain relief were 72.2%, 68.2%, and 69.6% at the first month, and 50.0%, 63.6%, and 43.5% at the third month for Grades 1, 2, and 3 groups, respectively, without significant differences at the first and third months (p > 0.05).

Conclusion: The DRG-PRF treatment is effective for pain and functional disability in LFSS in all grades, although pain scores remained higher in Grade 3 stenosis at the third month. Studies with larger sample sizes for each stenosis grade may provide more accurate and detailed information.

Background: Fibromyalgia syndrome (FMS) is a chronic pain condition characterised by widespread pain, fatigue, sleep disturbance and cognitive problems. This systematic review aimed to characterise the perioperative experiences of FMS patients undergoing elective surgery, including pain, local anaesthetic (LA) efficacy, complications, and functional outcomes postoperatively.

Methods: This systematic review was reported in accordance with the PRISMA guidelines. The protocol was registered on PROSPERO (CRD: 42022309297). MEDLINE, Embase and CENTRAL were searched from 1990 to 28 June 2024. Two reviewers independently undertook screening, data extraction and quality assessment. A narrative synthesis was conducted.

Results: Nineteen relevant studies published between 1999 and 2024 were identified, mostly focussing on orthopaedic surgeries. Evidence suggests FMS patients may experience more acute postoperative pain at the surgical site and increased widespread spontaneous pain compared to non-FMS individuals. Opioid requirements may also be greater and is linked to the extent of symptomatology. Little data existed on the benefit of LA techniques. Large cohort studies found no overall increase in complications, but within FMS patients undergoing orthopaedic surgery, there were increased 30- and 90-day complications including anaemia, readmissions and pneumonia. Data indicate poorer early postoperative functional recovery in FMS patients. Interestingly, some studies reveal that treating perpetuating visceral pain sources may lead to improvements in spontaneous FMS pain and sensory thresholds beyond 3 months.

Conclusions: The review highlights a paucity of evidence characterising the immediate perioperative course in FMS patients, indicating an important area for future research to optimise patient experiences and outcomes; however, individualised patient discussions are key.

Background: Complex regional pain syndrome (CRPS) is a disabling condition requiring long-term treatment. This study evaluated long-term outcomes in CRPS patients compared to posttraumatic neuralgia (PN) and nociceptive limb pain (NLP) 1-5 years after diagnosis and treatment initiation in a tertiary clinic.

Methods: Patients with CRPS lasting more than 1 year (n = 116), PN (n = 68), or NLP (n = 75) participated in a standardized telephone interview assessing pain intensity, functional impairment, neglect-like symptoms, and disability in daily life and work.

Results: PN patients had higher pain intensity compared to CRPS (NRS 5.7 ± 2.1 vs. 4.5 ± 2.6; main effect: p = 0.005; post hoc test: p = 0.003). Functional outcomes varied significantly between groups (p < 0.001). CRPS patients showed the highest rate of severe impairment (71%), especially in those with ≥ 3 clinical signs, while outcome was better in NLP (p ≤ 0.027), especially in part-time workers. The global impression of disability varied between groups (p = 0.044): PN patients reported a high level of severe disability (70%), while CRPS had the most subjects with "none/slight" disability (23%). Pain and function were tightly linked to perceived disability in all groups. Neither the neglect-like total score (CRPS: 2.4 (2.2-2.6); neuralgia: 2.5 (2.3-2.7); NLP: 2.2 (1.9-2.5); p = 0.055) nor the working ability differed between groups (p = 0.397); however, only in CRPS, neglect-like symptoms were associated with higher pain intensity and global disability, as well as lower functional outcome. CRPS patients treated with corticosteroids (n = 55) had more positive clinical signs at baseline and poorer outcomes than patients without corticosteroids (n = 61).

Conclusions: Long-term impairment, work-related, and global disability in CRPS were similar to those of neuralgia and NLP patients treated in a tertiary pain clinic. Despite shorter disease duration, CRPS patients more often report severe disability, while pain is comparable to other chronic limb pain courses. More pronounced positive signs in CRPS at baseline are associated with poor outcomes. These findings emphasize the heterogeneous course of CRPS and the importance of individualized multidimensional approaches.

Background: Persistent pain is a leading cause of disability worldwide. Long waiting times can adversely affect outcomes and impede effective management; thus, waiting list-targeted interventions may be beneficial.

Objective: To explore the perceptions of people with persistent pain receiving pain science education (PSE) online, en masse, whilst on an NHS waiting list.

Methods: A mixed-methods observational study of people with persistent pain on NHS waiting lists was undertaken. PSE-informed webinars were delivered by Flippin' Pain, a U.K.-based public health campaign. A questionnaire was circulated postwebinar exploring participants' experience of the webinars collectively and future behavioural intentions. Quantitative data were analysed using descriptive statistics. Reflexive thematic analysis was used to analyse qualitative data.

Results: Participants' (n = 114) pain originated primarily from musculoskeletal sources. Postwebinar, participants felt more hopeful about their future (64%), intended to increase activity levels (71%), intended to reduce their opioid use (51%) and felt that they may be more confident to talk to others about their pain (42%). Overall the webinars were well received; they were considered interesting, and participants reported that they provided feelings of hope and empowerment. 80% of participants would recommend the webinars to others, although a small minority of participants were strongly negative about the webinars and found them unhelpful.

Conclusion: Participants on NHS waiting lists with persistent pain predominantly found PSE webinars helpful. It shifted their understanding of pain, and they intended to undertake self-management activities in line with evidence-based care. Appropriately powered RCTs are warranted to robustly investigate the effectiveness of en masse PSE for patients awaiting care.

Peripheral neuropathic pain (PNP), a chronic condition resulting from nerve damage and characterized by altered sensory signaling and central sensitization, poses significant therapeutic challenges. Botulinum toxin (BTX), known for neuromuscular blockades, also exhibits analgesic properties, prompting its investigation for PNP management. However, existing evidence regarding its efficacy and safety is fragmented. This systematic review aimed to synthesize current data on BTX injections for PNP. Guided by PRISMA and the neuromatrix theory, major databases (PubMed, Web of Science, Cochrane, Embase, Scopus, EBSCOhost) were searched up to March 2025. Included studies evaluated BTX (primarily type A) in adults with PNP using validated pain outcomes and reported safety, covering designs from randomized controlled trials (RCTs) to observational research. Independent reviewers performed data extraction and quality assessment using risk of bias tools. This review has been registered on Prospero with the following number: CRD420251022222. The patient groups studied (1343 participants: 547 males and 632 females) showed substantial variability in age, diagnosis, and treatment setting. Results indicated BTX use across diverse PNP etiologies (e.g., trigeminal neuralgia, painful diabetic neuropathy (DN), postherpetic neuralgia, and phantom limb pain) and across multiple countries. RCTs often reported statistically significant reductions in pain intensity and improvements in related outcomes compared with placebo, although effect sizes were heterogeneous and sample sizes were generally modest. Nonrandomized studies suggested similar trends but frequently presented moderate to serious risk of bias. Adverse events were usually mild and transient, most often localized injection-site reactions or temporary facial asymmetry in cranial applications, while serious complications were rare but could not be excluded with confidence because of incomplete safety reporting. Overall, BTX may offer clinically meaningful benefit for selected PNP subtypes, particularly trigeminal neuralgia and painful DN, yet the certainty of evidence remains low to moderate due to study limitations and methodological diversity. Routine use in PNP therefore requires cautious, individualized consideration rather than broad generalization.