Frontiers in pain research (Lausanne, Switzerland)最新文献

Introduction: Neuropathic pain is characterized by mechanical allodynia and thermal (heat and cold) hypersensitivity, yet the underlying neural mechanisms remain poorly understood.

Methods: Using chemogenetic excitation and inhibition, we examined the role of inhibitory interneurons in the basolateral amygdala (BLA) in modulating pain perception following nerve injury.

Results: Chemogenetic excitation of parvalbumin-positive (PV⁺) interneurons significantly alleviated mechanical allodynia but had minimal effects on thermal hypersensitivity. However, inhibition of PV⁺ interneurons did not produce significant changes in pain sensitivity, suggesting that reductions in perisomatic inhibition do not contribute to chronic pain states. In contrast, bidirectional modulation of somatostatin-positive (SST⁺) interneurons influenced pain perception in a modality-specific manner. Both excitation and inhibition of SST⁺ interneurons alleviated mechanical allodynia, indicating a potential compensatory role in nociceptive processing. Additionally, SST⁺ neuron excitation reduced cold hypersensitivity without affecting heat hypersensitivity, whereas inhibition improved heat hypersensitivity but not cold responses.

Discussion: Our findings suggest that, in addition to PV⁺ neurons, SST⁺ interneurons in the BLA play complex roles in modulating neuropathic pain following nerve injury and may serve as a potential target for future neuromodulation interventions in chronic pain management.

Objective: This study aimed to compare the therapeutic effect of PRP and methylene blue injection in patients with discogenic low back pain.

Methods: A total of 40 patients with discogenic low back pain were randomly divided into two groups, with 20 patients in group A receiving platelet-rich plasma injections and 20 patients in group B receiving methylene blue injections. Visual analog scale (VAS) scores, Japanese Orthopaedic Association (JOA) scores, Pfirrmann grades, and MRI apparent diffusion coefficients (ADCs) were recorded in both groups before the injections and 6 months after the injections.

Results: Compared with group B, the postoperative VAS score of group A was significantly decreased, while the JOA score and ADC score were significantly increased (P < 0.05). There was no significant difference in Pfirrmann grade between the two groups after surgery (P > 0.05). In group A, the Pfirrmann grade after surgery was lower than before surgery (P < 0.05), and the ADC score was higher than before surgery (P < 0.05). There was no significant difference in Pfirrmann grade for the patients in group B before and after surgery (P > 0.05), and their ADC score was lower than that before surgery (P < 0.05).

Conclusion: Compared with a methylene blue injection, platelet-rich plasma can significantly reduce pain, improve the function of the lumbar spine, increase the diffusion ability of water molecules in the intervertebral disc, and improve the degree of intervertebral discogenic degeneration in patients with discogenic low back pain.

The use of non-opioid multimodal analgesics (NMA) may enhance pain relief and decrease opioid dependence in managing acute incisional pain, although this remains debated. A clinical trial found NMA ineffective compared to placebo, prompting us to investigate its impact on pain-like behaviors in animal models. In our study, 12 rats underwent plantar incision surgery and were divided into two groups: NMA and vehicle. NMA comprised acetaminophen, celecoxib, gabapentin, and dextromethorphan, with dosages based on human equivalents. We measured paw withdrawal latency (PWL), paw withdrawal threshold (PWT), and spontaneous foot lifting (SFL) behaviors. Before injection, there were no significant differences between the groups in PWL, PWT, or SFL. After treatment, PWL increased in NMA-injected rats (9.8 ± 2.2 s) compared to vehicle (5.9 ± 2.7 s; p = 0.02). SFL frequency decreased in NMA-injected rats (8.0 ± 5.0 count/20-min) vs. vehicle (30.7 ± 18.0 count/20-min; p = 0.013). However, PWT and SFL duration showed no significant changes. This research represents the first exploration of NMA's effects on incisional pain, suggesting it may effectively manage acute postsurgical pain with inflammatory and neuropathic components. Further clinical validation is needed, but our results indicate NMA could be a viable opioid alternative.

Introduction: Snijders Blok-Campeau Syndrome (SNIBCPS) is a neurodevelopmental disorder characterized by intellectual disability, developmental delays, speech impairment, hypotonia, and distinctive facial features. Little is known about pain perception in children with cognitive impairments, such as patients with SNIBCPS. Although it has been noted that some individuals with SNIBCPS have decreased pain sensation and response to painful stimuli, these reports are anecdotal. Therefore, the objective was to better understand this syndrome and the affected individual's perception and response to pain through proxy-reported observational assessments.

Methods: Fifteen caregivers of individuals with a diagnosis of SNIBCPS participated in this mixed-methods anonymous survey study between July and September 2024. The survey questionnaires included the Pediatric Pain Profile, a Pain Sensory Questionnaire, the Non-Communicative Children's Pain Checklist-Revised, and the Individualized Numerical Rating Scale.

Results: Almost a quarter of our respondents reported insensitivity in the affected individual to hard impacts or pressure. Our findings highlight early and past painful experiences in individuals with SNIBCPS who have a range of behaviors to express their pain.

Discussion: Our findings bring awareness about the proper examination of individuals with SNIBCPS. Despite the small sample size, our findings suggest that pain and injuries may go unreported in individuals with SNIBCPS, and individualized parental observational scales may be beneficial for their healthcare providers and their caregivers.

Objectives: The review aimed to evaluate the efficacy of pulsed radiofrequency (PRF) in treating chronic pain by analyzing recent literature.

Study design: This is a narrative review of relevant articles on the effectiveness of PRF for chronic pain.

Methods: Search for papers published between November 2014 and November 2024 in the PubMed database that use PRF to treat chronic pain. We used "Pulsed radiofrequency, PRF, Pulsed RF for Pain, chronic pain, neuropathic pain, cancer pain, and osteoarthritis pain" as search terms. Inclusion criteria are as follows: (1) Patients are clearly diagnosed with chronic pain according to the standards of the International Association for the Study of Pain; (2) Pulsed radiofrequency is used to treat chronic pain; (3) Follow-up assessments are conducted to evaluate the degree of pain relief after PRF treatment; (4) Review articles and articles not related to the treatment of chronic pain are excluded.

Results: Preliminary searches yielded 368 relevant articles. After reviewing the titles and abstracts and evaluating the full texts, we ultimately included 80 articles. These articles cover research on pulsed radiofrequency treatment for various chronic pain conditions, including neuropathic pain, osteoarthritis pain, and cancer pain. The study types are diverse, including randomized controlled trials, cohort studies, and case reports. The publication dates of the articles range from 2014 to 2024, ensuring the timeliness and comprehensiveness of the research findings, which reflect the latest advancements and outcomes in the field of pulsed radiofrequency treatment for chronic pain.

Limitations: This review did not include studies indexed in databases other than PubMed.

Conclusion: This article reviews the research progress of pulsed radiofrequency technology in the field of chronic pain treatment. By searching and analyzing relevant literature from recent years, it summarizes the research findings on the mechanisms of PRF in treating chronic pain, its clinical applications, efficacy evaluation, and safety, and discusses future research directions. This is helpful for clinical physicians to develop more scientific treatment plans when managing chronic pain patients.

Individuals who have visual impairments (IVI) face unique challenges in coping with and adjusting to chronic pain. However, this population remains underrepresented in chronic pain research and often encounters barriers in accessing effective, tailored healthcare. The primary objective of this study is to generate baseline data on the prevalence, types, and impact of chronic pain in this population. The secondary objectives are to identify specific challenges in pain management and provide evidence to identify specific challenges in pain management and to provide evidence that can inform the development of targeted interventions aimed at promoting equitable healthcare and improving quality of life. An international cross-sectional observational study will be conducted using an online survey administered via LimeSurvey. The survey, developed specifically for this project, will be accessible in multiple languages to enhance participation and representativeness. It is designed to capture the unique aspects of chronic pain, ocular and non-ocular forms, in IVI, including barriers to care and management challenges. This protocol aims to establish a comprehensive understanding of chronic pain in IVI. The findings will help bridge current research gaps, guide tailored interventions, and inform policy initiatives, ultimately reducing healthcare disparities and enhancing quality of life for this underserved group.

Background: Fibromyalgia syndrome (FMS) is linked to central sensitization and neuroplastic alterations that contribute to chronic pain, fatigue, cognitive, sleep, and affective disturbances. Conventional treatments offer limited benefit. Non-invasive transcranial electrical stimulation (tES), particularly transcranial direct current stimulation (tDCS), may modulate brain function and relieve symptoms, but findings remain inconsistent.

Objective: To systematically review and meta-analyze the effects of tES on clinical, neurophysiological, neuropsychological, and neurochemical outcomes in FMS.

Methods: Seven databases were searched for studies published between April 2013 and April 2023. Eligible designs included randomized controlled trials, cross-over, one-arm, and case studies involving adult FMS patients. Data extraction followed Cochrane Collaboration guidelines and used RevMan 6.6.0.

Results: Anodal tDCS produced short- to mid-term reductions in pain and mood symptoms, especially when applied over M1 or DLPFC. Longer interventions and repeated sessions enhanced effects, though protocol heterogeneity limited comparability. Both subjective (VAS, NRS) and objective (QST) measures confirmed pain reduction. Cognitive improvements were inconsistent, and quality of life effects were limited. Neurophysiological and neurochemical changes suggested possible mechanisms, though findings varied. Study quality was mixed, with small sample sizes and methodological inconsistencies. Meta-analysis revealed statistically significant but small effects on pain (Hedges' g < 0.2), with limited evidence on clinical relevance.

Conclusions: Anodal tDCS may offer short-term relief of pain and mood symptoms in FMS, potentially through modulation of cortical excitability and neuroplasticity. However, due to variability in findings and methodological limitations, its clinical relevance remains unclear. Future trials should use standardized protocols, assess long-term effects, and include clinically meaningful outcome measures.

Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD42023412332, PROSPERO CRD42023412332.

Chronic pain is one of the leading causes of disability worldwide. It can result in a significant reduction in quality of life and has been associated with decreased neurocognitive performance in attention, memory, and processing speed. Spinal cord stimulation (SCS) is a surgical treatment option for drug-refractory chronic pain. Although SCS can improve pain perception and related physical well-being, the mechanisms by which SCS improves pain perception and affects cognition remain largely unknown. Here, we review the cognitive impairments and neuroanatomical changes that can arise from chronic pain and how SCS treatment impacts these. This review identifies four key regions that may modulate attention, executive and emotional functioning, and memory with SCS: the amygdala, anterior cingulate cortex, thalamus, and somatosensory cortex. These observations suggest a role for SCS to influence and modulate the cognitive-emotional aspects of pain perception. Our review provides new insights to identify potential cortical areas that can serve as biomarkers or neuromodulation targets for SCS treatment. Recognizing the changes in activity within these supraspinal regions during SCS treatment may help individualize pain treatment and induce favorable cognitive shifts.