Citations

Background/importance Spinal cord stimulation (SCS) is an established therapy for chronic pain conditions when conventional treatments fail. However, global research implementation varies significantly due to patient demographics, healthcare infrastructure, and economic factors, creating disparities in access that directly impact patient care and public health outcomes. Objective To evaluate the global landscape of SCS research by analyzing patient demographics, geographic distribution, funding sources, and pain conditions treated across chronic pain populations aged 18 years and older, with primary focus on associations between geographic regions and patient age demographics. Evidence review We conducted a systematic literature review and meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, searching five major databases through October 2024. Studies from 2000 onward reporting SCS in adults with chronic pain lasting 3 months or longer were included. We included randomized trials, comparative studies, and case series with at least 10 patients, excluding commentaries, reviews, and insurance databases. Findings Analysis of 187 studies revealed heterogeneity in age distributions across geographic regions, with Asian studies showing higher mean ages compared to North America, while European showed lower mean ages. Research concentration was predominantly in high-income regions, with 57% of studies receiving industry funding and significant associations between funding source and geographic origin. Post-surgical pain syndrome-thoracolumbar emerged as the most prevalent condition globally, representing 44.9% of cases. Conclusions Significant associations exist between geographic regions and patient demographics in SCS research, with notable disparities in research concentration highlighting the need for broader investigation in underrepresented areas to optimize global application of this chronic pain management therapy. PROSPERO registration number CRD42025635147.

Background Peripheral nerve stimulation (PNS) is an emerging neuromodulation therapy for chronic pain, yet its use in clinical practice varies significantly. Although temporary PNS is widely incorporated, either as a screening trial or a treatment itself, the evidence supporting the use of temporary PNS prior to permanent implantation is limited. We aimed to compare pain relief, opioid consumption, and adverse events between an approach implementing temporary PNS before permanent implantation (temporary-to-permanent (TTP)) vs proceeding directly to permanent PNS implantation (direct-to-permanent (DTP)). Methods A multicenter retrospective study was undertaken at seven major academic institutions from January 1, 2014, to January 1, 2024. Adult patients who underwent permanent PNS implantation for the treatment of chronic pain conditions were included and were divided into TTP or DTP cohorts based on their clinical approach. The dual primary outcomes were pain relief and opioid consumption (in oral morphine equivalents) at 6 months compared with baseline before any PNS therapy. Multivariable Tobit regression analysis was performed to identify predictors of pain relief at 6 months using a stepwise approach. Results A total of 130 patients were analyzed (54 in TTP approach, 76 in DTP approach). Patient-reported percentage pain relief was 56.7%±27.9% at 6 months compared with baseline (before PNS implantation) in the TTP cohort, and 45.1%±33.6% in the DTP cohort. The estimated mean percentage pain relief at 6 months was similar in the TTP and DTP cohorts (between-group difference 15.24%; 95% CI −0.32 to 30.80, p=0.052), with consistent findings after sensitivity analysis with multiple imputation. Opioid consumption declined similarly in the TTP (−3.1±9.9 mg) and DTP (−2.1±8.1 mg) cohorts at 6 months with no statistical difference between cohorts (mean between-group difference: −1.00, 95% CI −4.57 to 2.57, p=0.580), and with consistent findings after sensitivity analysis. Device explantation rates and adverse event profiles were comparable between cohorts. Conclusion Although temporary PNS is widely performed prior to permanent PNS implantation, there was no evidence that the TTP approach is associated with superior analgesic outcomes compared with the DTP approach. Further, patients in both approaches achieved clinically meaningful pain relief at 6 months compared with baseline status prior to PNS therapy.

Introduction The field of neuromodulation has experienced substantial growth, accompanied by an increase in clinical practice guidelines aimed at supporting evidence-based practice. However, adherence to reporting standards remains critical in the development of a comprehensive and transparent clinical practice guideline. This study evaluated the reporting quality of guidelines on neurostimulation for chronic pain by assessing compliance with the Reporting Items for Practice Guidelines in Healthcare (RIGHT) checklist and the Appraisal of Guidelines for Research and Evaluation (AGREE) checklist and explored predictors of reporting quality. Methods A search strategy was conducted from database inception to April 17, 2024 to identify guideline articles on neurostimulation treatment (spinal cord stimulation, dorsal root ganglion stimulation, peripheral nerve stimulation) for chronic pain. Primary outcomes included the percentage of completed RIGHT and AGREE checklist items. Secondary outcomes included the identification of under-reported checklist items, predictors of reporting quality, and agreement between the two checklists. Results A total of 24 guideline articles were included, with a mean percentage of completed items being 55.12%±12.68% for the RIGHT checklist and 52.16%±10.51% for the AGREE checklist. Items that were most frequently under-reported (<25% completion) included themes of population-specific considerations, cost/resource implications, guideline limitations, recommendation development process, magnitude of benefit versus magnitude of harm, and statement of competing interests and how they were managed. Secondary analysis revealed no significant associations between RIGHT/AGREE reporting quality and journal impact factor, year of publication, number of authors, or guideline themes. There was good inter-checklist agreement between the RIGHT and AGREE checklists (intraclass correlation coefficient 0.76, 95% CI 0.44 to 0.90), suggesting overlapping but distinct evaluation criteria. Conclusions Current guidelines of neurostimulation for chronic pain exhibit significant variability in reporting items, with notable deficiencies in the description of key methodological areas. While adherence to established checklists such as RIGHT and AGREE remains poor and inconsistent, these tools provide a critical framework for enhancing comprehensiveness, transparency, and methodological rigor in future guideline development.

Background The Midclavicle Block achieves balanced methylene blue spread across both anterosuperior and posteroinferior periosteal surfaces in cadavers with intact clavicles. Objective To evaluate the anatomical distribution pattern of the Midclavicle Block in cadaveric specimens with midshaft clavicle fractures, with a focus on periosteal coverage and involvement of the fracture site. Methods An anatomical study was conducted on 10 cadavers (20 clavicular regions). A midshaft clavicle fracture model was created, and the Midclavicle Block technique was applied under ultrasound guidance. A methylene blue solution was injected, and dissections were performed to evaluate dye spread primarily in the deep muscular and the clavicular plane, including the fracture site. Probabilistic maps of dye distribution were generated. Results The anatomical dissection in the deep muscular plane revealed consistent staining of the fracture site in all specimens, along with the subclavius muscle and the clavipectoral fascia, while the pectoralis minor muscle remained unaffected in every case. As the dissection progressed toward the infraclavicular brachial plexus plane, no staining of the plexus was observed, with dye spread restricted to the subclavius muscle and adjacent clavipectoral fascia. The mean staining of the anterosuperior and posteroinferior periosteal surfaces was 55.5% (95% CI: 50.6% to 60.4%) and 53.8% (95% CI: 49.5% to 58.1%), respectively. The highest dye concentration was observed in the middle third of the clavicle, corresponding to the fracture zone. Conclusion The Midclavicle Block resulted in effective periosteal coverage and targeted fracture site staining. Clinical studies are needed to confirm its in vivo efficacy, given the limitations inherent to cadaveric specimens.

Background: Periarticular local infiltration analgesia has become an important mainstay of multimodal analgesia after elective total hip arthroplasty (THA). However, the role of novel motor-sparing fascial plane blocks—with or without periarticular local infiltration analgesia—has not been fully elucidated for patients undergoing THA. The authors conducted a network meta-analysis evaluating the relative analgesic effectiveness of motor-sparing fascial plane blocks (quadratus lumborum, erector spinae, and pericapsular nerve group blocks) and periarticular local infiltration analgesia for adult patients undergoing THA. Methods: Randomized trials examining single-injection quadratus lumborum, erector spinae, or pericapsular nerve group blocks, or periarticular local infiltration analgesia, for THA were sought. The primary outcome was area under the curve (AUC) rest pain scores during the period from 0 to 24 h. Secondary outcomes included rest pain scores at 0, 6, 12, and 24 h; postoperative function at 6, 12, and 24 h; analgesic consumption at 0 to 24 h; incidence of opioid-related side effects; and incidence of block-related complications. Network meta-analysis was performed using a frequentist approach. Results: A total of 44 trials (3,579 patients) evaluating the quadratus lumborum block, erector spinae block, pericapsular nerve group block, or periarticular local infiltration analgesia for THA were considered. Network meta-analysis was used to derive the probability of each intervention being the most effective as compared to the others (P score). For AUC 0 to 24 h rest pain, periarticular local infiltration analgesia was the most effective intervention, as demonstrated by a P score of 89%. For postoperative analgesic consumption, the quadratus lumborum block was the most effective intervention, with a P score of 88%. This was followed by the pericapsular nerve group block (74%), the erector spinae block (38%), and periarticular local infiltration analgesia (42%). Conclusions: Periarticular local infiltration analgesia alone provides the most consistent improvements in postoperative rest pain, analgesic consumption, and functional recovery after THA. The addition of a quadratus lumborum block or pericapsular nerve group block to periarticular local infiltration may further improve analgesic outcomes.