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Michael A Fishman,1 Ajay B Antony,2 Corey W Hunter,3 Jason E Pope,4 Peter S Staats,5 Rahul Agarwal,6 Allison T Connolly,6 Nirav Dalal,6 Timothy R Deer7 1Center for Interventional Pain and Spine, Exton, PA, USA; 2The Orthopaedic Institute, Gainesville, FL, USA; 3Ainsworth Institute of Pain Management, New York, NY, USA; 4Evolve Restorative Center, Santa Rosa, CA, USA; 5Premier Pain Centers, Shrewsbury, NJ, USA; 6Abbott, Sylmar, CA, USA; 7The Spine and Nerve Center of the Virginias, Charleston, WV, USACorrespondence: Michael A FishmanCenter for Interventional Pain and Spine, 160 North Pointe Blvd Suite 208, Lancaster, PA, 17603, USATel +1 917-543-6588Email mafishman@gmail.comBackground and Aims: Chronic pain affects more adults in the United States than any other condition. Opioid medications are widely used in the treatment of chronic pain, but there remains considerable risk and cost associated with their use. This study aims to characterize the effects of opioid prescribing for chronic pain and similar pain conditions on lost productivity in the United States.Methods: This was a retrospective, longitudinal, observational study of chronic pain patients in 2011– 2014. We identified patients with a diagnosis of musculoskeletal pain receiving index prescription for opioids in administrative claims and studied disability absence in a linked health and productivity management database. Patients were grouped as de novo and continued use opioid users before index, and by opioid dose in the year after index. Days of disability were compared before and after index with bootstrapping. Effect of opioid dose group on disability was evaluated with negative binomial regression. Lost productivity cost was compared before and after index.Results: The cohort contained 16,273 de novo and 6604 continued use patients. On average, de novo patients used 24.8 days of disability after index, an increase of 18.3 more days compared to before (p < 0.001). Continued use patients used 30.7 days after index, 9 more days than before (p < 0.001). There was a dose–response relationship between dose group and days of disability in de novo patients (p < 0.001). The weighted-average cost per person of lost productivity was $4344 higher in the year after index compared to the year before.Conclusion: Opioid prescriptions for pain patients were associated with significant disability use and lost productivity costs. With the evolution of opioid-prescribing practices, CDC recommendations, and the HHS Pain Management Best Practices, there is opportunity to use alternative pain therapies without the risks of opioid-induced side effects to improve work productivity.Keywords: opioids, pain, disability, productivity

Timothy R Deer,1 Sam Eldabe,2 Steven M Falowski,3 Marc A Huntoon,4 Peter S Staats,5 Isaac R Cassar,6 Nathan D Crosby,6 Joseph W Boggs6 1The Spine and Nerve Center of the Virginias, Charleston, WV, USA; 2Department of Pain Medicine, The James Cook University Hospital, Middlesbrough, UK; 3Department of Neurosurgery, Neurosurgical Associates of Lancaster, Lancaster, PA, USA; 4Anesthesiology, Virginia Commonwealth University Medical Center, Richmond, VA, USA; 5Premier Pain Centers, Shrewsbury, NJ, USA; 6SPR Therapeutics, Cleveland, OH, USACorrespondence: Timothy R DeerThe Spine and Nerve Center of the Virginias, 400 Court Street, Suite 100, Charleston, WV, 25301, USATel +1 304/347-6141Fax +1 304/347-6855Email doctdeer@aol.comAbstract: Peripheral nerve stimulation (PNS) is an effective tool for the treatment of chronic pain, although its efficacy and utilization have previously been significantly limited by technology. In recent years, purpose-built percutaneous PNS devices have been developed to overcome the limitations of conventional permanently implanted neurostimulation devices. Recent clinical evidence suggests clinically significant and sustained reductions in pain can persist well beyond the PNS treatment period, outcomes that have not previously been observed with conventional permanently implanted neurostimulation devices. This narrative review summarizes mechanistic processes that contribute to chronic pain, and the potential mechanisms by which selective large diameter afferent fiber activation may reverse these changes to induce a prolonged reduction in pain. The interplay of these mechanisms, supported by data in chronic pain states that have been effectively treated with percutaneous PNS, will also be discussed in support of a new theory of pain management in neuromodulation: Peripherally Induced Reconditioning of the Central Nervous System (CNS).Keywords: chronic pain, neuromodulation, peripheral nerve stimulation, cortical plasticity, peripherally induced reconditioning, mechanism of action

Pierce D Nunley,1 Timothy R Deer,2 Ramsin M Benyamin,3 Peter S Staats,4 Jon E Block5 1Spine Institute of Louisiana, Shreveport, LA 71101, USA; 2Center for Pain Relief, Charleston, WV 25301, USA; 3Millennium Pain Center, Bloomington, IL 61704, USA; 4National Spine and Pain Centers, Rockville, MD 20852, USA; 5Jon Block, San Francisco, CA 94115, USA Background: Lumbar spinal stenosis (LSS) causes significant pain and functional impairment, and medical management has increasingly included the prescription of opioid-based analgesics. Interspinous process decompression (IPD) provides a minimally-invasive treatment option for LSS.Methods: This study estimated the type, dosage, and duration of opioid medications through 5 years of follow-up after IPD with the Superion Indirect Decompression System (Vertiflex Inc., Carlsbad, CA USA). Data were obtained from the Superion-treatment arm of a randomized controlled noninferiority trial. The prevalence of subjects using opiates was determined at baseline through 60 months. Primary analysis included all 190 patients randomized to receive the Superion device. In a subgroup of 98 subjects, we determined opioid-medication prevalence among subjects with a history of opioid use.Results: At baseline, almost 50% (94 of 190) of subjects were using opioid medication. Thereafter, there was a sharp decrease in opioid-medication prevalence from 25.2% (41 of 163) at 12 months to 13.3% (20 of 150) at 24 months to 7.5% (8 of 107) at 60 months. Between baseline and 5 years, there was an 85% decrease in the proportion of subjects using opioids. A similar pattern was also observed among subjects with a history of opiates prior to entering the trial.Conclusion: Stand-alone IPD is associated with a marked decrease in the need for opioid medications to manage symptoms related to LSS. In light of the current opiate epidemic, such alternatives as IPD may provide effective pain relief in patients with LSS without the need for opioid therapy. Keywords: interspinous spacer, Superion, lumbar spinal stenosis, opioids, neurogenic claudication, indirect decompression

Chronic uncontrolled pain may be the greatest health care crisis facing the United States. It is the major symptom for which patients seek medical care and is associated with substantial economic and psychosocial costs. For many patients, particularly the elderly and those suffering from cancer, chronic pain is often undertreated. Because pain has an emotional component and is frequently accompanied by depression and/or anxiety, patients benefit from a comprehensive assessment and multidisciplinary approach to treatment. It is likely that coxibs (cyclooxygenase or COX-2-selective inhibitors) will assume an increasingly prominent role in the treatment of chronic pain associated with arthritis, cancer, and other diseases either as monotherapy or in combination with other drugs. In addition, the role of COX-2 inhibition in the prevention and treatment of colon cancer, Alzheimer's disease (AD), and other chronic health problems is an area currently undergoing intense investigation. [ABSTRACT FROM AUTHOR]

Background: There is paucity of data from randomized controlled trials supporting the use of peripheral nerve stimulation, a well-established therapy for the treatment of chronic pain. This study was undertaken, in part, to provide randomized controlled trial data in support of patient access to appropriate peripheral nerve stimulation therapy. The COMFORT study is the first large, postmarket, multicenter randomized controlled trials investigating the use of a Food and Drug Administration-cleared micro-implantable pulse generator (IPG) for treating chronic pain via peripheral nerve stimulation therapy., Methods: Consented, eligible subjects were randomized to either the active arm, which received peripheral nerve stimulation and conventional medical management, or the control arm, which received conventional medical management alone and were allowed to cross over to the active arm, after 3 months. Pain and patient-reported outcomes were captured. Therapy responders were subjects who achieved at least a 50% reduction in pain scores compared with baseline. We are reporting the 12-month results of this 36-month study., Results: At 12 months, the responder rate was 87% with a 69% average reduction in pain compared with baseline (7.5±1.2 to 2.3±1.7; p<0.001). Statistical significance was achieved for all patient-reported outcomes. There was an excellent safety profile with no serious adverse device effects or reports of pocket pain. A majority of subjects used unique programming options and found this device easy to use and comfortable to wear., Conclusions: These 12-month results are consistent with previously reported 6-month outcomes from this study, showing durability of peripheral nerve stimulation treatment with the micro-IPG system; subjects realized sustained large reduction in pain and improvement in patient-reported outcomes following treatment with this micro-IPG system., Trial Registration Number: NCT05287373., Competing Interests: Competing interests: GH was a consultant at Nalu Medical, Agitated Solutions, and a co-founder of Nesos. PSS is a consultant for Nalu Medical, Saluda, SPR therapeutics, and Medtronic. He is chief medical officer at electroCore. SK is an employee at Nalu Medical. JM is a consultant at Nalu Medical and owns stock in Nalu Medical. JH is a speaker and consultant for Nalu Medical. MJD consults for Medtronic and Nalu; receives research support from Abbott, Avanos, Averitas, Mainstay, Nalu, Nature Cell, Saol, SPR Therapeutics, Vivex; and owns stock options in HyperVention, SPR Therapeutics, SynerFuse, and Virdio., (© American Society of Regional Anesthesia & Pain Medicine 2024. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ.)

Introduction: The International Neuromodulation Society convened a multispecialty group of physicians based on expertise with international representation to establish evidence-based guidance on using intrathecal drug delivery in chronic pain treatment. This Polyanalgesic Consensus Conference (PACC)® project's scope is to provide evidence-based guidance for clinical pharmacology and best practices for intrathecal drug delivery for cancer pain., Materials and Methods: Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches using Medline, EMBASE, Cochrane CENTRAL, BioMed Central, Web of Science, Google Scholar, PubMed, Current Contents Connect, Meeting Abstracts, and Scopus from 2017 (when the PACC last published guidelines) to the present. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations were based on the strength of evidence, and when evidence was scant, recommendations were based on expert consensus., Results: The PACC evaluated the published literature and established evidence- and consensus-based expert opinion recommendations to guide best practices in treating cancer pain. Additional guidance will occur as new evidence is developed in future iterations of this process., Conclusions: The PACC recommends best practices regarding the use of intrathecal drug delivery in cancer pain, with an emphasis on managing the unique disease and patient characteristics encountered in oncology. These evidence- and consensus-based expert opinion recommendations should be used as a guide to assist decision-making when clinically appropriate., Competing Interests: Conflict of Interest Shane E. Brogan acts as a paid consultant for Medtronic. Eric Buchser reports grants from the Swiss National Foundation and the Commission for Technology and Innovation; and grants, personal fees and nonfinancial support from Medtronic, during the conduct of the study. Timothy R. Deer reports no conflicts that pertain to intrathecal therapy; reports conflicts within the neuromodulation field that include consulting for Abbott, Saluda, Ethos, Nalu, PainTeq, and Cornorloc; he also holds a patent pending with Abbott; is on the advisory board of Abbott and Nalu; has stock options Saluda, Spinethera, and Nalu; and has institutional research grants from Abbott, Saluda, Vertiflex and Mainstay. Denis Dupoiron reports personal fees from Medtronic and Esteve during the conduct of the study. Amitabh Gulati reports personal fees from Medtronic, Flowonix, AIS HealthCare, SPR Therapeutics, Nalu Medical, Bausch Health, and Spark Medical, outside the submitted work. Jennifer Hah reports grants from NIH NIDA, outside the submitted work. Gladstone C. McDowell II reports personal fees and other from Medtronic Corporation; personal fees, nonfinancial support, and other from Flowonix Corporation and TerSera Therapeutics, outside the submitted work. Christophe Perruchoud reports grants and personal fees from Medtronic and Boston Scientific, during the conduct of the study; and personal fees from Medtronic and Boston Scientific, outside the submitted work. Fabian Piedimonte reports personal fees from Medtronic and Abbott, which stopped in June 2020. Julie G. Pilitsis reports grants and other from Boston Scientific, Nevro, Abbott, Medtronic, and TerSera; other from Saluda; grants from NIH 2R01CA166379-06, other from Aim Medical Robotics and Karuna Labs; and grants from NIH U44NS115111, outside the submitted work. Jason E. Pope reports other from Ethos Labs, Flowonix, Saluda, PainTeq, Aurora Spine, Thermaquil, Celeri Health, Spine Thera, AGR, NIS, Abbott, Medtronic, Biotronik, Mainstay, Muse, AIS, SPR Therapeutics, TerSera, Vertiflex, Boston Scientific, Vertos, SPARK, and WISE, outside the submitted work. Michael F. Saulino reports research grants from Medtronic and Flowonix; fellowship support from Medtronic, Piramal, and Saol. Peter S. Staats reports grants from Saluda, Nalu, AIS Therapeutics, Thermaquil, Biotronik, electroCore and Vertos, outside the scope of this work; royalties from the Averitas-Qutenza Patch, outside the scope of this work; payment or honoraria from Medtronic and SPR Therapeutics, outside the scope of this work; patents for vagus nerve and topical capsaicin products; participation in a Data Safety Monitoring or Advisory Board for Nalu and Saluda; a leadership role in the World Institute of Pain, American Society of Pain and Neuroscience, American Society of Interventional Pain Physicians, and the Florida Academy of Pain Management; and stock options in Saluda, Nalu and electroCore. Mark S. Wallace reports grants from NIH and is a consultant to TerSera. Tony L. Yaksh reports grants from NIH NINDS, other from CODA, IONIS, and Medtronic, during the conduct of the study; and grants from NIH-NINDS, IONIS, and Medtronic, outside the submitted work. The remaining authors reported no conflict of interest., (Copyright © 2024 International Neuromodulation Society. Published by Elsevier Inc. All rights reserved.)

Objectives: Spinal cord stimulation (SCS) has been challenged by the lack of neurophysiologic data to guide therapy optimization. Current SCS programming by trial-and-error results in suboptimal and variable therapeutic effects. A novel system with a physiologic closed-loop feedback mechanism using evoked-compound action potentials enables the optimization of physiologic neural dose by consistently and accurately activating spinal cord fibers. We aimed to identify neurophysiologic dose metrics and their ranges that resulted in clinically meaningful treatment responses., Materials and Methods: Subjects from 3 clinical studies (n = 180) with baseline back and leg pain ≥60 mm visual analog scale and physical function in the severe to crippled category were included. Maximal analgesic effect (MAE) was operationally defined as the greatest percent reduction in pain intensity or as the greatest cumulative responder score (minimal clinically important differences [MCIDs]) obtained within the first 3 months of SCS implant. The physiologic metrics that produced the MAE were analyzed., Results: We showed that a neural dose regimen with a high neural dose accuracy of 2.8μV and dose ratio of 1.4 resulted in a profound clinical benefit to chronic pain patients (MAE of 79 ± 1% for pain reduction and 12.5 ± 0.4 MCIDs). No differences were observed for MAE or neurophysiological dose metrics between the trial phase and post-implant MAE visit., Conclusion: For the first time, an evidence-based neural dose regimen is available for a neurostimulation intervention as a starting point to enable optimization of clinical benefit, monitoring of adherence, and management of the therapy., Competing Interests: Conflict of Interest Robert M. Levy is an uncompensated consultant for Biotronik, Abbott, Nalu, Saluda, and Mainstay Medical and has stock options from Nalu and Saluda Medical. Nagy A. Mekhail reports receiving grants from Neuros, Mesoblast, and Vivex Biologics, as well as consulting as a medical monitor for Saluda Medical, Nevro, Vivex Biologics, Mainstay, Presidio Medical, and Vertos outside the submitted work. Leonardo Kapural reports receiving grants from Nevro, Neuros, Avanos, Medtronic, Neuralace, and Xalud Therapeutics and financial support from Nevro, Avanos, and Saluda Medical outside the submitted work. Christopher A. Gilmore reports personal fees and other assistance from SPR, and personal fees from Nevro, Nalu, Biotronik, Boston Scientific, and Saluda Medical outside the submitted work. Erika A. Petersen has received research support from Mainstay, Medtronic, Neuros Medical, Nevro Corp, ReNeuron, SPR, and Saluda Medical outside the submitted work, as well as personal fees from Abbott Neuromodulation, Biotronik, Medtronic Neuromodulation, Nalu, Neuros Medical, Nevro, Presidio Medical, Saluda Medical, and Vertos outside the submitted work. She holds stock options from SynerFuse and neuro42. Jonathan H. Goree is a consultant for Saluda Medical, Abbott, and Stratus Medical outside the submitted work. He has received research support paid to the institution by SPR Therapeutics and Mainstay Medical. Jason E. Pope reports research and consulting fees from Saluda Medical during the conduct of the study; stock options from Saluda Medical; consultancy for Abbott, Medtronic, Saluda Medical, Flowonix, SpineThera, Vertos, Vertiflex, SPR Therapeutics, Tersera, Aurora, Spark, Ethos, Biotronik, Mainstay, WISE, Boston Scientific, and Thermaquil outside the submitted work; has received grant and research support from Abbott, Flowonix, Aurora, Painteq, Ethos, Muse, Boston Scientific, SPR Therapeutics, Mainstay, Vertos, AIS, and Thermaquil outside the submitted work; and is a minority shareholder of Vertos, Stimgenics, SPR Therapeutics, Painteq, Aurora, Spark, Celeri Health, Neural Integrative Solutions, Pacific Research Institute, Thermaquil, Abbott and Anesthetic Gas Reclamation. Shrif J. Costandi reports receiving grants from Saluda Medical, Vertos, Mainstay, and Vivex outside the submitted work. Jan Willem Kallewaard is an advisory board member for Boston Scientific, Medtronic, Abbott, and Saluda Medical. Simon Thomson has received consultancy fees from Boston Scientific, Mainstay Medical, and Saluda Medica outside the submitted work. He has received department research funding from the National Institute for Health Research, Boston Scientific, Saluda Medical, and Mainstay Medical. Christopher Gilligan reports consulting fees and stock options received from Mainstay, personal fees from Mainstay, Saluda Medical, Persica, and Iliad outside the submitted work, research funded by Sollis, expert witness testimony fees, and serves as Editor-in-Chief of Pain Practice. Corey W. Hunter has received consultancy fees from Saluda Medical and Genecentrix outside the submitted work. Kasra Amirdelfan reports consultancy for Medtronic, Nevro, Boston Scientific, Nalu, Presidio, Biotronik, Mesoblast, and Vivex Laboratories outside the submitted work. Steven M. Falowski reports consulting fees from Abbott, Medtronic, Saluda, VertiFlex, Vertos, Surgentec, CornerLoc, Mainstay, and Relievant outside the submitted work, has received a grant for research funding from Mainstay, Relievant, Medtronic, Abbott, VertiFlex, Saluda, Nalu, CornerLoc, Aurora, Biotronik, and Stimgenics outside the submitted work, and has an equity position in SynerFuse, Aurora Spine, Thermaquil. SPR Therapeutics, Saluda, CornerLoc, PainTEQ, Stimgenics, Anesthetic Gas Reclamation, Neural Integrative Solutions, SpineThera, and Celeri Health. Sean Li reports receiving grants and personal fees from Saluda Medical during the conduct of the study; he reports grants from Avanos, Nalu Medical, SPR Therapeutics, Averitas Pharma, Biotronik, Neuralace, Presidio, SGX Therapeutics, and PainTeq, as well as consultancy for Abbott, Avanos, Presidio, SPR Therapeutics, Averitas Pharma, Biotronik, Nalu Medical, PainTeq, and Vertos Medical outside the submitted work, as well as holding stock options for Nalu Medical and NeuroOne. Shivanand P. Lad reports personal fees from Mainstay Medical and Nevro outside the submitted work; he is a consultant for Abbott Laboratories, Boston Scientific, Higgs Boson Health, Medtronic, Minnetronix, Nevro, and Presidio Medical. Dawood Sayed reports personal fees from Abbott, Boston Scientific, Flowonix, Medtronic, Nevro, Saluda, and Vertiflex outside the submitted work, personal fees and stock options from Mainstay, SPR Therapeutics, PainTEQ, and Vertos, and stock options from Neuralace and Surgentec. Ajay Antony reports consultancy fees from Boston Scientific outside the submitted work. Timothy R. Deer reports consultancy for Axonics, Abbott, Nalu, Vertos, SpineThera, Mainstay, Cornerloc, Ethos, SPR Therapeutics, Medtronic, Boston Scientific, PainTeq, Saluda Medical, Tissue Tech, Spinal Simplicity, and Avanos outside the submitted work. Maged N. Guirguis has received consulting fees from Avanos Medical, Avertis Pharmacy, Boston Scientific, and Saluda Medical outside the submitted work, as well as research support from Boston Scientific, Neuros Medical, Nevro Corp, and Saluda Medical outside the submitted work. Aaron K. Calodney reports personal fees from Medtronic, Nevro, Stryker, PainTeq, Saluda Medical, and Boston Scientific outside the submitted work. Brian Bruel reports consultancy for Saluda Medical, Boston Scientific, Spinal Simplicity, Biotronik, TerSera, Stratus, and Neurovasis outside the submitted work. Patrick Buchanan reports consulting fees from Saluda Medical, Abbott, and PainTEQ outside the submitted work. Nicole Soliday, Rui V. Duarte, and Angela Leitner report being employees of Saluda Medical. Peter S. Staats has received consultancy fees from Medtronic, Saluda Medical, Nalu, and Biotronic outside the submitted work, and has stock options from Saluda Medical and Nalu. The remaining authors report no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: Different types of spinal cord stimulation (SCS) have been evaluated for the management of chronic nonsurgical refractory back pain (NSRBP). A direct comparison between the different types of SCS or between closed-loop SCS with conventional medical management (CMM) for patients with NSRBP has not been previously conducted, and therefore, their relative effectiveness and cost-effectiveness remain unknown. The aim of this study was to perform a systematic review, network meta-analysis (NMA) and economic evaluation of closed-loop SCS compared with fixed-output SCS and CMM for patients with NSRBP., Methods: Databases were searched to September 8, 2023. Randomized controlled trials of SCS for NSRBP were included. The results of the studies were combined using fixed-effect NMA models. A cost-utility analysis was performed from the perspective of the UK National Health Service with results reported as incremental cost per quality-adjusted life-year (QALY)., Results: Closed-loop SCS resulted in statistically and clinically significant reductions in pain intensity (mean difference [MD] 32.72 [95% CrI 15.69-49.78]) and improvements in secondary outcomes (Oswestry Disability Index [ODI] and health-related quality of life [HRQoL]) compared with fixed-output SCS at 6-month follow-up. Compared with CMM, both closed-loop and fixed-output SCS resulted in statistically and clinically significant reductions in pain intensity (closed-loop SCS vs. CMM MD 101.58 [95% CrI 83.73-119.48]; fixed-output SCS versus CMM MD 68.86 [95% CrI 63.43-74.31]) and improvements in secondary outcomes (ODI and HRQoL). Cost-utility analysis showed that closed-loop SCS dominates fixed-output SCS and CMM, and fixed-output SCS also dominates CMM., Discussion: Current evidence showed that closed-loop and fixed-output SCS provide more benefits and cost-savings compared with CMM for patients with NSRBP., Competing Interests: This work was supported by Saluda Medical. S.E. reports consultancy fees from Medtronic, and Mainstay Medical outside the submitted work. He has received department research funding from the National Institute of Health Research, Saluda Medical and Medtronic. S.N. reports consultancy fees from Saluda Medical. A.B. MTech Access was commissioned by Saluda Medical to participate in this project. N.A.M. reports receiving grants from Neuros, Mesoblast, and Vivex Biologics, as well as consulting as a medical monitor for Saluda Medical, Nevro, Vivex Biologics, Mainstay, Sollis Therapeutics, and Vertos outside the submitted work. C.G. reports consulting fees and stock options received from Mainstay, personal fees from Mainstay, Saluda Medical, Persica, and Iliad outside the submitted work, research funded by Sollis, expert witness testimony fees, and serves as Editor-in-Chief of Pain Practice. B.B. reports an educational grant from Saluda Medical and consultancy fees from Salvia Bioelectronics, Medtronic and Abbott outside the submitted work. P.S.S. has received consultancy fees from Medtronic, Saluda Medical, Nalu, and Biotronic outside the submitted work, and has stock options from Saluda Medical and Nalu. M.M. reports no conflicts of interest. N.S., A.L., and R.V.D. are employees of Saluda Medical. R.V.D. has previously received consultancy fees from Mainstay Medical, Medtronic, and Saluda Medical outside the submitted work., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: We report the results from the first large, postmarket, multicentre, randomised controlled trial (RCT) evaluating peripheral nerve stimulation (PNS) for the treatment of chronic peripheral pain with a micro-implantable pulse generator (micro-IPG)., Methods: Subjects meeting eligibility were randomised (2:1) to either the active arm receiving PNS and conventional medical management (CMM) or the control arm receiving CMM alone. Treatments were limited to the following areas: lower back, shoulder, knee and foot/ankle., Results: At 6 months, the active arm achieved an 88% responder rate with a 70% average reduction in pain. At the 3-month primary endpoint, the active arm achieved an 84% responder rate with an average pain reduction of 67% compared with the control arm, which achieved a 3% responder rate with an average pain reduction of 6%. Both responder rate and pain reduction in the active arm were significantly better than in the control arm (p<0.001). A majority of patient-reported outcomes also reached statistical significance. There have been no reports of pocket pain and no serious adverse device effects. 81% of subjects found the external wearable component of the PNS system to be comfortable., Conclusions: This study successfully reached its primary endpoint-the active arm achieved a statistically significant superior responder rate as compared with the control arm at 3 months. These RCT results demonstrated that PNS, with this micro-IPG, is efficacious and safe. This ongoing study will follow subjects for 3 years, the results of which will be reported as they become available., Competing Interests: Competing interests: GH is a consultant at Nalu Medical, Agitated Solutions, and a co-founder of Nesos. PS is a consultant for Nalu Medical, Saluda, SPR therapeutics and Medtronic. He is the Chief Medical Officer at electroCore. SK is an employee at Nalu Medical. JM is a consultant at Nalu Medical and owns stock in Nalu Medical. JH is a speaker and consultant for Nalu Medical. MJD consults for Avanos, Nalu, SPR Therapeutics; receives research support from Abbott, Avanos, Averitas, Mainstay, Nalu, Nature Cell, Saol, SPR Therapeutics and Vivex; and owns stock options in SPR Therapeutics, SynerFuse and Virdio., (© American Society of Regional Anesthesia & Pain Medicine 2024. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ.)

Introduction: The evidence for spinal cord stimulation (SCS) has been criticized for the absence of blinded, parallel randomized controlled trials (RCTs) and limited evaluations of the long-term effects of SCS in RCTs. The aim of this study was to determine whether evoked compound action potential (ECAP)-controlled, closed-loop SCS (CL-SCS) is associated with better outcomes when compared with fixed-output, open-loop SCS (OL-SCS) 36 months following implant., Methods: The EVOKE study was a multicenter, participant-blinded, investigator-blinded, and outcome assessor-blinded, randomized, controlled, parallel-arm clinical trial that compared ECAP-controlled CL-SCS with fixed-output OL-SCS. Participants with chronic, intractable back and leg pain refractory to conservative therapy were enrolled between January 2017 and February 2018, with follow-up through 36 months. The primary outcome was a reduction of at least 50% in overall back and leg pain. Holistic treatment response, a composite outcome including pain intensity, physical and emotional functioning, sleep, and health-related quality of life, and objective neural activation was also assessed., Results: At 36 months, more CL-SCS than OL-SCS participants reported ≥50% reduction (CL-SCS=77.6%, OL-SCS=49.3%; difference: 28.4%, 95% CI 12.8% to 43.9%, p<0.001) and ≥80% reduction (CL-SCS=49.3%, OL-SCS=31.3%; difference: 17.9, 95% CI 1.6% to 34.2%, p=0.032) in overall back and leg pain intensity. Clinically meaningful improvements from baseline were observed at 36 months in both CL-SCS and OL-SCS groups in all other patient-reported outcomes with greater levels of improvement with CL-SCS. A greater proportion of patients with CL-SCS were holistic treatment responders at 36-month follow-up (44.8% vs 28.4%), with a greater cumulative responder score for CL-SCS patients. Greater neural activation and accuracy were observed with CL-SCS. There were no differences between CL-SCS and OL-SCS groups in adverse events. No explants due to loss of efficacy were observed in the CL-SCS group., Conclusion: This long-term evaluation with objective measurement of SCS therapy demonstrated that ECAP-controlled CL-SCS resulted in sustained, durable pain relief and superior holistic treatment response through 36 months. Greater neural activation and increased accuracy of therapy delivery were observed with ECAP-controlled CL-SCS than OL-SCS., Trial Registration Number: NCT02924129., Competing Interests: Competing interests: NM reports personal fees from Saluda Medical for acting as independent medical monitor for the EVOKE study during the conduct of the study; he reports receiving grants from Neuros and Mesoblast, as well as consulting as a medical monitor for Nevro, Vivex, Mainstay, and Vertos outside the submitted work. RL is an uncompensated consultant for Nalu, Saluda Medical, and Mainstay Medical and has stock options from Nalu and Saluda Medical obtained before 2019, not exercisable through the duration of his term as International Neuromodulation Society President and editor-in-chief of the journal Neuromodulation: Technology at the Neural Interface. TD reports personal fees from Saluda Medical during the conduct of the study; consultancy for Axonics, Abbott, Nalu, Vertos, SpineThera, Mainstay, Cornerloc, Ethos, SPR Therapeutics, Medtronic, Boston Scientific, PainTeq, Tissue Tech, Spinal Simplicity, and Avanos outside the submitted work. He is a minor equity holder for Saluda Medical, Nalu, SpineThera, Stimgenics, Vertiflex, Vertos, and Bioness and an advisory board member for Abbott, Vertos, Nalu, SPR Therapeutics, and Tissue Tech. LK reports receiving grants from Nevro, Neuros, Avanos, Medtronic, Neuralace, and Xalud Therapeutics and financial support from Nevro, Avanos, and Saluda Medical outside the submitted work. SL reports receiving grants and personal fees from Saluda Medical during the conduct of the study; he reports grants from Avanos, Boston Scientific, Nalu Medical, SPR Therapeutics, Averitas Pharma, Biotronik, SGX Therapeutics, and PainTeq, as well as consultancy for Abbott, Avanos, Boston Scientific, Nevro, SPR Therapeutics, Averitas Pharma, Biotronik, Nalu Medical, and PainTeq, outside the submitted work, as well as holding stock options for Nalu Medical. KA reports consultancy for Medtronic, Nevro, Boston Scientific, Nalu, Presidio, Biotronik, Mesoblast, Vivex Laboratories outside the submitted work. JP reports research and consulting fees from Saluda Medical during the conduct of the study; consultancy for Abbott, Medtronic, Saluda Medical, Flowonix, SpineThera, Vertos, Vertiflex, SPR Therapeutics, Tersera, Aurora, Spark, Ethos, Biotronik, Mainstay, WISE, Boston Scientific, and Thermaquil outside the submitted work; has received grant and research support from: Abbott, Flowonix, Aurora, Painteq, Ethos, Muse, Boston Scientific, SPR Therapeutics, Mainstay, Vertos, AIS, and Thermaquil outside the submitted work; and is a shareholder of Vertos, SPR Therapeutics, Painteq, Aurora, Spark, Celeri Health, Neural Integrative Solutions, Pacific Research Institute, Thermaquil, and Anesthetic Gas Reclamation. CH reports grants from Saluda Medical during the conduct of the study; consultancy fees from Genecentrix outside the submitted work. SC reports grants from Cleveland Clinic during the conduct of the study; and grants from Vertos, Mainstay, and Vivex outside the submitted work. SMF reports consulting fees from Abbott, Medtronic, Saluda, VertiFlex, Vertos, Surgentec, CornerLoc, Mainstay and Relievant outside the submitted work, has received grant for research funding from Mainstay, Relievant, Medtronic, Abbott, VertiFlex, Saluda, Nalu, CornerLoc, Aurora, Biotronik, and Stimgenics outside the submitted work, and has an equity position in SynerFuse, Aurora Spine, Thermaquil. SPR Therapeutics, Saluda, CornerLoc, PainTEQ, Stimgenics, Anesthetic Gas Reclamation, Neural Integrative Solutions, SpineThera, and Celeri Health. CG reports clinical trial funding from Saluda Medical during the conduct of the study; reports personal fees and other from SPR, and personal fees from Nevro, Nalu, Biotronik, and Boston Scientific outside the submitted work. PSS has received consultancy fees from Medtronic, Saluda Medical, Nalu, and Biotronic outside the submitted work, and has stock options from Saluda Medical and Nalu. JS reports personal fees from Nevro during the conduct of the study and personal fees from Saluda Medical and Boston Scientific outside the submitted work. TM reports research fees from Saluda Medical during the conduct of the study and personal fees from Nevro outside the submitted work. JC reports personal fees from Saluda Medical during the conduct of the study; personal fees from Abbott, Boston Scientific, Nevro, Medtronic, Mainstay, SPR Therapeutics, CornerLoc, PillNurse, Biotronik, and Vivex outside the submitted work; and stock from Mainstay, CornerLoc, and PillNurse. EP has received research support from Mainstay, Medtronic, Neuros Medical, Nevro Corp, ReNeuron, SPR, and Saluda Medical outside the submitted work, as well as personal fees from Abbott Neuromodulation, Biotronik, Medtronic Neuromodulation, Nalu, Neuros Medical, Nevro, Presidio Medical, Saluda Medical, and Vertos outside the submitted work. She holds stock options from SynerFuse and neuro42. JMH reports consulting fees from Abbott, Boston Scientific, Nevro, and Saluda Medical outside the submitted work. RR reports grants from SPR, Nalu and Nevro outside the submitted work,l fees from Presidio, and grants and personal fees from Boston Scientific and Saluda Medical outside the submitted work. JWK is an advisory board member for Boston Scientific, Medtronic, Abbott, and Saluda Medical. GB reports consulting fees from Medtronic, Boston Scientific, and Saluda Medical outside the submitted work, and has a consulting agreement and is on the advisory board for Nevro Corp, Nalu Medical Inc, Abbott, and Boston Scientific. RST reports consulting fees from Medtronic, Nevro and Saluda Medical outside the submitted work. LP reports personal fees from Saluda Medical; is a member of the data monitoring board of Saluda Medical during the conduct of the study; and reports personal consulting fees from Medtronic and Nalu outside the submitted work. Members of the EVOKE study group report being employees of Saluda Medical. No other disclosures were reported., (© American Society of Regional Anesthesia & Pain Medicine 2024. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ.)

Background: This prospective longitudinal study compares outcomes for Medicare beneficiaries receiving outpatient percutaneous image-guided lumbar decompression (PILD) using the mild ® procedure to patients undergoing outpatient laminectomy. All patients were diagnosed with lumbar spinal stenosis (LSS) with neurogenic claudication (NC)., Methods: All medical claims for 100 % of Medicare beneficiaries were reviewed, with study subjects identified using Centers for Medicare and Medicaid Research Identifiable Files. Baseline data were extracted individually to allow for longitudinal analysis through two-year follow-up. The index procedure was defined as the first mild or outpatient laminectomy during the enrollment period. The rate of subsequent surgical procedures and incidence of harms were used as study outcomes., Results: Cohorts included 2197 mild and 7416 laminectomy patients. mild patients were significantly older (76.7 years versus 73.4 years, respectively; p < 0.0001), and 57.4 % of mild were female, compared to 43.3 % of laminectomy (p < 0.0001). mild patients presented with significantly more baseline comorbidities compared to laminectomy patients (mean of 5.7 versus 4.8, respectively; p < 0.0001). Subsequent surgical procedure rate of 9.0 % for mild was significantly higher than 5.5 % for laminectomy (p < 0.0001). mild experienced harms at a significantly lower rate than laminectomy (1.9 % versus 5.8 %, respectively; p < 0.0001). The composite rate of subsequent surgical procedures and harms was similar between groups at 10.8 % for mild and 11.0 % for laminectomy., Conclusions: mild can be considered a viable option for treatment of LSS with NC as evidenced by real-world data in this study. At two-years, mild patients experienced fewer harms and underwent more subsequent surgical procedures than laminectomy patients. The higher rate of subsequent surgical procedures for mild may be attributable to its position earlier in the LSS treatment algorithm. The overall rate of harms and subsequent surgical procedures was similar between groups, suggesting that mild should be considered as a treatment option, particularly for older patients with multiple comorbidities., Competing Interests: PS reports consulting or research grants from Medtronic, Saluda Medical, Biotronik, AIS Healthcare, Nalu, SPR Therapeutics and funded research from Vertos Medical. MD is a consultant for Abbott, Biotronik, Camber Spine, Globus, Nevro and LifeSpine. DR and NS report no conflicts. LP is a consultant for Medtronic and Saluda Medical, and holds stock options for Nalu and Saluda. JH reports no conflicts., (© 2024 The Authors.)

Introduction: Chronic pain patients may experience impairments in multiple health-related domains. The design and interpretation of clinical trials of chronic pain interventions, however, remains primarily focused on treatment effects on pain intensity. This study investigates a novel, multidimensional holistic treatment response to evoked compound action potential-controlled closed-loop versus open-loop spinal cord stimulation as well as the degree of neural activation that produced that treatment response., Methods: Outcome data for pain intensity, physical function, health-related quality of life, sleep quality and emotional function were derived from individual patient level data from the EVOKE multicenter, participant, investigator, and outcome assessor-blinded, parallel-arm randomized controlled trial with 24 month follow-up. Evaluation of holistic treatment response considered whether the baseline score was worse than normative values and whether minimal clinical important differences were reached in each of the domains that were impaired at baseline. A cumulative responder score was calculated to reflect the total minimal clinical important differences accumulated across all domains. Objective neurophysiological data, including spinal cord activation were measured., Results: Patients were randomized to closed-loop (n=67) or open-loop (n=67). A greater proportion of patients with closed-loop spinal cord stimulation (49.3% vs 26.9%) were holistic responders at 24-month follow-up, with at least one minimal clinical important difference in all impaired domains (absolute risk difference: 22.4%, 95% CI 6.4% to 38.4%, p=0.012). The cumulative responder score was significantly greater for closed-loop patients at all time points and resulted in the achievement of more than three additional minimal clinical important differences at 24-month follow-up (mean difference 3.4, 95% CI 1.3 to 5.5, p=0.002). Neural activation was three times more accurate in closed-loop spinal cord stimulation (p<0.001 at all time points)., Conclusion: The results of this study suggest that closed-loop spinal cord stimulation can provide sustained clinically meaningful improvements in multiple domains and provide holistic improvement in the long-term for patients with chronic refractory pain., Trial Registration Number: NCT02924129., Competing Interests: Competing interests: LK reports receiving grants from Nevro, Neuros, Avanos, Medtronic, Neuralace, and Xalud Therapeutics and financial support from Nevro, Avanos, and Saluda Medical. NM reports receiving grants from Neuros and Mesoblast, as well as consulting as a medical monitor for Saluda Medical, Nevro, Vivex, Mainstay, and Vertos. SC reports receiving grants from Saluda Medical, Vertos, Mainstay, and Vivex. CG reports personal fees and other from SPR, and personal fees from Nevro, Nalu, Biotronik, Boston Scientific, Saluda Medical, and Shiratronics. JP serves as a consultant for Abbott, Medtronic, Saluda Medical, Flowonix, SpineThera, Vertos, Vertiflex, SPR Therapeutics, Tersera, Aurora, Spark, Ethos, Biotronik, Mainstay, WISE, Boston Scientific, and Thermaquil; has received grant and research support from: Abbott, Flowonix, Saluda Medical, Aurora, Painteq, Ethos, Muse, Boston Scientific, SPR Therapeutics, Mainstay, Vertos, AIS, and Thermaquil; and is a shareholder of Vertos, SPR Therapeutics, Painteq, Aurora, Spark, Celeri Health, Neural Integrative Solutions, Pacific Research Institute, Thermaquil, and Anesthetic Gas Reclamation. SL reports receiving grants from Avanos, Boston Scientific, Nalu Medical, SPR Therapeutics, Saluda Medical, Averitas Pharma, Biotronik, SGX Therapeutics, and PainTeq, as well as serving as a consultant for Abbott, Avanos, Boston Scientific, Nevro, SPR Therapeutics, Averitas Pharma, Biotronik, Nalu Medical, PainTeq, and Saluda Medical, as well as holding stock options for Nalu Medical. CH has received consultancy fees from Saluda Medical and Genecentrix. PSS has received consultancy fees from Medtronic, Saluda Medical, Nalu, and Biotronic and has stock options from Saluda Medical and Nalu. RST reports consultancy fees from Medtronic, Nevro and Saluda Medical. SE reports consultancy fees from Medtronic, Mainstay Medical, Boston Scientific, and Abbott. He has received department research funding from the National Institute of Health Research, Medtronic and Nevro. JWK is an advisory board member for Boston Scientific, Medtronic, Abbott, and Saluda Medical. ST has received consultancy fees from Boston Scientific, Mainstay Medical, and Saluda Medical. He has received department research funding from the National Institute for Health Research, Boston Scientific, Saluda Medical, and Mainstay Medical. EP has received research support from Mainstay, Medtronic, Neuros Medical, Nevro Corp, ReNeuron, SPR, and Saluda Medical, as well as personal fees from Abbott Neuromodulation, Biotronik, Medtronic Neuromodulation, Nalu, Neuros Medical, Nevro, Presidio Medical, Saluda Medical, and Vertos. She holds stock options from SynerFuse and neuro42. DS is a consultant for Abbott, Medtronic, Nevro, SPR, Vertos, PainTEQ, and Saluda Medical and has received research funding from and holds minority equity in Vertos. TD is a consultant for Abbott, Vertos, SpineThera, Saluda Medical, Cornerloc, SPR Therapeutics, PainTeq, Spinal Simplicity, and Biotronik. He has minor equity in form of stock options for Vertos, Saluda Medical, Cornerloc, Nalu, PainTeq, and Spinal Simplicity, and minor equity in common stock for SpineThera, and Ethos. He is an advisory board member or participates on a data safety monitoring board for Abbott, Vertos, SPR Therapeutics, and Biotronik. AA reports consultancy fees from Boston Scientific. AL, NS and RD are employees of Saluda Medical. RD has previously received consultancy fees from Mainstay Medical, Medtronic Ltd, and Saluda Medical. RL is an uncompensated consultant for Nalu, Saluda Medical, and Mainstay Medical and has stock options from Nalu and Saluda Medical obtained before 2019, not exercisable through the duration of his term as International Neuromodulation Society President and editor-in-chief of the journal Neuromodulation: Technology at the Neural Interface., (© American Society of Regional Anesthesia & Pain Medicine 2024. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ.)

Introduction: A novel, spinal cord stimulation (SCS) system with a physiologic closed-loop (CL) feedback mechanism controlled by evoked compound action potentials (ECAPs) enables the optimization of physiologic neural dose and the accuracy of the stimulation, not possible with any other commercially available SCS systems. The report of objective spinal cord measurements is essential to increase the transparency and reproducibility of SCS therapy. Here, we report a cohort of the EVOKE double-blind randomized controlled trial treated with CL-SCS for 36 months to evaluate the ECAP dose and accuracy that sustained the durability of clinical improvements., Methods: 41 patients randomized to CL-SCS remained in their treatment allocation and were followed up through 36 months. Objective neurophysiological data, including measures of spinal cord activation, were analyzed. Pain relief was assessed by determining the proportion of patients with ≥50% and ≥80% reduction in overall back and leg pain., Results: The performance of the feedback loop resulted in high-dose accuracy by keeping the elicited ECAP within 4µV of the target ECAP set on the system across all timepoints. Percent time stimulating above the ECAP threshold was >98%, and the ECAP dose was ≥19.3µV. Most patients obtained ≥50% reduction (83%) and ≥80% reduction (59%) in overall back and leg pain with a sustained response observed in the rates between 3-month and 36-month follow-up (p=0.083 and p=0.405, respectively)., Conclusion: The results suggest that a physiological adherence to supra-ECAP threshold therapy that generates pain inhibition provided by ECAP-controlled CL-SCS leads to durable improvements in pain intensity with no evidence of loss of therapeutic effect through 36-month follow-up., Competing Interests: Competing interests: NM reports personal fees from Saluda Medical for acting as independent medical monitor for the EVOKE study during the conduct of the study; he reports receiving research grants from Neuros, Mesoblast, and Vivex Biologics, as well as consulting as a medical monitor of Nevro, Vivex Biologics, Mainstay, Sollis Therapeutics, and Vertos outside the submitted work. RL is an uncompensated consultant of Biotronik, Abbott, Nalu, Saluda, and Mainstay Medical and has stock options from Nalu and Saluda Medical. TD reports personal fees from Saluda Medical during the conduct of the study and consultancy for Axonics, Abbott, Nalu, Vertos, SpineThera, Mainstay, CornerLoc, Ethos, SPR Therapeutics, Medtronic, Boston Scientific, PainTEQ, Tissue Tech, Spinal Simplicity, and Avanos outside the submitted work. He is a minor equity holder of Saluda Medical, Nalu, SpineThera, Stimgenics, Vertiflex, Vertos, and Bioness and an advisory board member of Abbott, Vertos, Nalu, SPR Therapeutics, and Tissue Tech. LK reports receiving grants from Nevro, Neuros, Avanos, Medtronic, Neuralace, and Xalud Therapeutics and financial support from Nevro, Avanos, and Saluda Medical outside the submitted work. SL reports receiving grants and personal fees from Saluda Medical during the conduct of the study; he reports grants from Avanos, Boston Scientific, Nalu Medical, SPR Therapeutics, Averitas Pharma, Biotronik, SGX Therapeutics, and PainTEQ, as well as consultancy for Abbott, Avanos, Boston Scientific, Nevro, SPR Therapeutics, Averitas Pharma, Biotronik, Nalu Medical, and PainTEQ, outside the submitted work, as well as holding stock options for Nalu Medical. KA reports consultancy for Medtronic, Nevro, Boston Scientific, Nalu, Presidio, Biotronik, Mesoblast, and Vivex Laboratories outside the submitted work. CH reports grants from Saluda Medical during the conduct of the study and consultancy fees from Genecentrix outside the submitted work. SC reports research grants from Saluda Medical to the Cleveland Clinic during the conduct of the study and grants from Vertos, Mainstay, and Vivex outside the submitted work. SMF reports consulting fees from Abbott, Medtronic, Saluda, VertiFlex, Vertos, Surgentec, CornerLoc, Mainstay, and Relievant outside the submitted work; has received grant for research funding from Mainstay, Relievant, Medtronic, Abbott, VertiFlex, Saluda, Nalu, CornerLoc, Aurora, Biotronik, and Stimgenics outside the submitted work; and has an equity position in SynerFuse, Aurora Spine, Thermaquil, SPR Therapeutics, Saluda, CornerLoc, PainTEQ, Stimgenics, Anesthetic Gas Reclamation, Neural Integrative Solutions, SpineThera, and Celeri Health. JP reports research and consulting fees from Saluda Medical during the conduct of the study and consultancy for Abbott, Medtronic, Saluda Medical, Flowonix, SpineThera, Vertos, Vertiflex, SPR Therapeutics, Tersera, Aurora, Spark, Ethos, Biotronik, Mainstay, WISE, Boston Scientific, and Thermaquil outside the submitted work; has received grant and research support from Abbott, Flowonix, Aurora, PainTEQ, Ethos, Muse, Boston Scientific, SPR Therapeutics, Mainstay, Vertos, AIS, and Thermaquil outside the submitted work; and is a shareholder of Vertos, SPR Therapeutics, PainTEQ, Aurora, Spark, Celeri Health, Neural Integrative Solutions, Pacific Research Institute, Thermaquil, and Anesthetic Gas Reclamation. CG reports clinical trial funding from Saluda Medical during the conduct of the study and reports personal fees and others from SPR and personal fees from Nevro, Nalu, Biotronik, and Boston Scientific outside the submitted work. PSS has received consultancy fees from Medtronic, Saluda Medical, Nalu, and Biotronic outside the submitted work and has stock options from Saluda Medical and Nalu. JS reports personal fees from Nevro during the conduct of the study and personal fees from Saluda Medical and Boston Scientific outside the submitted work. TM reports research fees from Saluda Medical during the conduct of the study and personal fees from Nevro outside the submitted work. RR reports grants from SPR, Nalu, and Nevro outside the submitted work, personal fees from Presidio, and grants and personal fees from Boston Scientific and Saluda Medical outside the submitted work. RD, NS, AL, EH, ZO, and DM report being employees of Saluda Medical. LP reports personal fees from Saluda Medical, is a member of the data monitoring board of Saluda Medical during the conduct of the study, and reports personal consulting fees from Medtronic and Nalu outside the submitted work. No other disclosures were reported., (© American Society of Regional Anesthesia & Pain Medicine 2024. Re-use permitted under CC BY-NC. No commercial re-use. Published by BMJ.)

Objectives: The effectiveness of Evoke closed-loop spinal cord stimulation (CL-SCS), a novel modality of neurostimulation, has been demonstrated in a randomized controlled trial (RCT). The objective of this cost-utility analysis was to develop a de novo economic model to estimate the cost-effectiveness of Evoke CL-SCS when compared with open-loop SCS (OL-SCS) for the management of chronic back and leg pain., Methods: A decision tree followed by a Markov model was used to estimate the costs and outcomes of Evoke CL-SCS versus OL-SCS over a 15-year time horizon from the UK National Health Service perspective. A "high-responder" health state was included to reflect improved levels of SCS pain reduction recently reported. Results are expressed as incremental cost per quality-adjusted life year (QALY). Deterministic and probabilistic sensitivity analysis (PSA) was conducted to assess uncertainty in the model inputs., Results: Evoke CL-SCS was estimated to be the dominant treatment strategy at ~5 years postimplant (ie, it generates more QALYs while cost saving compared with OL-SCS). Probabilistic sensitivity analysis showed that Evoke CL-SCS has a 92% likelihood of being cost-effective at a willingness to pay threshold of £20,000/QALY. Results were robust across a wide range of scenario and sensitivity analyses., Discussion: The results indicate a strong economic case for the use of Evoke CL-SCS in the management of chronic back and leg pain with or without prior spinal surgery with dominance observed at ~5 years., Competing Interests: This study was funded by Saluda Medical. R.V.D. has received consultancy fees from Mainstay Medical, Medtronic Ltd, and Saluda Medical. The work reported within this manuscript was finalized before R.V.D. joined Saluda Medical as an employee. AB MTech Access was commissioned by Saluda Medical to undertake this project. R.V.D., N.S., and A.L. are employees of Saluda Medical. A.G. has received honoraria for consulting as well as advisory board meetings for Nevro Corp, Boston Scientific Corp, and Abbott. P.S.S. serves as a consultant for Abbott, Nevro and Medtronic. He has received research support from Boston Scientific, Abbott, Vertos, Nevro, Saluda Medical and Grunenthal Halyard. D.S. is a consultant for Abbott, Boston Scientific, Flowonix, Medtronic, Nevro, PainTEQ, SPR Therapeutics, Vertos, and Vertiflex. S.M.F. serves as a consultant for Abbott, Medtronic, Nevro, Saluda, SPR, and Vertiflex. He has received research support from Abbott, Medtronic, Nuvectra, and Saluda Medical. C.W.H. has ownership in Axonics, PainTEQ, Nalu, Spine BioPharma, and Mainstay; consults for Saluda Medical and Genecentrix; is on the speaker’s bureau for Tersera; has research funding from Abbott, Biotronik, DiscGenics, Mesoblast, Saluda, TissueGene, and Vivex; and serves on the advisory boards of Abbott, Mainstay, Nalu, Spine BioPharma, and Vertiflex. R.S.T. has received consultancy fees from Medtronic Ltd, Nevro Corp, and Saluda Medical. The remaining author declares no conflict of interest., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

Objective: This prospective longitudinal study compares outcomes between Medicare beneficiaries receiving percutaneous image-guided lumbar decompression (PILD) using the mild® procedure and a control group of patients receiving interspinous spacers for the treatment of lumbar spinal stenosis (LSS) with neurogenic claudication (NC)., Methods: Patients diagnosed with LSS with NC and treated with either the mild procedure or a spacer were identified in the Medicare claims database. The incidence of harms, the rate of subsequent interventions, and the overall combined rate of harms and subsequent interventions during 2-year follow-up after the index procedure were compared between the two groups and assessed for statistical significance with p = 0.05., Results: The study included 2229 patients in the mild group and 3401 patients who were implanted with interspinous spacers. The rate of harms for those treated with the mild procedure was less than half that of patients implanted with a spacer (5.6% vs. 12.1%, respectively; p < 0.0001) during 2-year follow-up. The rate of subsequent interventions was not significantly different between the two groups (24.9% and 26.1% for the mild and spacer groups, respectively; p = 0.7679). The total rate of harms and subsequent interventions for mild was found to be noninferior to spacers (p < 0.0001)., Conclusions: This comprehensive study of real-world Medicare claims data demonstrated a significantly lower rate of harms for the mild procedure compared to interspinous spacers for patients diagnosed with LSS with NC, and a similar rate of subsequent interventions during 2-year follow-up., (© 2023 World Institute of Pain.)

Introduction: The Evoke® spinal cord stimulation (SCS) device enables the closed-loop feedback of dynamically measured evoked compound action potentials (ECAPs) to adjust stimulation amplitude for every stimulation pulse to maintain the stimulation output level near a targeted ECAP amplitude. No other commercially available SCS device presently uses physiologic feedback from the spinal cord to adjust stimulation. Clinicians should be familiar with the differences in devices and with the latest technologies to provide optimized patient care., Areas Covered: In this device profile, the Evoke system is described and the system capabilities are differentiated from other available SCS devices. A systematic review was conducted based on best practice guidance to identify all available evidence on the safety and efficacy of the Evoke SCS system., Expert Opinion: The Evoke SCS system offers unique capabilities as a means to optimize therapy delivery tailored to each individual patient. Data through 24-months follow-up show statistically significant, clinically meaningful, ample, consistent, and strong evidence of the safety and efficacy of the Evoke system for the treatment of chronic intractable pain.

Objectives: Pain score, functional disability, and health-related quality of life (HRQoL) are core outcome domains for chronic pain clinical trials. Although greater levels of pain reduction have been shown to be linked to larger gains in HRQoL, little is known of the association between HRQoL and disability in the setting of chronic pain. The aims of this study were to 1) investigate the association between functional disability and HRQoL and 2) estimate the utility values associated with levels of functional disability in patients treated with evoked compound action potential (ECAP) spinal cord stimulation (SCS) for chronic pain., Materials and Methods: Data on functional disability assessed using the Oswestry Disability Index (ODI) and HRQoL (EQ-5D-5L) were collected from 204 patients with an Evoke ECAP-SCS device and followed up to 12 months. SF-6D utility scores also were retrieved for 134 of these patients. Multivariable linear regression models adjusted for baseline utility values and patient demographics were used to compare differences in utility values across ODI categories., Results: Significant improvements in functional disability and HRQoL were observed at three- and 12-month follow-up after SCS. Patients reporting "minimum disability," "moderate disability," "severe disability," and "crippled" had mean EQ-5D scores of 0.82, 0.73, 0.59, and 0.45, respectively. The mean change in EQ-5D score was 0.007 per unit change in total ODI score. The R 2 statistic showed a moderate level association (49%-64% of variance in EQ-5D explained by ODI)., Conclusion: ECAP-SCS results in significant improvements in functional disability and HRQoL. This study shows that improvement in function of people with chronic pain before and after ECAP-SCS is associated with improvement in HRQoL., (Copyright © 2022 International Neuromodulation Society. Published by Elsevier Inc. All rights reserved.)

Background: Treatment response to spinal cord stimulation (SCS) is focused on the magnitude of effects on pain intensity. However, chronic pain is a multidimensional condition that may affect individuals in different ways and as such it seems reductionist to evaluate treatment response based solely on a unidimensional measure such as pain intensity., Aim: The aim of this article is to add to a framework started by IMMPACT for assessing the wider health impact of treatment with SCS for people with chronic pain, a "holistic treatment response"., Discussion: Several aspects need consideration in the assessment of a holistic treatment response. SCS device data and how it relates to patient outcomes, is essential to improve the understanding of the different types of SCS, improve patient selection, long-term clinical outcomes, and reproducibility of findings. The outcomes to include in the evaluation of a holistic treatment response need to consider clinical relevance for patients and clinicians. Assessment of the holistic response combines two key concepts of patient assessment: (1) patients level of baseline (pre-treatment) unmet need across a range of health domains; (2) demonstration of patient-relevant improvements in these health domains with treatment. The minimal clinical important difference (MCID) is an established approach to reflect changes after a clinical intervention that are meaningful for the patient and can be used to identify treatment response to each individual domain. A holistic treatment response needs to account for MCIDs in all domains of importance for which the patient presents dysfunctional scores pre-treatment. The number of domains included in a holistic treatment response may vary and should be considered on an individual basis. Physiologic confirmation of therapy delivery and utilisation should be included as part of the evaluation of a holistic treatment response and is essential to advance the field of SCS and increase transparency and reproducibility of the findings., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Poorly managed chronic spinal pain encumbers medical resources and drives healthcare costs, suggesting a target for improvement., Objectives: To determine how specialist-care pathways influence healthcare costs in the first year after a referral for chronic spine pain., Study Design: This was a retrospective cohort analysis of administrative claims from a large commercial health insurance provider, analyzing a 6-month baseline, a variable "pre-referral period," and a one-year period of specialist care., Setting: US patients covered by private commercial insurers., Methods: Adult patients diagnosed with chronic, spine-related pain between July 2016 and February 2018 and under the active care of a specialist were eligible. Patients with neurological deficits or cancer-related pain were excluded. Patients were categorized based on sequence-dependent exposure to a pain specialist, a surgeon, or both specialties. Key measures were pain-related and all-cause medical resource use and costs and opioid prescription fills., Results: Of 306,080 eligible patients (mean age 61.6; 61.5% women), 13% saw a pain specialist, 71% a surgeon, 7% a pain specialist then a surgeon, and 9% a surgeon then a pain specialist. Referral to a pain specialist alone was associated with lower resource use and per-patient adjusted cost savings of $3,311 (pain-related) and $6,447 (all-cause) compared to patients referred to a surgeon alone. The pain specialist pathway was associated with increased indicators of prescription opioid use., Limitations: Cohort design constraints temper the results' generalizability, given the need to simultaneously examine specialty pathway and medical resource incurred over the same time period., Conclusions: We observed meaningful savings in cost and resource use when chronic spine-pain patients were managed by pain specialists. Pain-management referrals should be an element of a thoughtfully designed care pathway.

Background: Chronic pain is a common and growing problem in the United States with variable strategies for its treatment. Surgical interventions are necessary in some cases but not required for all patients with new-onset pain. For some patients, interventional pain management (IPM) techniques can treat chronic pain without the cost or risk associated with surgical intervention., Objective: The objective of this study was to compare healthcare utilization and costs for new-onset chronic pain treated by IPM specialists to those treated by providers with surgical specialties (i.e., orthopedists and neurosurgeons)., Study Design: This was a retrospective observational study of qualifying patients over 36-months (2016-2019)., Setting: This study was conducted using 100% Medicare FFS Parts A, B, and Prescription Drug Event (PDE) Part D data, including enrollment and claims., Methods: Patients with a diagnosis of pain were identified in the claims data. Twelve months of pre-period claims were examined to ensure the incident diagnosis of pain, and 2 additional pain diagnoses were required after initial diagnosis. Patients were assigned either to the IPM cohort or a Surgical cohort based on the specialty of the provider involved in their first pain-related visit after initial diagnosis. Key outcomes, such as the utilization of healthcare services and cost of care, were evaluated for both cohorts over the 24-months following the index diagnosis of pain., Results: 106,658 beneficiaries were included in the study with roughly 36% in the IPM cohort. Patients in the IPM cohort were less healthy and had lower incomes in the baseline period compared to the Surgical cohort. Fewer members of the IPM cohort had an inpatient stay in the 24-months post index pain diagnosis (40% compared to 43% in the surgery cohort) and the IPM cohort had fewer patients with a post-acute care stay (29% compared to 31% in the inpatient stay cohort). The IPM cohort had lower risk-adjusted total costs of care than the Surgical cohort, driven by lower inpatient, outpatient, and post-acute care costs., Limitations: Retrospective claims data may not include some factors important to patients with a pain diagnosis (such as over-the-counter medications, holistic treatments, or pain scores)., Conclusion(s): By shifting patients from higher-cost and more invasive surgical procedures, IPM's multidisciplinary approach to pain treatment can reduce surgical utilization and costs for certain chronic pain patients. This shift away from more expensive surgical treatments fits well with Medicare's move toward value-based care, driven by a focus on patient outcomes including health care utilization and costs.

Background: Epidural injections are among the most commonly performed procedures for managing low back and lower extremity pain. Pinto et al and Chou et al previously performed systematic reviews and meta-analyses, which, along with a recent update from Oliveira et al showing the lack of effectiveness of epidural steroid injections in managing lumbar disc herniation, spinal stenosis, and radiculopathy. In contrast to these papers, multiple other systematic reviews and meta-analyses have supported the effectiveness and use of epidural injections utilizing fluoroscopically guided techniques. A major flaw in the review can be related to attributing active-controlled trials to placebo-controlled trials. The assumption that local anesthetics do not provide sustained benefit, despite extensive evidence that local anesthetics provide long-term relief, similar to a combination of local anesthetic with steroids is flawed., Study Design: The Cochrane Review of randomized controlled trials (RCTs) of epidural injections in managing chronic low back and lower extremity pain with sciatica or lumbar radiculopathy were reanalyzed using systematic methodology and meta-analysis., Objectives: To re-evaluate Cochrane data on RCTs of epidural injections in managing chronic low back and lower extremity pain with sciatica or lumbar radiculopathy utilizing qualitative and quantitative techniques with dual-arm and single-arm analysis., Methods: In this systematic review, we have used the same RCTs from the Cochrane Review of a minimum of 20% change in pain scale or significant pain relief of >= 50%. The outcome measures were pain relief and functional status improvement. Significant improvement was defined as 50% or greater pain relief and functional status improvement. Our review was performed utilizing the Cochrane Review methodologic quality assessment and the Interventional Pain Management Techniques - Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB). Evidence was summarized utilizing the principles of best evidence synthesis and the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) system. Clinical relevance of the pragmatic nature of each study was assessed., Results: In evaluating the RCTs in the Cochrane Review, 10 trials were performed with fluoroscopic guidance. Utilizing conventional dual-arm and single-arm meta-analysis, the evidence is vastly different from the interpretation of the data within the Cochrane Review. The overall combined evidence is Level I, or strong evidence, at one and 3 months, and Level II, or moderate evidence, at 6 and 12 months., Limitations: The limitation of this study is that only data contained in the Cochrane Review were analyzed., Conclusion: A comparative systematic review and meta-analysis of the Cochrane Review of randomized controlled trials (RCTs) of epidural injections in managing chronic low back and lower extremity pain with sciatica or lumbar radiculopathy yielded different results. This review, based on the evidence derived from placebo-controlled trials and active-controlled trials showed Level I, or strong evidence, at one and 3 months and Level II at 6 and 12 months. This review once again emphasizes the importance of the allocation of studies to placebo-control and active-control groups, utilizing standards of practice with inclusion of only the studies performed under fluoroscopic guidance.

Background: In the midst of the COVID-19 pandemic, data has shown that age-adjusted overdose death rates involving synthetic opioids, psychostimulants, cocaine, and heroin have been increasing, including prescription opioid deaths, which were declining, but, recently, reversing the trends. Contrary to widely held perceptions, the problem of misuse, abuse, and diversion of prescription opioids has been the least of all the factors in recent years. Consequently, it is important to properly distinguish between the role of illicit and prescription opioids in the current opioid crisis. Multiple efforts have been based on consensus on administrative policies for certain harm reduction strategies for individuals actively using illicit drugs and reducing opioid prescriptions leading to curbing of medically needed opioids, which have been ineffective. While there is no denial that prescription opioids can be misused, abused, and diverted, the policies have oversimplified the issue by curbing prescription opioids and the pendulum has swung too far in the direction of severely limiting prescription opioids, without acknowledgement that opioids have legitimate uses for persons suffering from chronic pain. Similar to the opioid crisis, interventional pain management procedures have been affected by various policies being applied to reduce overuse, abuse, and finally utilization. Medical policies have been becoming more restrictive with reduction of access to certain procedures, with the pendulum swinging too far in the direction of limiting interventional techniques. Recent utilization assessments have shown a consistent decline for most interventional techniques, with a 18.7% decrease from 2019 to 2020. The causes for these dynamic changes are multifactorial likely including the misapplication of the 2016 Centers for Disease Control and Prevention (CDC) guidelines for prescribing opioids for chronic pain, the relative ease of access to illicit synthetic opioids and more recently issues related to the COVID-19 pandemic. In addition, recent publications have shown association of dose tapering with overdose or mental health crisis among patients prescribed long-term opioids. These findings are leading to the hypothesis that federal guidelines may inadvertently be contributing to an increase in overall opioid deaths and diminished access to interventional techniques. Together, these have resulted in a fourth wave of the opioid epidemic., Methods: A narrative review., Results: The fourth wave results from a confluence of multiple factors, including misapplication of CDC guidelines, the increased availability of illicit drugs, the COVID-19 pandemic, and policies reducing access to interventional procedures. The CDC guidelines and subsequent regulatory atmosphere have led to aggressive tapering up to and including, at times, the overall reduction or stoppage of opioid prescriptions. Forced tapering has been linked to an increase of 69% for overdoses and 130% for mental health crisis. The data thus suggests that the diminution in access to opioid prescriptions may be occurring simultaneously with an increase in illicit narcotic use.Combined with CDC guidelines, the curbing of opioid prescriptions to medically needed individuals, among non-opioid treatments, interventional techniques have been affected with declining utilization rates and medical policies reducing access to such modalities., Conclusion: The opioid overdose waves over the past three decades have resulted from different etiologies. Wave one was associated with prescription opioid overdose deaths and wave two with the rise in heroin and overdose deaths from 1999 to 2013. Wave three was associated with a rise in synthetic opioid overdose deaths. Sadly, wave four continues to escalate with increasing number of deaths as a confluence of factors including the CDC guidelines, the COVID pandemic, increased availability of illicit synthetic opioids and the reduction of access to interventional techniques, which leads patients to seek remedies on their own.

Importance: Chronic pain is debilitating and profoundly affects health-related quality of life. Spinal cord stimulation (SCS) is a well-established therapy for chronic pain; however, SCS has been limited by the inability to directly measure the elicited neural response, precluding confirmation of neural activation and continuous therapy. A novel SCS system measures the evoked compound action potentials (ECAPs) to produce a real-time physiological closed-loop control system., Objective: To determine whether ECAP-controlled, closed-loop SCS is associated with better outcomes compared with fixed-output, open-loop SCS at 24 months following implant., Design, Setting, and Participants: The Evoke study was a double-blind, randomized, controlled, parallel arm clinical trial with 36 months of follow-up. Participants were enrolled from February 2017 to 2018, and the study was conducted at 13 US investigation sites. SCS candidates with chronic, intractable back and leg pain refractory to conservative therapy, who consented, were screened. Key eligibility criteria included overall, back, and leg pain visual analog scale score of 60 mm or more; Oswestry Disability Index score of 41 to 80; stable pain medications; and no previous SCS. Analysis took place from October 2020 to April 2021., Interventions: ECAP-controlled, closed-loop SCS was compared with fixed-output, open-loop SCS., Main Outcomes and Measures: Reported here are the 24-month outcomes of the trial, which include all randomized patients in the primary and safety analyses. The primary outcome was a reduction of 50% or more in overall back and leg pain assessed at 3 and 12 months (previously published)., Results: Of 134 randomized patients, 65 (48.5%) were female and the mean (SD) age was 55.2 (10.6) years. At 24 months, significantly more closed-loop than open-loop patients were responders (≥50% reduction) in overall pain (53 of 67 [79.1%] in the closed-loop group; 36 of 67 [53.7%] in the open-loop group; difference, 25.4% [95% CI, 10.0%-40.8%]; P = .001). There was no difference in safety profiles between groups (difference in rate of study-related adverse events: 6.0 [95% CI, -7.8 to 19.7]). Improvements were also observed in health-related quality of life, physical and emotional functioning, and sleep, in parallel with opioid reduction or elimination. Objective neurophysiological measurements substantiated the clinical outcomes and provided evidence of activation of inhibitory pain mechanisms., Conclusions and Relevance: ECAP-controlled, closed-loop SCS, which elicited a more consistent neural response, was associated with sustained superior pain relief at 24 months, consistent with the 3- and 12-month outcomes.

Objectives: ACCURATE, a randomized controlled trial, compared safety and effectiveness of stimulation of the dorsal root ganglion (DRG) vs. conventional spinal cord stimulation (SCS) in complex regional pain syndrome (CRPS-I and II) of the lower extremities. This analysis compares cost-effectiveness of three modalities of treatment for CRPS, namely DRG stimulation, SCS, and comprehensive medical management (CMM)., Materials and Methods: The retrospective cost-utility analysis combined ACCURATE study data with claims data to compare cost-effectiveness between DRG stimulation, SCS, and CMM. Cost-effectiveness was evaluated using a Markov cohort model with ten-year time horizon from the U.S. payer perspective. Incremental cost-effectiveness ratio (ICER) was reported as cost in 2017 U.S. dollars per gain in quality-adjusted life years (QALYs). Willingness-to-pay thresholds of $50,000/QALY and $100,000/QALY were used to define highly cost-effective and cost-effective therapies., Results: Both DRG and SCS provided an increase in QALYs (4.96 ± 1.54 and 4.58 ± 1.35 QALYs, respectively) and an increase in costs ($153,992 ± $36,651 and $128,269 ± $27,771, respectively) compared to CMM (3.58 ± 0.91 QALYs, $106,173 ± $27,005) over the ten-year model lifetime. Both DRG stimulation ($34,695 per QALY) and SCS ($22,084 per QALY) were cost-effective compared to CMM. In the base case, ICER for DRG v SCS was $68,095/QALY., Conclusions: DRG and SCS are cost-effective treatments for chronic pain secondary to CRPS-I and II compared to CMM. DRG accrued higher cost due to higher conversion from trial to permanent implant and shorter battery life, but DRG was the most beneficial therapy due to more patients receiving permanent implants and experiencing higher quality of life compared to SCS. New DRG technology has improved battery life, which we expect to make DRG more cost-effective compared to both CMM and SCS in the future., (© 2020 International Neuromodulation Society.)

Background: Spinal cord stimulation has been an established treatment for chronic back and leg pain for more than 50 years; however, outcomes are variable and unpredictable, and objective evidence of the mechanism of action is needed. A novel spinal cord stimulation system provides the first in vivo, real-time, continuous objective measure of spinal cord activation in response to therapy via recorded evoked compound action potentials (ECAPs) in patients during daily use. These ECAPs are also used to optimise programming and deliver closed-loop spinal cord stimulation by adjusting the stimulation current to maintain activation within patients' therapeutic window. We aimed to examine pain relief and the extent of spinal cord activation with ECAP-controlled closed-loop versus fixed-output, open-loop spinal cord stimulation for the treatment of chronic back and leg pain., Methods: This multicentre, double-blind, parallel-arm, randomised controlled trial was done at 13 specialist clinics, academic centres, and hospitals in the USA. Patients with chronic, intractable pain of the back and legs (Visual Analog Scale [VAS] pain score ≥60 mm; Oswestry Disability Index [ODI] score 41-80) who were refractory to conservative therapy, on stable pain medications, had no previous experience with spinal cord stimulation, and were appropriate candidates for a spinal cord stimulation trial were screened. Eligible patients were randomly assigned (1:1) to receive ECAP-controlled closed-loop spinal cord stimulation (investigational group) or fixed-output, open-loop spinal cord stimulation (control group). The randomisation sequence was computer generated with permuted blocks of size 4 and 6 and stratified by site. Patients, investigators, and site staff were masked to the treatment assignment. The primary outcome was the proportion of patients with a reduction of 50% or more in overall back and leg pain with no increase in pain medications. Non-inferiority (δ=10%) followed by superiority were tested in the intention-to-treat population at 3 months (primary analysis) and 12 months (additional prespecified analysis) after the permanent implant. This study is registered with ClinicalTrials.gov, NCT02924129, and is ongoing., Findings: Between Feb 21, 2017, and Feb 20, 2018, 134 patients were enrolled and randomly assigned (67 to each treatment group). The intention-to-treat analysis comprised 125 patients at 3 months (62 in the closed-loop group and 63 in the open-loop group) and 118 patients at 12 months (59 in the closed-loop group and 59 in the open-loop group). The primary outcome was achieved in a greater proportion of patients in the closed-loop group than in the open-loop group at 3 months (51 [82·3%] of 62 patients vs 38 [60·3%] of 63 patients; difference 21·9%, 95% CI 6·6-37·3; p=0·0052) and at 12 months (49 [83·1%] of 59 patients vs 36 [61·0%] of 59 patients; difference 22·0%, 6·3-37·7; p=0·0060). We observed no differences in safety profiles between the two groups. The most frequently reported study-related adverse events in both groups were lead migration (nine [7%] patients), implantable pulse generator pocket pain (five [4%]), and muscle spasm or cramp (three [2%])., Interpretation: ECAP-controlled closed-loop stimulation provided significantly greater and more clinically meaningful pain relief up to 12 months than open-loop spinal cord stimulation. Greater spinal cord activation seen in the closed-loop group suggests a mechanistic explanation for the superior results, which aligns with the putative mechanism of action for spinal cord stimulation and warrants further investigation., Funding: Saluda Medical., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Migraine is a debilitating condition that affects approximately 16% of adults and is the fifth leading cause of emergency department visits in the United States. There are several treatment options for migraines; opioids are frequently prescribed. Results from a recent study showed that more than half of the patients with chronic migraine and a third of the patients with episodic migraine received an opioid prescription in the past year. The American Headache Society recognizes the magnitude of this issue and is working to educate providers on the danger of prescribing opioids in the migraine population The objective of this article is to assess the utilization trends of prescription opioid products and evaluate the impact of opioid utilization on healthcare costs in this patient population. This retrospective claims database analysis used real-world medical claims from multiple health plans. The study period was from January 1, 2009, to September 30, 2017. Patients were included if they were 18 years or older and continuously enrolled in the study period for at least 3 years. Patients were included in the migraine cohort if they had any diagnosis of migraine headache during the study period, while patients without a headache related diagnosis were included in the control cohort. Control patients were propensity matched 1:1 to migraine patients. Discrete (count) data are represented by frequencies and percentages. Continuous results are presented as means, medians, and standard deviations. In the study, 107,216 patients met the inclusion criteria, with 53,608 assigned to each cohort. In the migraine and control cohorts, respectively, 28% and 11% were prescribed opioids. In both cohorts, a majority of the patients were female (81.8%). In both cohorts, opioid use was associated with higher total costs compared with patients who were not prescribed opioids: $82,007 for 200 morphine milligram equivalents (MME)/day or more versus $19,792 for no opioid in patients with migraine; and $54,200 for 200 MME/day or more versus $12,060 for no opioid use in control patients; P <.0001. Patients with more than 2 comorbidities who were prescribed opioids had higher costs than patients with more than 2 comorbidities who were not prescribed opioids and patients with less than 2 comorbidities who were prescribed opioids ($65,980, $32,152, and $35,964, respectively, for patients with migraine, and $52,883, $24,641, and $35,748, respectively, for control patients; P <.0001). Patients with migraine have more than twice the healthcare costs as patients without migraines. The additional increase in healthcare costs in patients with migraine who use opioids for treatment and/or have 2 or more comorbidities is significant. Control of the pain associated with migraine, specifically among those with multiple comorbid conditions, may contribute to substantial reductions in healthcare costs.

This study evaluates the impact of concomitant medical conditions on patients with and without migraine, assessing healthcare utilization, and total cost of care. Medical and pharmacy claims from multiple health plans, both nationally and internationally, were examined to evaluate overall real-world trends in commercially insured patients diagnosed with migraine. A total of 53,608 patients with diagnosis codes for migraine met the study criteria and were matched 1:1 with controls (81.8% female; mean age, 42 years; mean Charlson Comorbidity Index score, 0.34). During the 3-year measurement period, mean medical costs per patient in the migraine cohort were about 1.7 times that of the control group ($22,429 vs $13,166). Unique encounters and cost per patient by medical service type for the migraine cohort compared with the control group were as follows: emergency department, 4.13 ($4000) versus 2.94 ($2639); hospital inpatient, 3.15 ($17,748) versus 2.67 ($16,010); hospital outpatient, 5.14 ($365) versus 4.85 ($396); physician office, 36.78 ($6803) versus 21.39 ($4069); laboratory, 10.12 ($1433) versus 7.71 ($1057); radiology, 7.64 ($2609) versus 5.94 ($1733). Mean pharmacy costs per patient were approximately 1.8 times higher in the migraine cohort compared with the control cohort ($8441 vs $4588, respectively; P <.0001). These results suggest that patients with migraine have more comorbidities compared with those without migraine. These patients also utilize healthcare resources at a significantly higher rate compared with similar patients without a migraine diagnosis. An unmet need exists for new treatment modalities in this patient population. More effective interventions and proper management may lead to improved patient outcomes and healthcare costs for patients with migraine.

gammaCore is cleared by the FDA for acute and preventive treatment of cluster headache and the acute treatment of migraine in adults. Previously, only 2 treatments were approved for acute treatment of cluster headache while none were approved for preventive treatment. Following the initial FDA clearance, based on the ACT-1 and ACT-2 studies, a gammaCore Patient Registry (GPR) was designed to provide insights on the use of gammaCore and prescription patterns in the real-world setting and to characterize respective benefits and challenges during the acute treatment of episodic cluster headache. GPR was a prospective observational registry in which patients with episodic cluster headache (3rd edition of the International Classification of Headache Disorders criteria) who were prescribed gammaCore were invited to voluntarily enroll and provide information on their experiences between July 2017 and June 2018. Participants provided baseline information and were trained to self-administer treatment with gammaCore for cluster pain. Participants were also requested to record information for each cluster attack. Of the 182 patients who provided baseline demographic and cluster headache characteristics, 152 provided health index baseline data using EuroQol Health Index tool, 5-level format (EQ5D-5L) and 17 patients provided attack data on a total of 192 cluster headache attacks. The mean age was 49 years; 65% were male and 82% were white; the mean number of months of known diagnosis of cluster headache was 57; the mean number of attacks per cluster headache 4-week period was 14; and the mean pain score was 3.7 (0-4 scale) with a mean attack duration of 74 minutes. Sixty-seven percent of patients had used preventive treatments and 83% had used abortive treatments for cluster headaches; 25% of participants reported at least 1 comorbidity. The mean EQ5D-5L score (scale 0-1) was 0.83. Of the 192 cluster headache attacks reported, gammaCore was used in 116 (60%) attacks. Within this group, the mean pain score at the start of the attacks was 2.7, the mean number of stimulations used was 3.6, and the pain score after 30 minutes was 1.3. At 30 minutes, the pain of 81 (70%) attacks was reduced to none (27%) or mild (43%) (a pain score of 0 or 1) and in 94 (81%) attacks, patients experienced a reduction of at least 1 point in the pain score. This real-world observational evidence suggests that gammaCore adds clinically meaningful value to patients with episodic cluster headache by providing rapid pain relief and confirms that there is significant interest among prescribers in providing this new treatment and technology. This evidence further supports the need to redefine gammaCore as no longer investigational or experimental during considerations for reimbursement.

A patient audit was conducted in the UK to evaluate the impact of gammaCore use in multimorbidity patients on quality of life and healthcare resources utilization measures. A total of 233 patients were enrolled and their data was examined over a 1-year period after their gammaCore prescription. Of these patients, 132 (56%) had primary headache disorders while 101 (44%) were patients without a headache disorder (nonheadache patients). The mean age was 49 years, 169 (72%) were female, the mean number of comorbid conditions was 3.1, and the mean baseline EQ-5D score was 0.581. The mean paired difference in EQ-5D index for persistent gammaCore users (ie patients who used gammaCore for at least 40 weeks) was +0.156 at week 40. The mean percentage reductions in number of general practice consults (doctor's office appointments) was -28.5% from baseline mean of 7.31 and, 40.0% from baseline mean of 3.52 for medical codes used. This evidence demonstrates that a significant proportion of these multimorbidity patients on gammaCore remained compliant with the prescribed treatment regimen for an extended period. GammaCore use in multimorbidity patients may be associated with lower costs of care and provide opportunities for pay-for-performance coverage policies.

GammaCore was cleared by the FDA for the acute treatment of episodic migraine and episodic cluster headache and has 5 Conformité Européenne marks. Data indicate that gammaCore treatment is both safe and effective as an acute treatment for migraine. Current reimbursement policies need to be updated based on the growing body of evidence to reflect the established status of gammaCore that is no longer experimental. GammaCore provides substantial value to patients and to payers for consideration for pay-for-performance health coverage strategies and policies.

Migraine affects 15% of the population in the United States and is associated with comorbidities, with an estimated economic burden of $78 billion annually. GammaCore is used adjunctively with current standard of care and abortive medications and has shown to be superior in acute treatment of episodic migraine compared to sham. However, the economic impact has not been characterized for this indication. We conducted a cost-effectiveness analyses for 2 hypothetical scenarios: a primary model for treatment options gammaCore plus standard of care compared to standard of care alone for acute treatment of migraine; and a secondary model for treatment sequence strategies where acute treatment with gammaCore or standard of care each prior to erenumab prevention compared to initiating erenumab prevention with no prerequisite. The time horizon for the model is 1 year, using a payer perspective. GammaCore plus standard of care arm was dominant over standard of care alone in the primary model. The mean costs for gammaCore plus standard of care arm and standard of care individually were $9678 and $10,010, respectively. The mean quality of life-years for gammaCore plus standard of care arm and standard of care alone were 0.67, and 0.63, respectively. For the secondary model, the mean costs for gammaCore followed by erenumab, standard of care followed by erenumab and initiating with erenumab with no prior gammaCore or standard of care treatment were $10,678, $11,583, and $13,766. The corresponding mean for quality of life-years were 0.70, 0.67, and 0.65, respectively. For gammaCore dominance, ie, in this scenario, patients were more satisfied on gammaCore, to not need erenumab for preventative therapy lower mean costs and represents savings for payers. This was driven by efficacy, improvement in quality of life, and reduction in costs of care associated with successful treatment of migraine attacks. These findings provide new economic evidence to support value forcoverage for gammaCore.

Background and Objectives: This study evaluated the long-term durability of the minimally invasive lumbar decompression (MILD) procedure in terms of functional improvement and pain reduction for patients with lumbar spinal stenosis and neurogenic claudication due to hypertrophic ligamentum flavum. This is a report of 2-year follow-up for MILD study patients., Methods: This prospective, multicenter, randomized controlled clinical study compared outcomes for 143 patients treated with MILD versus 131 treated with epidural steroid injections. Follow-up occurred at 6 months and at 1 year for the randomized phase and at 2 years for MILD subjects only. Oswestry Disability Index, Numeric Pain Rating Scale, and Zurich Claudication Questionnaire were used to evaluate function and pain. Safety was evaluated by assessing incidence of device-/procedure-related adverse events., Results: All outcome measures demonstrated clinically meaningful and statistically significant improvement from baseline through 6-month, 1-year, and 2-year follow-ups. At 2 years, Oswestry Disability Index improved by 22.7 points, Numeric Pain Rating Scale improved by 3.6 points, and Zurich Claudication Questionnaire symptom severity and physical function domains improved by 1.0 and 0.8 points, respectively. There were no serious device-/procedure-related adverse events, and 1.3% experienced a device-/procedure-related adverse event., Conclusions: MILD showed excellent long-term durability, and there was no evidence of spinal instability through 2-year follow-up. Reoperation and spinal fracture rates are lower, and safety is higher for MILD versus other lumbar spine interventions, including interspinous spacers, surgical decompression, and spinal fusion. Given the minimally invasive nature of this procedure, its robust success rate, and durability of outcomes, MILD is an excellent choice for first-line therapy for select patients with central spinal stenosis suffering from neurogenic claudication symptoms with hypertrophic ligamentum flavum., Clinical Trial Registration: This study was registered at ClinicalTrials.gov, identifier NCT02093520.

Study Design: A review of the literature evaluating clinical trials of chronic back pain., Objective: To assist physicians in assessing the quality of clinical trial data to make the most informed treatment decisions., Summary of Background Data: Chronic pain is a tremendous public health issue, affecting close to 100 million adults in the United States, and costs the American people billions of dollars. One traditional treatment approach, the long-term use of opiate medications, has recently come under intense scrutiny for problems with complications, diversion, abuse, addiction, and lack of efficacy. In addition, the Centers for Disease Control and Prevention has recognized that overprescribing opiates has enabled an overdose crisis, and written guidelines that are intended to limit their use. It is for this reason that physicians must have a comprehensive understanding of the range of drug-free alternative therapies available and have the tools needed to rigorously evaluate the chronic pain literature so they can make appropriate treatment decisions., Methods: An evaluation of how clinical trials are designed and ranked, outcome measures, and costs for a variety of therapies is necessary to determine which treatment option is the most efficacious for an individual patient., Results: Clinical trial data demonstrate that spinal cord stimulation (SCS) is a safe and effective treatment option for many types of chronic pain, including back pain. The last 10 years has brought tremendous advances in the field of neuromodulation. Today, several treatment modalities exist for SCS requiring the physician to be able to critically evaluate and interpret the literature and determine which modality has the strongest evidence. When evaluating clinical trial data of patients with chronic back pain, emphasis must be placed on well designed, randomized controlled trials with long-term follow-up producing level I evidence. These data are obtained in a rigorous manner and are likely to have less bias when compared with lower level studies., Conclusion: The level I studies performed to date have provided evidence that treatment with SCS results in sustainable pain reduction and improvements in scores measuring quality of life and patient functioning in those patients with chronic intractable back pain., Level of Evidence: 5.

Background: Opioid use, abuse, and adverse consequences, including death, have escalated at an alarming rate since the 1990s. In an attempt to control opioid abuse, numerous regulations and guidelines for responsible opioid prescribing have been developed by various organizations. However, the US opioid epidemic is continuing and drug dose deaths tripled during 1999 to 2015. Recent data show a continuing increase in deaths due to natural and semisynthetic opioids, a decline in methadone deaths, and an explosive increase in the rates of deaths involving other opioids, specifically heroin and illicit synthetic fentanyl. Contrary to scientific evidence of efficacy and negative recommendations, a significant proportion of physicians and patients (92%) believe that opioids reduce pain and a smaller proportion (57%) report better quality of life. In preparation of the current guidelines, we have focused on the means to reduce the abuse and diversion of opioids without jeopardizing access for those patients suffering from non-cancer pain who have an appropriate medical indication for opioid use., Objectives: To provide guidance for the prescription of opioids for the management of chronic non-cancer pain, to develop a consistent philosophy among the many diverse groups with an interest in opioid use as to how appropriately prescribe opioids, to improve the treatment of chronic non-cancer pain and to reduce the likelihood of drug abuse and diversion. These guidelines are intended to provide a systematic and standardized approach to this complex and difficult arena of practice, while recognizing that every clinical situation is unique., Methods: The methodology utilized included the development of objectives and key questions. The methodology also utilized trustworthy standards, appropriate disclosures of conflicts of interest, as well as a panel of experts from various specialties and groups. The literature pertaining to opioid use, abuse, effectiveness, and adverse consequences was reviewed, with a best evidence synthesis of the available literature, and utilized grading for recommendation as described by the Agency for Healthcare Research and Quality (AHRQ).Summary of Recommendations:i. Initial Steps of Opioid Therapy 1. Comprehensive assessment and documentation. (Evidence: Level I; Strength of Recommendation: Strong) 2. Screening for opioid abuse to identify opioid abusers. (Evidence: Level II-III; Strength of Recommendation: Moderate) 3. Utilization of prescription drug monitoring programs (PDMPs). (Evidence: Level I-II; Strength of Recommendation: Moderate to strong) 4. Utilization of urine drug testing (UDT). (Evidence: Level II; Strength of Recommendation: Moderate) 5. Establish appropriate physical diagnosis and psychological diagnosis if available. (Evidence: Level I; Strength of Recommendation: Strong) 6. Consider appropriate imaging, physical diagnosis, and psychological status to collaborate with subjective complaints. (Evidence: Level III; Strength of Recommendation: Moderate) 7. Establish medical necessity based on average moderate to severe (≥ 4 on a scale of 0 - 10) pain and/or disability. (Evidence: Level II; Strength of Recommendation: Moderate) 8. Stratify patients based on risk. (Evidence: Level I-II; Strength of Recommendation: Moderate) 9. Establish treatment goals of opioid therapy with regard to pain relief and improvement in function. (Evidence: Level I-II; Strength of Recommendation: Moderate) 10. Obtain a robust opioid agreement, which is followed by all parties. (Evidence: Level III; Strength of Recommendation: Moderate)ii. Assessment of Effectiveness of Long-Term Opioid Therapy 11. Initiate opioid therapy with low dose, short-acting drugs, with appropriate monitoring. (Evidence: Level II; Strength of Recommendation: Moderate) 12. Consider up to 40 morphine milligram equivalent (MME) as low dose, 41 to 90 MME as a moderate dose, and greater than 91 MME as high dose. (Evidence: Level II; Strength of Recommendation: Moderate) 13. Avoid long-acting opioids for the initiation of opioid therapy. (Evidence: Level I; Strength of Recommendation: Strong) 14. Recommend methadone only for use after failure of other opioid therapy and only by clinicians with specific training in its risks and uses, within FDA recommended doses. (Evidence: Level I; Strength of Recommendation: Strong) 15. Understand and educate the patients of the effectiveness and adverse consequences. (Evidence: Level I; Strength of Recommendation: Strong) 16. Similar effectiveness for long-acting and short-acting opioids with increased adverse consequences of long-acting opioids. (Evidence: Level I-II; Strength of recommendation: Moderate to strong) 17. Periodically assess pain relief and/or functional status improvement of ≥ 30% without adverse consequences. (Evidence: Level II; Strength of recommendation: Moderate) 18. Recommend long-acting or high dose opioids only in specific circumstances with severe intractable pain. (Evidence: Level I; Strength of Recommendation: Strong)iii. Monitoring for Adherence and Side Effects 19. Monitor for adherence, abuse, and noncompliance by UDT and PDMPs. (Evidence: Level I-II; Strength of Recommendation: Moderate to strong) 20. Monitor patients on methadone with an electrocardiogram periodically. (Evidence: Level I; Strength of Recommendation: Strong). 21. Monitor for side effects including constipation and manage them appropriately, including discontinuation of opioids when indicated. (Evidence: Level I; Strength of Recommendation: Strong)iv. Final Phase 22. May continue with monitoring with continued medical necessity, with appropriate outcomes. (Evidence: Level I-II; Strength of Recommendation: Moderate) 23. Discontinue opioid therapy for lack of response, adverse consequences, and abuse with rehabilitation. (Evidence: Level III; Strength of Recommendation: Moderate) CONCLUSIONS: These guidelines were developed based on comprehensive review of the literature, consensus among the panelists, in consonance with patient preferences, shared decision-making, and practice patterns with limited evidence, based on randomized controlled trials (RCTs) to improve pain and function in chronic non-cancer pain on a long-term basis. Consequently, chronic opioid therapy should be provided only to patients with proven medical necessity and stability with improvement in pain and function, independently or in conjunction with other modalities of treatments in low doses with appropriate adherence monitoring and understanding of adverse events.Key words: Chronic pain, persistent pain, non-cancer pain, controlled substances, substance abuse, prescription drug abuse, dependency, opioids, prescription monitoring, drug testing, adherence monitoring, diversionDisclaimer: The guidelines are based on the best available evidence and do not constitute inflexible treatment recommendations. Due to the changing body of evidence, this document is not intended to be a "standard of care."

Background: Lumbar spinal stenosis (LSS) is a common degenerative condition of the spine, which is a major cause of pain and functional disability for the elderly. Neurogenic claudication symptoms are a hallmark of LSS, where patients develop low back or leg pain when walking or standing that is relieved by sitting or lumbar flexion. The treatment of LSS generally begins with conservative management such as physical therapy, home exercise programs, and oral analgesics. Once these therapies fail, patients commonly move forward with interventional pain treatment options such as epidural steroid injections (ESIs) or MILD® as the next step., Objective: To assess improvement of function and reduction in pain for Medicare beneficiaries following treatment with MILD (treatment group) in LSS patients with neurogenic claudication and verified ligamentum flavum hypertrophy and to compare to a control group receiving ESIs., Study Design: Prospective, multi-center, randomized controlled clinical trial., Setting: Twenty-six US interventional pain management centers., Methods: Patients in this trial were randomized one to one into 2 study arms. A total of 302 patients were enrolled, with 149 randomized to MILD and 153 to the active control. Outcomes are assessed using the Oswestry Disability Index (ODI), Numeric Pain Rating Scale (NPRS) and Zurich Claudication Questionnaire (ZCQ). Primary efficacy is the proportion of ODI responders, tested for statistical superiority of the MILD group versus the ESI group. ODI responders are defined as patients achieving the validated Minimal Important Change (MIC) of = 10 point improvement in ODI from baseline to follow-up. Similarly, secondary efficacy is the proportion of NPRS and ZCQ responders using validated MIC thresholds. Primary safety is the incidence of device- or procedure-related adverse events in each group. This report presents safety and efficacy results at 1-year follow-up. Outcomes at 2 years will be collected and reported for patients in the MILD group only., Results: At 1-year follow-up, ODI, NPRS, and all 3 ZCQ domains (Symptom Severity, Physical Function and Patient Satisfaction) demonstrated statistically significant superiority of MILD versus the active control. For primary efficacy, the 58.0% ODI responder rate in the MILD group was higher than the 27.1% responder rate in the epidural steroid group (P < 0.001). The primary safety endpoint was achieved, demonstrating that there is no difference in safety between MILD and ESIs (P = 1.00)., Limitations: There was a lack of patient blinding due to considerable differences in treatment protocols, and a potentially higher non-responder rate for both groups versus standard-of-care due to adjunctive pain therapy study restrictions. Study enrollment was not limited to patients that had never received ESI therapy., Conclusions: One-year results of this randomized controlled clinical trial demonstrate that MILD is statistically superior to ESIs in the treatment of LSS patients with neurogenic claudication and verified central stenosis due to ligamentum flavum hypertrophy. Primary and secondary efficacy outcome measures achieved statistical superiority in the MILD group compared to the control group. With 95% of patients in this study presenting with 5 or more LSS co-factors, it is important to note that patients with spinal co-morbidities also experienced statistically significant improved function that was durable through 1 year., Key Words: MILD, minimally invasive lumbar decompression, interlaminar epidural steroid injections, ESI neurogenic claudication, ligamentum flavum, ENCORE, PILD, CED Study, LSS.

Background: Patients suffering from neurogenic claudication due to lumbar spinal stenosis (LSS) often experience moderate to severe pain and significant functional disability. Neurogenic claudication results from progressive degenerative changes in the spine, and most often affects the elderly. Both the MILD® procedure and epidural steroid injections (ESIs) offer interventional pain treatment options for LSS patients experiencing neurogenic claudication refractory to more conservative therapies. MILD provides an alternative to ESIs via minimally invasive lumbar decompression., Study Design: Prospective, multi-center, randomized controlled clinical trial., Setting: Twenty-six US interventional pain management centers., Objective: To compare patient outcomes following treatment with either MILD (treatment group) or ESIs (active control group) in LSS patients with neurogenic claudication and verified ligamentum flavum hypertrophy., Methods: This prospective, multi-center, randomized controlled clinical trial includes 2 study arms with a 1-to-1 randomization ratio. A total of 302 patients were enrolled, with 149 randomized to MILD and 153 to the active control. Six-month follow-up has been completed and is presented in this report. In addition, one year follow-up will be conducted for patients in both study arms, and supplementary 2 year outcome data will be collected for patients in the MILD group only., Outcome Measures: Outcomes are assessed using the Oswestry Disability Index (ODI), numeric pain rating scale (NPRS) and Zurich Claudication Questionnaire (ZCQ). Primary efficacy is the proportion of ODI responders, tested for statistical superiority of the MILD group versus the active control group. ODI responders are defined as patients achieving the validated Minimal Important Change (MIC) of =10 point improvement in ODI from baseline to follow-up. Similarly, secondary efficacy includes proportion of NPRS and ZCQ responders using validated MIC thresholds. Primary safety is the incidence of device or procedure-related adverse events in each group., Results: At 6 months, all primary and secondary efficacy results provided statistically significant evidence that MILD is superior to the active control. For primary efficacy, the proportion of ODI responders in the MILD group (62.2%) was statistically significantly higher than for the epidural steroid group (35.7%) (P < 0.001). Further, all secondary efficacy parameters demonstrated statistical superiority of MILD versus the active control. The primary safety endpoint was achieved, demonstrating that there is no difference in safety between MILD and ESIs (P = 1.00)., Limitations: Limitations include lack of patient blinding due to considerable differences in treatment protocols, and a potentially higher non-responder rate for both groups versus standard-of-care due to study restrictions on adjunctive pain therapies., Conclusions: Six month follow-up data from this trial demonstrate that the MILD procedure is statistically superior to epidural steroids, a known active treatment for LSS patients with neurogenic claudication and verified central stenosis due to ligamentum flavum hypertrophy. The results of all primary and secondary efficacy outcome measures achieved statistically superior outcomes in the MILD group versus ESIs. Further, there were no statistically significant differences in the safety profile between study groups. This prospective, multi-center, randomized controlled clinical trial provides strong evidence of the effectiveness of MILD versus epidural steroids in this patient population., Clinical Trial Registration: NCT02093520.

Background: Epidural injections have been used since 1901 in managing low back pain and sciatica. Spinal pain, disability, health, and economic impact continue to increase, despite numerous modalities of interventions available in managing chronic spinal pain. Thus far, systematic reviews performed to assess the efficacy of epidural injections in managing chronic spinal pain have yielded conflicting results., Objective: To evaluate and update the clinical utility of the efficacy of epidural injections in managing chronic spinal pain., Study Design: A systematic review of randomized controlled trials of epidural injections in managing chronic spinal pain., Methods: In this systematic review, randomized trials with a placebo control or an active-control design were included. The outcome measures were pain relief and functional status improvement. The quality of each individual article was assessed by Cochrane review criteria, as well as the Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB). Best evidence synthesis was conducted based on the qualitative level of evidence (Level I to V). Data sources included relevant literature identified through searches of PubMed for a period starting in 1966 through August 2015; Cochrane reviews; and manual searches of the bibliographies of known primary and review articles., Results: A total of 52 trials met inclusion criteria. Meta-analysis was not feasible. The evidence in managing lumbar disc herniation or radiculitis is Level II for long-term improvement either with caudal, interlaminar, or transforaminal epidural injections with no significant difference among the approaches. The evidence is Level II for long-term management of cervical disc herniation with interlaminar epidural injections. The evidence is Level II to III in managing thoracic disc herniation with an interlaminar approach. The evidence is Level II for caudal and lumbar interlaminar epidural injections with Level III evidence for lumbar transforaminal epidural injections for lumbar spinal stenosis. The evidence is Level III for cervical spinal stenosis management with an interlaminar approach. The evidence is Level II for axial or discogenic pain without facet arthropathy or disc herniation treated with caudal or lumbar interlaminar injections in the lumbar region; whereas it is Level III in the cervical region treated with cervical interlaminar epidural injections. The evidence for post lumbar surgery syndrome is Level II with caudal epidural injections and for post cervical surgery syndrome it is Level III with cervical interlaminar epidural injections., Limitations: Even though this is a large systematic review with inclusion of a large number of randomized controlled trials, the paucity of high quality randomized trials literature continues to confound the evidence., Conclusion: This systematic review, with an assessment of the quality of manuscripts and outcome parameters, shows the efficacy of epidural injections in managing a multitude of chronic spinal conditions.

Background: The sacroiliac joint is well known as a cause of low back and lower extremity pain. Prevalence estimates are 10% to 25% in patients with persistent axial low back pain without disc herniation, discogenic pain, or radiculitis based on multiple diagnostic studies and systematic reviews. However, at present there are no definitive management options for treating sacroiliac joint pain., Objective: To evaluate the diagnostic accuracy and therapeutic effectiveness of sacroiliac joint interventions., Study Design: A systematic review of the diagnostic accuracy and therapeutic effectiveness of sacroiliac joint interventions., Methods: The available literature on diagnostic and therapeutic sacroiliac joint interventions was reviewed. The quality assessment criteria utilized were the Quality Appraisal of Reliability Studies (QAREL) checklist for diagnostic accuracy studies, Cochrane review criteria to assess sources of risk of bias, and Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB) criteria for randomized therapeutic trials and Interventional Pain Management Techniques-Quality Appraisal of Reliability and Risk of Bias Assessment for Nonrandomized Studies (IPM-QRBNR) for observational therapeutic assessments. The level of evidence was based on a best evidence synthesis with modified grading of qualitative evidence from Level I to Level V. Data sources included relevant literature published from 1966 through March 2015 that were identified through searches of PubMed and EMBASE, manual searches of the bibliographies of known primary and review articles, and all other sources., Outcome Measures: For the diagnostic accuracy assessment, and for the therapeutic modalities, the primary outcome measure of pain relief and improvement in functional status were utilized., Results: A total of 11 diagnostic accuracy studies and 14 therapeutic studies were included. The evidence for diagnostic accuracy is Level II for dual diagnostic blocks with at least 70% pain relief as the criterion standard and Level III evidence for single diagnostic blocks with at least 75% pain relief as the criterion standard. The evidence for cooled radiofrequency neurotomy in managing sacroiliac joint pain is Level II to III. The evidence for conventional radiofrequency neurotomy, intraarticular steroid injections, and periarticular injections with steroids or botulinum toxin is limited: Level III or IV., Limitations: The limitations of this systematic review include inconsistencies in diagnostic accuracy studies with a paucity of high quality, replicative, and consistent literature. The limitations for therapeutic interventions include variations in technique, variable diagnostic standards for inclusion criteria, and variable results., Conclusion: The evidence for the accuracy of diagnostic and therapeutic effectiveness of sacroiliac joint interventions varied from Level II to Level IV.

Background: Epidural steroid injections (ESIs) are commonly used for treatment of symptomatic lumbar spinal stenosis (LSS). ESIs are generally administered after failure of conservative therapy. For LSS patients suffering from neurogenic claudication, the mild® procedure provides an alternative to ESIs via minimally invasive lumbar decompression. Both ESIs and mild offer interventional pain treatment options for LSS patients experiencing neurogenic claudication refractory to more conservative therapies., Study Design: Prospective, multi-center, randomized controlled, clinical study., Setting: Twenty-six interventional pain management centers throughout the United States., Objective: To compare patient outcomes following treatment with either mild or ESIs in LSS patients with neurogenic claudication and having verified ligamentum flavum hypertrophy., Methods: Study participants include Medicare beneficiaries who meet study inclusion/exclusion criteria. Eligible patients will be randomized in a 1:1 ratio to one of 2 treatment arms, mild (treatment group) or ESI (control group). Each study group will include approximately 150 patients who have experienced neurogenic claudication symptoms for ≥ 3 months duration who have failed to respond to physical therapy, home exercise programs, and oral analgesics. Those randomized to mild are prohibited from receiving lumbar ESIs during the study period, while those randomized to ESI may receive ESIs up to 4 times per year. Patient assessments will occur at baseline, 6 months, and one year. An additional assessment will be conducted for the mild patient group at 2 years., Outcome Measures: The primary efficacy outcome measure is the proportion of Oswestry Disability Index (ODI) responders from baseline to one year follow-up in the treatment group (mild) versus the control group (ESI). ODI responders are defined as those patients achieving the validated Minimal Important Change (MIC) of ≥ 10 point improvement in ODI from baseline to follow-up as a clinically significant efficacy threshold. Secondary efficacy outcome measures include the proportion of Zurich Claudication Questionnaire (ZCQ) and Numeric Pain Rating Scale (NPRS) responders from baseline to follow-up using validated MIC thresholds. Improvement in ZCQ domains of ≥ 0.5 is considered significant, and a Patient Satisfaction score of at least 2.5 represents a satisfied patient. A reduction of ≥ 2 points in NPRS is considered significant pain relief. The primary safety outcome measure is the incidence of device- and/or procedure-related adverse events., Results: Descriptive summaries will be presented by randomized group for all outcome measures at baseline and follow-up time points. Inferential statistical analysis will be conducted to determine significant differences related to functional improvement, pain relief, and safety outcomes. Primary study results will be presented based on one-year follow-up data, with an interim analysis report when 6-month follow-up data become available., Limitations: Patients are not blinded due to significant differences in treatment protocols between study groups. Also, since neither study arm is focused on treatment of radicular pain, there may be a higher non-responder rate for both groups versus standard of care due to study restrictions on adjunctive pain therapies., Conclusions: This prospective, multi-center, randomized controlled study will provide Level I evidence of the safety and effectiveness of mild versus ESIs in managing neurogenic claudication symptoms in LSS patients.