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Schuster, Nathaniel M.

https://orcid.org/0000-0002-4970-6296

Mayo Clinic

UC San Diego Health System

Citations 9

Response to LTE: CMS proposed restrictions on peripheral nerve blocks and procedures for chronic pain: clinical, ethical, and policy implications for millions of Americans
Singla, Priyanka, Adler, Alexandra, Babington, James R., McCormick, Zachary L, Osborne, Michael D. , Barreveld, Antje M. , Singla, Priyanka , Singla, Priyanka , Schuster, Nathaniel M.

Pain Medicine | April 4, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1093/pm/pnag051 Get It

Debunking myths in facial pain diagnosis for the pain practitioner
Schuster, Nathaniel M. , Argoff, Charles E. , Barad, Meredith , Kesayan, Tigran , Kissoon, N., Narouze, Samer , Qian, Xiang , Romero-Reyes, Marcela, Yuan, Hsiangkuo , Narouze, Samer , Schuster, Nathaniel M , Barad, Meredith J , Yuan, Hsiangkuo , Kissoon, Narayan , Romero‐Reyes, Marcela

Regional Anesthesia & Pain Medicine | January 8, 2026 | Volume: No volume available | Issue: No issue available | Pages: rapm-2025-107382

10.1136/rapm-2025-107382 Get It

Facial pain disorders, most notoriously trigeminal neuralgia, cause substantial suffering, functional impairment, disability, and impaired quality of life. However, most pain medicine practitioners have had only limited education on the evaluation, diagnosis, and treatment of facial pain. Furthermore, this limited education often contains commonly held myths about facial pain diagnosis. These myths can result in misdiagnoses that lead to ineffective medications, interventions, or surgeries and prolonged pain. Therefore, the American Society of Regional Anesthesia and Pain Medicine’s Headache and Facial Pain Special Interest Group convened a multidisciplinary group of neurologists, anesthesiologists, and dentists to identify and dispel pervasive myths in facial pain diagnosis.
Consensus practice guidelines on sacroiliac joint complex pain from a multispecialty, international working group
McCormick, Zachary L. , Hurley, Robert W. , Anițescu, Magdalena , Bhaskar, Arun , Cassidy, R. Carter , Chen, Allen S. , Dawson, Timothy , Campos, José Luiz de, Hernández-Porras, Berenice Carolina , Kohan, Lynn , Reece, Ltc David E, Smith, Clark C, Stout, Alison , Szadek, Karolina M., Thomas, Donna-Ann, Tontisirin, Nuj , Vagg, Michael, Hurley, Robert W , Tontisirin, Nuj , Bhaskar, Arun, Bhatia, Anuj , Ares, Javier De Andrés , Hayek, Salim M. , Kissoon, Narayan , Elgueta Le Beuffe, María Francisca , Moon, Jee Youn , Provenzano, David , Schuster, Nathaniel M. , Smith, Clark, Zundert, Jan Van , Woodbury, Anna , Cohen, Steven P.

Regional Anesthesia & Pain Medicine | December 14, 2025 | Volume: No volume available | Issue: No issue available | Pages: rapm-2025-107387

10.1136/rapm-2025-107387 Get It

Background The past two decades have witnessed tremendous growth in the appreciation and treatment of sacroiliac joint (SIJ) complex pain, including anatomical dissections that shed light on innervation, an appreciation for the contribution of extra-articular components to SIJ complex pain, the advent of radiofrequency ablation (RFA) and a host of minimally-invasive surgical techniques. Yet, there is no standardization of diagnosis and treatment paradigms. Methods In February 2023, the Boards of Directors for the American Academy of Pain Medicine (AAPM) and American Society of Regional Anesthesia & Pain Medicine (ASRA-PM) approved the development of multispecialty guidelines on SIJ complex pain. Thirty partner organizations with clinical and scientific interests in SIJ complex pain were identified, and formal letters of request-for-participation were sent to each, along with a request for nominees to serve on the committee. Twenty five organizations agreed to participate in addition to the Departments of Defense and Veterans Affairs. A steering committee developed 21 questions, which spanned criteria for diagnosis, non-interventional and interventional treatments including surgery, technical parameters on how to optimize results, and what constitutes positive outcomes. Questions were methodically assigned to specialized modules comprising 4–5 members with complementary expertise, who collaborated with the Subcommittee Lead and one of three Committee Chairs to develop preliminary drafts. Following thorough revisions, these drafts were subsequently submitted to the full committee for comprehensive review. A modified Delphi method was used in which the answers to questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was achieved. During a committee meeting before commencement, it was agreed that recommendations would be noted when there was >50% agreement among committee members, but that a formal recommendation would require ≥75% consensus. Results Twenty-one organizations formally endorsed the guidelines. The American Society of Anesthesiologists, and American Academy of Physical Medicine & Rehabilitation, and the North American Spine Society affirmed the benefit of the guidelines but did not officially endorse them. The American Academy of Neurology declined to affirm the benefit of the guidelines citing ‘lack of relevance to their membership.’ Per policies, while the Departments of Defense and Veterans Affairs did not formally review the guidelines for endorsement, their representatives approved them. In addition to being endorsed or the benefit affirmed by all voting organizations, complete consensus from committee members was obtained on all 21 questions. On two recommendations, there were dissensions from three societies who thought that selecting patients for sacral lateral branch RFA and minimally-invasive fusion should be based on ≥75% relief from two blocks instead of at least 50% relief from a single block before RFA, and greater than 50% pain relief with documented functional improvement after a single block before fusion. One additional society (Latin American Society of Regional Anesthesia) abstained on the statement that the evidence is stronger for extra-articular than intra-articular injections. The committee found that a battery of physical exam tests has reasonable sensitivity, but lower specificity, for identifying intra-articular but not extra-articular pain, with negative tests having greater predictive value than positive ones. Intra-articular injections have diagnostic validity for SIJ intra-articular, but not extra-articular, pain. There is unclear or negative evidence for imaging. The prevalence rates of intra-articular and extra-articular pathology are comparable, with both intra- and extra-articular steroid injections providing at least 4 weeks of relief in well-selected patients. However, the evidence is slightly stronger for extra-articular corticosteroid injections to provide short-term relief. The evidence base for non-interventional therapies is indirect, extrapolated mostly from low back pain studies. There is weak evidence supporting dextrose-based prolotherapy and platelet-rich plasma to provide at least 3 months of pain relief. There is strong evidence for sacral lateral branch RFA to provide relief for at least 6 months in individuals with extra-articular pathology, with face validity and indirect evidence from randomized trials supporting sacral lateral branch blocks as a prognostic tool. There is stronger evidence for larger lesions or more aggressive lesioning strategies than for less stringent techniques. There is weak evidence to support non-steroidal anti-inflammatory drugs to prevent neuritis after RFA, and in most cases anticoagulation does not require cessation in the periprocedural period. With an aggressive lesioning strategy, sensory stimulation provides minimal therapeutic benefit, with weak, extrapolated evidence that motor stimulation can provide safety benefit. The cut-off to designate diagnostic or prognostic blocks as positive is most commonly set at 50%, with higher values not shown to improve outcomes for more definitive procedures; for therapeutic treatment outcomes, the evidence supports a lower threshold of ≥30% pain relief or meaningful benefit on non-pain outcomes (eg, opioid cessation) for designation of a positive response. For carefully selected patients with intra-articular SIJ complex pain based on controlled blocks who have failed conservative therapies, there is weak or very weak evidence that minimally invasive SIJ fusion can provide benefit for at least one year. Conclusions SIJ complex pain remains an underappreciated source of chronic low back pain, affecting between 15% and 30% of patients with axial pain predominantly below L5. Answers to many questions were limited by low-quality evidence, indicating the need for better research. SIJ complex pain is a multifarious condition (ie, pain can be from different portions of both the intra- and extra-articular components of the joint) for which an interdisciplinary, multimodal treatment plan can optimize treatment outcomes.
Consensus practice guidelines on sacroiliac joint complex pain from a multispecialty, international working group
McCormick, Zachary L. , Hurley, Robert W. , Anițescu, Magdalena , Bhaskar, Arun , Bhatia, Anuj , Cassidy, R. Carter , Chen, Allen S. , Dawson, Timothy , Ares, Javier De Andrés , Campos, José Luiz de, Hernández-Porras, Berenice Carolina , Kohan, Lynn , Reece, David , Smith, Clark C, Stout, Alison , Szadek, Karolina M., Thomas, Donna-Ann, Tontisirin, Nuj , Vagg, Michael, Zundert, Jan Van , Woodbury, Anna , Cassidy, Ryan Carter , De Andrés Ares, Javier , Hayek, Salim , Kissoon, Narayan R , Kohan, Lynn R , Elgueta Le Beuffe, María Francisca , Moon, Jee Youn , Provenzano, David Anthony , Schuster, Nathaniel M , Stout, Alison , Tontisirin, Nuj , van Zundert, Jan , Woodbury, Anna , Cohen, Steven P , Hurley, Robert W , Bhatia, Anuj , Bhaskar, Arun, Hayek, Salim M. , Kissoon, Narayan , Provenzano, David , Schuster, Nathaniel M. , Smith, Clark, Cohen, Steven P.

Pain Medicine | September 18, 2025 | Volume: 26 | Issue: 12 | Pages: 817-917

10.1093/pm/pnaf129 Get It

Abstract Background The past two decades have witnessed tremendous growth in the appreciation and treatment of sacroiliac joint (SIJ) complex pain, including anatomical dissections that shed light on innervation, an appreciation for the contribution of extra-articular components to SIJ complex pain, the advent of radiofrequency ablation (RFA) and a host of minimally invasive surgical techniques. Yet, there is no standardization on diagnosis and treatment paradigms. Methods In February 2023, the Boards of Directors for the American Academy of Pain Medicine (AAPM) and American Society of Regional Anesthesia & Pain Medicine (ASRA-PM) approved the development of multispecialty guidelines on SIJ complex pain. Thirty partner organizations with clinical and scientific interests in SIJ complex pain were identified, and formal letters of request-for-participation were sent to each, along with a request for nominees to serve on the committee. Twenty five organizations agreed to participate in addition to the Departments of Defense and Veterans Affairs. A steering committee developed 21 questions, which spanned criteria for diagnosis, non-interventional and interventional treatments including surgery, technical parameters on how to optimize results, and what constitutes positive outcomes. Questions were methodically assigned to specialized modules comprising 4-5 members with complementary expertise, who collaborated with the Subcommittee Lead and one of three Committee Chairs to develop preliminary drafts. Following thorough revisions, these drafts were subsequently submitted to the full committee for comprehensive review. A modified Delphi method was used in which the answers to questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was achieved. During a committee meeting before commencement, it was agreed that recommendations would be noted when there was >50% agreement among committee members, but that a formal recommendation would require ≥75% consensus. Results Twenty-one organizations formally endorsed the guidelines. The American Society of Anesthesiologists, and American Academy of Physical Medicine & Rehabilitation, and the North American Spine Society affirmed the benefit of the guidelines but did not officially endorse them. The American Academy of Neurology declined to affirm the benefit of the guidelines citing “lack of relevance to their membership.” Per policies, while the Departments of Defense and Veterans Affairs did not formally review the guidelines for endorsement, their representatives approved them. In addition to being endorsed or the benefit affirmed by all voting organizations, complete consensus from committee members was obtained on all 21 questions. On 2 recommendations, there were dissensions from 3 societies who thought that selecting patients for sacral lateral branch RFA and minimally invasive fusion should be based on ≥75% relief from 2 blocks instead of at least 50% relief from a single block before RFA, and greater than 50% pain relief with documented functional improvement after a single block before fusion. One additional society (Latin American Society of Regional Anesthesia) abstained on the statement that the evidence is stronger for extra-articular than intra-articular injections. The committee found that a battery of physical exam tests has reasonable sensitivity, but lower specificity, for identifying intra-articular but not extra-articular pathology, with negative tests having greater predictive value than positive ones. Intra-articular injections have diagnostic validity for SIJ intra-articular, but not extra-articular pain. There is unclear or negative evidence for imaging. The prevalence rates of intra-articular and extra-articular pathology are comparable, with both intra- and extra-articular steroid injections providing at least 4 weeks of relief in well-selected patients. However, the evidence is slightly stronger for extra-articular corticosteroid injections to provide short-term relief. The evidence base for non-interventional therapies is indirect, extrapolated mostly from low back pain studies. There is weak evidence supporting dextrose-based prolotherapy and platelet-rich plasma to provide at least 3 months of pain relief. There is strong evidence for sacral lateral branch RFA to provide relief for at least 6 months in individuals with extra-articular pathology, with face validity and indirect evidence from randomized trials supporting sacral lateral branch blocks as a prognostic tool. There is stronger evidence for larger lesions or more aggressive lesioning strategies than for less stringent techniques. There is weak evidence to support non-steroidal anti-inflammatory drugs to prevent neuritis after RFA, and in most cases anticoagulation does not require cessation in the periprocedural perioid. With an aggressive lesioning strategy, sensory stimulation provides minimal therapeutic benefit, with weak, extrapolated evidence that motor stimulation can provide safety benefit. The cutoff to designate diagnostic or prognostic blocks as positive is most commonly set at 50%, with higher values not shown to improve outcomes for more definitive procedures; for therapeutic treatment outcomes, the evidence supports a lower threshold of ≥30% pain relief or meaningful benefit on non-pain outcomes (eg, opioid cessation) for designation of a positive response. For carefully selected patients with intra-articular SIJ complex pain based on controlled blocks who have failed conservative therapies, there is weak or very weak evidence that minimally invasive SIJ fusion can provide benefit for at least one year. Conclusions SIJ complex pain remains an underappreciated source of chronic low back pain, affecting between 15% and 30% of patients with axial pain predominantly below L5. Answers to many questions were limited by low-quality evidence, indicating the need for better research. SIJ complex pain is a multifarious condition (ie, pain can be from different portions of both the intra- and extra-articular components of the joint) for which an interdisciplinary, multimodal treatment plan can optimize treatment outcomes.
Practice advisory for intravenous management of headache disorders in hospitalized patients: a review of the evidence and consensus recommendations
Hoydonckx, Yasmine , Feoktistov, Alexander, Amoozegar, Farnaz , Anderson, C. , Barad, Meredith , Burke, Emeralda , Chitsantikul, Prin, Doshi, Tina L , Englesakis, Marina , Goel, Akash , Gupta, Himanshu , Kirschner, Abby, Kohan, Lynn , Lauritsen, Clinton G. , Miller, Franziska , Monsour, Danny, Nader, Antoun , Ogunlaja, Oyindamola, Silberstein, Stephen D., Souza, Dmitri , Kohan, Lynn R , Nader, Antoun , Schwenk, Eric S , Yuan, Hsiangkuo , Englesakis, Marina , Doshi, Tina L , Barad, Meredith J , Gupta, Himanshu, Kissoon, Narayan , Schuster, Nathaniel M. , Schwenk, Eric S. , Yuan, Hsiangkuo , Narouze, Samer

Regional Anesthesia & Pain Medicine | July 2, 2025 | Volume: 51 | Issue: 2 | Pages: 117-131

10.1136/rapm-2025-106718 Get It

Introduction Patients hospitalized for headache treatment pose unique challenges to the healthcare system. Currently, there is a lack of evidence-based guidance on management. This practice advisory aims to fill this critical gap by systematically reviewing the existing literature and providing comprehensive, evidence-based recommendations for managing headache patients during hospitalization. Methods In February 2023, the American Society of Regional Anesthesia and Pain Medicine approved this practice advisory proposal. The steering committee selected committee members based on clinical and research expertise in the field of headache medicine. Nine questions were formulated by the committee, and each question was assigned to a group composed of 3–4 members. A systematic literature search for each question was performed in Medline, Embase, Cochrane Database of Systematic Reviews and Web of Science on June 21, 2023. The results from each search were imported into separate Covidence projects for screening, data extraction, and risk of bias assessment. Additionally, relevant systematic reviews (SR) were screened. Each group submitted a structured narrative review along with statements and recommendations based on the US Preventive Services Task Force (USPSTF) format for grading of evidence. While the USPSTF framework was used, including the language in the recommendations, the formal USPSTF methodology, including the SR with meta-analysis and summary tables with forest plots, was not followed because of low overall evidence quality. The interim draft was shared electronically with each collaborator, who was requested to vote anonymously using two rounds of the modified Delphi approach. A consensus recommendation required >75% agreement. Results The panel generated 12 statements and 17 recommendations, along with their strength and certainty of evidence. Following two rounds of Delphi voting, a high consensus was achieved for all statements and recommendations. Most statements received a low-to-moderate level of certainty, and all but one recommendation received grade B or C, which was consistent with the lack of randomized controlled trials supporting most of the drugs in this document. Conclusions This evidence-based practice advisory provides a foundational step toward standardizing inpatient headache care and highlights existing gaps in the literature that should be addressed through rigorous prospective randomized studies.
Percutaneous Interventional Strategies for Migraine Prevention: A Systematic Review and Practice Guideline
Barad, Meredith , Schuster, Nathaniel M. , Schuster, Nathaniel M , Barad, Meredith J , Ailani, Jessica , Hakim, Sameh Michel , Kissoon, Narayan

Pain Medicine | August 2, 2021 | Volume: 23 | Issue: 1 | Pages: 164-188

10.1093/pm/pnab236 Get It

AbstractObjectiveTo systematically evaluate the efficacy and effectiveness of percutaneous interventional treatments for prevention of migraine through a qualitative and (when possible) quantitative analysis.MethodsAn expert panel was asked to develop recommendations for the multidisciplinary preventive treatment of migraine, including interventional strategies. The committee conducted a systematic review and (when evidence was sufficient) a meta-analytic review by using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) criteria and the modified Cochrane Risk of Bias analysis available in the Covidence data management program. Clinical questions addressed adults with migraine who should be offered prevention. Examined outcomes included headache days, acute medication use, and functional impairment. Acute management of migraine was outside the scope of this guideline.ResultsThe committee screened 1,195 studies and assessed 352 by full text, yielding 16 randomized controlled trials that met the inclusion criteria.Recommendations and ConclusionsAs informed by evidence related to the preselected outcomes, adverse event profile, cost, and values and preferences of patients, onabotulinumtoxinA received a strong recommendation for its use for chronic migraine prevention and a weak recommendation against its use for episodic migraine prevention. Greater occipital nerve blocks received a weak recommendation for their use for chronic migraine prevention. For greater occipital nerve block, steroid received a weak recommendation against its use vs the use of local anesthetic alone. Occipital nerve with supraorbital nerve blocks, sphenopalatine ganglion blocks, cervical spine percutaneous interventions, and implantable stimulation all received weak recommendations for their use for chronic migraine prevention. The committee found insufficient evidence to assess trigger point injections in migraine prevention and highly discouraged the use of intrathecal medication.
Quality Improvement in Neurology: Headache Quality Measurement Set
Robbins, Matthew S. , Victorio, M. Cristina, Bailey, Mark, Cook, Calli , Garza, Ivan , Huff, J. Stephen, Ready, Duren Michael, Seidenwurm, David , Seng, Elizabeth K. , Szperka, Christina L. , Lee, Erin , Villanueva, Raissa, Seng, Elizabeth , Robbins, Matthew S , Szperka, Christina L , Schuster, Nathaniel M.

Headache: The Journal of Head and Face Pain | September 23, 2020 | Volume: 61 | Issue: 1 | Pages: 219-226

10.1111/head.13988 Get It