Citations

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.

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.

Abstract Objective The aim of this study was to evaluate the efficacy and safety of a 60‐day peripheral nerve stimulation (PNS) treatment targeting the occipital nerves for reducing pain and improving function in individuals diagnosed with cervicogenic headache or occipital neuralgia. Background Headache conditions are prevalent and commonly disabling, and conventional therapeutic strategies are often insufficient. Development of a percutaneous 60‐day PNS treatment has created new opportunities to evaluate PNS of the occipital nerves. Methods This study was an institutional review board‐approved, multicenter, prospective, single‐arm study that enrolled participants from October 2022 to March 2024. Participants with cervicogenic headache or occipital neuralgia received a 60‐day PNS treatment targeting the occipital nerves. The primary endpoint was the proportion reporting clinically significant (≥30%) reductions in average pain and/or pain interference at end of treatment (EOT). Additional analysis included the proportion of participants with ≥50% reduction in average pain intensity and/or pain interference and additional outcomes including Patient Global Impression of Change, six‐item Headache Impact Test, and Neck Disability Index. Results At EOT, 90% of participants (18/20) met the primary endpoint. Further, 85% (17/20) and 83% (15/18) reported ≥50% reductions in pain and/or pain interference at EOT and 3 months, respectively. Clinically meaningful improvements were observed in functional and headache‐related disability and quality‐of‐life measures. All study‐related adverse events were non‐serious. Conclusion Most participants reported significant reductions in pain and/or pain interference following 60‐day PNS targeting the occipital nerves. Outcomes through 3 months demonstrate how 60‐day PNS offers an effective approach for the treatment of headache.

We describe a case of spontaneous intracranial hypotension secondary to a CSF-venous fistula that was treated with transvenous embolization. We present the imaging findings from a brain MRI before and after embolization demonstrating changes in the patient’s mamillopontine distance. Decreased mamillopontine distance is a marker of spontaneous intracranial hypotension and a minor criterion in the Bern Score.

CSF-venous fistulas (CVFs) are a common cause of spontaneous intracranial hypotension. These fistulas usually occur without any preceding major trauma, surgery, or other iatrogenic cause. Occasionally, patients have a history of minor trauma, though such cases are usually still considered spontaneous. Little is known about predisposing factors that cause patients to develop spontaneous CVFs. Most patients with CVFs have multiple meningeal diverticula on spine imaging, and fistulas usually arise in association with a diverticulum. In the vast majority of cases, the culprit diverticulum from which the CVF arises is atraumatic in origin, presumably on the spectrum of normal variation in spinal anatomy. Here, we present two cases of CVFs that arose in association with posttraumatic pseudomeningoceles. To our knowledge, this phenomenon has not yet been reported, and it potentially represents a novel etiology for CVFs that furthers understanding of their pathogenesis.

Abstract Objective To develop machine learning models using patient and migraine features that can predict treatment responses to commonly used migraine preventive medications. Background Currently, there is no accurate way to predict response to migraine preventive medications, and the standard trial‐and‐error approach is inefficient. Methods In this cohort study, we analyzed data from the Mayo Clinic Headache database prospectively collected from 2001 to December 2023. Adult patients with migraine completed questionnaires during their initial headache consultation to record detailed clinical features and then at each follow‐up to track preventive medication changes and monthly headache days. We included patients treated with at least one of the following migraine preventive medications: topiramate, beta‐blockers (propranolol, metoprolol, atenolol, nadolol, timolol), tricyclic antidepressants (amitriptyline, nortriptyline), verapamil, gabapentin, onabotulinumtoxinA, and calcitonin gene‐related peptide (CGRP) monoclonal antibodies (mAbs) (erenumab, fremanezumab, galcanezumab, eptinezumab). We pre‐trained a deep neural network, “TabNet,” using 145 variables, then employed TabNet‐embedded data to construct prediction models for each medication to predict binary outcomes (responder vs. non‐responder). A treatment responder was defined as having at least a 30% reduction in monthly headache days from baseline. All model performances were evaluated, and metrics were reported in the held‐out test set (train 85%, test 15%). SHapley Additive exPlanations (SHAP) were conducted to determine variable importance. Results Our final analysis included 4260 patients. The responder rate for each medication ranged from 28.7% to 34.9%, and the mean time to treatment outcome for each medication ranged from 151.3 to 209.5 days. The CGRP mAb prediction model achieved a high area under the receiver operating characteristics curve (AUC) of 0.825 (95% confidence interval [CI] 0.726, 0.920) and an accuracy of 0.80 (95% CI 0.70, 0.88). The AUCs of prediction models for beta‐blockers, tricyclic antidepressants, topiramate, verapamil, gabapentin, and onabotulinumtoxinA were: 0.664 (95% CI 0.579, 0.745), 0.611 (95% CI 0.562, 0.682), 0.605 (95% CI 0.520, 0.688), 0.673 (95% CI 0.569, 0.724), 0.628 (0.533, 0.661), and 0.581 (95% CI 0.550, 0.632), respectively. Baseline monthly headache days, age, body mass index (BMI), duration of migraine attacks, responses to previous medication trials, cranial autonomic symptoms, family history of headache, and migraine attack triggers were among the most important variables across all models. A variable could have different contributions; for example, lower BMI predicts responsiveness to CGRP mAbs and beta‐blockers, while higher BMI predicts responsiveness to onabotulinumtoxinA, topiramate, and gabapentin. Conclusion We developed an accurate prediction model for CGRP mAbs treatment response, leveraging detailed migraine features gathered from a headache questionnaire before starting treatment. Employing the same methods, the model performances for other medications were less impressive, though similar to the machine learning models reported in the literature for other diseases. This may be due to CGRP mAbs being migraine‐specific. Incorporating medical comorbidities, genomic, and imaging factors might enhance the model performance. We demonstrated that migraine characteristics are important in predicting treatment responses and identified the most crucial predictors for each of the seven types of preventive medications. Our results suggest that precision migraine treatment is feasible.