BackgroundModic change grading is heterogeneous, inconsistent, and lacks a single nomenclature across the published literature. A new method of Modic change classification has been established by Dr. Peter Udby which hopes to unify how Modic changes are classified while also adding grading of the cranial/caudal extent of the Modic change across the vertebral body from the respective endplate involved to best capture the clinically relevant information of Modic changes.MethodsTwenty magnetic resonance images of potential basivertebral nerve ablation candidates were independently reviewed by two board-certified and fellowship trained neuroradiologist and two board-certified and fellowship-trained interventional spine physiatrists for the presence and characterization of Modic changes using the newly described Udby classification. 100% agreement of all four reviewers of Modic change presence, Type, and Udby classification was required to be classified as agreement. There were 480 total data points each with 10 unique choices to compare across the four independent reviewers.ResultsThe kappa value of their agreement was 0.5899 (95% CI 0.4860–0.6939).ConclusionThis study, requiring unanimous agreement between 4 physicians in application of the Udby classification, demonstrated an interrater reliability score of 0.5899 (95% CI 0.4860–0.6939). While this figure provides a first estimate, larger scale research is necessary before definitive claims regarding the interrater agreement validity of the Udby characterization system may be made.

Background Emerging literature supports the use of basivertebral nerve ablation (BVNA) for a specific cohort of patients with chronic low back pain and Type 1 or Type 2 Modic changes from vertebral levels L3-S1. The early literature warrants further evaluation. Studies establishing the efficacy of BVNA use highly selective patient criteria. Objective. Provide a first estimate of the prevalence of BVNA candidates in a spine clinic over a year using the foundational studies patient selection criteria? Methods A retrospective review of four fellowhsip trained spine physiatrists patient encounters at a large academic medical center using relevant ICD-10 codes to isolate chronic low back pain without radiating symptoms from January 1, 2019 to January 1, 2020. Charts were then reviewed by a team of physicians for exclusionary criteria from the foundational studies which have demonstrated benefit from BVNA. MRI's from qualifying charts which did not meet exclusionary criteria were then independently reviewed by four physician for localization and characterization of Modic changes. Results The relevant diagnostic codes query yielded 338 unique patient records. Based on exclusionary criteria or lack of imaging availability, 318 charts were eliminated. The remaining 20 charts qualified for imaging review. There were 11 charts in which there was 100% agreement between all reviewers regarding the presence and either Type 1 or Type 2 Modic changes between vertebral levels L3 to S1. Accordingly, the prevalence of eligibility for BVNA was 3% (11/338, 95% CI 1-5%). Conclusion The population which may benefit from BVNA is small. Our study demonstrated that over a year, the prevalence for BVNA candidacy using the foundational studies criteria was 3% (95% CI 1% - 5%). While physicians may be tempted to use less stringent selection criteria in practice, upon doing so they cannot cite the foundational studies as evidence for the outcomes they expect to achieve. Those outcomes will require more studies which formally assess the benefits of BVNA when selection criteria are relaxed.

BACKGROUND CONTEXT The zygapophysial joint (facet joint) is the primary etiology in an estimated 5-45% of chronic low back pain (CLBP) cases. Medial branch radiofrequency neurotomy (RFN) is a validated and effective intervention to treat this. A medial branch block (MBB) is the currently the standard for diagnosis of zygapophysial joint pain and can be used to select patients for RFN. However, the ideal MBB diagnostic paradigm is unclear, given that the false positive rate for a single MBB is estimated at 15-45%. Some practitioners argue for a single MBB, others argue for dual MBB, and others support a no-block protocol. Among those supporting MBB as a diagnostic and prognostic tool, there is ongoing debate around the level of pain relief required to declare an MBB successful; commonly used values range from 50% pain reduction to 100%. PURPOSE To determine the extent to which clinical practice using dual MBBs and a ≥80% pain relief cut off approximates the statistical foundational studies upon which guidelines from NASS and Medicare LCD were based. STUDY DESIGN/SETTING Retrospective review study at a single academic institution PATIENT SAMPLE Patients who received their first lumbar medial branch block in a 12-month period from Jan 1, 2019 through Dec 31, 2019. OUTCOME MEASURES The percentage of patients who progressed from first to second MBB, and ultimately RFN. METHODS The cohort charts were individually reviewed by a team of physicians using a predetermined set of inclusion and exclusion criteria. Inclusion criteria: First lumbar medial branch block was performed between January 1st, 2019 to December 31st, 2019. Exclusion criteria: The patient had previously undergone MBB or RFN at the specified level. If the patient did not follow up after the first or second medial branch block, they were considered a failure to progress. RESULTS A total of 174 patients underwent initial MBB. 124 (71%) patients had a positive first block and progressed to a second MBB. Of these, 105 (85% of those receiving MBB #2) progressed to RFN. Using a dual MBB paradigm, 60% (105/174) of patients undergoing initial lumbar MBB proceeded to RFN. CONCLUSIONS Increasing the specificity of patient selection for RFN increases the odds of the procedure being successful. This must be balanced against the risk of withholding potentially therapeutic treatment to patients who might benefit from intervention. Nonetheless, there is ongoing debate as to whether the dual MBB protocols used in research translates to the clinical setting. This cohort demonstrates that using a single MBB "screens out" nearly 30% of patients initially considered for RFN, and a second MBB "screens out" an additional 15%. In this study, dual MBBs and a ≥80% pain relief cutoff reduced the pool of RFN candidates by 40%. While the first block screens out the majority of patients that do not have zygapophyseal joint pain, a second MBB does result in added specificity. This cohort shows that a dual block paradigm in clinical practice is feasible and confers clinical utility in selecting patients for RFN. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs. The zygapophysial joint (facet joint) is the primary etiology in an estimated 5-45% of chronic low back pain (CLBP) cases. Medial branch radiofrequency neurotomy (RFN) is a validated and effective intervention to treat this. A medial branch block (MBB) is the currently the standard for diagnosis of zygapophysial joint pain and can be used to select patients for RFN. However, the ideal MBB diagnostic paradigm is unclear, given that the false positive rate for a single MBB is estimated at 15-45%. Some practitioners argue for a single MBB, others argue for dual MBB, and others support a no-block protocol. Among those supporting MBB as a diagnostic and prognostic tool, there is ongoing debate around the level of pain relief required to declare an MBB successful; commonly used values range from 50% pain reduction to 100%. To determine the extent to which clinical practice using dual MBBs and a ≥80% pain relief cut off approximates the statistical foundational studies upon which guidelines from NASS and Medicare LCD were based. Retrospective review study at a single academic institution Patients who received their first lumbar medial branch block in a 12-month period from Jan 1, 2019 through Dec 31, 2019. The percentage of patients who progressed from first to second MBB, and ultimately RFN. The cohort charts were individually reviewed by a team of physicians using a predetermined set of inclusion and exclusion criteria. Inclusion criteria: First lumbar medial branch block was performed between January 1st, 2019 to December 31st, 2019. Exclusion criteria: The patient had previously undergone MBB or RFN at the specified level. If the patient did not follow up after the first or second medial branch block, they were considered a failure to progress. A total of 174 patients underwent initial MBB. 124 (71%) patients had a positive first block and progressed to a second MBB. Of these, 105 (85% of those receiving MBB #2) progressed to RFN. Using a dual MBB paradigm, 60% (105/174) of patients undergoing initial lumbar MBB proceeded to RFN. Increasing the specificity of patient selection for RFN increases the odds of the procedure being successful. This must be balanced against the risk of withholding potentially therapeutic treatment to patients who might benefit from intervention. Nonetheless, there is ongoing debate as to whether the dual MBB protocols used in research translates to the clinical setting. This cohort demonstrates that using a single MBB "screens out" nearly 30% of patients initially considered for RFN, and a second MBB "screens out" an additional 15%. In this study, dual MBBs and a ≥80% pain relief cutoff reduced the pool of RFN candidates by 40%. While the first block screens out the majority of patients that do not have zygapophyseal joint pain, a second MBB does result in added specificity. This cohort shows that a dual block paradigm in clinical practice is feasible and confers clinical utility in selecting patients for RFN.

BACKGROUND:Chronic axial neck pain (CANP) due to zygapophysial joint arthropathy is best diagnosed via cervical medial branch block (MBB). However, the paradigm by which MBB is used to select patients for cervical radiofrequency neurotomy (RFN) is contested. Dual diagnostic cervical MBB with a minimum of ≥80% pain relief to diagnose cervical zygapophysial joint pain has been accepted by some Medicare Local Coverage Determinations as the method for selecting patients for cervical RFN. There are some who would argue that the utility of the dual diagnostic MBB and the ≥80% pain relief cut off lacks utility in clinical practice. The suspicion being those who progress from MBB1 to MBB2 will then flow from MBB2 to RFN without fail. Does clinical practice using dual diagnostic MBBs and using an ≥80% pain relief cut off reduce patient eligibility for cervical RFN after both MBB1 and MBB2?METHODS:A retrospective clinical audit was carried out at an academic institution spine center from January 1st to December 31st, 2019. Charts were selected based on Current Procedural Terminology codes for MBB, then included if the cervical medial branches were targeted. Charts were then reviewed for procedural progression.RESULTS:21/51 (24%, 95% Confidence Interval 12-35%) patients progressed from MBB1 to MBB2. Of those 21 patients, 13 patients progressed from MBB2 to RFN (62%, 95% CI 41-83%). In total, 13/51 (14%, 95% CI 14-37%) patients who were initially suspected to have CANP due to zygapophysial joint pain progressed to RFN. Both MBB1 and MBB2 hindered the progression of 30/51 patients (59%, 95% CI 45-72%) and 8/21 patients (38%, 95% CI 17-59%), respectively.CONCLUSION:Both MBB1 and MBB2 served to filter patients from progression to RFN using dual MBBs with an ≥80% pain relief cutoff.