Abstract
OBJECTIVES: Diagnostic medial branch blocks (MBB) are considered the reference standard for diagnosing facetogenic pain and selecting patients for radiofrequency (RF) denervation. Great controversy exists regarding the ideal cutoff for designating a block as positive. The purpose of this study is to determine the optimal pain relief threshold for selecting patients for RF denervation after diagnostic MBB. METHODS: In this multicenter, prospective correlational study, 61 consecutive patients undergoing lumbar facet RF denervation after experiencing significant pain relief after MBB were enrolled. A positive outcome was defined as a ≥50% reduction in back pain at rest or with activity coupled with a positive satisfaction score lasting longer than 3 months. The relationship between pain relief after the blocks and denervation outcomes was evaluated by pairwise correlation matrix, receiver's operating characteristic curve, and stratifying outcomes based on 10- and 17-percentage point intervals for MBB. RESULTS: There were no significant differences in RF outcomes based on any MBB pain relief cutoff over 50%. A trend was noted whereby those patients who obtained <50% pain relief reported poorer outcomes. No optimal threshold for designating a diagnostic block as positive, above 50% pain relief, could be calculated. CONCLUSION: Employing more stringent selection criteria for lumbar facet RF is likely to result in withholding a beneficial procedure from a substantial number of patients, without improving success rates.
Original language | English (US) |
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Pages (from-to) | 382-391 |
Number of pages | 10 |
Journal | Clinical Journal of Pain |
Volume | 29 |
Issue number | 5 |
DOIs | |
State | Published - May 1 2013 |
Keywords
- facet joint
- low back pain
- predictive value
- radiofrequency
- specificity
- zygapophysial
ASJC Scopus subject areas
- Clinical Neurology
- Anesthesiology and Pain Medicine