The effectiveness and safety of sacral lateral branch radiofrequency neurotomy (SLBRFN): A systematic review.

Objective: To assess the effectiveness and safety of sacral lateral branch radiofrequency neurotomy (SLBRFN) in treating posterior sacroiliac joint complex (PSIJC) pain, stratifying results by patient selection criteria and technique. Design: Systematic review. Population: Adults over 18 years old with suspected PSIJC pain. Intervention: SLBRFN with image guidance (including computed tomography, fluoroscopy, ultrasound). Comparison: Any other treatment, sham, or no treatment. Outcomes: The primary outcome was improvement in pain reported as continuous data or the proportion of patients obtaining ≥50% reduction in pain scores on either the visual analog scale (VAS) or numeric rating scale (NRS). Secondary outcomes included functional improvement, reported as continuous data or the proportion of patients obtaining ≥30% in function from baseline, and adverse events. Methods: Six reviewers independently assessed publications prior to December 2022 in PubMed, EMBASE, Web of Science, and Google Scholar and utilized the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) framework to evaluate the overall quality of evidence. Results: Of the 415 publications screened, 37 met the inclusion criteria, with 33 providing sufficient data regarding the effectiveness of SLBRFN. Of the included studies, there were four explanatory randomized controlled trials (RCTs), four pragmatic RCTs, 11 prospective cohort studies, 14 retrospective cohort studies, and four case reports describing adverse events. At 6 months, the proportion of patients with ≥50% pain relief ranged from 19 to 89%. Studies providing continuous data reported that patients achieved 40-60% pain relief sustained at 12 months. There was heterogeneity in reporting functional improvement, but most studies noted improvement. While all studies that reported categorical outcomes targeted the S1-3 sacral lateral branches, the majority also included RFN of the L5 dorsal ramus. Successful outcomes were reported in patients selected by the response to intra-articular blocks (single or dual) or sacral lateral branch blocks (single or dual). Twenty-nine total adverse events and three serious adverse events (SAE) were reported across 1367 patients. According to the GRADE system, there is moderate-quality evidence overall that SLBRFN effectively reduces pain and disability in a majority of patients with PSIJC pain at 1, 3, 6, and 12 months. When anatomically validated SLBRFN techniques are assessed, the level of evidence is upgraded to high quality. Discussion/conclusion: Despite the variability in types of radiofrequency technology, technique, nerve targets, and study methodology, most studies found that substantial proportions of patients achieved ≥50% relief at 1, 3, 6, and 12 months following SLBRFN. When anatomically validated SLBRFN techniques are applied, there is a high level of confidence that the procedure effectively reduces pain and improves function in patients with PSIJC pain. Additional high-quality studies exploring the prognostic value of different block protocols and the relative effectiveness of the various SLBRFN procedure techniques are needed to further optimize the clinical outcomes of SLBRFN.