Low back pain is the #1 contributor to years lived with disability (CLBP; pain persisting for ≥3 months). An obstacle to reducing the societal burden of CLBP is that most treatments have only small effects (~5-10% improvements in functional limitations and pain) when compared to a control treatment. Lumbar radiofrequency ablation (LRFA) is a minimally invasive procedure that is widely performed for CLBP. It can be used in patients for whom CLBP is isolated to the lumbar facet joints, defined by pain relief (“positive responses”) after local anesthetic medial branch blocks (MBBs) to the medial branch nerves. LRFA applies a thermal lesion to these nerves, temporarily reducing or eliminating CLBP. Unlike most CLBP treatments, LRFA can result in large improvements in properly selected patients. However, LRFA is neurodestructive, has potential adverse effects, and there is conflicting evidence regarding its effectiveness as seen in randomized controlled trials (RCTs). Experts have noted that those RCTs showing no effects of LRFA may be explained by (1) poor LRFA technique insufficient to adequately lesion the medial branches, and (2) suboptimal clinical selection criteria for identifying LRFA candidates. The most stringent evidence-based guidelines for LRFA technique and patient selection are those of the Spine Intervention Society (SIS). The SIS guidelines mandate various aspects of technique to optimize medial branch lesioning and consequent improvements in CLBP. They also include stringent clinical screening criteria for determining appropriate LRFA candidates, such as requiring ≥80% pain improvement to define positive MBB responses, and 2 separate sets of comparative MBBs with low anesthetic volume (<0.5cc). A definitive RCT of LRFA vs. control has yet to be conducted. Despite this, LRFA using conventional electrodes (LRFA-C) and new technological modifications to LRFA are now commonly used. These modifications are intended to make the procedure easier to perform and faster than LRFA-C. Among these modifications, LRFA using multi-tined electrodes (LRFA-M) has shown the greatest promise. However, there are no RCTs examining whether LRFA-M improves clinical outcomes compared to a simulated LRFA control procedure, or whether it is actually easier or faster to perform than LRFA-C. We propose A Superiority Trial of Lumbar Radiofrequency Ablation for Low back pain, or “ASTRAL”: a definitive, double-blind, 3-arm, multicenter trial to examine the effectiveness of LRFA-C and LRFA-M, each compared to a simulated ablation control procedure (simulated LRFA). ASTRAL will use the SIS criteria for LRFA technique and patient selection. Aim 1 is to compare the effectiveness of LRFA-C with simulated LRFA for improving back-related functional limitations. Aim 2 is to compare the effectiveness of LRFA-M with simulated LRFA for improving back-related functional limitations. Secondary aims will compare LRFA-C and LRFA-M with regards to procedure duration, radiation...