SUMMARY OF BACKGROUND DATA: Lumbar medial branch radiofrequency ablation (LMBRFA) is an effective treatment for facet joint pain. LMBRFA efficacy was originally demonstrated using a parallel technique. Newly developed RFA probes (, Trident) allow a perpendicular approach (P-LMBRFA), which may simplify the RFA technique and lead to superior treatment success rates. However, further investigation is necessary to determine whether these technologies are associated with improved patient outcomes. OBJECTIVES: Evaluate the effectiveness of P-LMBRFA in patients with confirmed facet pain. METHODS: In this retrospective single-arm cohort study, electronic medical records were used to identify consecutive patients with ≥80 % dual medial branch block-confirmed pain relief who underwent first-time P-LMBRFA between 2016 and 2022. Primary outcomes were ≥50 % Numerical Rating Scale (NRS) pain improvement and the minimal clinically important difference (MCID) on the Pain Disability Quality-of-Life Questionnaire (PDQQ) at 3 months post-treatment. Secondary outcomes included the duration and mean retrospective percentage of pain relief after a successful index P-LMBRFA in individuals who reported a return of their index symptoms. RESULTS: 174 participants (60.3 % female, 61.3 ± 14.2 years of age, BMI 29.5 ± 6.7 kg/m) were analyzed. Success rates for ≥50 % NRS reduction and MCID on the PDQQ at 3 months were 50.6 % (95 % CI = 43.3-57.9 %) and 50.0 % (95 % CI = 42.8-57.2 %), respectively. Of the 88 successful P-LMBRFAs, 60 patients experienced a return of symptoms after 8.7 ± 3.6 months and reported a retrospective mean percentage pain relief of 81.8 % ± 15.8 %. DISCUSSION/CONCLUSION: Following P-LMBRFA, approximately 50 % of patients reported improvement in pain and disability measures. Extensive, prospective research comparing long-term outcomes of P-LMBRFA and parallel LMRBFA is warranted.