What is the optimal block selection paradigm for predicting a successful treatment outcome following sacral lateral branch radiofrequency neurotomy? A real-world cohort study

Katharine A Smolinski; Christopher Radlicz; Hasan Sen; Amanda N Cooper; Brook Martin; Alycia Amatto; Allison Glinka Przybysz; Robert Burnham; Aaron M Conger; Zachary L McCormick; Taylor R Burnham

doi:10.1016/j.inpm.2025.100599

What is the optimal block selection paradigm for predicting a successful treatment outcome following sacral lateral branch radiofrequency neurotomy? A real-world cohort study

Interv Pain Med. 2025 Jun 2;4(2):100599. doi: 10.1016/j.inpm.2025.100599. eCollection 2025 Jun.

Authors

Affiliations

¹ Department of Physical Medicine and Rehabilitation, University of Utah, Salt Lake City, UT, USA.
² Division of Physical Medicine and Rehabilitation, Washington University in Saint Louis, Saint Louis, MO, USA.
³ Department of Orthopedics, University of Utah Salt Lake City, UT, USA.
⁴ Division of Physical Medicine and Rehabilitation, Department of Medicine, University of Alberta, Edmonton, AB, Canada.
⁵ Central Alberta Pain and Rehabilitation Institute, Lacombe, AB, Canada.
⁶ Vivo Cura Health, Calgary, AB, Canada.

Abstract

Background: Outcomes following sacral lateral branch radiofrequency neurotomy (SLBRFN) likely depend on patient selection criteria; however, commonly used criteria vary considerably. Refinement of selection criteria for SLBRFN may improve treatment outcomes. This study investigated common prognostic block-based selection criteria and treatment success following SLBRFN.

Methods: In this retrospective cohort study, consecutive patients from two Canadian musculoskeletal pain management clinics who underwent SLBRFN over a 6-year period (2016-2022) were identified by electronic medical record. Patients were categorized according to several prognostic block paradigms based on number of blocks (single vs. dual), block type (lateral branch block [LBB] vs. intra-articular block [IAB]), and subsequent percentage of pain relief. Six block criteria were established: 1 = LBB/LBB≥80 %; 2 = IAB/LBB≥80 %; 3 = LBB/LBB 50-79 %; 4 = IAB/LBB 50-79 %; 5 = LBB≥80 %; 6 = LBB 50-79 %. Treatment success was assessed at three months post-SLBRFN using two criteria: (1) the primary study outcome of ≥50 % numerical rating scale (NRS) pain reduction and (2) a secondary outcome of Pain Disability Quality-of-Life Questionnaire (PDQQ) score improvement by the minimal clinically important difference (MCID). Logistic regression analyses evaluated the association between block criteria and treatment success following SLBRFN.

Results: 281 consecutive patients (75.1 % female, 61.8 ± 14.2 years of age, BMI 29.4 ± 6.6 kg/m²) were included. Cohort success rates for pain and functional improvement were 43.4 % (95 % CI: 37.8-49.3) and 46.6 % (95 % CI: 40.9-52.5), respectively. After adjusting for demographics and cannula type/SLBRFN technique, none of the odds ratios for the six prognostic block paradigms showed statistical significance.

Conclusion: Nearly 50 % of patients who underwent SLBRFN reported clinically significant improvement in pain and disability at three months post-procedure, regardless of prognostic block selection criteria. These results suggest that multiple block strategies may determine eligibility for SLBRFN.

Keywords: Radiofrequency ablation; Radiofrequency neurotomy; Sacral lateral branch; Sacroiliac joint pain.