Two-Needle Technique for Lumbar Radiofrequency Medial Branch Denervation: A Technical Note

Background: Radiofrequency ablation (RFA) of the medial branches of the dorsal rami has been reported to relieve facet joint–related back pain for 6 months to 1 year in 60% of patients. Although providing benefit in a significant proportion of patients, there remains a group of patients who do not experience any pain relief from RFA or experience only benefit from the ablation for a short period. Failure of RFA has been attributed to technical failure of coagulating the nerve or coagulation of a minimal section of the nerve, allowing for early reinnervation. Increasing the success rate and duration of relief may require techniques that increase the likelihood of successful nerve ablation over a relevant distance by maximizing lesion size. Objectives: The aim of this technical note is to detail a modification to the current commonly used lumbar medial branch radiofrequency (RF) denervation approach to increase lesion size. Study Design: This is a technical report describing a novel two-needle approach to lumbar RF medial branch denervation. Setting: Large private interventional pain management institute. Methods: A dual needle placement of two 10-mm active tip RF cannulas separated by 6 mm is used to optimally contact the superior articular process (SAP) from its ventral to dorsal borders, which encompasses the anticipated course of the medial branch nerves. Results: The described technique creates a lesion that we estimate to be 11.0-mm wide and 11.6-mm long along the course of the medial branch adjacent to the SAP ensuring adequate coverage and treatment. Limitations: This report does not encompass a systematic evaluation of the clinical safety and efficacy of the two-needle RFA approach. Future studies will have to assess the longterm efficacy and safety of the approach. Conclusions: The detailed two-needle approach to lumbar RF medial branch denervation appears to be promising in terms of projected treatment success by coagulating a large volume of tissue, in a cost- and time-efficient manner. Key words: Radiofrequency ablation, RFA, lumbar, medial branch, facet joint, pain, rhizotomy