Extended Relief at All Spinal Regions and Lower Lumbar VAS: Endoscopic Rhizotomy vs. Radiofrequency Ablation: A Retrospective Cohort Study

Abstract

Background: Facet joint syndrome accounts for many patients' chronic neck and low back pain. Current interventional treatment options for these conditions include radiofrequency ablation (RFA) and endoscopic rhizotomy (ER), which target the medial branch of the dorsal ramus innervating the facet joint capsule. RFA is a percutaneous procedure in which radiofrequency waves ablate the medial branch. ER, a newer and more invasive procedure, is typically reserved for patients who have not responded to RFA. This retrospective cohort study aims to compare the postoperative pain level (VAS score), duration of pain relief, and opioid intake among patients who have received ER to those of patients who have received RFA. The results of these operations at all 3 spinal levels will be examined.

Objectives: To evaluate the longevity and quality of pain relief status post RFA versus ER for facet joint syndrome.

Study design: A retrospective cohort study that includes patients treated with sequentially with RFA and then ER. The study analyzed the endpoint after each procedure for each spinal region.

Setting: Three urban neuro-spine centers.

Methods: The study utilized the Strengthening the Reporting of Observational Studies in Epidemiology Analysis (STROBE) initiative. Patients with positive diagnostic medial branch blocks (80% pain relief) obtained RFA and ER, in sequence. The region of procedure (cervical, thoracic, or lumbar), morphine milligram equivalent (MME) requirements, VAS pain scores before and after the procedure, and duration of relief were collected from the electronic medical records. Patient follow-ups were conducted at 3 months, 6 months, 9 months, 12 months, and after 12 months.

Results: Among the 234 patients who underwent 511 RFAs and 386 ERs, ER was associated with significantly better efficacy than RFA in VAS scores (P = 0.001), opioid consumption (P = 0.0442), and duration of pain relief (P < 0.0001), with all spinal levels analyzed aggregately. However, with each spinal region analyzed separately, ER was associated with significantly lower VAS scores only in the lumbar spine (P < 0.0001) while the longer duration of relief persisted across all regions (P < 0.05).

Limitations: The study design was retrospective and nonrandomized. The study also did not utilize functional scales, e.g., the Oswestry Disability Index. Finally, ER is not available to the public.

Conclusion: Both procedures decrease pain levels and opioid consumption significantly. ER is associated with lower pain levels, lower opioid consumption, and a longer duration of pain relief than RFA in the aggregate data. However, when each spinal region is re-analyzed separately, ER results in significantly lower pain levels only in the lumbar spine. Nonetheless, ER continues to provide a longer relief duration than does RFA in all spinal regions. Deploying ER sooner in patients with facet joint pain may be more beneficial than performing RFA and waiting for pain symptoms to recur.

Keywords: Pain relief; Radiofrequency Ablation (RFA); Visual analog score (VAS); duration of relief; facet joint syndrome; medial branch nerve ablation; morphine milligram equivalents (MME); opioid intake; Endoscopic rhizotomy (ER).