Stratus radiofrequency ablation (RFA) represents an innovative, minimally invasive technique for the treatment of spinal pain, particularly chronic lower back pain and cervicalgia. By using a multi-tined electrode, this technology allows for larger and more homogeneous lesions, improving the capture of target nerves and resulting in long-lasting clinical outcomes.
This article explores how Nimbus Stratus is applied to spinal pain, its mechanisms of action, and the evidence supporting its efficacy.
Treating Vertebral Pain: Lower Back and Neck Pain
Spinal pain, including low back pain and neck pain, is a leading cause of disability worldwide. In many cases, the source involves facet joints, sacroiliac joints, or posterior nerve structures that continue to generate pain despite conservative treatment.
Nimbus Stratus is specifically indicated for:
- Chronic sacroiliac joint pain, confirmed through diagnostic blocks.
- Cervical pain related to third occipital nerve (TON) and cervical medial branch involvement.
- Selected cases of facet-mediated lumbar pain where nerve ablation can reduce pain signaling.
The minimally invasive nature of the procedure makes it suitable even for patients who have failed conservative management or who are not candidates for surgery.
How Radiofrequency Targets Spinal Nerve Pain
The mechanism of action of Stratus RFA is based on interruption or modulation of pain signal transmission along specific sensory nerves:
- The device delivers controlled radiofrequency energy that heats the targeted nerve tissue, creating a thermocoagulation lesion (in continuous mode) or a neuromodulatory effect (in pulsed mode).
- By targeting the posterior sacral network (PSN) or cervical medial branches, the device reduces the ability of these nerves to transmit pain signals to the central nervous system.
- The lesion created by Stratus is broader and more uniform, covering the entire target zone more effectively than conventional monopolar RF.
This precision translates into better outcomes and a lower risk of incomplete denervation.
Accurate Localization of Nerve Structures
Successful RFA depends on precise localization of the target nerves. Nimbus Stratus uses:
- Fluoroscopic guidance as the gold standard for electrode positioning.
- Sensory and motor stimulation to confirm nerve proximity while avoiding motor root injury.
- Multi-tined electrodes that expand to cover a wider area, reducing the risk of missing target fibers.
For cervical procedures, careful identification of the TON and adjacent medial branches ensures selective ablation without affecting non-targeted nerves.
Evidence on Pain Relief Duration and Clinical Success
Clinical studies confirm the efficacy and durability of Nimbus Stratus in treating spinal pain:
- Sacroiliac Joint Pain (COBRA-SIJ Trial): Patients experienced >50% pain reduction sustained for 12–24 months, with significant improvements in disability (ODI) and quality of life (EQ-5D).
- Cervical Pain (TON/C3–C4 RFA): Prospective studies show long-term pain relief with minimal adverse events.
- Observational Real-World Data: Reinforces trial findings, with consistent outcomes across diverse clinical settings.
The extended duration of relief allows many patients to reduce or eliminate long-term use of pain medications.
Single vs. Multilevel Treatment Approaches
Nimbus Stratus can be applied in single-level or multilevel interventions:
- Single-level RFA is typically performed when diagnostic blocks confirm a specific pain generator (e.g., unilateral SIJ or a single cervical branch).
- Multilevel RFA is considered in patients with multifactorial pain involving multiple segments. The device’s design allows efficient lesioning across wider areas with fewer passes, optimizing procedural time while maintaining safety.
The choice between these approaches depends on diagnostic findings and patient-specific factors.
Post-Procedure Rehabilitation Strategies
Radiofrequency ablation with Nimbus Stratus is complemented by structured rehabilitation to maximize outcomes:
- Early mobilization is encouraged, as patients typically resume normal activities within 24–48 hours.
- Physical therapy may be recommended to strengthen supporting musculature and prevent recurrence.
- Pain management follow-up ensures that residual or recurrent symptoms are addressed promptly.
Combining RFA with targeted rehabilitation enhances functional recovery and prolongs the benefits of the intervention.
References
- Aaron Conger, DO et al.
“Conventional or Bipolar Radiofrequency Ablation for the Treatment of Sacroiliac Joint Pain? The COBRA-SIJ Study, a Double-Blind, Randomized, Comparative Trial.”
University of Utah, Department of Physical Medicine and Rehabilitation, Protocol Version 3.0, January 3, 2023. - Eldon Y. Loh, MD; Anne M. Agur, PhD; Robert S. Burnham, MD.
“Ultrasound-Guided Radiofrequency Ablation for SI Joint Pain: An Observational Study.”
Spine Intervention Society, Elsevier (Pre-proof), 2022. - IRB Approval Document – Stratus Medical Protocol.
“Prospective Cohort Study of Cervical Radiofrequency Ablation for Axial Neck Pain with Nimbus RFA (TON/C3 & C4 Medial Branch).”
WCG IRB Approval, Sponsor Protocol Number Stratus_001, 2021. - Stratus Medical, Regulatory Division.
“Nimbus Electrosurgical Radiofrequency Multitined Expandable Electrode – Indications for Use and FDA 510(k) Clearance.”
US FDA Device Evaluation, Class II Neurology Device, K-121773, 2012.
