Radiofrequency Ablation of the Sensory Innervation
of the Knee(Genicular RFA)
A New Evidence-Based, Minimally Invasive Option for Controlling Refractory Knee Pain
Knee pain can be refractory to conventional treatments. Surgery is not always indicated or readily accessible. This is particularly the case in Alberta. As the population ages and obesity is prevalent, so is knee osteoarthritis.
Orthopedic assessment and surgical wait times have been exacerbated by the pandemic. Unfortunately, even after knee arthroplasty, some patients continue to have knee pain.
Thermal ablation of some of the sensory innervation of the knee (genicular radiofrequency ablation or “GRFA”) is a new minimally invasive method of knee pain control. Conventional radiofrequency ablation (RFA) of the genicular nerves has been shown to provide moderate intermediate term relief. The safety and efficacy of genicular RFA was assessed in 3 separate systematic reviews this year which are summarized below.
Subsequently, research has provided additional refinements to patient selection, sensory nerve targets and thermal lesion type which should make the procedure even more effective.
Conclusion(Verbatim from Abstract)
Chen, A. F., Mullen, K., Casambre, F., Visvabharathy, V., & Brown, G. A. (2021). Thermal Nerve Radiofrequency Ablation for the Nonsurgical Treatment of Knee Osteoarthritis: A Systematic Literature Review. The Journal of the American Academy of Orthopaedic Surgeons, 29(9), 387–396. https://doi.org/10.5435/JAAOS-D-20-00522
Li, G., Zhang, Y., Tian, L., & Pan, J. (2021). Radiofrequency ablation reduces pain for knee osteoarthritis: A meta-analysis of randomized controlled trials. International journal of surgery (London, England), 91, 105951. https://doi.org/10.1016/j.ijsu.2021.105951
Zhang, H., Wang, B., He, J., & Du, Z. (2021). Efficacy and safety of radiofrequency ablation for treatment of knee osteoarthritis: a meta-analysis of randomized controlled trials. The Journal of international medical research, 49(4), 3000605211006647. https://doi.org/10.1177/03000605211006647
These results demonstrate geniculate nerve thermal RFA to be a superior nonsurgical treatment of knee OA compared with NSAIDs and IA corticosteroid injections. None of the RCTs reported any serious AEs with geniculate nerve thermal RFA, as opposed to known cardiovascular, gastrointestinal, and renal AEs for NSAIDs and accelerated cartilage loss and periprosthetic infection risk for IA corticosteroid injections. Level of Evidence: Level I
RFA showed better effectiveness in relieving pain and promoting function recovery in patients with knee OA. Considering the small sample size of the included studies, the results should be treated with caution
Radiofrequency ablation is efficacious and safe for reducing pain and improving knee function in patients with knee osteoarthritis, without increasing the risk of adverse effects.
Genicular RFA is an outpatient procedure involving precise placement of small thermal lesions over sensory branches of the peripheral nerves innervating the joint (see figure below). The procedure is done under local anesthetic, fluoroscopic and/or ultrasound guidance and takes 30-60 minutes to perform per knee.
Patients with refractory knee pain (i.e. patients with moderate to advanced osteoarthritis [Kellgren-Lawrence grade 3-4] who may not be candidates for arthroplasty due to age, comorbidities; patients who are on the arthroplasty waitlist but need better pain relief while they wait; patients with persistent pain following arthroplasty etc.).
We will assess potential candidates and perform image guided prognostic local anesthetic genicular sensory nerve blocks. Patients must experience ≥80% pain relief and improvement in function to be considered a candidate. Patients with pacemakers or neurostimulators are not candidates for GRFA.
Post Procedure Care
Typically, patients have mild increased soreness of the treated joint for few days post procedure. Postprocedure rehabilitation is important. Accordingly, all patients will be strongly encouraged to participate in a post GRF lower extremity functional rehabilitation program including education, strengthening and neuromuscular training (i.e. GLA:D or STEP programs). Outcome measures will be followed and reported.
Accessing the Services
You can refer potential candidates for GRFA by sending a referral letter to our fax# 4037826511
Your patient will undergo an intake assessment which will include local anesthetic sensory blocks of the genicular nerves. If the selection criteria are met, the GRFA procedure will be discussed with the patient, including procedural cost and postprocedure rehabilitation.