A Review of Long-Term Pain Relief after Genicular Nerve Radiofrequency Ablation in Chronic Knee Osteoarthritis

Abstract

Background: Studies of radiofrequency ablation (RFA) of genicular nerves have reportedly significantly decreased pain up to 3 months post ablation, but no longer term effects have been reported. We performed an analysis of long-term pain relief of 31 RFA procedures of the genicular nerves to analyze the degree of pain relief past 3 months, culminating at 6 months. Objective: To evaluate the long term efficacy of genicular nerve ablation for management of chronic knee pain due to osteoarthritis. Study Design: Chart review and study design was approved by Newark Health Sciences IRB. Chart review and follow-up was performed on all patients who underwent genicular nerve RFA during the period of February 2014 through August of 2015. During this inclusion period 41 genicular nerve RFAs were performed on 31 patients, 5 patients received RFA procedure in both knees. Patient follow-up was performed via telephone interview or in-office visit at least 3 months and 6 months post RFA. Settings: Procedures were performed in Medical Special Procedures at University Hospital in Newark, NJ, and the Pain Management Center at Overlook Medical Arts Center in Summit, NJ. Methods: Chart review and study design was approved by Newark Health Sciences Institutional Review Board. Chart review was performed from February 2014 and continued through August 2015. Patient follow-up was conducted at 3 and at least 6 months post treatment to gauge degree of pain relief (0 – none, 100% – complete), their current day’s pain score, other treatment modalities tried before RFA, and the medications used. Patients were asked to quantify their satisfaction with procedure length, pre-procedure anxiety, complications, and if they would recommend this procedure to others. Primary and secondary goals were the duration of pain relief after RFA, the quality of pain relief, and the efficacy of our approach for RFA of genicular nerves versus prior published techniques. Results: At 3 month follow-up, the average pain relief was 67% improvement from baseline knee pain, 0% being no relief and 100% being complete relief, and average 0 – 10 pain score was 2.9. At 6 month follow-up, of those who described pain relief at 3 months, 95% still described pain relief. This group’s average percent pain relief was 64% and average day’s 0 – 10 pain score 3.3. Limitations: Our study included a retrospective component in chart review followed by prospective follow-up, only 76% of patients were able to participate in the interview process. Furthermore, some patients suffered from other chronic pain ailments, most commonly chronic back pain, which at times disturbed the patient’s ability to focus on solely knee pain. Conclusions: Based on patient interviews and data collection, RFA of genicular nerves can supply on average greater than 60% pain relief in our patient population for as long as 6 months. Key words: Osteoarthritis, knee osteoarthritis, chronic knee pain, radiofrequency ablation, nerve ablation, genicular nerves, long-term pain relief