The Analgesic Effectiveness of Genicular Nerve-targeted Cooled and Pulsed Radiofrequency Ablation for Osteoarthritis Knee Pain: A Systematic Review and Meta-analysis.

Background: Radiofrequency ablation (RFA) is a form of therapy for knee osteoarthritis (OA) pain that has become more popular in recent years. In addition to standard RF approaches, there are cooled and pulsed options. RFA could be used to treat the superolateral, superomedial, and inferomedial branches of the genicular nerves. Pulsed and cooled RF ablation on the genicular nerve to treat knee OA pain, however, has not yet been shown to be effective.

Objectives: We conducted a meta-analysis to assess nonconventional, pulsed or cooled, RFA on the genicular nerve to treat knee OA pain; intended our study to provide useful information in deciding whether to use nonconventional RFA because of its effectiveness.

Study Design: Meta-analysis study of nonconventional, pulsed or cooled, RFA on the genicular nerve to treat knee OA pain.

Methods: PubMed, Ovid MEDLINE, Scopus, and Cochrane Central were searched for eligible papers. In our literature review, procedures, posttreatment outcomes, follow-up data, and adverse events were compiled and analyzed from the selected studies. The National Heart, Lung, and Blood Institute Quality Assessment tool was used to assess therapeutic relevance and evidence strength. Our meta-analysis analyzed pre- and posttreatment pain and physical function scores. The primary outcome was pain measured with either the Visual Analog Scale  or the Numeric Rating Scale. The secondary outcome was physical function measured with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score.

Results: Our systematic review and meta-analysis includes 11 eligible publications (604 patients). Both cooled and pulsed RFA procedures targeting the genicular nerve resulted in considerable pain reduction at post one, 3, 6, and 12 months (P < 0.005). There was no significant improvement in physical function outcome for the cooled RFA technique in all follow-up visits. There was a significant improvement in physical function outcome for the pulsed RFA technique at the one-month and 3-month follow-up visits.

Limitations: Limitations include that there are a limited number of randomized controlled trials available, the methodology utilized for comparison is based on the change in outcome between baseline and follow-up visits. There are only a few papers that have reported physical function outcomes in complete WOMAC rating data.

Conclusion: At the 6-month follow-up, both cooled and pulsed RFA targeting the genicular nerve provided significant osteoarthritic pain alleviation. There is no different in pain relief between cooled and pulsed RFA targeting the genicular nerve for treating knee osteoarthritis. There was no significant functional improvement of cooled RFA in all follow-ups, but there was a significant functional improvement of pulsed RFA up to 3-month follow-up. According to our study, knee osteoarthritis pain can be efficiently treated with pulsed and cooled radiofrequency with few adverse effects.