Genicular Nerve Radiofrequency Ablation for Chronic Knee Pain After Total Knee Arthroplasty

More than 600,000 total knee arthroplasty (TKA) surgeries are performed each year in the United States, and approximately 20% of patients will experience some element of chronic knee pain or dissatisfaction related to pain following this procedure. The options for management are limited, and physicians often resort to chronic opioid management. This creates a less than ideal situation for our elderly population who are more sensitive to the deleterious effects of opioids and who would greatly benefit from pain-free, independent mobility. The investigators propose a single-arm pilot study looking at performing fluoroscopically guided genicular nerve radiofrequency ablation (RFA) for patients with chronic (>6 months) knee pain following a TKA.

A new paradigm for treating post-TKA pain may be the use of RFA of the articular sensory nerve supply of the knee capsule, to desensitize the knee by blocking sensory afferents of the anterior capsule and thereby decreasing pain. While this modality has demonstrated efficacy for chronic knee pain due to osteoarthritis (OA) in the native knee, only one underpowered study has investigated this technique in chronic pain post-TKA. Further, this study targeted only three genicular nerves, while newer cadaveric studies have suggested multiple additional sensory nerves which if ablated may result in increased pain relief. A placebo-controlled explanatory trial of genicular nerve RFA for chronic pain post-TKA of appropriate size and statistical methodology has not been conducted.

Inclusion criteria

• Age 30 to 90 years
• At least one year post TKA
• Have no indications for revision TKA
• ≥4/10 knee pain for >6 months following TKA
• ≥80% relief with diagnostic genicular nerve blocks
• Willingness to undergo fluoroscopy-guided genicular nerve RFA treatment.

Exclusion criteria

• Conditions that preclude RFA (e.g. pregnancy, pacemaker/ICD, severe cardiac/pulmonary compromise; acute illness/infection; coagulopathy or bleeding disorder; allergic reactions/contraindications to a local anesthetic.
• Inability to write, speak or read in English
• Patient refusal
• Significant psychiatric comorbidity