Genicular nerve radiofrequency ablation for chronic knee pain

Overview

The genicular nerves are small nerves that carry pain signals from the knee. Genicular nerve radiofrequency ablation, or RFA, uses gentle heat from radio waves to calm these nerves so they send fewer pain signals. It may help some people with chronic knee pain from osteoarthritis, or ongoing pain after knee surgery, including knee replacement. First, a test called a genicular nerve block checks whether these nerves are carrying your pain. RFA does not repair the knee, and results vary.

GSMC is led by Dr. Dharam Mann, who completed fellowships in pain management, cardiac anesthesia and critical care at Massachusetts General Hospital/Harvard.

Watch: how radiofrequency ablation works

Video: “Boston Scientific: How Radiofrequency Ablation (RFA) Works” from Chronic Pain Relief by Boston Scientific on YouTube. It loads from youtube-nocookie.com only when you press play. Shown for general education; GSMC did not produce it. Watch on YouTube

What it is

RFA, also called radiofrequency neurotomy, places thin needles next to the genicular nerves around the knee. A small electrode heats the nerve tissue to interrupt pain signals. Some systems use "cooled" radiofrequency, which can treat a slightly larger area.

RFA targets only the small sensory nerves. It does not affect the muscles that move your knee. Nerves can grow back over time, so pain may return, and the procedure can often be repeated if it helped.

Who it's for

Genicular nerve RFA may help people who have:

• Chronic knee pain from osteoarthritis that has not improved enough with therapy, medicines or injections
• Ongoing knee pain after knee replacement or other knee surgery
• People who are not ready for, or are not good candidates for, knee replacement
• Clear short-term relief from a test genicular nerve block

What the procedure involves, step by step

Step 1: The test block. 1. The skin is numbed. Using X-ray or ultrasound guidance, your physician places a thin needle near each of the genicular nerves (usually three or more) and injects a small amount of numbing medicine. 2. Over the next several hours, you do activities that usually hurt and track your pain in a diary. 3. If your pain clearly improves while the numbing medicine works, RFA may help.

Step 2: Radiofrequency ablation. 1. On a separate day, you lie on a table and the skin is numbed. Light sedation may be offered. 2. Using X-ray guidance, thin RF needles are placed next to each target nerve. 3. Before heating, a test may be done to make sure the needles are in a safe spot. 4. The nerves are treated with gentle heat. This usually takes about 30 to 60 minutes in total. 5. You rest briefly and go home the same day with a driver.

Recovery and what to expect

• Soreness, bruising or a burning feeling around the knee can last one to two weeks.
• Some people have a patch of numb skin near the knee for a while.
• Relief, if it happens, often builds over a few weeks. It may last months, and sometimes longer.
• Staying active and keeping up with exercise may help you get the most from treatment.

Candidacy: who may or may not be a good fit

May be a good fit: people with chronic knee pain from osteoarthritis or after knee surgery who had clear relief from a test genicular nerve block.

May not be a good fit: people with an infection in or near the knee, a loose or failing knee implant, a bleeding problem or blood thinners that cannot be safely paused, certain implanted electrical devices (which may need special planning), or pregnancy. Pain after knee replacement should be checked for infection or implant problems first. People who did not get relief from the test block are less likely to benefit.

Risks in brief

Risks include soreness, bruising, bleeding, infection, temporary numbness or burning of the skin around the knee, and, rarely, nerve injury or skin burn. Pain may not improve, and it can come back as the nerves regrow. We will review your specific risks.

Alternatives

Other options may include physical therapy, weight management, bracing, medicines, steroid or hyaluronic acid (gel) injections, PRP (usually self-pay), peripheral nerve stimulation or a referral to discuss knee replacement.

Frequently asked questions

Insurance

GSMC participates with all Aetna plans, including Aetna HMO, and with many other insurance plans. Coverage for a specific procedure depends on your plan and may need prior authorization; call 732-202-3000 to verify. Our team can help check your benefits before treatment.

See accepted insurance

Related pages

Related conditions

• Knee arthritis
• Knee pain

Related treatments and resources

• Radiofrequency ablation
• Ultrasound-guided nerve injection
• PNS for knee pain
• PRP for knee osteoarthritis
• Genicular artery embolization (GAE)