Genicular radiofrequency ablation.

What it is

Heat applied to sensory nerve branches

Anaesthetic

Local, with sedation; day case

Guidance

X-ray or ultrasound

Duration of relief

Typically 6 to 12 months

Treats the arthritis

No; it treats the pain signal

Performed by

Pain specialists and interventional radiologists

It is sometimes called a genicular nerve block or radiofrequency neurotomy. It does not treat the arthritis itself, change the structure of the joint, or slow its progression. Instead, it reduces the pain the knee produces, which can make activity and exercise more tolerable for a period of months.

RFA is not a first-line treatment. It is generally considered when knee arthritis is causing persistent pain that has not responded to exercise therapy, weight management, simple analgesia, and activity modification, and where surgery is either not wanted, not yet indicated, or not advisable.

What radiofrequency ablation is

Radiofrequency ablation (RFA) is a minimally invasive procedure that uses a controlled pulse of heat to temporarily interrupt the sensory nerves that carry pain signals from the knee to the brain. The nerves targeted are the genicular nerves, which supply the capsule and lining of the knee joint.

It is sometimes referred to as a genicular nerve block, genicular neurotomy, or radiofrequency neurotomy. The procedure does not involve surgery on the knee joint itself. There are no incisions into the knee, no implants, and no change to the bones or cartilage.

RFA does not treat the arthritis. It reduces the pain the arthritic knee produces, for a limited time, so that activity, exercise and daily life become more manageable. The underlying condition continues as it would have otherwise.

Because it works on the nerves rather than the joint, RFA is best understood as a pain-management option rather than a disease-modifying treatment. It sits alongside, not in place of, the measures that actually support joint health over time.

Who it may suit

RFA is not a first-line treatment for knee arthritis. It is generally considered when pain has persisted despite a reasonable trial of conservative management, and where surgery is not the next step.

It may be an option for people who:

• Have knee osteoarthritis causing persistent pain that limits daily activity
• Have tried exercise therapy, weight management, simple analgesia and activity modification without enough relief
• Are not yet ready for, or do not wish to have, joint replacement surgery
• Have medical conditions that make surgery higher risk at present
• Experienced meaningful, if temporary, pain relief from a diagnostic genicular nerve block

It is less likely to help when pain is driven primarily by an inflammatory arthritis flare, a large meniscal tear, or another problem the nerve procedure would not address. It is also not a substitute for surgery when the joint is severely damaged and symptoms justify an operation.

What happens during RFA

This procedure is performed as a day case and usually takes less than an hour.

• You lie on the treatment table, and the skin over the knee is cleaned and numbed with local anaesthetic.
• Using ultrasound or X-ray guidance, a thin needle is placed near each of the target genicular nerves.
• A small probe at the needle tip delivers a brief, controlled pulse of radiofrequency energy, which gently heats the nerve to interrupt its pain signals.
• Several nerves are usually treated in the same session, as pain from the knee often travels along more than one.
• Light sedation may be offered, but the procedure can also be performed with local anaesthetic alone.

Because the work is done outside the joint, there is no surgery on the knee itself and no change to the bones, cartilage, or ligaments.

After the procedure

Most people are up and walking shortly afterwards and go home the same day. It is sensible to arrange someone to drive you, particularly if sedation was used.

Some soreness, bruising, or a transient increase in discomfort at the treatment sites is common for a few days. The full benefit is usually not immediate, as the nerves take time to quieten, and relief typically develops over the first one to two weeks.

How long relief lasts

The effect is temporary because the treated nerves gradually regenerate. Most people who respond experience several months of reduced pain, often in the range of six to twelve months, before sensation returns and symptoms gradually build back.

Responses vary. Some people enjoy a longer benefit; others find relief is shorter or incomplete. A small proportion get little benefit at all. If the initial response was worthwhile, the procedure can be repeated when the pain returns.

The exact duration and pattern of relief vary between individuals and should be discussed with the treating pain specialist. Specific timeframes for Professor Rodda's patients will be confirmed as the service pathway is finalised.

Risks and limitations

RFA is generally well tolerated, but it is not without risk or limitation. Common and important considerations include:

• Temporary soreness, bruising, or numbness around the treatment sites
• A transient increase in knee pain for a few days after the procedure
• Incomplete or no relief, which is why the diagnostic block is performed first
• Gradual return of pain as the nerves regenerate, requiring repeat treatment
• A small risk of infection, bleeding, or injury to nearby structures, as with any needle-based procedure

Importantly, RFA does not slow or halt the arthritis. It does not replace the need for ongoing exercise, weight management, and activity modification, and it does not prevent or delay the eventual need for surgery if the joint deteriorates to the point where an operation is warranted.

Where it fits in your care

Knee arthritis is managed in stages. Exercise therapy, weight management where relevant, activity modification, and appropriate simple analgesia come first and remain the foundation for almost everyone. Injections, including corticosteroid and other intra-articular options, have a limited but real role during flares.

RFA sits in the space between these conservative measures and surgery. It is a tool for reducing pain for a period of months in people who have not responded adequately to first-line care and for whom joint replacement is not the next step, whether for timing, preference, or fitness for surgery.

Questions to ask

• Am I a candidate for RFA, or would an injection or surgery suit me better?

• How much pain relief can I realistically expect, and for how long?

• Will I still need to keep doing my exercises and weight management afterwards?

• Can the procedure be repeated if the pain returns?

• Who will actually perform the procedure, and where will it be done?

Common questions

Is radiofrequency ablation a cure for knee arthritis?

No. RFA does not treat the arthritis itself or alter the structure of the joint. It works by quietening the sensory nerves that carry pain signals from the knee, so it reduces pain rather than changing the underlying condition. The arthritis will continue to progress as it would have otherwise, and the nerves usually recover function over time, which is why the effect is temporary.

How long does the pain relief last?

Relief varies between individuals. Most people who respond experience several months of reduced pain, often in the range of six to twelve months, before the nerves regenerate and symptoms gradually return. Some have a shorter benefit and a small number get little relief at all. The procedure can be repeated if the response was worthwhile.

How do I know if I will respond before having the full procedure?

A diagnostic genicular nerve block is usually performed first. Local anaesthetic is injected around the candidate nerves, and if this produces a meaningful, temporary reduction in pain, it suggests those nerves are carrying the pain signals and that RFA may help. A poor response to the block generally means RFA is unlikely to be beneficial.

Is the procedure painful?

It is performed with local anaesthetic, often with light sedation, so discomfort during the procedure is usually modest. Some soreness or bruising at the treatment sites is common for a few days afterwards. Most people are able to walk out and resume light activity the same day.

Will RFA affect my ability to have knee replacement later?

No. RFA does not alter the joint or the surrounding structures in a way that would prevent or complicate a future knee replacement. It is often used specifically to bridge people who are not yet ready, willing, or medically fit for surgery.

What is the difference between RFA and a cortisone injection?

A corticosteroid injection delivers anti-inflammatory medication into the joint to settle inflammation and swelling. RFA works outside the joint, by interrupting the sensory nerves that transmit pain signals. They act by different mechanisms and are chosen for different reasons, so they are not interchangeable, though both can have a place in managing knee arthritis.

Can I have RFA more than once?

Yes. If the initial procedure provided worthwhile relief and the pain has returned as the nerves regenerated, the treatment can be repeated. Repeat procedures tend to be most useful when paired with ongoing exercise therapy and weight management rather than relied upon in isolation.

Who actually performs the procedure?

Genicular radiofrequency ablation is typically performed by a specialist pain medicine physician or radiologist with expertise in interventional pain techniques, often in a day-procedure or radiology setting. Professor Rodda will advise whether it is appropriate in your case and refer you to the right practitioner if it is.

Frequently asked questions.

References.

1. Choi WJ, Hwang SJ, Song JG, et al. Radiofrequency treatment relieves chronic knee osteoarthritis pain: a double-blind randomized controlled trial. Pain. 2011;152(3):481-487.
2. Hunter C, Davis T, Loudermilk E, et al. Cooled radiofrequency ablation treatment of the genicular nerves in the treatment of osteoarthritic knee pain: 18- and 24-month results. Pain Pract. 2020;20(3):238-246.

This page provides general information about a medical condition and a surgical procedure. It is not individual medical advice and does not replace consultation with a qualified practitioner. Outcomes vary between individuals and all surgery carries risk. A referral is needed for a consultation with Professor Daevyd Rodda; without one, you can start with the practice nurse practitioner, who can provide it.