Knee Radiofrequency Ablation for Osteoarthritis Pain

What is genicular nerve radiofrequency ablation?

The knee receives its pain sensation through several small nerve branches that surround it, called the genicular nerves. Radiofrequency ablation is a technique that applies controlled heat, through a very fine needle, to those nerve branches. Doing so interrupts, for a period of time, the transmission of pain from the joint to the brain.

There is something important to understand from the start: this procedure treats the pain, not the arthritis. The cartilage wear is still there; what changes is how much it hurts. So it is not a cure, and it does not repair the joint. It is a tool to help you hurt less and move better, as part of a broader plan that we support with physical therapy.

What kind of pain is it indicated for?

Knee radiofrequency ablation is intended for people with knee osteoarthritis pain that keeps bothering them despite well-conducted conservative treatment: pain relievers, anti-inflammatories when they can be used, physical therapy and, in some cases, prior injections.

• Pain lasting more than 3 to 6 months from osteoarthritis confirmed on X-ray or MRI.
• Pain that limits walking, climbing stairs or sleeping, and that has not improved enough with the above.
• People who, because of their age, overall health or personal preference, are looking for a pain-relief option while they evaluate or wait on the rest of their treatment plan.
• A knee replacement that still hurts: in carefully evaluated cases, radiofrequency ablation can also help with that pain.

When surgery is indicated, radiofrequency ablation does not replace it or compete with it: it can be an option for managing pain along the way, and the surgical decision is always one you discuss with your orthopedic surgeon.

The step before: the diagnostic block

Before radiofrequency ablation, in most cases we perform a test block: those same nerves are temporarily numbed with a small amount of local anesthetic. If that block clearly reduces your pain for a few hours, it is a good sign that radiofrequency ablation is more likely to work. It is a simple filter that helps us avoid proposing a procedure that is unlikely to help you.

What is the day of the procedure like?

It is an outpatient procedure: you come in and walk out the same day. No hospital stay is required.

• It is performed with local anesthesia at the needle entry points. Sedation is generally not needed, although light sedation can be offered to people who feel very anxious.
• I guide it with imaging (fluoroscopy or ultrasound) to locate each genicular nerve precisely. That guidance is key to making it safe and effective.
• Once the needles are in the right place, radiofrequency heat is applied for a few minutes at each point.
• The whole procedure usually takes 30 to 45 minutes.
• Afterwards you stay in observation for a while and, unless instructed otherwise, you go home the same day. It is a good idea to have someone accompany you.

What results should you expect?

I will be honest with you about the timeline and what the evidence shows. In studies, a good proportion of well-selected patients achieve a significant reduction in pain that typically lasts around 6 months, with variability from person to person; in some, relief lasts longer, and when the pain returns, the procedure can be repeated. Not everyone responds the same way, which is why the prior test block is so useful.

• Relief is not always immediate: it can appear gradually over the first 1 to 4 weeks.
• The effect is temporary because, over time, the nerves can start transmitting pain again. When that happens, the procedure can be repeated.
• It mainly improves pain and, in many cases, function for walking and daily activities. It does not correct the deformity or the cartilage wear.
• In experienced hands and with image guidance, it is a procedure with a good safety profile according to the available evidence; serious complications are uncommon.

I would rather be clear than overpromise. Knee radiofrequency ablation will not give you your cartilage back or take away the arthritis; what it aims to do is make your knee hurt considerably less for several months, so you can sleep, walk and do your physical therapy with a different outlook. That is why I insist so much on the test block: if your pain does not improve when those nerves are numbed, I would rather not offer you radiofrequency ablation and think through something else with you.

I also want you to know that this is decided case by case. I look at the knee, the imaging, which treatments you have already tried and what you hope to achieve. Sometimes radiofrequency ablation is clearly the right choice; other times it makes more sense to first get the baseline treatment in order, or to discuss the situation with your orthopedic surgeon. The idea is that the option we choose makes sense for you — not to apply the same thing to everyone.

Where is it performed? Locations in Buenos Aires

I see patients at two locations: Hepta, in San Isidro (Av. Fondo de la Legua 577, northern Buenos Aires suburbs) and CIAREC, in Villa Urquiza (Av. Monroe 4770, Buenos Aires City). In the consultation we assess your case and coordinate where and when to perform the procedure. I receive patients from across the northern suburbs of Greater Buenos Aires and from Buenos Aires City. Phone: (011) 5895-3260.

Insurance coverage

Genicular nerve radiofrequency ablation is covered by most Argentine private health plans and obras sociales (Argentine health funds), usually with prior authorization. In the consultation we assess your case and, if the procedure is indicated, we prepare the documentation your health plan needs to authorize it. It can also be done on a self-pay basis. Fees and arrangements are discussed in the consultation, depending on the location and your situation.

When to seek a consultation and next steps

It makes sense to seek a consultation if your knee osteoarthritis pain has been going on for several months, limits your daily life, and has not improved enough with pain relievers, physical therapy or injections. In the consultation we review your imaging, talk about what you have already tried, and decide whether radiofrequency ablation is a reasonable option for you or whether another path makes more sense.

I see patients in San Isidro (Hepta) and Villa Urquiza (CIAREC), and I also offer virtual consultations for a first evaluation or to review imaging remotely.

Dr. Mauricio Casarsa

Anesthesiologist. Postgraduate training in Pain Medicine and Interventional Pain Management (UBA — Fundación Dolor; UNLP — CAIDBA). Staff physician at Hospital Alemán de Buenos Aires.

MN 137.756 (Argentine medical license) · San Isidro · Villa Urquiza