Radiofrequency Ablation for Knee Pain: How It Works and Who It Helps

Key Takeaways

Radiofrequency ablation (RFA) uses heat to temporarily disable nerves that transmit knee pain signals
The procedure typically provides 6-12 months of relief for chronic knee osteoarthritis pain
Best suited for patients who haven’t responded well to conservative treatments but want to avoid surgery
Medicare and most insurance plans cover RFA when medical necessity is documented

If you’ve been living with chronic knee pain that hasn’t improved with other treatments, you may have heard about radiofrequency ablation. This minimally invasive procedure offers a different approach than injections or medications—it targets the nerves that send pain signals from your knee to your brain.

Let’s explore how RFA works, who benefits most, and what you can realistically expect from this treatment option.

What Is Radiofrequency Ablation?

Radiofrequency ablation (RFA) is a medical procedure that uses heat energy to temporarily disable specific nerves around your knee joint. These nerves, called genicular nerves, transmit pain signals from your knee to your brain.

Think of it like turning down the volume on a radio. RFA doesn’t fix the underlying arthritis or damage in your knee, but it interrupts the pain messages traveling through those nerves. When the nerves can’t send signals effectively, you feel less pain.

The procedure is also called:

RFA (radiofrequency ablation)
Radiofrequency neurotomy
Nerve ablation
RF lesioning

Unlike medications that affect your whole body or injections that work inside the joint, RFA targets only the specific nerves responsible for knee pain.

How Does the Procedure Work?

RFA is typically performed as an outpatient procedure in a doctor’s office or surgical center. Here’s what happens:

Before the Procedure

Your doctor will likely perform diagnostic nerve blocks first. These test injections use numbing medication to temporarily block the genicular nerves. If these blocks significantly reduce your pain (usually by 50% or more), you’re considered a good candidate for RFA.

This diagnostic step is important because it confirms which nerves are contributing to your pain. Insurance companies typically require successful nerve blocks before approving RFA.

During the Procedure

The actual RFA procedure takes about 30-45 minutes:

Preparation: You’ll lie on a procedure table, and the skin around your knee will be cleaned and numbed with local anesthetic.
Needle placement: Your doctor uses X-ray guidance (fluoroscopy) to insert thin needles near the genicular nerves around your knee. You may feel pressure but shouldn’t feel sharp pain.
Testing: A small electrical current is sent through each needle to make sure it’s positioned correctly. You might feel tingling or muscle twitching—this is normal and helps confirm proper placement.
Numbing: Once the needles are in position, more numbing medication is injected around each nerve.
Heating: The radiofrequency energy is activated, heating the tip of each needle to about 176°F (80°C). This heat creates a small lesion on the nerve that disrupts its ability to transmit pain signals. Each site is heated for 60-90 seconds.
Completion: The needles are removed, and small bandages are applied.

After the Procedure

You’ll rest for a short time and can usually go home the same day. Most people need someone to drive them home.

What to Expect: Recovery and Results

Recovery from RFA is generally straightforward, but it’s important to have realistic expectations.

Immediate Recovery (Days 1-3)

Soreness at the needle insertion sites is common
Your knee may feel temporarily worse due to inflammation from the procedure
Ice packs and over-the-counter pain relievers can help
Most people return to normal activities within a day or two

Pain Relief Timeline (Weeks 1-4)

This is where RFA differs from injections:

Relief isn’t immediate—it typically takes 2-4 weeks to feel the full benefit
As the treated nerves gradually stop functioning, pain decreases
Some people notice improvement within a week, while others need the full month
Don’t judge the success of the procedure in the first few days

Expected Duration

When RFA works, pain relief typically lasts:

Average duration: 6-12 months
Range: Some people get 3-6 months, others get 12-24 months
Repeat treatments: RFA can be repeated when pain returns because nerves eventually regenerate

Research shows that about 60-70% of patients experience significant pain reduction (50% or more) after RFA. This is good, but not perfect—it means the procedure doesn’t work for everyone.

Who Is a Good Candidate for RFA?

RFA isn’t a first-line treatment for knee pain. It’s best suited for specific situations:

Ideal Candidates

Adults with chronic knee osteoarthritis causing persistent pain for at least 6 months
Pain primarily from the bones and ligaments around the joint (not inside the joint)
Failed to get adequate relief from conservative treatments like physical therapy, medications, or injections
Want to avoid or delay knee replacement surgery
Had successful diagnostic nerve blocks (50% or more pain reduction)
Overall good health to undergo a minor procedure

Who May Not Be a Good Candidate

RFA may not be appropriate if you have:

Acute knee pain (recent injury)
Pain primarily from inside the joint (where genicular nerves don’t reach)
Active infection in or around the knee
Severe bleeding disorders
Unstable joint that needs surgical repair
Pain well-controlled by other treatments

Your doctor will evaluate your specific situation, including imaging studies (X-rays or MRI) and your response to diagnostic nerve blocks.

Comparing RFA to Other Knee Pain Treatments

How does RFA stack up against other non-surgical options?

RFA vs. Hyaluronic Acid Injections

Hyaluronic acid (gel shots) work by cushioning and lubricating inside the knee joint:

Relief typically lasts 3-6 months
Injections go into the joint space
Best for mild to moderate osteoarthritis
Usually less expensive than RFA

RFA targets nerves outside the joint:

Relief typically lasts 6-12 months
Better for bone-on-bone pain
More invasive procedure
May cost more initially

Many patients try gel shots first because they’re less invasive. If those don’t provide enough relief, RFA becomes an option.

RFA vs. Cortisone Injections

Cortisone shots reduce inflammation:

Faster relief (within days)
Shorter duration (4-12 weeks)
Limited number of injections per year
Work inside the joint

RFA interrupts pain signals:

Slower onset (2-4 weeks)
Longer duration (6-12 months)
Can be repeated as needed
Works on nerves outside the joint

Some patients use cortisone for acute flare-ups and RFA for longer-term pain management.

RFA vs. Surgery

Knee replacement permanently replaces damaged joint surfaces:

Major surgery with significant recovery time
Permanent solution for severe arthritis
Higher risks and complications
Not reversible

RFA is temporary and reversible:

Minimally invasive with quick recovery
Doesn’t alter joint structure
Can be repeated
Buys time before surgery

RFA is often called a “bridge therapy”—it can help you stay active and delay surgery, sometimes for years.

Insurance Coverage and Costs

The good news: Medicare and most private insurance plans cover radiofrequency ablation for knee pain when it’s medically necessary.

What Insurance Typically Requires

Documentation of conservative treatment failure: You’ve tried physical therapy, medications, and possibly injections without adequate relief
Successful diagnostic nerve blocks: You had at least 50% pain reduction from test injections
Clear medical necessity: Your doctor documents that knee pain significantly affects your daily activities and quality of life
Supporting imaging: X-rays or MRI showing osteoarthritis or joint degeneration

Cost Breakdown

If your insurance covers RFA:

Your out-of-pocket costs depend on your deductible and copay/coinsurance
Typical patient responsibility: $200-$1,000

If paying out-of-pocket:

Diagnostic nerve blocks: $500-$1,500 per session (usually 2 blocks needed)
RFA procedure: $3,000-$6,000
Total self-pay cost: $4,000-$9,000

Medicare typically covers RFA under Part B when medical necessity is documented. Your 20% coinsurance would apply after you meet your deductible.

Always verify coverage with your insurance company before scheduling the procedure.

Potential Risks and Limitations

While RFA is generally safe, it’s important to understand the potential downsides.

Common Side Effects

Soreness or bruising at needle sites (very common)
Temporary increase in knee pain (first few days)
Numbness or odd sensations around the knee
Mild swelling

Less Common Complications

Infection (rare, less than 1%)
Nerve damage to nearby nerves
No pain relief (happens in 30-40% of patients)
Bleeding or hematoma
Allergic reaction to numbing medication

Limitations to Understand

Not a cure: RFA manages pain but doesn’t fix the underlying arthritis. Your knee isn’t any healthier after the procedure—it just hurts less.

Temporary relief: Nerves regenerate over time, so pain eventually returns. The procedure can be repeated, but each time may be less effective.

Doesn’t work for everyone: About 30-40% of patients don’t get significant relief even with successful nerve blocks.

Activity limitations remain: Even with less pain, your knee still has arthritis. You shouldn’t push beyond safe activity levels just because it doesn’t hurt as much.

Is RFA Right for You?

Consider radiofrequency ablation if:

You’ve tried other treatments without adequate relief
Your knee pain significantly limits your daily activities
You want to delay or avoid knee replacement surgery
You’re willing to undergo diagnostic nerve blocks first
You understand the relief is temporary and may need to be repeated

Talk to your doctor about whether RFA makes sense for your specific situation. Ask these questions:

Have I tried all the appropriate conservative treatments first?
Am I a good candidate based on my pain pattern and imaging results?
What are the chances this will work for me specifically?
How long can I expect relief if the procedure is successful?
What’s my backup plan if RFA doesn’t provide enough relief?

The Bottom Line

Radiofrequency ablation offers a middle ground between conservative treatments and surgery for chronic knee pain. It won’t fix your arthritis, but it may significantly reduce pain for 6-12 months or longer by interrupting the nerves that transmit pain signals.

The procedure is minimally invasive with a quick recovery, but it takes several weeks to feel the full benefit. Success rates are good but not guaranteed—about 60-70% of carefully selected patients get meaningful relief.

If you’ve exhausted other options and aren’t ready for knee replacement, RFA is worth discussing with your doctor. It may help you stay active, reduce your need for pain medications, and buy valuable time before considering surgery.

Frequently Asked Questions

How painful is the RFA procedure?

The procedure itself causes minimal pain because local anesthetic is used. You’ll feel pressure and possibly some tingling when nerves are tested, but sharp pain should be minimal. The most uncomfortable part is often the soreness for a few days afterward.

How long does radiofrequency ablation last for knee pain?

Most patients experience pain relief for 6-12 months. Some get as little as 3-6 months, while others enjoy relief for 12-24 months. Duration varies based on individual factors and how quickly nerves regenerate.

Can radiofrequency ablation be repeated?

Yes, RFA can be repeated when pain returns. However, some doctors report that repeat procedures may be less effective over time. There’s no specific limit on how many times it can be done.

Does Medicare cover radiofrequency ablation for knees?

Yes, Medicare Part B covers RFA for knee pain when medical necessity is documented. This typically requires failed conservative treatment and successful diagnostic nerve blocks. Your 20% coinsurance applies after meeting your deductible.

What’s the success rate of radiofrequency ablation for knee pain?

Studies show that 60-70% of properly selected patients achieve at least 50% pain reduction. Success rates are higher when patients had excellent response to diagnostic nerve blocks and have arthritis primarily affecting the bones around the joint rather than inside it.

This article is for educational purposes and does not replace medical advice. Always consult with a healthcare provider about treatment options appropriate for your specific condition.

Last medically reviewed: March 2025