Nerve Blocks and RFA: What You Need to Know About Interventional Pain Procedures

When chronic pain won’t go away, pills and physical therapy often aren’t enough. That’s when many patients turn to nerve blocks and radiofrequency ablation (RFA)-two interventional pain procedures that target the source of pain, not just the symptoms. These aren’t surgeries. They’re precise, minimally invasive treatments done in outpatient settings, often with just local anesthesia and mild sedation. But they’re not the same. Understanding the difference can make all the difference in your pain relief journey.

How Nerve Blocks Work (And When They Help)

A nerve block is exactly what it sounds like: a doctor injects medication-usually a local anesthetic like lidocaine, sometimes combined with a steroid-right next to a nerve that’s sending pain signals to your brain. The goal? To temporarily block those signals. Think of it like hitting pause on pain.

It’s fast. The procedure takes about 10 to 20 minutes. You’re awake, maybe a little drowsy from light sedation. You’ll feel a small pinch when the needle goes in, then a warm sensation as the medicine spreads. Within minutes, the area that’s been hurting for months might feel numb or completely pain-free.

But here’s the catch: that relief doesn’t last. Most nerve blocks offer hours to a few weeks of relief. For some people with acute flare-ups-like a sudden pinched nerve or post-surgical pain-that’s enough. For others with chronic conditions like arthritis or spinal facet joint pain, it’s just a temporary fix.

That’s why nerve blocks are often used as a diagnostic tool. If you get 80% or more pain relief after a nerve block, it tells your doctor: Yes, this nerve is the problem. If you don’t feel much difference? Then the pain is coming from somewhere else. That’s critical. You don’t want to go ahead with a more involved procedure like RFA if the nerve block didn’t work.

What Is Radiofrequency Ablation (RFA)?

RFA is where things get more permanent. Instead of temporarily numbing the nerve, RFA uses heat to disable it. A thin needle, guided by real-time X-ray imaging (fluoroscopy), is placed right next to the nerve causing pain. Then, a small electrical current is sent through the needle, heating the tip to between 80°C and 90°C. That heat creates a tiny lesion on the nerve-just big enough to stop it from sending pain signals.

It’s not destroying the nerve permanently. Nerves can regenerate over time, which is why relief typically lasts 6 to 24 months. But for many, that’s a game-changer. You’re not curing arthritis or degenerative disc disease. You’re cutting off the pain signal it produces.

The procedure takes 20 to 45 minutes, depending on how many nerves are treated. You’re awake, but you won’t feel the heat because the area is numbed. Before the heat is applied, your doctor will test the needle’s position by sending small electrical pulses. You’ll feel a tingling or muscle twitch-this confirms the needle is touching the right nerve and not a motor nerve that controls movement.

Afterward, you might feel soreness or aching at the injection site for a few days. That’s normal. Full pain relief usually builds over 2 to 4 weeks as the nerve fully stops sending signals. Most people are back to light activity within 24 hours and back to work in 2 to 3 days.

Why RFA Beats Nerve Blocks for Long-Term Relief

Let’s compare them side by side.

• Nerve blocks: Lasts hours to weeks. Good for diagnosis or short-term flare-ups. Low cost, low risk.
• RFA: Lasts 6 to 24 months. Good for chronic pain that hasn’t responded to other treatments. Higher upfront cost, but fewer repeat procedures needed.

According to data from the Hospital for Special Surgery, RFA works for 70% to 80% of patients with chronic low back pain from facet joints. That’s significantly higher than the 30% to 50% success rate you see with repeated nerve blocks over time.

For knee osteoarthritis, a 2023 study showed that cooled RFA-using a special electrode that creates a larger treatment zone-helped 65% of patients maintain pain relief for six months. Standard cortisone injections? Only 45% saw improvement at three months.

And compared to surgery? RFA is a no-brainer. Spinal fusion requires weeks of recovery, carries a 10% to 15% risk of complications, and costs $20,000 to $50,000. RFA? Around $3,000 to $5,000. Outpatient. No general anesthesia. No hospital stay.

Who Is a Good Candidate for RFA?

Not everyone qualifies. The biggest rule? You must have had a successful diagnostic nerve block first. If you didn’t get at least 80% pain relief from that initial injection, RFA is unlikely to help. That’s not just a suggestion-it’s standard practice backed by the Spine Intervention Society and the American Society of Anesthesiologists.

Good candidates usually have:

• Chronic low back or neck pain from facet joints
• Knee osteoarthritis that hasn’t responded to physical therapy or injections
• Sacroiliac joint pain
• Occipital neuralgia (headaches from irritated nerves at the base of the skull)
• Plantar fasciitis that won’t quit

Age matters too. People between 45 and 65 with degenerative joint changes respond best. Younger patients often have pain from injury or inflammation, which may respond better to other treatments. Older patients may have too many other health issues to be ideal candidates.

And if you’re on opioids? RFA can help you cut back-or even stop. One study from Gardner Orthopedics found 70% of patients reduced or eliminated opioid use after RFA.

What About Pulsed RFA and Newer Technologies?

Traditional RFA uses heat. But there’s a newer version called pulsed radiofrequency (PRF). Instead of heating the nerve to 80°C, PRF sends short bursts of high-voltage energy. It doesn’t destroy the nerve-it just resets how it sends pain signals. Think of it like rebooting a glitchy computer.

PRF is great for people who can’t tolerate heat, like those with sensitive nerves or who’ve had complications before. It’s also being used for conditions like trigeminal neuralgia and chronic headaches. Recovery is faster, and there’s almost no risk of nerve damage. But the relief doesn’t last as long-usually 3 to 6 months.

Then there’s cooled RFA. This uses a special needle that circulates coolant around the tip, allowing a larger area of nerve tissue to be treated without burning surrounding tissue. It’s especially useful for bigger nerves, like those around the knee. Studies show cooled RFA gives longer-lasting relief than traditional RFA for knee pain.

In 2022, the FDA approved the first pulsed-field ablation system for spinal pain. It uses electrical pulses instead of heat to disrupt nerves. Early results show faster recovery and less post-procedure soreness. It’s still new, but it’s the next step forward.

What Are the Risks?

RFA and nerve blocks are both low-risk. But nothing’s risk-free.

The most common side effect? Temporary soreness at the injection site. It usually fades in 3 to 7 days. Some people get a brief flare-up of pain-called neuritis-where the nerve becomes irritated. That lasts about 1 to 2 weeks and responds well to ice and over-the-counter painkillers.

Bigger risks are rare. Infection happens in less than 1% of cases. Nerve damage that causes numbness or weakness is extremely uncommon-especially when done by an experienced provider using real-time imaging. The biggest mistake? Treating the wrong nerve. That’s why the diagnostic block is non-negotiable. Without it, about 20% to 30% of RFA procedures don’t work.

And if you have a pacemaker or other implanted device? Tell your doctor. Some RFA equipment can interfere with those devices.

What Happens After the Procedure?

You’ll go home the same day. No driving for 24 hours. Rest the first day. Light walking is encouraged. Avoid heavy lifting or strenuous activity for 48 hours.

Don’t expect instant relief. Pain relief builds over time. Some people feel better in a week. Others take 3 to 4 weeks. That’s because the nerve needs time to fully stop sending signals after being heated.

Keep a pain diary. Note when the relief starts, how strong it is, and if anything triggers a return of pain. That info helps your doctor decide if and when you might need another RFA.

Most patients return to normal activity within 2 to 3 days. Many say they can finally sleep through the night, walk without a cane, or play with their grandkids again.

Is RFA Right for You?

If you’ve tried physical therapy, NSAIDs, and steroid injections-and you’re still in pain-RFA might be your next step. But only if you’ve had a successful diagnostic nerve block.

It’s not a cure. You still have arthritis. You still have degenerated discs. But you don’t have to live with the pain they cause.

It’s also not a last resort. The American Society of Anesthesiologists now recommends RFA as a standard second-line treatment after conservative therapies fail-before you even consider surgery.

And with the global RFA market growing at 14.3% per year, it’s clear: more people are choosing it. More doctors are offering it. More insurance plans are covering it.

If you’re tired of pain controlling your life, ask your pain specialist: Have I had a proper diagnostic nerve block? Am I a candidate for RFA? That simple question could change everything.