An ablation of the back is a minimally invasive procedure that uses heat to disable the tiny nerves responsible for sending pain signals from your spinal joints to your brain. The full name is radiofrequency ablation (RFA), sometimes called radiofrequency neurotomy. It’s one of the most common treatments for chronic back pain that originates in the facet joints, the small connecting joints that run along the back of your spine. The procedure doesn’t fix the underlying joint problem, but it interrupts the pain signal, often providing months of relief.
How It Works
Your facet joints are lined with small nerves called medial branch nerves. These nerves have one job: carrying pain signals from the joint to your brain. During an ablation, a doctor inserts a thin, hollow needle through the skin and positions it right next to one of these nerves. An electrode threaded through the needle then delivers radio waves, generating heat at the needle tip. That heat creates a small lesion on the nerve, essentially burning a section of it so it can no longer transmit pain.
In a standard procedure, the needle tip reaches about 80°C (176°F) and is held in place for 90 seconds at each target site. Your doctor uses a real-time X-ray machine called a fluoroscope to guide the needle to exactly the right spot. Multiple nerves are typically treated in a single session, depending on how many spinal levels are involved.
What the Procedure Feels Like
You’ll lie face down on an X-ray table in a hospital gown. Before the radiofrequency needles go in, your doctor injects a numbing agent into the skin at each treatment site. Most people feel pressure and occasional warmth during the procedure, but the local anesthetic keeps sharp pain to a minimum. The entire process usually takes 30 to 90 minutes depending on how many nerves are being treated. You’re awake throughout, though mild sedation is sometimes offered.
Recovery and When Relief Kicks In
Most people return to work and light activities within 24 hours. If your job involves heavy lifting or physical labor, you may need a few extra days. For the first week, avoid bending, twisting, or lifting heavy objects.
Mild redness, swelling, and bruising at the needle sites are normal. Some people notice temporary numbness or tingling. Here’s the part that catches people off guard: your pain may actually return or even feel worse in the days right after the procedure. The treated nerves take time to fully shut down. Most people notice significant improvement within two to three weeks, though it can take longer.
How Well It Works
Roughly half of patients who undergo lumbar radiofrequency ablation achieve at least 50% pain relief within the first 6 to 12 months. A large real-world study found that 51.7% of patients hit that threshold at the 6 to 12 month mark, with the number dropping to about 38% between 12 and 18 months. Those numbers reflect a carefully selected group of patients who first passed diagnostic nerve block tests confirming that their pain was actually coming from the facet joints.
The results aren’t permanent because the treated nerves eventually regrow. This regeneration process is gradual, and the timeline varies. Some people get relief for six months, while others go several years before needing a repeat procedure. In one comparative study, the longest documented relief lasted nearly five years. When pain does return, the procedure can be repeated.
Standard vs. Cooled Radiofrequency
There are two main versions of the procedure. Traditional radiofrequency ablation heats the needle tip to 80°C for 90 seconds, creating a small, oval-shaped lesion roughly 5 millimeters across. Cooled radiofrequency ablation runs water around the electrode tip to prevent charring, which allows the heat to spread further into surrounding tissue. The result is a larger, rounder lesion about twice the diameter of a traditional one.
In early follow-up (the first four to eight weeks), both approaches deliver similar pain relief, around 55 to 60%. By two to six months, cooled ablation pulls slightly ahead, with 54% of patients still meeting the 50% relief threshold compared to about 49% for traditional. By six to twelve months, both techniques taper to around 28 to 31% relief. Cooled ablation also tends to require less fluoroscopy time, meaning less radiation exposure during the procedure. Your doctor will choose the approach based on the specific anatomy and location being treated.
Who Qualifies
Ablation isn’t the first step. Before a doctor will perform the procedure, you need to go through diagnostic nerve blocks, which are test injections of numbing medication directly onto the medial branch nerves. If a nerve block temporarily eliminates your pain, that confirms the facet joints are the source, and ablation becomes a reasonable next step.
Medicare and most insurers require at least two separate diagnostic blocks showing consistent positive results before they’ll cover the ablation. “Positive” typically means at least 80% relief of your primary pain after each block, with the duration of relief matching the type of numbing agent used. Pain scores and a functional disability assessment must be documented at baseline and after each diagnostic injection. These requirements exist because ablation only works when the pain is definitively coming from the facet joints, and diagnostic blocks are the way to prove that.
Why Pain Eventually Returns
The nerves targeted during ablation are peripheral nerves, not part of the spinal cord itself. Peripheral nerves have the ability to regenerate over time. After the heat-damaged section heals and regrows, the nerve starts transmitting pain signals again. The speed of regrowth depends partly on the size of the lesion: a larger burn area means the nerve has more distance to bridge, which generally buys more time before pain recurs. This is one reason cooled ablation, with its larger lesion, sometimes provides slightly longer relief. When the pain does come back, a repeat ablation targeting the same nerves is a well-established option that most patients tolerate just as well as the first.