Radiofrequency Ablation

Overview

Radiofrequency ablation, sometimes called radiofrequency neurotomy, is a minimally invasive procedure that uses heat generated by radio waves to disable the small sensory nerves that carry pain signals from a joint to the brain. In the spine, it is most often used for two sources of pain: the facet (zygapophyseal) joints that link adjacent vertebrae in the neck or low back, and the sacroiliac (SI) joints that connect the pelvis to the base of the spine. In both cases, the target is never the joint itself or the spinal cord, but a specific, well-mapped sensory nerve, the medial branch nerve for facet joints or the lateral branch nerves for the SI joint, that does not control muscle movement.

Because RFA interrupts a pain signal rather than repairing tissue, it does not cure arthritis or joint degeneration. What it offers is a meaningful window, typically many months to over a year, of reduced pain that can make physical therapy, exercise, and daily function more tolerable. It is performed with a thin needle under x-ray or ultrasound guidance, usually as an outpatient procedure with local anesthesia and light sedation.

When it's recommended

RFA is considered for chronic facet or SI joint pain that has not responded adequately to conservative care such as physical therapy, activity modification, and medication. It is not a first-line treatment. Before RFA is offered, patients almost always undergo one or two diagnostic blocks, small injections of numbing medication placed directly at the suspected nerve or joint, to confirm that this specific structure is genuinely the source of pain. A block is considered positive when it produces substantial, if temporary, relief that closely tracks the numbing medication's expected duration. Requiring this confirmation step helps avoid ablating a nerve that was never the real problem.

RFA is a reasonable option for people whose pain returned after a previously helpful joint injection wore off, or who have known facet or SI joint arthritis confirmed by exam and imaging alongside a positive block. It is generally not appropriate for pain caused primarily by disc problems, nerve root compression, infection, fracture, or tumor, since ablating a joint's sensory nerve will not relieve pain coming from a different source.

How it works

During the procedure, the patient lies face down and the skin over the target area is numbed. Using continuous x-ray (fluoroscopic) guidance, the physician advances a thin, insulated needle so its tip sits precisely alongside the target nerve, either the medial branch nerve near a facet joint or the lateral branch nerves near the SI joint. Before delivering any heat, the physician typically performs sensory and motor stimulation tests through the needle to confirm correct placement and to make sure a motor nerve is not nearby, then injects local anesthetic to keep the patient comfortable.

Once position is confirmed, radiofrequency current heats the needle tip to a temperature that disrupts the nerve's ability to conduct pain signals, usually for 60 to 90 seconds per nerve. Multiple nerve levels are often treated in one session, since each facet or SI joint receives sensory branches from more than one spinal level. Three variations exist: conventional RFA uses a standard heated needle tip; cooled RFA circulates water inside the probe so it can create a larger, more spherical heat lesion, which is frequently used at the SI joint because its sensory nerves are more spread out and variable in location; and pulsed RFA delivers short bursts of heat with cooling intervals in between, staying below the temperature threshold that destroys nerve tissue, which some physicians use near motor nerves or as a gentler alternative. The entire procedure usually takes 30 to 60 minutes.

Preparing for the procedure

Before RFA, patients typically need documented positive diagnostic blocks on file, since most insurers and protocols require this evidence of the correct pain source. A medication review is standard, as blood thinners, aspirin, and certain supplements often need to be paused beforehand under the prescribing physician's guidance. Patients are usually asked to arrange a ride home, since sedation may be used, and to eat a light meal or fast for a few hours beforehand per the facility's instructions. Loose, comfortable clothing that allows access to the back is helpful, and most patients can plan to take it easy for the rest of the day but do not need to arrange extended time off work.

Recovery and aftercare

Most patients go home the same day. Some soreness, numbness, or bruising at the needle sites is common for a few days to a couple of weeks as the nerve tissue breaks down, and it is common for pain to temporarily flare before it improves. Meaningful pain relief often becomes noticeable within one to three weeks, once the treated nerve has fully stopped conducting signals. Light activity is usually fine right away, with a gradual return to normal exercise and physical therapy over the following days to weeks as tolerated, guided by the treating physician.

Because the target nerve regenerates over time, relief is not permanent. Studies generally report benefit lasting about 6 to 18 months, with many patients experiencing roughly 9 to 12 months of meaningful relief, though this varies by individual and by joint treated. When pain gradually returns as the nerve regrows, repeat RFA is a standard and often equally effective option, and many patients continue the procedure periodically as part of long-term pain management.

Risks and considerations

RFA is generally well tolerated with a low rate of serious complications. Reported risks include temporary increased pain or numbness at the treated area, minor bleeding or bruising, infection at the needle site, and, uncommonly, unintended effects on a nearby nerve if it carries motor fibers, which can cause temporary weakness or altered sensation. Because the procedure relies on precise needle placement and confirmed nerve mapping, it is performed under image guidance by physicians experienced in the technique.

Since RFA works by disabling a pain-carrying nerve rather than addressing the underlying joint arthritis or instability, it does not stop the joint from degenerating further, and pain from other sources, such as a disc or nerve root, will not respond to this treatment. Success depends heavily on accurate patient selection through diagnostic blocks; skipping or misreading this confirmation step is a common reason RFA fails to help. Patients considering RFA should discuss with their physician whether their pain pattern, exam findings, and block response genuinely point to the facet or SI joint as the source before proceeding.