1. What Is Radiofrequency Ablation?

Radiofrequency ablation is a procedure that targets small sensory nerves that carry pain messages from a painful structure (such as a spinal joint or an arthritic knee) to the spinal cord and brain. A thin needle is placed next to these nerves, and a special device sends radiofrequency energy through the needle tip. This creates a small area of heat in the tissues immediately around the tip, usually around 80°C for conventional RFA.

The heat causes a controlled injury to the pain-carrying portion of the nerve. This disrupts or “switches off” its ability to send pain signals for a period of time. The nerve itself is not removed, and it can slowly regrow over months. If it does, the pain may gradually return, and the procedure can sometimes be repeated.

Common targets include:

• Medial branch nerves – tiny nerves that carry pain from the facet joints in the spine (in the neck, mid-back, and lower back).
• Genicular nerves – nerves around the knee joint that carry pain from knee osteoarthritis or after knee surgery.
• Nerves around the sacroiliac (SI) joint – where the spine meets the pelvis, a common source of lower back and buttock pain.
• Other sensory nerves – for example, nerves around the shoulder in some types of shoulder pain.

RFA is usually done by pain specialists, anaesthetists, or interventional radiologists who are trained in image-guided procedures.

2. Why Might You Be Offered RFA?

RFA is usually considered when you have persistent, localised pain that is thought to come from a specific joint or set of structures, and other treatments (such as medicines, physiotherapy, and injections) have not provided enough relief.

Conditions where RFA is commonly used

• Facet joint pain in the spine – in the neck (cervical), mid-back (thoracic), or lower back (lumbar). Facet joints are small joints at the back of the spine that help guide movement. Arthritis or irritation in these joints can cause localised back or neck pain, often worse with certain movements or prolonged standing.
• Sacroiliac (SI) joint pain – pain around the dimples at the base of the spine, sometimes spreading into the buttocks or upper legs. SI joint pain can follow injury, pregnancy, or simply develop over time.
• Knee osteoarthritis – long-lasting knee pain due to wear-and-tear or degenerative changes in the knee joint. RFA of the genicular nerves can sometimes help people who are not ready for, or do not want, knee replacement surgery, or who still have pain after surgery.
• Shoulder pain – in some cases of shoulder osteoarthritis or pain after injury or surgery, targeting certain sensory nerves around the shoulder may help.

Who RFA may be suitable for

• You have chronic pain (usually lasting 3–6 months or longer) in a fairly specific area.
• Your team suspects the pain is coming from a joint or structure that can be targeted by RFA (for example, facet joints, SI joint, or knee joint).
• You have not had enough relief from other treatments such as medicines, physiotherapy, or steroid injections.
• You are able to lie still for the procedure and follow instructions.
• You have had diagnostic nerve blocks (see below) that strongly suggest those nerves are the main source of your pain.

Who RFA may not be right for

RFA is less likely to help if your pain is very widespread, mainly muscular, or coming from nerves that are already badly damaged (for example, some types of nerve pain or neuropathy). It is also not a treatment for conditions like cancer pain spread widely in the body, or for pain that is mostly related to mood, sleep, or stress (although these factors influence how all pain feels).

The importance of diagnostic nerve blocks

Before offering RFA, many pain services use diagnostic nerve blocks to test whether the target nerves are truly responsible for your pain. This is strongly supported by expert guidelines and evidence reviews.

In a diagnostic block, a small amount of local anaesthetic (numbing medicine) is injected near the suspected nerves, such as the medial branch nerves for suspected facet joint pain. If your pain improves significantly for the few hours while the anaesthetic is working, this suggests those nerves are involved. If there is little or no relief, RFA is less likely to help.

Some centres require two positive diagnostic blocks (on different days) before going ahead with RFA. This is because research shows that patients with clear, repeatable benefit from blocks are more likely to get good results from RFA.

3. Types of Radiofrequency Ablation

There are several types of RFA. They all use radiofrequency energy, but in slightly different ways. Your clinician will choose the type they feel is most appropriate for your condition and their experience.

Conventional (thermal) RFA

This is the most widely used form of RFA for spinal facet joints and many other targets. The tip of the needle is heated to a constant high temperature (typically around 80°C) for a set time, often 60–90 seconds. This produces a small, oval-shaped lesion in the tissue, which interrupts the pain-carrying part of the nerve.

Conventional RFA has been studied for many years and is the technique most of the evidence relates to, especially for facet and SI joint pain.

Pulsed radiofrequency (PRF)

In pulsed RFA, short bursts of radiofrequency energy are delivered with breaks in between, keeping the temperature much lower (often below 42°C). The idea is that this may change how the nerve behaves and carries pain without causing the same level of heat injury as conventional RFA.

PRF is sometimes used when clinicians want a potentially gentler approach, or when nerves are close to important motor (movement) fibres. However, the evidence base for PRF is generally smaller and more mixed than for conventional thermal RFA.

Cooled radiofrequency ablation

Cooled RFA uses special needles with internal cooling. Water circulates through the needle tip to keep its surface temperature lower, even though the surrounding tissues are still heated. This can create a larger lesion in the target area while protecting the needle tip itself.

Cooled RFA is used in some centres for SI joint pain and knee osteoarthritis. Some studies suggest it can provide good relief for these conditions, though availability varies by region and service, and long-term data are still evolving.

4. What Happens on the Day of the Procedure?

Exact details vary between hospitals and clinics, but the general steps are similar.

Arrival and preparation

• Arrival and check-in – You will usually come to a day-case unit. Staff will confirm your details, medicines, allergies, and that you have followed any fasting instructions.
• Consent – The clinician will explain the procedure, benefits, and risks again and answer your questions. You will sign a consent form if you are happy to go ahead.
• Changing and monitoring – You may be asked to change into a gown. A nurse will check your blood pressure, pulse, and oxygen levels. A small cannula (drip) may be placed in your hand or arm in case you need medicines through a vein.

Positioning and skin preparation

• You will be helped into the appropriate position on the X-ray or procedure table – for example, lying on your tummy for lumbar facet or SI joint RFA, or on your back for knee RFA.
• The skin over the treatment area will be cleaned with antiseptic to reduce infection risk, and sterile drapes may be placed around the area.

Local anaesthetic and imaging guidance

• The clinician will use imaging guidance – usually fluoroscopy (a type of live X-ray), and sometimes ultrasound or CT – to plan exactly where to place the needle.
• The skin and tissues down to the target area are numbed with local anaesthetic using a small injection. This can sting or burn briefly, then the area should become more comfortable.

Needle placement

Once the area is numb, the specialist passes a thin RFA needle through the numbed skin and guides it carefully into position next to the target nerve, using repeated X-ray views and their knowledge of anatomy.

You might feel some pressure, pushing, or a dull ache as the needle is positioned, but sharp pain should be reduced by the local anaesthetic. If anything is very uncomfortable, you can tell the team so they can pause or give more local anaesthetic.

Sensory and motor testing

Before doing the actual ablation, the clinician often performs test stimulation through the needle:

• Sensory testing – a small current is passed to see if it produces a familiar sensation where you usually feel pain (for example, in the lower back or knee). This helps confirm the needle tip is in the right place next to the pain-carrying nerve.
• Motor testing – a different type of current checks for muscle twitches. If strong twitches occur in nearby muscles, it may mean the needle is too close to motor (movement) nerves, and the position can be adjusted. This reduces the risk of affecting movement.

The ablation itself

• Once the needle is correctly placed and testing is reassuring, a small amount of local anaesthetic may be given again through the needle.
• The RFA machine is then activated for a set time, depending on the technique being used.
• You may feel a warmth, pressure, or deep ache in the area while the lesion is being made. Some people find this uncomfortable but manageable; others feel very little.
• For multiple nerves (for example, along several levels of the spine or around the knee), the process is repeated with one or more needles.

Recovery and going home

• After the procedure, the needles are removed and a small dressing or plaster is applied.
• You will be taken to a recovery area and monitored for a short time (often 30–60 minutes) until you are stable and feel ready to go home.
• Most people go home the same day. You will usually need someone to take you home and stay with you initially, especially if you have had any sedation.
• You will be given written instructions about activity, wound care, and when to seek help.

5. Does It Hurt?

It is completely understandable to worry about pain during a procedure that is meant to treat pain. Experiences vary from person to person, but there are some common patterns.

During the procedure:

• The local anaesthetic injections can sting or burn for a few seconds, then the area usually goes numb.
• As the needle is positioned, you might feel pressure, pushing, or a dull ache. Sharp pain should be minimised, and you can always ask for more local anaesthetic.
• During test stimulation, you may feel a brief buzzing, tingling, or reproduction of your usual pain. This is expected and helps confirm the right spot.
• During the ablation phase, some people feel warmth or a deep ache. Others have only mild discomfort. The team can pause, adjust position, or give more local if needed.

Some centres also offer mild sedation (medicines that help you relax and feel drowsy but still able to respond). Whether this is available depends on local practice, your health, and the type of procedure.

After the procedure:

• It is common to have soreness, bruised feeling, or stiffness around the treatment area for several days, sometimes up to two weeks.
• Your usual pain may flare temporarily before it settles.
• Simple pain relief (such as paracetamol, and sometimes anti-inflammatory medicines if safe for you) and gentle movement usually help.

Many people describe the overall experience as uncomfortable rather than severely painful, and the procedure is usually brief. Let your team know your worries beforehand so they can plan the best approach for you.

6. What to Expect Afterwards

Immediately after

• You may feel numbness or temporary weakness in the area if local anaesthetic was used near motor nerves. This usually wears off within hours.
• The treatment area can feel sore or bruised for several days. This is part of the healing process around the treated nerves.
• You will be given advice about driving, work, and activity. Often, driving is not recommended for 24 hours if you have had sedation.

Onset of benefit

RFA does not usually give instant long-term relief. In fact, pain can be a little worse at first. Most people who benefit notice an improvement within 2–4 weeks, although for some it may be earlier or a bit later.

It is helpful to keep a simple pain and activity diary in the first weeks, so you and your team can see how things are changing over time.

How long might relief last?

Relief from RFA is usually temporary but can be significant. Many studies and clinical services report:

• Pain relief for around 6–12 months in many people who respond well.
• Some people have benefit for up to 18 months or longer, especially when the procedure is carefully targeted and combined with rehabilitation.
• Others may have only modest or short-lived improvement, or no benefit at all.

Over time, the treated nerves tend to regrow. As they do, pain signals can return. If you had clear benefit the first time, repeating the procedure may be considered.

Repeat procedures

Guidelines and expert reviews (including those cited by sources such as Johns Hopkins Medicine and Cleveland Clinic) note that RFA can be repeated if pain returns and you previously had good relief. The timing depends on:

• How long the first treatment helped.
• How much function and quality of life improved.
• Whether your underlying condition or general health has changed.

Your pain team will weigh up the likely benefits and risks of repeating the procedure and may also suggest combining it with physiotherapy, strengthening, weight management, or pacing strategies to maximise and maintain improvements.

7. How Well Does It Work? (The Evidence)

Research on RFA has grown steadily over the past few decades. Large hospitals and expert organisations such as Johns Hopkins Medicine and the Cleveland Clinic describe RFA as a useful option for carefully selected people with certain types of back, neck, joint, and nerve-related pain.

StatPearls (NBK482387) on the NCBI Bookshelf summarises RFA as an established treatment for facet joint pain and other conditions when patients are selected using diagnostic blocks. It highlights that success is more likely when the pain source is clearly identified and when procedures follow strict technical standards.

More recent scientific papers, including articles available on PubMed Central (such as PMC11445673 and PMC12790810), have looked at RFA for different conditions, including spinal and joint pain. Overall, they suggest that RFA can reduce pain and improve function for many patients, particularly in the short and medium term.

Facet joint and SI joint pain

Recent systematic reviews up to 2024 have found that RFA provides meaningful relief for a proportion of people with facet joint and sacroiliac (SI) joint pain, especially when:

• Diagnostic medial branch or lateral branch blocks clearly reduced pain beforehand.
• Procedures were guided carefully with imaging and test stimulation.
• Patients were followed up with rehabilitation and self-management strategies.

Cochrane reviews (well-respected, independent evidence summaries) have generally found moderate evidence for short-term benefit of RFA in facet joint pain, with more mixed results in the longer term and across different studies. For SI joint pain, evidence is also emerging and suggests benefit in selected patients, particularly with cooled RFA, but high-quality long-term data are still limited.

Knee and other joint pain

Studies of RFA for knee osteoarthritis generally show reductions in pain and improved function for many patients over 6–12 months, especially when they are not ready for or cannot have knee replacement. Some evidence also supports RFA for certain types of shoulder and hip pain, but the number of good-quality trials is smaller.

Being honest about limitations

It is important to recognise that:

• Not everyone benefits – even with positive diagnostic blocks, a proportion of people get little or no improvement.
• Long-term evidence (beyond 1–2 years) is more limited and mixed. Some people need repeat procedures; for others, pain may return or change over time.
• Studies vary in technique, patient selection, and outcome measures, which makes it harder to compare and to predict exactly how much benefit an individual will get.

Overall, the evidence suggests that RFA is a reasonable option for well-selected patients with confirmed facet or SI joint pain and some other joint pains, particularly when part of a broader plan that includes movement, strengthening, and support for sleep and mood.

8. Risks and Side Effects

RFA is generally considered safe when performed by experienced clinicians using imaging guidance, and serious complications are rare. However, like any procedure, it has risks and side effects.

Common and expected effects

• Post-procedure soreness – aching, bruised feeling, or tenderness at the needle sites or deeper in the treated area. This usually improves over days to a couple of weeks.
• Temporary increase in pain – your usual pain may flare for a short time before any benefit appears.
• Temporary numbness or altered sensation – especially near the skin or around the treated area, which typically settles as tissues heal.

Less common risks

• Bleeding or bruising at the injection site, particularly if you are on blood-thinning medicines.
• Infection at the skin or deeper tissues. This is uncommon, and sterile techniques are used to reduce the risk. Seek help if you notice increasing redness, warmth, swelling, or fever.
• Allergic reaction to local anaesthetic, antiseptic, or other medicines used, which is rare but can be serious. Tell your team about any past reactions.

Rare but more serious complications

• Nerve damage – if heat affects motor nerves or other important structures, it could cause weakness, numbness, or unusual sensations. This is rare, and careful testing and imaging are used to minimise the risk.
• Deafferentation pain – in very rare cases, disrupting a nerve can lead to a different type of pain (often burning or shooting), sometimes called deafferentation pain. This is unusual but important to mention.
• Damage to nearby structures – such as blood vessels, the lining around the lungs (causing pneumothorax in some upper back or chest procedures), or other tissues. These complications are rare.

Remember that RFA does not remove the nerve completely; it disrupts its ability to carry pain for a time. The nerve can regrow, which is why pain may return in the future. Your team will discuss how these risks apply to your individual situation.

9. Who Should Not Have RFA?

Your clinician will check for reasons why RFA might not be safe or suitable for you. These can include:

• Active infection – either at the planned needle site or a significant infection elsewhere in the body.
• Bleeding disorders or blood-thinning medicines that have not been appropriately managed. You may need to adjust or pause some medicines under medical supervision before the procedure.
• Pregnancy – because of the use of X-rays (fluoroscopy) and limited data, RFA is usually avoided in pregnancy unless there are compelling reasons.
• Uncontrolled medical conditions – such as severe heart or lung disease, which could make any procedure riskier.
• Certain implanted devices – for example, pacemakers or other electrical implants. Special precautions may be needed, and your cardiology or device team may need to be involved.
• No diagnostic blocks or negative blocks – if you have not had appropriate diagnostic nerve blocks, or they did not improve your pain, RFA is less likely to help and is usually not recommended.
• Inability to cooperate or lie still – severe anxiety, movement disorders, or cognitive issues may make it hard to perform the procedure safely without extra support or sedation.

These are general points; your pain team will discuss your individual risks, medicines, and other health conditions before deciding if RFA is appropriate.

10. Questions to Ask Your Pain Team

Going into the procedure with clear information can make it less frightening and help you decide whether it is right for you. You might find it helpful to bring this list, add your own questions, and take notes during the consultation.

• Diagnosis and expectations
  • What do you think is causing my pain?
  • Which specific nerves or joints are you planning to target?
  • What level of pain relief and functional improvement would you consider a “successful” outcome for me?
• Evidence and alternatives
  • How well does RFA work for people with my condition and in my age group?
  • Are there other non-surgical options we should try or continue alongside RFA?
  • What would happen if I decide not to have RFA?
• Procedure details
  • Which type of RFA (conventional, pulsed, cooled) will you use, and why?
  • Will I have sedation as well as local anaesthetic?
  • How long will the procedure take, and will I be able to go home the same day?
• Risks and safety
  • What are the main risks for someone with my medical history?
  • Do I need to stop or adjust any medicines, especially blood thinners, before the procedure?
  • How will you reduce the risk of nerve damage or other complications?
• Aftercare and follow-up
  • How long should I expect soreness or flare-ups to last afterwards?
  • When should I contact you if I am worried about my symptoms?
  • Will I be offered physiotherapy or rehabilitation to help me make the most of any pain relief?
  • If RFA helps, how soon could it be repeated if the pain returns?

You are entitled to take time to think, ask for written information, or seek a second opinion if you are unsure. Your comfort and understanding are an important part of good care.

11. Key Points

• Radiofrequency ablation (RFA) uses heat from radio waves to temporarily disrupt specific sensory nerves that are carrying pain signals from joints like the spine, SI joint, or knee.
• It is usually offered to people with persistent, localised pain where tests and examinations point to a clear source that can be targeted.
• Diagnostic nerve blocks are an important step to check that the right nerves have been identified before going ahead with RFA.
• On the day, the procedure involves local anaesthetic, image guidance (often fluoroscopy), careful needle placement, test stimulation, and then the ablation itself, followed by a short recovery period.
• Most people experience some temporary soreness or a flare in pain after the procedure, with potential benefits usually appearing over 2–4 weeks.
• For those who respond, relief often lasts 6–18 months, though results vary and nerves can regrow, meaning pain may return.
• Evidence from reputable sources (including Johns Hopkins Medicine, Cleveland Clinic, StatPearls, and recent systematic reviews) supports RFA as a helpful option for well-selected patients, especially for facet and SI joint pain, though long-term data are mixed.
• Complications are uncommon but include infection, bleeding, and, rarely, more serious nerve-related problems. Your individual risks depend on your health and the area being treated.
• RFA is only one part of pain management. Combining it with movement, strengthening, pacing, and support for sleep and mood usually gives the best chance of improving quality of life.