Chronic knee pain from osteoarthritis is one of the most common problems we see. Most people improve with exercise, weight management, and injections into the knee. But some don’t — and not everyone wants, or is suitable for, a knee replacement. For these people, a genicular nerve block offers a targeted, non-surgical way to reduce pain. So what is a genicular nerve block, does it work, and who is it for?
What is a genicular nerve block?
The genicular nerves are small sensory nerves that carry pain signals from the knee joint. A genicular nerve block is an injection of local anaesthetic — sometimes combined with a small dose of steroid — placed around these nerves. By interrupting the pain signals travelling from the knee to the brain, the block reduces pain without touching the joint itself.
It’s a well-established technique in pain medicine, and interest in it for knee osteoarthritis has grown quickly. It gives us another tool for the difficult group of patients who sit between injections and surgery.
Which nerves do we target?
Three genicular nerves are the main targets: the superior medial, the superior lateral, and the inferior medial genicular nerves. Together, these supply much of the front of the knee capsule. These nerves sit close to the small arteries and can be targeted easily.
We deliberately avoid the inferior lateral genicular nerve, as it sits close to the common peroneal nerve — the nerve that lifts the foot. Targeting only the three safe nerves is part of performing the block well.
Who is a genicular nerve block for?
We consider a genicular nerve block for people with chronic knee pain, usually from osteoarthritis, who:
- Have not improved with conservative treatment — physiotherapy, a home exercise programme, weight management, and anti-inflammatory medication
- Have not gained lasting relief from injections into the joint, such as cortisone, hyaluronic acid or PRP.
- Are not suitable for a knee replacement — often because of a high body mass index, other medical conditions, or age
- Would prefer to avoid or delay surgery
- Still have pain after previous knee surgery.y
In other words, it’s for the person who has run out of the usual options but isn’t ready for, or able to have, a joint replacement. We use a nerve block for knee arthritis.
Does a genicular nerve block work? What the evidence shows
The evidence is encouraging for a nerve block for knee arthritis, and it’s growing.
A recent case series followed six people with chronic knee osteoarthritis who had already failed physiotherapy, anti-inflammatories, and joint injections, and who weren’t candidates for a knee replacement. After a genicular nerve block with steroid, every one of them improved — reporting between 75% and 100% pain relief, lasting between 11 and 15 weeks.
Randomised trials point the same way. In one study of 90 people with chronic knee osteoarthritis, an ultrasound-guided genicular nerve block improved pain and function at one week, one month, and three months. Interestingly, it helped whether or not the pain had a “nerve” quality to it — suggesting the block works across different types of knee pain. Another randomised controlled trial compared genicular nerve blocks to fake injections and found a significant difference between groups for at least 12 weeks.
There’s also a good scientific reason to expect it to help. We increasingly recognise that knee osteoarthritis pain isn’t purely mechanical — there’s often a neuropathic (nerve-driven) component. A genicular nerve block targets exactly that pain pathway.
It’s worth being honest about the evidence too. Much of it comes from small studies and case series, and the relief is measured in weeks to months rather than years. That’s why we use the block as part of a wider plan — a bridge that reduces pain enough to let you exercise, lose weight, and stay active, rather than a permanent fix on its own.
Why ultrasound makes the difference
The genicular nerves are tiny, and they sit next to the genicular arteries and other important structures. Placing local anaesthetic and steroid accurately and safely depends entirely on seeing what you’re doing.
This is where ultrasound-guided injection is essential. Using ultrasound with colour Doppler, we identify each genicular artery, which runs alongside its nerve — so the artery acts as a landmark for the nerve. This lets us place the injection precisely around the target nerve while keeping the needle away from the blood vessels. It’s an easy procedure if done with experienced hands.
Dr Masci is a sports physician with a particular expertise in ultrasound-guided injections, having performed many thousands of procedures and taught the technique to doctors across the UK and Europe. Accurate, ultrasound-guided placement is the difference between a block that works and one that doesn’t — and it makes the procedure safer.
Genicular nerve block or radiofrequency ablation?
Genicular nerve blocks and radiofrequency ablation (RFA) work together as a two-step approach.
The block comes first. With local anaesthetic alone, it acts as a test: if your knee pain settles for a few hours afterwards, it confirms that the genicular nerves are carrying your pain — and that you’re likely to respond to longer-lasting treatment. Where we add steroid, the block itself can give relief for several weeks to a few months.
If the test block works well, radiofrequency ablation can follow. Here, a fine needle uses heat to interrupt the same nerves for much longer — relief can last up to a year. RFA suits people who responded to the block but want a more durable result, and who wish to avoid or delay surgery.
What does the procedure involve?
Genicular nerve blocks are a quick day-case procedure. We clean the skin, use ultrasound to locate each nerve, and inject a small amount of local anaesthetic — with or without steroid — around the three target nerves. It takes only a few minutes. In some cases, doctors also use a low concentration of glucose. We think glucose adds to the local anaesthetic and gives a longer-lasting effect. We often call this injection a nerve hydrodissection.
Afterwards, you rest briefly before going home. As with any injection, there are a few risks to be aware of: temporary soreness or a short-lived increase in pain, a small chance of bruising or bleeding, and a rare risk of infection. These are minimised by using ultrasound and a sterile technique. We’ll go through all of this with you before you decide to proceed.
How much do genicular nerve blocks cost?
Dr Masci performs the genicular nerve block as a one-stop appointment — consultation, diagnostic ultrasound, and the block in a single visit. At the Chelsea clinic, which is the most cost-effective location, a genicular nerve block is £450; other clinic locations cost more. See the full injection fees here and our clinic locations.
Frequently asked questions about genicular nerve blocks
How long does a genicular nerve block last?
It varies. A block with local anaesthetic alone may last only hours, and acts mainly as a test. Adding steroid typically extends relief to several weeks or a few months — studies report 11 to 15 weeks. For longer-lasting relief, radiofrequency ablation of the same nerves can help for up to a year.
Is a genicular nerve block an alternative to knee replacement?
For the right person, it can delay or avoid one. It’s particularly useful for people who aren’t suitable for surgery — because of weight, other health conditions, or age — or who want to put off a replacement. It doesn’t cure the arthritis, but it can control the pain enough to keep you active and improve your quality of life.
Does it work if I’ve already had knee injections that didn’t help?
Often, yes. A genicular nerve block works differently from an injection into the joint — it targets the nerves carrying the pain rather than the joint lining. Many people in the studies had already failed cortisone or hyaluronic acid injections before responding to a nerve block.
Is the procedure painful?
Most people tolerate it well. We use local anaesthetic, and because ultrasound lets us place the needle accurately, the block is quick. Some short-lived soreness afterwards is normal.
Why does it need ultrasound?
Because the genicular nerves are small and lie next to blood vessels. Ultrasound with Doppler lets us identify the genicular arteries as landmarks for the nerves so that we can place the injection precisely and safely. Accurate placement is what makes the block effective.
Can genicular nerve blocks be used for other knee conditions or procedures?
Yes. We sometimes use these blocks in combination with other injections such as PRP injections for knee tendons. PRP injections are often painful because we can’t use local anaesthetic. Genicular nerve blocks can provide pain relief so that PRP injections are more tolerable.
Final word from Sport Doctor London on genicular nerve blocks
A genicular nerve block is a valuable option for chronic knee pain that hasn’t settled with exercise and joint injections — especially for people who aren’t ready for, or suitable for, a knee replacement. The evidence shows meaningful pain relief lasting weeks to months, and radiofrequency ablation can extend that further. As with all injections around small nerves, accurate ultrasound guidance is what makes it work.
If you have persistent knee pain and want to know whether a genicular nerve block could help, Dr Masci can assess you in London, including ultrasound in clinic. Contact the team here or call +44 (0) 203 488 0350.
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