Medial branch block

Your health expert: Mr G Michael Hess, Consultant Orthopaedic Surgeon
Content editor review by Liz Woolf, Freelance Health Editor, June 2023
Next review due August 2026

A medial branch block is a test to see if neck and back pain come from facet joints. Your facet joints are small pairs of joints that link together the bones in your spine. If the injections help to relieve your pain, it shows that your facet joints are causing it. You may then be able to have a longer-term treatment called radiofrequency denervation.

About medial branch block injections

A medial branch block is an injection into your back, very close to spinal joints called facet joints. These are small pairs of joints that link together the bones in your spine. The facet joints are a well-known source of neck pain and headache as well as horizontal pain and stiffness across your lower back.

The injection contains a local anaesthetic, which numbs pain. A doctor places the injection very precisely into your back, close to the nerves around the painful facet joint. These nerves send pain signals to your brain. The injection will temporarily stop the signals and ease the pain. Your doctor will use X-ray guidance to ensure that the injection goes into exactly the right place.

Why you may have a medial branch block

If you have neck or back pain, your doctor is likely to suggest trying painkillers, exercise and sometimes physiotherapy.

But if these don’t help and your doctor thinks your pain might be linked to your facet joints, they may offer you a medial branch block. The most common cause of facet joint pain is osteoarthritis, which can cause your facet joints to become worn down and inflamed.

A medial branch block injection helps to prove to your doctor where your pain is coming from. If the injection gives you some pain relief, then the pain must be coming from that facet joint. How long the pain relief lasts varies from person to person. For some it’s only a few hours or days. But for others, the pain relief can last a few weeks.

If a medial branch block does help you, your doctor may suggest a longer lasting treatment called radiofrequency denervation. This uses radiofrequency waves to deactivate nerves around the facet joints that are causing the pain in your back or neck. The treatment may help to relieve pain for between six months and two years – it varies from person to person.

Not everyone can have radiofrequency denervation. It’s not suitable if you have a pacemaker or implantable cardioverter defibrillator. Your doctor may suggest you have a facet joint injection instead.

A facet joint injection is similar to a medial branch block as it contains a local anaesthetic, but it also contains a small amount of a steroid. You have the injection directly into your facet joint. The aim is to reduce inflammation in your joint space. It can help to relieve pain for a while, anything from a few weeks to a few months and, sometimes, years. You may need to have repeated facet joint injections, alongside other treatment such as an exercise programme.

Preparation for medial branch block

You'll need to go into hospital to have a medial branch block. You can have the injection and go home the same day. You won't need to stay overnight although you might have a sedative, which can make you feel drowsy.

Your hospital might ask you to fast before you go for the procedure. This means you shouldn’t eat anything for a certain amount of time beforehand. Your hospital will let you know in advance if you need to do this, and for how long.

Ask a friend or family member to take you to your appointment and drive you home. Ideally, you should also arrange for someone stay with you for the first night after your procedure.

Your surgeon will discuss with you what will happen before, during and after your procedure. If you’re unsure about anything, don’t be afraid to ask. No question is too small. It’s important that you feel fully informed and happy to give your consent for the procedure to go ahead. When you do, the doctor will ask you to sign a consent form.

What happens during a medial branch block?

A pain specialist doctor will give you a medial branch block. You’ll need to lie on your front if you’re having the injection into your lower back; on your side if the injection is into your neck. They may offer you sedation to help you relax. Once you’re ready, they will clean your skin and inject a local anaesthetic to numb any pain while you're having the procedure. The local anaesthetic may sting a little but this won’t last long.

Your pain specialist will use X-ray images to help them find the right spot on your back or neck. They may inject a type of dye called contrast medium to make sure the needle is in the right place.

When the needle is in place, the doctor gives the injection. This delivers local anaesthetic around the nerves in your facet joint.

It only takes a few minutes to give you the injection. The whole procedure should take around 20 minutes, including having the X-rays taken.

Aftercare for medial branch block

After the procedure, you go to a recovery room. Health professionals will monitor you there for a short time, before you leave. At first, they may ask you to lie flat. They’ll check your blood pressure or pulse and ask how you feel.

You can usually go home a few hours after the procedure. You'll need somebody to drive you home – you won't be able to drive yourself. Ideally, you should also have someone stay with you for the first night after your procedure, especially if you’ve had sedation.

Your doctor may ask you to keep a diary of your pain symptoms for few days after you go home. This helps to show how much the injections have helped and whether further treatment will help.

You can continue to do all your normal activities when you get home, but avoid anything too strenuous for the first couple of days. As your pain improves, you should gradually increase the amount of exercise you do. It’s important not to overdo it, but exercise will improve your muscle tone and help to make your back stronger. Ask your doctor if you’re unsure about anything. For some more detail, see our section on questions to ask your doctor.

Side-effects of medial branch block

Side-effects are effects that you may get after having the procedure. They are mostly temporary. After a medial branch block, you may have some tenderness or bruising where you had the injection. This usually gets better within a few days.

Complications of medial branch block

Complications are when problems occur during or after the procedure. Possible complications of a medial branch block include:

infection
bleeding
injury to a nerve
an allergic reaction to the local anaesthetic or contrast media

After you’ve gone home, contact the unit where you had the procedure if you:

develop a headache
have any increased or unusual pain in the area where you had the injection
have any signs of infection around the injection site – for example, redness, heat or swelling

Considerations for medial branch block

It’s important to discuss the procedure with your pain specialist. You need to be able to make an informed decision about whether to go ahead with a medial branch block. There are some things to consider before deciding if this is the right treatment for you.

A medial branch block can help your doctor to find the cause of your neck or back pain. This means they may be able to offer you certain treatments that are more likely to help you. If these treatments reduce the pain in your neck or back, it can make it easier to get about and improve your quality of life. You may find it easier to do physiotherapy or take part in an exercise programme. This may help to improve your condition in the long term.

Any pain relief you get from a medial branch block will be temporary. It’s a test used to confirm where the pain comes from, not a cure for the pain. There’s also a very small risk that you’ll have some problems during or after the operation. For more information, see our sections on side-effects and complications.

Questions to ask your doctor

Have a think about any questions you would like to ask your doctor before you decide whether to have a medial branch block or not. Here are some example questions you might like to ask.

What can I expect to happen after I’ve had a medial branch block?
Will I be able to exercise after the injection? Are there any types of exercise it's best not to do?
How can I tell if my injection has worked to show that my neck and back pain comes from my facet joints? How long will it take until I know if it's worked?
What is the likelihood of the procedure working?
How will you reduce the risk of complications?
What treatment options do I have to relieve my pain?
Should I have physiotherapy or some other rehabilitation after having my injection?

Looking for physiotherapy?

You can access a range of treatments on a pay as you go basis, including physiotherapy.

To book or to make an enquiry, call us on 0370 218 6528^∧

Find out more about physiotherapy

The main reason for having this done is to diagnose where pain is coming from rather than to treat it. But when medial branch block relieves pain, how long this lasts varies. It could be anything from a few hours to a few weeks.

For more information, see our section on why you may have a medial branch block.

If a medial branch block helps you, your doctor may suggest other treatments. This could include radiofrequency ablation, physiotherapy, and an exercise programme.

For more information, see our section on why you may have a medial branch block.

You have a medial branch block as an outpatient. You can usually go home shortly afterwards, although this depends on your overall recovery.

For more information, see our section on aftercare for medial branch block.

After your procedure, you will be in a recovery area for a short while. How long this is for varies between people and also depends on whether or not you had any sedation. You should be able to go home after a couple of hours at most.

For more information, see our section on aftercare for medial branch block.

Medial branch block isn’t usually painful. You’ll have local anaesthetic into the skin of your back and this can sting a bit. You may feel some pressure as the injection goes in. Some people have a sedative, which will make you drowsy during the procedure.

For more information, see our section on what happens during a medial branch block.

More on this topic

Did our Medial branch block information help you?

We’d love to hear what you think.^∧ Our short survey takes just a few minutes to complete and helps us to keep improving our health information.

^∧The health information on this page is intended for informational purposes only. We do not endorse any commercial products, or include Bupa's fees for treatments and/or services. For more information about prices visit: www.bupa.co.uk/health/payg

Complete 2 mins survey

This information was published by Bupa's Health Content Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals and deemed accurate on the date of review. Photos are only for illustrative purposes and do not reflect every presentation of a condition.

Any information about a treatment or procedure is generic, and does not necessarily describe that treatment or procedure as delivered by Bupa or its associated providers.

The information contained on this page and in any third party websites referred to on this page is not intended nor implied to be a substitute for professional medical advice nor is it intended to be for medical diagnosis or treatment. Third party websites are not owned or controlled by Bupa and any individual may be able to access and post messages on them. Bupa is not responsible for the content or availability of these third party websites. We do not accept advertising on this page.

Lumbosacral facet syndrome workup. Medscape. emedicine.medscape.com, updated November 2018
Lumbar facet joint syndrome – injection treatment. British Association of Spine Surgeons. Spinesurgeons.ac.uk, last updated August 2021
Low back pain and sciatica in over 16s: assessment and management. National Institute for Health and Care Excellence (NICE). nice.org.uk, last updated December 2020
Facet joint medial branch blocks for the treatment of pain. Faculty of Pain Medicine of the Royal College of Anaesthetists. fpm.ac.uk, last reviewed September 2019
Du R, Xu G, Bai X, et al. Facet joint syndrome: pathophysiology, diagnosis, and treatment J Pain Research 2022; 15:3689–710. doi: 10.2147/JPR.S389602
Liu M, Shaparin N, Nair S, et al. Chronic low back pain: the therapeutic benefits of diagnostic medial branch nerve blocks. Pain Physician 2021: 24:E521–8
Facet joint rhizolysis/radio frequency lesioning (denervation) for the treatment of pain. Faculty of Pain Medicine of the Royal College of Anaesthetists. fpm.ac.uk, last reviewed September 2019
Bernardes ALPR, Correa RF, Trajano LADSN, et al. Lumbar facet syndrome and the use of radiofrequency ablation technique as an alternative therapy: a systematic review. Rev Bras Ortop (Sao Paulo). 2023 May 25; 58(2):199-–205. doi: 10.1055/s-0043-1768695.
Cohen SP, Bhaskar A, Bhatia A, et al. Consensus practice guidelines on interventions for lumbar facet joint pain from a multispecialty, international working group. Region Anesth Pain Med 2020; 45:424–67
Conger A, Burnham T, Salazar F, et al. The effectiveness of radiofrequency ablation of medial branch nerves for chronic lumbar facet joint syndrome in patients selected by guideline-concordant dual comparative medial branch blocks. Pain Med 2019; 21(5):902–9. doi.org/10.1093/pm/pnz248
Paraspinal injections – facet joint and nerve root blocks. Medscape. emedicine.medscape.com, last updated January 2019
Kubulus C, Schmitt K, Noemi A, et al. Awake, sedated or anaesthetised for regional anaesthesia block placements? A retrospective registry analysis of acute complications and patient satisfaction in adults. Eur J Anaesth 2016; 33(10): 715–24
Sedation explained. Royal College of Anaesthetists. rcoa.ac.uk, published June 2021
Medial Branch Block. Royal National Orthopaedic Hospital. roh.nhs.uk, accessed June 2023
Facet joint injections and medial branch blocks. Torbay and South Devon NHS Foundation Trust. torbayandsouthdevon.nhs.uk, published May 2021
Personal communication, Mr Michael Hess, Consultant Orthopaedic Surgeon, August 2023

Our information has been awarded the PIF tick for trustworthy health information.