This page gives you information about having a nerve root injection and the risks involved.

What is a nerve root injection?

A nerve root injection is a minor procedure where local anaesthetic and steroids are injected around the nerve roots, where they branch out from the spinal cord. This is performed under the guidance of X-rays to allow us to direct the injection around the affected nerves.

These injections are used to help diagnose and treat back pain or pain in your leg, which your doctor suspects, is from compression (squashed) or irritation of the nerves.


Please inform your doctor if you have an allergy to steroids or local anaesthetic because this may alter your treatment plan.

It is also important if you are taking blood thinning medication such as warfarin or rivaroxaban, that you inform your referring doctor. They will advise you whether and when you need to stop these medications. However, if you need any further advice about stopping medication please contact us, before the procedure date, using the number shown on your appointment letter.

What will the procedure involve?

When you arrive, you will be advised to change in to a hospital gown. You will then be taken into a screening room where you will meet the radiologist and support staff. The radiologist will explain the procedure and answer any questions you may have and may ask you to sign a consent form.

You will be asked to lie on your front. The doctor will use an antiseptic solution to clean the area before a small amount of local anaesthetic is injected into the skin. Using the guidance of

X-rays a needle will then be passed close to your spine (backbone). A small amount of dye will be injected to confirm the position of the needle.

Once the radiologist is satisfied that the needle is in the correct position, a mixture of local anaesthetic and steroid will be injected. The needle will then be removed and a dressing applied.

What are the risks involved?

Having a nerve root injection is considered a minor procedure. However, it has some rare risks such as bleeding, infection and irritation to the nerves. You may experience a temporary increase in pain at the time of the procedure but this should soon settle.

You may experience headaches during and after the procedure but this should settle down within 24 hours with some pain relief, such as paracetamol.

It is difficult to predict whether the injection will improve your symptoms. Some people may find that the injection has made no difference to their pain.

There is a 1 in 5,000 risk of bruising to the nerve root. There is also a very small risk of some permanent nerve damage (about 1 in every 100,000 cases). This would result in weakness, pain and numbness in the area being treated.

Allergic reaction to the dye, steroid or local anaesthetic is extremely rare. Therefore, please let us know if you have any allergies before the procedure.

If you have diabetes the steroid in the injection may alter your blood sugar levels, so please monitor your sugar levels closely for a few days.

What will happen after the procedure?

The procedure will take about 30 minutes. You should be able to go home once you are mobile; this is normally 2 to 3 hours following the injection. There will be a small dressing placed over the injection site which can be removed after 12 hours.

We advise you not to drive for 24 hours following the injection so please arrange for someone to collect you from the hospital. We also advise that you only do light activities for 24 hours but you can return to normal activities the following day.

Follow up

An appointment will be made for you to be seen by your referring doctor after you have had the injection. We recommend that you bring with you the completed ‘pain diary’ which will be given to you before the procedure. This will not only give us useful information, but will act as a guide to plan further treatment.

Contact information

Please do not hesitate to contact the Radiology Department if you have any questions or concerns on the number shown on your appointment letter. We are open Monday to Friday between 9:00 am and 5:00 pm.

Printable version of this page

Nerve root injections GHP1559_12_22.docx Department: Radiology Review due: December 2025 PDF, 167.4 KB, 3 pages
Reference number GHPI1559_12_22
Department Radiology
Review due December 2025