Background Facet joints are pairs of small joints located on either side of our spine. They are one of the many structures that keep your spine stable and flexible allowing movements like bending and twisting. Sometimes these joints can become irritated and this can lead to pain. When this happens, the medial branch nerves transmit pain signals. Your doctor thinks this may be what is causing your pain.
What is the procedure? Medial branch blocks are diagnostic injections. This means the procedures are performed to test whether the facet joints are causing your back pain. This is done by injecting a small amount of local anaesthetic around the nerves that innervate the joints to see if this relieves your pain for a short time (usually a few hours, but sometimes up to 2 days. It is important to remember that this is a diagnostic procedure only.
What does the procedure involve? The procedure is performed as a day procedure in an operating theatre. When you arrive, the nursing staff will prepare you for theatre. In theatre, you will be asked to lie face down on the operating table. The area around the injection site will be cleaned with antiseptic and drapes will be placed around the operative area. You will be given a light sedative anaesthetic and the needles used to inject the local anaesthetic will be inserted under x-ray guidance. Once the needles are in the correct place, local anaesthetic is injected. If you are, or think you may be pregnant, please contact our office as soon as possible, as x-rays are contraindicated in this circumstance.
What happens after the procedure? After the procedure is performed, you will be monitored for a short time and given something to eat and drink before you go home. Patients are usually discharged 1-3 hours after the procedure. You must organise for someone to drive you home after the procedure, as you will be unable to drive after your sedative anaesthetic. We are interested in whether there is any pain relief, especially for the first 48 hours after the injections. Some patients may get pain relief for a few hours or a few days before the pain returns; other patients may get no relief. It is helpful if you are able to remember the extent of relief achieved and this can be assisted by the use of a pain diary. The amount of pain relief you get tells us what treatments might be effective for you in the long term. A week after the procedure you will have a follow up appointment with your doctor, at which the outcome of the diagnostic injections will be discussed and a treatment pathway planned in consultation with you. You should attend this appointment at our office.
What are the possible complications? These procedures have a very low risk of complication, but there are some that you should be aware of. Local discomfort: some patients may experience some discomfort in the area of the injection for a few hours or a few days. This is the most common complication for these procedures. Bleeding or infection: these are very rare. Please contact our office immediately if you develop fever or back pain after the procedure. If these symptoms occur outside normal office hours, please go to the nearest emergency department.