What is a thoracic medial branch block?

The thoracic spine is made up of twelve vertebrae which are joined together by joints called facet joints, one on the right and left side between each vertebrae. Facet joints are felt to be frequent causes of pain in the neck and low back. Due to the stabilizing effects of the rib cage, thoracic facet pain is relatively uncommon. Each facet joint has two little nerves that detect pain. These are known as Medial Branch Nerves. In a Medial Branch Block we numb these nerves with local anesthetics. If the pain goes away with the anesthetic, then it would suggest that the pain is coming from the facet joint(s). If significant relief is obtained on two occasions from these blocks, then definitive treatment can be performed by performing a Radiofrequency Neurotomy.

What will happen during the procedure?

You will be asked to lie on your stomach and will be made as comfortable as possible. The skin will be numbed prior to the procedure. Using an X-ray machine for guidance, Dr. Harries will position a needle correctly then inject a small amount of X-ray dye. If everything appears satisfactory, the numbing medication will then be injected. This procedure will then be repeated for each nerve in turn. The location of the medial branch nerves appears in blue on the image. After the procedure you will be taken to the recovery area and observed for about 20 minutes. Your pain score will be recorded. After the procedure, it is important that you maintain a pain diary for 48 hours.

Can I be sedated for the procedure?

Sedation is best avoided as it may reduce the accuracy of this diagnostic block.

What are the risks of the procedure?

This is a very safe procedure. Feeling faint is the most common problem patients experience. Allergic reaction to medications, bruising and infection are all very rare complications.

What next if my pain is far better after the blocks?

If your pain is dramatically improved on two occasions with the blocks then you will be a candidate for Radiofrequency Neurotomy. Please see the separate leaflet on that procedure.

When can I return to work?

Most patients can return to work the following day. After any procedure it is possible to develop an increase in pain particularly from muscle spasms.

When can I drive?

You should not drive until the next day. Don’t forget to bring a driver with you on the day of your procedure.

What research is there on the effectiveness of this procedure?

Medial branch blocks are a test used to determine your suitability for radiofrequency neurotomy and so are best described as a test not a treatment. Research studies show that Radiofrequency Neurotomy is an excellent procedure for back pain, providing consistent relief has been obtained from medial branch blocks.