Medial branch nerves are the very small nerve branches that communicate pain caused by the facet joints in the spine.

These nerves do not control any muscles or sensation in the arms or legs. They are located along a bony groove in the low back and neck and over a bone in the mid back. The purpose of this procedure is to determine if the facet joints are painful. There is no other test which gives this information. CT Scans and MRI scans will not tell if the facet joints are painful. This test is only temporary, but if it shows the joints to be painful, a long term procedure (radio frequency lesioning) can be performed.

Procedure Overview

The medial branch block injection is an outpatient procedure. The patient is placed on the x- ray table and positioned in such a way that the physician, using x-ray guidance, can best visualize the bony areas where the medial branch nerves are located. The skin is scrubbed with prep solution. Next, the physician numbs a small area of skin with numbing medicine. After the numbing medicine has had time to take effect, the physician uses x-ray guidance to direct a very small needle near the specific nerve being tested. A small amount of contrast (dye) is injected to ensure proper needle position. Then, a small amount of numbing medicine (anesthetic) is injected.

After the Procedure

After your discharge from the pain center, it is very important that you engage in activities which would normally provoke your pain. If you do not, the test will not give a valid result. You will be provided a pain diary and document your pain every hour for 6 to 8 hours. If you feel a significant decrease in pain your test is a success. Remember, this is a temporary procedure and return of your pain is expected. Please note when your pain returns. The results of this test will then determine what further diagnostic or therapeutic procedures will be needed.

Watch this short video below to learn more about the procedure.