Facet Injections / Medial Branch BlocksA medial branch block is an injection of local anesthetic and cortisone placed outside the joint space near the nerve that supplies the joint called the medial branch. You may require multiple injections depending upon how many joints are involved. Facet medial branch blocks are typically ordered for patients who have pain primarily in their back coming from arthritic changes in the facet joints or for mechanical low back pain. A facet block or medial branch block may be therapeutic and/or diagnostic. One of three things may happen.
- The pain does not go away, which means that the pain is probably not coming from the blocked facet joints. This has diagnostic value
- The pain goes away and stays away for a few days to a week but the original pain comes back. This would mean the block was also of diagnostic value and the pain is probably coming from the joints.
- The pain goes away after the block and stays away for a few weeks to a few months. This means that the block was of therapeutic value and the steroid had a long lasting effect on the pain.