The term facet block refers to a group of injections used to treat arthritic conditions within the spine. Facet blocks can be performed in the neck, mid back, and lower back. Facet joints are the paired joints on each side of the spine that run from the top of the neck to the base of the spine where it joins with the pelvis. The facet joints are in the back of the spine, the discs are in the front of the spine. These joints can become arthritic related to age and degeneration and they commonly become irritated and damaged from trauma. When the disc at a particular level starts to degenerate or herniate, the facet joints simultaneously degenerate and often become another painful part of the problem. Facet blocks are performed via two different techniques. The first type is referred to as a facet joint injection and is performed by placing medication directly into the joint. The second type is called facet mapping and this injection maps the nerves that go to the joint.

 

1. Facet joint injection – In this approach a needle is placed directly inside the joint, dye is injected in the joint to confirm placement, and then local and steroid is injected within the joint. The local anesthetic provides some temporary relief and the steroid reduces inflammation in the area, hopefully providing long term relief.
2. Facet mapping – In this situation, the nerves that innervate the joint are blocked with local anesthetic to see if there is a change in symptoms (and typically steroid is added to try and achieve a prolonged effect by reducing the inflammation in the area). This approach frequently provides extended relief similar or better than intra-articular joint injections. A mapping procedure must always be performed prior to performing a more long lasting treatment to the facet joints, radiofrequency ablation. This provides confirmation that the nerves causing the patient’s pain are correctly identified before they are blocked on a more long term basis. Today most facet blocks are done via a mapping approach.