Facet joints are small joints at each segment of the spine that provide stability and help guide motion. The facet joints become painful due to spinal injury, mechanical stress to the spine, and/or arthritis. There are three types of facet joints. Cervical facet joints cause pain to the head, neck, shoulder, and/or arm. Thoracic facets cause pain to the upper back. Lumbar facet pain is usually felt in the lower back, hip, buttock, and/or leg. During the procedure, a local anesthetic is used to reduce pain and then a steroid injection is placed directly into the facet joint or medial branch. In addition to pain relief by decreasing the inflammation in the joint, these injections are used to diagnostically determine if the facet joints are the cause of the pain.