A Medial Branch Block or Facet Injection is an injection that is performed to treat pain due to irritation of the spinal facet joints. If the spinal facet joints are a suspected source of your pain, a diagnostic or “test” injection is performed to determine if the spinal facet joints are a significant source of your pain. This is called a Medial Branch Block, an injection where the medial branches are numbed to “block” the nerve transmission from the targeted facet joints. If the Medial Branch Block provides significant but transient relief, you may be a candidate for Radiofrequency Ablation which provides long term relief of facet joint pain. These injections are performed under fluoroscopic guidance (x-ray) to ensure safe delivery of medication to the intended site.