A facet joint is the point between vertebrae that allows the spine to twist and bend. This procedure is used to diagnose which facet joint is causing a patient pain. The procedure begins with the patient laying face down. The physician will administer a numbing anesthetic for the skin and tissue around the affected joint. A contrast dye is then injected to pinpoint the area of injection. Using live x-ray images from the fluoroscope, the physician will confirm the location and position of the needle. Once this is done the medication will be fed through an attached syringe and will bathe the small branch nerves that generally carry signals for the facet joint, numbing all feeling. If the patient feels relief from this injection, the physician will inject a longer lasting anesthetic. If pain is still felt by the patient, other facet joints will need to be tested to identify which is the cause of pain.