What is a Facet Block?

A facet block is a diagnostic procedure used to pinpoint the location of pain and nerve damage in the spine. Specialists often have trouble discovering the exact nature of their patients' chronic back pain, as routine x-rays and other diagnostic imaging tests may not reveal obvious damage to a particular area. Using a real-time x-ray device called a fluoroscope, a physician injects a localized anesthetic or anti-inflammatory steroid solution into a facet joint to see if it relieves pain. Based on the patient's response, the doctor can determine the severity of the injury and make the best treatment decisions.

Facet joints are found in pairs at each vertebra in the spine. Direct injuries or chronic conditions such as arthritis can deteriorate cartilage tissue in the joints and potentially result in bulging disks. As a result, a person can experience dull aches, sharp acute pains, and loss of flexibility in the spine. If nearby nerves are compressed, tingling or numbness can affect the legs or torso. A facet block is performed to determine which facet joint or joints are involved.

In most cases, a facet block is performed at a general hospital or outpatient surgical center. A doctor first takes x-rays and asks the patient to point out the spot on the spine where pain seems most severe. After identifying the most likely sites of inflammation, the doctor instructs the patient to lie on his or her stomach under the fluoroscope machine. The spine is sterilized and marked, and the machine is turned on to guide the placement of the needle.

Most specialists use a localized anesthetic solution during a facet block, but a steroid solution may be used for its therapeutic effects. After injecting the solution, the doctor asks if the patient experiences pain relief. If so, it is clear which facet is damaged. If no change is reported, the doctor can repeat the facet block on another nearby vertebral joint. Even if multiple injections are needed, the entire procedure can usually be performed in less than an hour.

After a facet block, the patient usually needs to stay at the surgical center for about an hour so the specialist can continue to monitor changes in symptoms. Once the anesthetic wears off, the patient is typically given a pain medication prescription and instructed to avoid physical activity for about two days. Ongoing treatment plans are usually made within a few days based on facet block results, which may involve arthritis medications, physical therapy, surgery, or all three.