Facet Joint Injections
Facet joints connect the vertebrae, and provide for the stability and flexibility of the spine. There are two facet joints between each pair of vertebrae, one on each side. Facet joints link each vertebra to those directly above and below it, and allow the vertebral bodies to rotate with respect to each other. Cartilage in the joints allows for smooth movement where vertebral bones meet, and each is lined with a thin membrane called the synovium, which produces synovial fluid for lubrication.
If the facet joints and the tissues around them become inflamed and swollen, these irritated structures can compress one or more spinal nerve roots. The result may be localized and/or radiating pain and other symptoms, such as numbness and muscle weakness.
A facet joint injection, or facet block, is a non-surgical procedure in which a combination anesthetic/steroid is delivered directly into a facet joint in the spine that may be causing back or neck pain. The purpose of the anesthetic is to ease the pain; the steroid to relieve inflammation. The effects of the injection may be temporary or permanent, and the procedure also may be used as a diagnostic tool to determine whether the facet joint is the cause of the pain.
There are a variety of spinal conditions that may cause pain and irritation of the facet joints.
- Facet joint syndrome
- Spinal stenosis
- Disc herniation
A facet injection is typically recommended for patients with radiating pain, and whose symptoms have not responded to other conservative therapies, such as medication, rest, exercise/activity modification, physical therapy or bracing.
During a facet joint injection, the anesthetic/steroid solution is delivered via a very thin needle, guided by fluoroscopy (a specialized X-ray camera), into the capsule that surrounds the facet joint or in the tissue around the joint capsule. This is different from an epidural spinal injection, in which the injection is placed in the epidural space of the spinal cord, located between the dura (the protective membrane that surrounds the spinal cord and nerves) and the bone of the vertebral canal.
Facet injections are typically performed on an outpatient basis and usually take about 10-15 minutes to complete. Only local anesthesia is required, and most patients are able to walk immediately after the procedure without using a recovery room or hospitalization. You’ll be monitored for a short period of time before you will be released, and you should have a responsible adult on hand to drive you to and from your procedure. You also should arrange to take it easy for at least 24-36 hours after the injection, to allow the anti-inflammatory medicine to take effect.