A facet joint block is a procedure that is used to determine if a facet joint is the source of a patient’s persistent pain. The facet joints that are involved are most often in the neck or the lumbar area of the back. This type of nerve block can be effective both as a diagnostic tool and a treatment.
Facet joints are small joints between your vertebrae. They are paired joints, which means that there is a left facet joint and a right facet joint between every two vertebrae of the spine. Each joint is separated by pads of cartilage that allow it to twist and bend forward, backward and sideways, giving your spine its impressive flexibility.
The facet joints are supplied with a number of small nerves that can transmit pain information to your brain. This pain is usually due to inflammation in the joint that results from an injury or a degenerative process like arthritis. A problem in the lumbar region of your back is usually felt as pain in the immediate area of the joint. If the inflammation is in the neck joints, you may have pain, headaches, or muscle spasms.
Facet Block Purpose
The primary purpose of a facet block is to determine the cause of the pain you are experiencing. If the block relieves the pain, your doctor knows that inflammation or degeneration in the joint is the problem. If your pain continues, the doctor knows that something else is causing it. Because the block is an invasive procedure, you will usually have it only after MRI or CAT scans have failed to identify the source of your pain. The fact that the block provides direct pain relief is a secondary benefit, and it may or may not be the best therapy for you over the long term.
Facet Block Procedure
The block procedure is performed by either an anesthesiologist or a radiologist. It is an outpatient procedure and you will go home the same day. It is common for patients to be lightly sedated to allow them to relax during the block.
You will be lying face down on a table for the procedure, and a local anesthetic will be administered to the injection site. The doctor will insert a long, thin needle into your back or neck, positioning it into the facet joint. A type of real-time X-ray called fluoroscopy will be used to allow the doctor to see exactly where the needle is, so it can be precisely placed.
Once the needle is properly positioned, a combination of anesthetic and cortisone is injected into the joint. The anesthetic stops the nerves from transmitting pain signals. The cortisone helps reduce the inflammation that is putting pressure on the nerves. The entire injection process takes about 15 minutes.
While you may have several painful facet joints, you will usually not have more than three treated at one time. There are a couple of reasons for this. It has been found that treating more than three joints does not seem to provide a proportionally greater relief of pain. It is also the case that some patients react badly to too many injections, so the risk is high and the benefits are low.
After your procedure, you will be observed closely for about 15 minutes. This lets the doctor make sure you are not having an adverse reaction and gives you the chance to assess how much, if any, your pain has lessened. After a brief recovery period, you will be allowed to go home and resume most normal activities.
Duration of Pain Relief
The pain relief that you experience immediately after the facet block is due to the anesthesia that was injected. This effect will wear off in a few hours. The cortisone steroid that was also injected will provide longer-term relief as it reduces the swelling in the joint. It may be from two to seven days before you begin to feel this effect, and it may last for several weeks or months.
If you respond well to the facet block, you can repeat the procedure up to three times per year. However, the block is often just used for the initial diagnosis, and more permanent treatments are often recommended as the next step.