Facet joint injections or facet blocks are commonly used to determine what is causing back pain. Facet block injections are primarily diagnostic injections, meaning that they help your doctor determine the cause of your back pain but may not provide you with any long-term relief from the pain.

Injections eliminate pain temporarily by filling the facet joint with an anesthetic medication that numbs the facet joint, the ligaments, and the joint capsule around the facet joint. If the facet joint is injected and your pain goes away for several hours, then it is very likely that the joint is causing your pain. Once you and your doctor know what structure is causing your pain, you can begin to explore options for treating the condition.

For the most accurate and safest injection placement of facet joint injections, it is best to use fluoroscopy (live X-ray) for needle placement guidance to prevent nerve injury.

Dr. Ningning is the top board-certified pain management specialist in New Jersey who performs facet joint injections for facet syndrome.

Anatomy of Facet Joint

Between the vertebrae of each spinal segment are two facet joints. The facet joints are located on the back of the spinal column in the lumbar and thoracic spine. In the neck or cervical spine, they are located on each side of the vertebra.

There are two facet joints between each pair of vertebrae, one on each side of the spine. A facet joint is made of small, bony knobs that line up along the back of the spine. Where these knobs meet, they form a joint that connects the two vertebrae. The alignment of the facet joints of the spine allows freedom of movement as you bend forward and back.

The surfaces of the facet joints are covered by articular cartilage. Articular cartilage is a smooth, rubbery material that covers the ends of most joints. It allows the bone ends to move against each other smoothly without friction. Each joint is surrounded by a joint capsule. The joint capsule is made up of the ligaments and connective tissues that help hold the joint together. The joint capsule forms a water-tight sac that contains the joint fluid.

During a facet block injection, the tip of the small needle is placed inside the joint, and the joint is filled with medications to anesthetize (or numb) the joint and reduce the inflammation in the joint.

Facet Block Injection for Low Back Pain

Recommendation – Facet joint injection to try and determine if the joints are the cause of your back pain. This type of injection is primarily a diagnostic injection. The injection may only help your pain temporarily, sometimes just for a few hours. Once your doctor is sure that it is the facet joint causing your pain, other procedures may be recommended to reduce your pain for a longer period of time.

During a facet joint block injection, the medications that are normally injected include an anesthetic and cortisone. The anesthetic medication (such as novocaine, lidocaine, or bupivacaine) is the same medication used to numb an area when you are having dental work or having a laceration sutured. The medication causes temporary numbness lasting one hour to six hours, depending on which type of anesthetic is used.

Cortisone is an extremely powerful anti-inflammatory medication. When this medication is injected into a painful, inflamed joint, it can reduce inflammation and swelling. Reducing the inflammation reduces pain. If cortisone is also injected into the joint at the same time, you may get several weeks’ worth of relief from your pain. This can allow you to get started in a physical therapy program, strengthen the muscles, and begin normal movement again. When the cortisone wears off, the pain may not return.

Facet Joint Injection Procedure

When you are ready to have the injection, you will be taken into the procedure area and an IV will be started. The IV allows your doctor to give you any medications that may be needed during the procedure. The IV is for your safety because it allows a very rapid response if you have a problem during the procedure, such as an allergic reaction to any of the medications injected. If you are in pain or anxious, you may also be given medications through the IV for sedation during the procedure.

Facet joint injections are done with the help of fluoroscopic guidance. A fluoroscope is an X-ray machine that allows the doctor to actually see an X-ray image while doing the procedure. This allows the doctor to watch where the needle goes as it is inserted. This makes the injection much safer and much more accurate. Once the needle is in the right location, a small amount of radiographic dye is injected. This liquid dye shows up on the x-ray image, and the doctor can watch where it goes. The anesthetic medication and the cortisone will go in the same place. The doctor wants to make sure the injection will put the medication where it can do the most good. Once the correct position is confirmed, the anesthetic and cortisone are injected, and the needle is removed.

What to Expect Immediately After

You will be asked to rest in the recovery area for about 20 or 30 minutes following the facet joint injection. It’s likely that the medical team at this point will ask you to perform some simple movements. These may be movements to check whether you have experienced immediate pain relief. By moving, you will ensure that you are recovering from the injection and that it is safe for you to leave.

We will answer any questions you may have and address any concerns before you leave. It is possible to experience some numbness in your neck or back for a few hours following the injection, although this is not always the case. You may feel an odd sensation instead of numbness, or these areas may feel weak and achy. Part of the reason why you shouldn’t drive after a facet joint injection is because of this.

Facet Joint Injection Pain Relief Results

Usually, the patient will feel immediate pain relief after the local anesthetic and will start to notice longer-lasting pain relief two to five days after the steroid injection if the treated facet joints are the source of the pain.

Further diagnostic testing (medial branch nerve injection) or treatment (radiofrequency neurotomy) may be performed if the numbing medication fails to provide immediate relief but the steroid does not provide any lasting improvement.

Nonetheless, if the patient’s pain does not improve after taking the numbing medication, further testing may be required to accurately diagnose the problem.

Pain diary pages should be filled out during the first several hours and for the next several days to capture the patient’s experience of pain relief. When treating physicians need to plan future tests and/or treatment, a pain diary helps them understand the injection results.

Usually, the facet block procedure can be performed up to three times a year if it is effective at relieving the patient’s back pain. The patient must not undergo a second injection if the first injection fails to relieve the pain.