What is a facet joint?

The facet joints link the vertebrae together and give them the flexibility to move against each other. There are two facet joints between each pair of vertebrae, one on each side. They extend and overlap each other to form a joint between the neighboring vertebra facet joint. The facet joints enable bending and twisting movements of the spine.

What is a medial branch nerve?

The medial branch is the branch of the spinal nerve that carries sensation and pain signals from the facet joint back to the spinal cord.

How do the facet joints cause pain?

The facet joints are just like any other joint in the body, they are susceptible to acute injury (sprain or strain) as well as degenerative arthritis. In the back, the facet joints may cause low back pain, hip and buttock pain, and leg pain. The pain is especially bad when leaning backwards or twisting your spine. The pain also tends to be worst first thing in the morning and in the evening.

What are the indications for a facet joint injection or medial branch block?

These injections are performed as a diagnostic test when it is thought that a facet joint or joints is part of the process that is causing the pain. A small amount of a local anesthetic is injected into the joint or over the medial branch nerve to see if this will temporarily relieve your back pain.

How long will the pain relief last after a facet joint injection or medial branch block?

The local anesthetic block will only last a few hours. A small amount of steroid may be injected along with the local anesthetic and may provide pain relief from days to months.

Can a facet joint injection make my pain worse?

Some patients will experience mild pain with the procedure that will ease up in a very short amount of time. On rare occasions, patients have experienced a prolonged increase in pain after the procedure.

What if a facet joint injection does not improve my pain?

Facet joint injections or medial branch blocks are performed to diagnose pain being caused by the facet joints in your back and will not relieve pain caused by intervertebral discs, spinal nerves, or muscles, which can continue to cause pain after the procedure. If your pain is not relieved after the procedure, the facet joints have been ruled out as the source of your pain.

What if the facet joint injection is successful?

If the facet joint injection successfully treat your pain for a significant period of time, they may be repeated as necessary. If the facet joint injection relieves your pain for a short period of time, then you will likely be scheduled for radiofrequency ablation (RFA) of the medial branch nerves.

Are there any restrictions following the facet joint injection?

We ask that you not immerse in water for 24 hours after the injections. This means that you can shower, but not take a bath or go swimming for the rest of the day. There are no other specific restrictions on activity however, we recommend that you “take it easy” the rest of the day and slowly resume your normal activities.

What are the risks of the facet joint injection?

Overall, facet joint injections (and medial branch blocks) are a very safe procedure. Serious side effects or complications are rare, however, like all injection procedures, possible adverse effects are possible. The most common complications include bleeding and bruising at the needle puncture site, post-procedure headaches, and lightheadedness or dizziness immediately following the procedure. Other very rare complications include transient numbness or weakness, paralysis (partial or complete), contrast or allergic reactions, sexual dysfunction, and death. If you experience any concerning symptoms after your injection, you should call your doctor immediately or go to an emergency room for evaluation.

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