Medial Branch Blocks

Each facet joint in the spine sends pain signals through tiny nerves called medial branch nerves. A medial branch block places a small amount of numbing medicine next to these nerves to briefly turn off the pain signals from specific facet joints.

It is mainly a test. If your usual back or neck pain improves a lot for several hours after the block, the facet joints are very likely the source, and you may be a good candidate for radiofrequency ablation, which can give much longer relief. Many insurance plans require one or two successful blocks before ablation.

These injections are usually performed by a pain management specialist or interventional physician. Dr. Grunch works closely with trusted pain management specialists and will refer you when an injection is a good next step, either to treat your pain or to help confirm where it is coming from.

• Chronic back or neck pain thought to come from the facet joints
• People with spinal arthritis whose pain is worse when leaning back or twisting
• Patients being considered for radiofrequency ablation

• Ask about blood thinners. If you take a blood thinner such as warfarin, apixaban (Eliquis), rivaroxaban (Xarelto), clopidogrel (Plavix) or daily aspirin, tell the doctor doing the injection. Some injections require stopping it for a few days and some do not. Never stop a blood thinner on your own; the doctor who prescribes it will tell you if and when it is safe.
• If you have diabetes and a steroid will be used, check your blood sugar more often for a few days afterward.
• Tell the team about any allergies, especially to contrast dye, iodine, latex or numbing medicine.
• Reschedule if you have a fever or an infection, or if you might be pregnant.
• Arrange for a driver if you will be given medicine to relax.
• Come with your usual pain and avoid extra pain medicine that morning unless instructed, so the block can show whether it relieves your pain.

You will lie on a table, usually face down. The skin is cleaned and numbed. Using live X-ray (fluoroscopy) or sometimes ultrasound, the doctor guides a thin needle to the exact spot. A small amount of contrast dye is often used to confirm the needle position before the numbing medicine is injected. You may feel pressure or a brief, familiar pain. The injection itself usually takes 10 to 30 minutes.

This part matters most. For the next 6 to 8 hours, do the activities that usually cause your pain and record how much better it is in the pain diary you are given. Relief from the numbing medicine fades as the day goes on, which is expected. If your pain improved substantially, the next step is often radiofrequency ablation.

Medial branch blocks are low-risk. Possible side effects include temporary soreness, numbness and, rarely, infection or bleeding.

Why is the relief from a medial branch block temporary?

The block uses only numbing medicine, so it wears off in hours. Its purpose is to show whether the facet joints cause your pain. If they do, radiofrequency ablation can give longer relief.

Why do I need two blocks?

Two separate blocks with good relief make it more certain that the facet joints are the source, and many insurance plans require them before ablation.

What should I do after a medial branch block?

Try the activities that normally hurt and write down how much better your pain is over the next several hours.

If you have neck pain, back pain or nerve pain and want to know which treatments make sense for you, call 470-293-9800 or contact us to schedule a visit with Dr. Grunch or one of her physician assistants. You can also ask general questions any time through our “Ask Us Anything” chat.

Related: All non-surgical treatment options · Radiofrequency ablation · Facet joint disease

This information is for educational purposes only and is not medical advice. It does not replace individualized care from a licensed physician. Please talk to your provider about your symptoms and treatment options.