Anchorage: (907) 278-2741

Fax: (907) 743-8284

Anchorage: (907) 278-2741

Fax: (907) 743-8284

Lumbar Medial Branch Block

Treatment for Pain in

Lower Back, Buttock, and Groin


Facet joints are used to connect the vertebrae and they help guide your spine as you move. They are found on both sides of the spine and are named for the vertebrae they connect and the side of the spine in which they are found. For example, the left L4-5 facet joins the fourth and fifth lumbar vertebrae on the left side of the spine.

Medial branch nerves are found near facet joints and transmit pain signals from the facet joints to the brain. Lumbar facet joint pain can range from simple muscle tension to severe pain, and is dependent upon the injury and the joint which is affected. The injury can include the cartilage inside the joint itself or just the connecting ligaments surrounding the joint, with pain occurring from your lower back down to your buttocks.


In a lumbar medial branch block, an anesthetic is injected near the medial branch nerve. This stops the transmission of pain signals from the facet joint. If this relieves or reduces your pain and allows you to move your back normally, it tells the physician which facet joint is causing your pain.

The procedure may start with an IV to help you relax and a local anesthetic to numb your skin. The physician then inserts a very thin needle near the facet joint. Fluoroscopy, a type of X-ray, is used to ensure proper needle placement and a dye may also be injected to make sure the needle is in the correct spot. Once the needle is correctly placed, the physician injects the anesthetic.

You will be monitored following the injection, at which time you will be given your discharge instructions and be allowed to leave the clinic. You may notice immediate relief and numbness in your back for a few hours after the injection, which means the medication has reached the correct spot.

Relief varies from person to person and depends on the amount of inflammation involved, as well as the number of injured areas. If your pain subsides for a short time only to return, you may be a good candidate for radiofrequency ablation (RFA) to the medial branch nerve, which can provide a more permanent disruption of pain signals.

Get In Touch With Us!

Whether you are suffering from a recent injury or chronic back pain, we are here to provide the best medical care possible to get you back to doing the things you enjoy.