Sometimes it feels like muscle tension. A medial branch block is an injection of a strong local anesthetic on the medial branch nerves that supply the facet joints. Cervical Plexus Block - Landmarks And Nerve Stimulator Technique - Nysora If a branch block does not work, there is another issue causing back pain. What if cervical medial branch block doesn't work . This means the medial branch block may be 100% ineffective at stopping pain, which means a patient must pay for a procedure that wound up being completely useless. The term back pain includes pain affecting the neck, midback and low back. The medial branch nerve block is designed to interrupt the pain signal being carried by the medial branch nerves supplying a specific facet joint. If pain is relieved, it could mean the facet joint that is generating the pain has been identified. While the procedure may take less than 15 minutes, you should allow for at least one hour at the procedure center. Acute back pain ...