Medial Branch Blocks
The bones of the spine are connected by facet joints. Each facet joint is no larger than a thumbnail and has two medial nerves, located in bony grooves in the spine, which carry the sensation of pain to your brain. If these nerves are causing pain, they can be treated by a procedure known as medial branch block in which the nerves are visualized by fluoroscopy and numbed by placement of local anesthetic. The procedure does not target the actual nerve root. A medial branch block is often used in an attempt to delay or avoid surgery. A positive diagnostic medial branch block will give the patient at least 50% pain relief for the duration of the local anesthetic. If the diagnostic injection is positive, it can be repeated to confirm the results and/or followed by a procedure known as radiofrequency ablation denervating the nerves to obtain longer-lasting pain relief. A medial branch block can also be performed for therapeutic purposes, and in that case, a corticosteroid is injected along with the local anesthetic in an attempt to provide additional longer-lasting pain relief.