The spine’s joints are called facet joints or zygapophyseal joints. Facet joints are found in the cervical (neck), thoracic (mid back), and lumbar (low back) spine. These joints allow the spine to flex, extend, and rotate. The medial branch nerve innervates (stimulates) the facet joint. As we age, or secondary to trauma (such as whiplash), the facet joints can be damaged and develop arthritis similar to other body joints.
Facet joint pain can be secondary to back pain and may radiate (travel) into the hips, buttocks, and posterior thighs. While arthritis is commonly detected by x-ray or MRI, the presence of arthritis/facet hypertrophy (increased joint size) does not always mean it is the cause of low back pain.
The medial branch nerve innervates the facet joint and may cause nerve root irritation and pain. A medial branch nerve root block is performed to confirm that a facet joint is the source of your pain. While the nerve block is diagnostic, it may be therapeutic providing pain relief.
Before the nerve block, you may be given medication to relax you (optional). Most patients do not need anesthesia (twilight) because the needles are very small (25 or 27 gauge).
The skin area is numbed using a local anesthetic. Using fluoroscopy (real-time x-ray), the physician guides the needle into the proper area of your spine. Once the needle is positioned near the median nerve, a combination of anesthetics (less than half of 1 cc) is injected into the medial region. The entire facet block procedure takes less than 10 minutes.
If you are interested in an evaluation into the cause of your low back pain, or a facet medial nerve block to manage your pain, please contact our pain management experts at The Spine and Pain Institute of New York in Manhattan, New York and Staten Island, New York. We would be happy to make an appointment for a consultation and provide additional information about other treatment options.