Patients dealing with persistent neck or back pain may be offered a number of treatments by their doctors. A pain medicine doctor is likely to recommend a medial branch nerve block (MBNB) after conventional treatments have been tried and failed.
MBNB is an interventional treatment. But unlike other interventional treatments designed for long-term relief, MBNB is more for diagnostic purposes. Understanding how an MBNB works – and what the results might mean – is key to figuring out whether it is right for you.
What It Is and How It Works
The first step in figuring it out is understanding what it is and how it works. For starters, your spine is made up of a series of vertebrae with stabilizing joints between each one. These joints are called facet joints. They are no different from any other joints in the human body, which is to say that they can develop arthritis. They can suffer from wear and tear, injury, disease, etc.
Also note that each joint is supplied by sensory nerves known as medial branch nerves. They carry pain signals straight to the brain.
The MBNB gets its name from the fact that the procedure blocks pain signals so that they never reach their destination. It is a precise, image-guided injection procedure that relies on a small amount of local anesthetic to temporarily relieve pain. The amount of pain relief a patient experiences determines what happens next.
What’s Next Depends on Your Body’s Response
The experts at Lone Star Pain Medicine in Weatherford, TX, make it clear that MBNB is not a permanent solution to back pain. Because the injection is just a local anesthetic, pain relief tends to wear off after several hours. So then what is the point?
As previously stated, MBNB is a diagnostic tool. It helps doctors and patients figure out where to go based on the results of the procedure. Doctors typically ask patients to keep a detailed pain diary for four to six hours following MBNB. They are expecting one of three outcomes:
1. Significant Pain Relief (80% or Greater)
Significant pain relief suggests the doctor’s initial diagnosis is correct. The pain is being caused by an issue with one of the facet joints. In most cases, the next step is radiofrequency ablation (RFA), also known as radiofrequency neurotomy. Our RFA relies on radio waves to create a lesion on the targeted nerve. As long as the lesion remains, pain signals are blocked.
2. Partial Pain Relief (30% to 70%)
Partial pain relief suggests a combination of sources. For example, you might have arthritis in one of your facet joints along with disc degeneration and muscle tightness. The next step would be further evaluation to determine what the best kind of treatment is. Treatments for combined problems include things like trigger point injections and targeted epidurals.
3. Little to No Pain Relief (Less Than 30%)
Little to no pain relief suggests that the doctor’s initial diagnosis is wrong. Unfortunately, you are back to square one. You and your doctor will have to explore other possible causes of your back pain.
As a diagnostic tool, MBNB helps doctors fully understand what is causing back pain. When the test is successful, other treatments can address the patient’s problem. The one thing that must be understood is that MBNB is not considered a long-term treatment.
If you are experiencing back pain that you think might be related to your facet joints, ask your doctor about MBNB. You might even be able to get a referral to a pain medicine clinic like Lone Star.