Thoracic Medial branch blocks:
What are the medial branch nerves and why are medial branch blocks helpful?
Medial branch nerves are the very small nerves that allow one to feel pain from the facet joints. These nerves do not control any muscles or sensation in your arms or legs. They are located along a bony groove in your low back, neck and over a bone in your mid-back.
We have strong evidence to suspect that your facet joints are the source of your pain*. Unfortunately, simple joint injections and/or other treatments have not provided you with adequate pain relief. Therefore, you may benefit from having the small medial branch nerves and their pain signals interrupted via a controlled non-surgical heat lesion produced by a special needle. Before interrupting these nerves and their pain signals we first block the medial branch nerve signals with numbing medicine as a test. This tells us whether or not you are likely to benefit from having the medial branch nerves interrupted at a later date by the special radio-frequency (RF) needle. This more permanent treatment is called RF medial branch neurotomy.
What will happen to me during the procedure?
First, an IV will be started so that relaxation medication can be given if you so desire. After lying on an x-ray table, the skin over the area to be tested will be well cleansed. Next, the physician will numb a small area of skin with numbing medicine (anesthetic) which stings for a few seconds. Next, the physician will use x-ray guidance to direct a very small needle over the medial branch nerves. He will then inject several drops of contrast dye to confirm that the medication will only go over these medial branch nerves. A small mixture of numbing medicine (anesthetic) will then be slowly injected.
What should I do and expect after the procedure?
20-30 minutes after the procedure you will move the affected area to try to provoke your usual pain. You will report your remaining pain (if any) and also record the relief you experience over the next 6 hours on a pain diary we will provide. You may or may not feel improvement in the first few hours after the injection depending upon if the medial branch nerves that were injected are carrying pain signals from your spinal joints to your brain.
On occasion, your neck/back may feel numb or odd for a few hours after the injection. You may notice a slight increase in your pain lasting for several days as the numbing medication wears off. Ice will typically be more helpful than heat in the first several days after the injection. Although the main purpose of this procedure is as a test to see whether you would benefit from a subsequent medial branch neurotomy, on occasion long term relief can occur from injecting medication over these nerves. You may take your regular medications after the procedure, but try to limit your pain medications for the first 2 hours after the procedure so that the diagnostic information obtained is accurate.
On the day of the injection you should not drive and should avoid any strenuous activities. On the day after the procedure, you may return to your regular activities. If your pain is improved from this procedure, start your regular exercise/activities in moderation. Even if you are significantly improved, gradually increase your activities over 1-2 weeks to avoid recurrence of your pain.