A sympathetic nerve block involves injecting numbing medicine around the sympathetic nerves in the low back or neck. By doing this, the sympathetic nervous system in that area is temporarily ‘switched’ off in hopes of reducing or eliminating pain. If pain is substantially improved after the block, then a diagnosis of sympathetically mediated pain is established. The therapeutic effects of the anesthetic can occur, at times, longer than would be normally expected. The goal is to reset the sympathetic tone to a normal state of regulation. If the initial block is successful, then additional blocks may be repeated if the pain continues to sequentially diminish. You may also have redness of the lower extremity and a feeling of warmth.
A local anesthetic is given in the lumbar area of the back. A needle is then inserted into the back under the fluoroscopy next to the vertebral body. The block may be performed on both sides the spine. An anesthetic medication will be injected into the area. It takes 30 minutes for the procedure followed by a recovery period.