A lumbar sympathetic block typically involves a series of injections to relieve low back pain or leg pain (sciatica) caused by complex regional pain syndromes, usually after injury to a joint or limb. It involves an injection of local anesthetic into or around the sympathetic nerves, which are a series of nerves that spread out from the spine to help control involuntary body functions. The nerves are located on either side of the spine, in the low back. A lumbar sympathetic block is used to reduce pain, swelling, color, sweating and other unusual changes in the leg, and improve mobility. It is used to treat Reflex Sympathetic Dystrophy (RSD), Sympathetic Maintained Pain, Complex Regional Pain Syndrome, Herpes Zoster (shingles) involving the leg, cancer pain and certain patients with neuropathy or peripheral vascular disease.
The injection takes from ten to thirty minutes and consists of a local anesthetic. On occasion, epinephrine, clonidine or a steroid medication may be added to prolong the effects of the lumbar sympathetic block.
Sympathetic blocks don’t work for everyone and the pain relief that they provide may lessen over time. For some, a sympathetic block may provide weeks or months of pain relief, and permanent relief is possible.