A lumbar sympathetic block is performed to relieve leg pain caused by complex regional pain syndromes, which may develop after an injury to joint or limb. Complex regional pain syndromes transmit pain signals via the sympathetic chain. An injection of local anesthetic over the lumbar sympathetic chain can relieve this type of “sympathetic” pain in the leg. A series of injections may be needed to provide successful pain relief.
How Does it Work?
Complex regional pain syndromes transmit pain signals via the sympathetic chain. An injection of local anesthetic over the lumbar sympathetic chain can relieve this type of “sympathetic” pain in the leg. A pair of sympathetic chains lies along the front of the vertebra in the spine. The right sided chain receives sympathetic signals from the right side of the body and the left sided chain accounts for the left side of the body. The chains end at the L2 or L3 vertebra. If complex regional pain syndromes are in both legs, each sympathetic chain should be blocked to provide pain relief.
How Is It Done?
Using fluoroscopic guidance (X-ray), a needle is directed to the end of the sympathetic chain at the L2 or L3 vertebra in the low back. Moderate sedation and/or a local anesthetic may be used to ensure the patient’s comfort. A small amount of X-ray dye is injected to confirm proper placement of the needle. Then a local anesthetic is injected. The patient may feel warmness in the leg after the injection. The needle is removed and the patient is taken to the recovery room.
What Are The Risks?
As with any invasive procedure there are some risks and complications associated with a lumbar sympathetic block. Any time a needle is put into the body; there is a risk of infection or bleeding, or allergic reaction. The risk of infection is reduced by using sterile techniques. The risk of bleeding is very minimal if patients are not on any blood thinners. There are very few allergic reactions to the medications that are used for the injection. If any allergic reactions are identified, medications will be given and patients will be observed to prevent any serious complications. Lumbar sympathetic injections also pose a risk for a spinal headache, kidney puncture, and a drop of blood pressure. A spinal headache is a headache that gets worse with sitting up. It usually improves in 1-2 days with lying flat, drinking water and taking caffeine. Occasionally, a persistent spinal headache must be treated with a blood patch. Patients with a persistent spinal headache should contact the office.
What Can I Expect After?
Most patients feel immediate relief from a lumbar sympathetic block. Patients usually go home about 20-30 minutes after the injection. Patients are advised to rest on the day of the injection, but may return to normal activities the next day. Repeat injections may be needed to provide optimal pain relief. Patients will often be instructed to make a follow-up appointment after the injection.