Lumbar Sympathetic Block

What is a Lumbar Sympathetic Block?     

Lumbar Sympathetic Block is an injection of local anesthetic in the “sympathetic nerve tissue” – the nerves which are a part of Sympatheic Nervous System.  The nerves are located in the back, on either side of the spine.

What is the purpose of it?    

A block is performed to determine if there is damage to the sympathetic nerve chain and if the damage is the source of pain.  Primarily, this is a diagnostic test, but it may provide relief far in excess of the duration of an anesthetic.

The injection blocks the Sympathetic Nerves.  This may, in turn, reduce pain, swelling, color and sweating changes in the lower extremities and may improve mobility.  It is the treatment for Reflex Sympathetic Dystrophy Syndrome (RSDS), Sympathetic Maintained Pain, Complex Regional Pain Syndrome (CRPS) and Herpes Zoster (shingles) involving the lower extremities.

How long does the injection take?

The actual injection takes only a few minutes.

What is actually injected?

The injection consists of a local anesthetic (similar to lidocaine or bupivacaine); Epinephrine (adrenaline) or Clonidine may be added to prolong the effects of the injection.

Will the injection hurt?
The procedure involves inserting a needle through skin and deeper tissues (similar to a tetanus shot); there will be some discomfort involved.  However, the skin and deeper tissues can be numbed with a local anesthetic using a very thin needle before inserting the larger needle for the block.  Most patients also receive intravenous sedation and analgesia, making the procedure easier to tolerate.

Will I be “put out” for this procedure?

No. This procedure is done under local anesthesia.  Most patients also receive intravenous sedation and analgesia, making the procedure easier to tolerate.  The amount of sedation given generally depends upon the patient’s pain tolerance.

How is the injection performed?

The injection is performed with the patient lying on their stomach and the skin on the back is cleansed with an aniseptic solution.  Fluoroscopy (X-ray) is used to guide the needle(s) into the proper position and then the injection is performed. The patient will also be monitored with EKG, a blood pressure cuff, a blood oxygen monitoring device and temperature sensing probes placed on the feet.

What should I expect after the injection?  
Immediately after the injection, the patient may feel their lower extremities warming and the pain lessening or gone.  Some weakness and/or numbness may also be felt, but is temporary.

What should I do after the procedure?

The patient should have someone drive them home. The patient should perform as little as possible for at least a day or two after the procedure; or as tolerated based on the individual.  Some patients immediately follow the procedure with physical therapy.

How long will the effect of the medication last?

The local anesthitic wears off in a few hours.  However, the blockade of sympathetic nerves may last for many more hours.  Usually, the duration of relief gets longer after each injection.

How many injections do I need to have?

If you respond to the first injection, you will be recommended for repeat injections.  Usually, a series of such injections is needed to treat the problem.  Some may need only 2 to 4 and some may need more than 10.  The response to such injections varies from patient to patient.

Will the Lumbar Sympathetic Block help me?

It is very difficult to predict if the injection(s) will indeed help you or not.  The patients who present early during their illness tend to respond better than those who have this treatment after about six months of symptoms.  Patients in the advanced stages of disease may not respond adequately.

What are the risks and side effects?

This procedure is safe.  However, with any procedure there are risks, side effects, and possibility of complications.  The most common side effect is pain – which is temporary.  The other risks involve bleeding, infection, into blood vessesls and surrounding organs.  Fortunately, the serious side effects and complications are uncommon.

Who should not have this injection?

If you are allergic to any of the medications to be injected, if you are on blood thinning medications (e.g. Coumadin®, Plavix®, Ticlid®), or if you have an active infection going on near the injection site, you should not have the injection.

Information courtesy of Redding Anesthesia Associates Medical Group

ILLUSTRATION OF LUMBAR SYMPATHETIC BLOCK  From the Spine Health websitelumbar sympathetic block typically involves a series of injections to relieve leg pain (sciatica) caused by complex regional pain syndromes, usually after injury to a joint or limb. This video provides a full overview of lumbar sympathetic block injections.


1) Nerve Blocks are still the best Early Interventional Treatment for dealing with CRPS/RSD. They key is doing them early on in the disease, as quickly after onset as possible. Can there be problems with Nerve Blocks? Do they always work?

2) Why do nerve blocks work sometimes in the beginning of the disease and then they don’t seem to help later? Or maybe your first one helped a little but then the second one didn’t? Why is it important that a patient have the nerve blocks early on in the disease? Does that lead to a higher rate of remission? READ THIS ARTICLE THAT ATTEMPTS TO ANSWER THOSE QUESTIONS.

3) It may be suggested that you use ice in case of swelling near the block site. This is a tricky thing. We have always been told, “If it’s CRPS don’t ICE!” , yet like every other patient we are told in many situations that we need to use ice. It is the best way to reduce swelling. There is an article called Ice and CRPS that you can read that describes this unique relationship. It also explains the R.I.C.E and P.R.I.C.E. method for dealing with injuries.

4) It is very important to the success of your Nerve Block that you plan on several days of REST after your nerve block. Don’t plan on going back to work that day or the next, no big parties or walking adventures, nothing that involves stress or physical activity. The more you can let your body rest after a Nerve Block the better. Your body needs time to recover and the medication needs time to start working.

5) How long before I see results from the nerve block? Immediately after the injection many patients feel an increase in warmth. As far as a decrease in pain? That can take days or even a week or more for the medication to work on your body and for the chain of events to get set into motion. Give it time. Don’t get upset if you don’t suddenly feel you are able to get up and go dancing two days after your first nerve block.