What Are Lumbar Sympathetic Blocks?

Lumbar sympathetic blocks explained by Denver, Golden, Aurora, Boulder, Broomfield, Jefferson, and Littleton Colorado’s top pain doctors

Drawing - Lumbar Sympathetic BlockA lumbar sympathetic block is an injection that is administered to patients in order to reduce pain that is caused by lumbar nerves. A sympathetic chain is an essential nerve bundle that is the length of the spine and runs parallel to the spinal cord. The roots of the nerves are located in the spine, and they extend to various regions of the body in order to regulate important biological functions. A bundle or a cluster is also referred to as a ganglion and this structure is comprised of numerous nerve endings. The clusters form a chain that runs from the upper region of the body to the lower region, which controls movement, sensations, and blood flow to the lower extremities.

If the clusters become irritated or damaged, processes such as the control of blood pressure and sensation in the pelvis, legs, and feet become disrupted and pain may develop. Oral pain relievers are usually ineffective for this type of pain. Injecting pain-relievers directly into the region where affected nerve clusters are located is typically quite effective at reducing pain. This type of injection usually entails administering an analgesic into the lumbar sympathetic chain that contains the irritated cluster in order to block the transmission of pain sensations to the brain. As a result, a lumbar sympathetic block can effectively improve the symptoms of chronic conditions. This procedure is especially useful for patients who have leg or pelvic pain that did not improve after taking oral medication, but did experience relief after undergoing a lumbar sympathetic block.

How is a Lumbar Sympathetic Block Performed?

LidocaineA local anesthetic is applied to the injection site before the procedure begins. Next, the region that contains the affected nerves is located with the use of imaging techniques (e.g. an MRI or fluoroscopy) in order to ensure that the needle will be correctly inserted and positioned. Lidocaine is one of the most common anesthetics that is injected into the cluster along with a corticosteroid. The corticosteroid decreases inflammation, while the anesthetic relieves pain.

A lumbar sympathetic block is also used quite often to diagnose the pain source. This is especially useful when the injection is administered for neck or back pain that may be the result of inflamed sympathetic nerves. Furthermore, it does not require surgery, making this a minimally invasive approach that provides a significant improvement in symptoms from chronic pain. In doing so, a lumbar sympathetic block allows patients to quickly regain their quality of life, especially when oral medication is ineffective.

There are a few risks that are associated with this procedure, including drug interactions, infection, bleeding, and nerve damage. In addition, the steroids that are administered may increase the risk of developing osteoporosis or arthritis. Steroids may also lead to weight gain and weaken the immune system. The anesthetic that is injected can inadvertently decrease nerve function as well. There have also been rare cases in which patients have had severe adverse reactions to the anesthetic such as respiratory problems and chest pain. These types of neurological deficits typically do not require treatment and are generally short term.

A lumbar sympathetic block can also cause priapism in rare cases, which is characterized as blood that involuntarily rushes to the pelvic region. This side effect is especially problematic in men. Drooping eyelids, feeling as if the nose is blocked, and a headache may also develop after receiving a lumbar sympathetic block.

Conditions Related to Lumbar Sympathetic Blocks

Lumbar Sympathetic Block DiagramA lumbar sympathetic block is generally recommended for back pain and leg pain that develops due to inflamed lumbar nerve bundles. This type of block is also an effective treatment option for cancer patients who experience pain in the pelvis and legs or those who are suffering from cancer treatment-related pain. Complex regional pain syndrome is another condition that causes pain in the legs and patients who undergo a lumbar sympathetic block typically experience rapid pain relief. However, the exact cause of the chronic pain that this syndrome causes is often hard to diagnose. In such cases, a lumbar sympathetic block can be used as a diagnostic technique in order to identify the sympathetic cluster that is the source of the pain.


A lumbar sympathetic chain is a nerve bundle that regulates various biological functions such as pain transmission and vital signs. If these nerve bundles become damaged, they can result in irritation and pain in the back and legs. A lumbar sympathetic block is an injection that delivers medication directly into the affected nerve cluster and this technique has been successfully used to treat numerous conditions. There are certain risks associated with sympathetic blocks such as drug interactions, nerve damage, and bleeding, but the occurrence is minimal. Therefore, this is an effective and safe treatment approach that helps patients avoid more invasive treatments (e.g. surgery).

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  1. Fritz J, Sequeiros RB, Carrino JA. Magnetic resonance imaging-guided spine injections. Topics in magnetic resonance imaging : TMRI. 2011;22(4):143-151.
  2. Gulati A, Khelemsky Y, Loh J, Puttanniah V, Malhotra V, Cubert K. The use of lumbar sympathetic blockade at L4 for management of malignancy-related bladder spasms. Pain physician. 2011;14(3):305-310.
  3. Krumova EK, Gussone C, Regeniter S, Westermann A, Zenz M, Maier C. Are sympathetic blocks useful for diagnostic purposes? Regional anesthesia and pain medicine. 2011;36(6):560-567.
  4. Bottger E, Diehlmann K. [Selected interventional methods for the treatment of chronic pain: Part 1: peripheral nerve block and sympathetic block]. Der Anaesthesist. 2011;60(5):479-491;quiz 492.
  5. Balthasar A, Desjardins AE, van der Voort M, et al. Optical detection of vascular penetration during nerve blocks: an in vivo human study. Regional anesthesia and pain medicine. 2012;37(1):3-7.
  6. Hong JH, Kim AR, Lee MY, Kim YC, Oh MJ. A prospective evaluation of psoas muscle and intravascular injection in lumbar sympathetic ganglion block. Anesthesia and analgesia. 2010;111(3):802-807.
  7. Rigaud J, Delavierre D, Sibert L, Labat JJ. [Sympathetic nerve block in the management of chronic pelvic and perineal pain]. Progres en urologie : journal de l’Association francaise d’urologie et de la Societe francaise d’urologie. 2010;20(12):1124-1131.
  8. Hong JH, Oh MJ. Comparison of Multilevel with Single Level Injection during Lumbar Sympathetic Ganglion Block: Efficacy of Sympatholysis and Incidence of Psoas Muscle Injection. The Korean journal of pain. 2010;23(2):131-136.
  9. Meier PM, Zurakowski D, Berde CB, Sethna NF. Lumbar sympathetic blockade in children with complex regional pain syndromes: a double blind placebo-controlled crossover trial. Anesthesiology. 2009;111(2):372-380.