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Sympathetic Nerve Block

Woman holding forearm, looking distressed.

A sympathetic nerve block helps your doctor find the cause of the burning, pain, or tingling in your arms and hands or legs and feet. During the test, medication is injected near your spine. This “blocks” the sympathetic nerves in that region. If these nerves are causing your problem, the injection will relieve your symptoms for a while. Be aware that this procedure may not work if your pain is not caused by these nerves.

What Are the Sympathetic Nerves?

Outline of back view of man showing major sympathetic nerves in back, arms, and legs. Stellate ganglion is in upper back near neck. Sympathetic chains run down back on either side of spine.

The sympathetic nervous system is a network of nerves throughout your body. The nerves branch from your spine. They control some body functions, such as the closing of blood vessels. A problem with these nerves can affect blood flow. Symptoms are often felt in the hands or feet. They may hurt, burn, feel cold, or be tender to the touch.

Sympathetic Ganglions

The sympathetic nervous system is controlled by bunches of nerves called ganglions. One large ganglion, called the stellate ganglion, helps control nerves in the upper body. In the lower body, nerves are controlled by several ganglions that make up the sympathetic chain.

Risks and Complications

Risks and complications are rare, but can include:

  • Bleeding or fluid leakage in the spinal cord

  • Puncture of a blood vessel

  • Infection

  • Lung puncture (pneumothorax)

Author: StayWell Custom Communications
Last Annual Review Date: 5/15/2011
Copyright © The StayWell Company, LLC. except where otherwise noted.
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