Sympathetic Nerve Block

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.

What Are the Sympathetic Nerves?

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.