What Is Lumbar sympathetic block?

A lumbar sympathetic block is an injection of a local anesthetic that can help relieve chronic leg and foot pain caused by conditions such as complex regional pain syndrome, reflex sympathetic dystrophy, vascular insufficiency, and shingles. Medications are delivered to the sympathetic nerves – a cluster of nerve cell bodies – along the front side of the spine. The goal is to reduce pain so that you can resume normal activities and physical therapy.

The sympathetic nerves are part of the autonomic nervous system that controls our “fight-or-flight” response. They can constrict blood flow and increase heart rate, perspiration, and blood pressure.

Sometimes these nerves can transmit pain after an injury. A numbing agent (lidocaine or bupivacaine) is injected during this minimally invasive procedure. In some cases, a corticosteroid (betamethasone, triamcinolone, or dexamethasone) can also be injected.

The medications are delivered to the sympathetic ganglia adjacent to the L2, L3, and L4 vertebrae. The numbing agent can relieve pain, while the corticosteroid can reduce inflammation.

In many ways, this is akin to rebooting a frozen computer.  Once rebooted, the computer assumes its usual function.


Lumbar sympathetic block Overview

You will lie face down on the x-ray table. You may be given a low-dose sedative.

The doctor will insert a hollow needle under fluoroscopic guidance through the skin and direct it to the lumbar sympathetic ganglia . The fluoroscope allows the physician to watch the needle movement in real time on a monitor. Contrast dye is injected to assure proper placement. Some discomfort occurs, but patients typically feel a sensation of pressure more than pain.

There are two types of autonomic or in the body. The sympathetic and the parasympathetic. As the name implies bar sympathetic block local anesthetic that disrupts the sympathetic nerves.

The ganglia or the cell bodies for the sympathetic sit in the front of the lumbar spine at around the second and third lumbar vertebral levels.


the sympathetic nerves from the lumbar sympathetic plexus travel to the lower extremity leg thigh and feet. Therefore painful conditions in these areas can be treated.

Most common condition that is treated is complex regional pain syndrome, formerly called RSD.

This results trauma major or minor to the lower extremity which causes a hyperactivity of the sympathetic nerves pain burning pain to even light touch or a breeze of air, and even at rest.

Other indications include a zoster or shingles infection of the lower extremity as well as poor blood flow to a lower extremity. In these instances a sympathetic block can dramatically reduce the pain and improve the blood flow to allow for healing of the wound or preventing amputation.

Other indications include phantom limb pain although this is not understood as well.


after the patient is positioned facedown x-ray floor scope is used to locate the lumbar vertebral bodies particularly an upper part of. Often a light sedation is administered and then local anesthetic injected into the skin and the needle gently guided to reach the front of the vertebral body. X-ray Inc. or contrast is then injected highlighting a dark line just in front of the vertebral bodies. Local anesthetic medication sometimes would steroid is administered in this area.

Accessible block reduction of pain and a noticeable increase in warmth on the affected side. Because the sympathetic nerves control the blood vessels when block blood vessels dilate or become larger allowing greater blood flow and a resultant increase in warmth.

Contraindications are mainly related to local contraindications such as for general jazz blood thinning medication.

These blocks are sometimes repeated in a series to provide maximum reduction which hopefully will reset the bodies nerves allowing them to function normally.

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Before and After the Procedure and the Risks

Before the Procedure

Patients who take a blood thinning medication (warfarin, rivaroxaban, etc.) may need to stop taking it several days prior to the procedure. Discuss your medication with your prescribing doctor as well as the physician who will perform the injection.

The injection is usually an outpatient procedure performed in a fluoroscopy suite. Please make arrangements to have someone drive you to and from the office or outpatient treatment center.

After the Procedure

You may feel a sense of warmth or fullness in the affected leg. You may also feel some temporary numbness or weakness in the limb. You will be monitored for 15 to 30 minutes. You will be discharged when you are able walk without weakness. You cannot drive the day of the procedure. Do not swim or soak in a tub for 72 hours after the procedure.

Typically, patients resume full activity the next day. Soreness around the injection site may be relieved by using ice and taking a mild analgesic (Tylenol).

Procedure Risks

A nerve block injection is a relatively safe procedure with minimal risk of complications. Risks of a lumbar sympathetic block include bleeding, infection, allergic reaction, nerve damage, paralysis, a drop in blood pressure, anesthetic toxicity, hematuria (blood in the urine), numbness, weakness, and medication side effects.