The sympathetic nerves are a group of nerves found along the front side of the spinal column. They are part of the autonomic nervous system and control many bodily functions including sweating, heart rate, digestion, and blood pressure. Sometimes these nerves can continue to transmit pain following an injury even after the injury has healed. This can result in a condition known as Chronic Regional Pain Syndrome (CRPS), also known as Reflex Sympathetic Dystrophy (RSD). Symptoms of CRPS include severe burning pain, swelling, and skin color changes.

A lumbar sympathetic nerve block is a special test to help your doctor find the cause of your symptoms. During the test, an anesthetic (numbing) medication is injected near your spine. This “blocks” the sympathetic nerves in that region. If these nerves are causing your symptoms, the injection may offer relief for a while immediately after the procedure. If effective, your doctor may recommend a series of these blocks 1-2 weeks apart which may help give you more long term pain relief.