What are the reasons for performing a selective nerve root block?

The nervous system is the control and transmission system of the human body. The nervous system is composed of various important structures, such as the brain, the brainstem, the spinal cord, the nerve roots, as well as the various nerves throughout the body. It serves as the transmission network for signals from one part of the body to another.Sciatica Treatment Boulder CO

The nervous system directly and indirectly controls bodily functions through the autonomic nervous system, which is loosely grouped into the sympathetic and parasympathetic nervous system.

These nerves control functions such as heart rate, blood pressure, digestion, sweating, and blood flow (i.e., prioritizing where to shunt blood). Trunks of the sympathetic nerves are grouped and found along the front side of our spinal column.

The nervous system exerts its control through the regulated transmission of signals. However, sometimes the transmission of signals goes haywire, causing excessive stimulation of the nervous system.

One of these diseases is Complex Regional Pain Syndrome (also known as Reflex Sympathetic Dystrophy), which causes excessive stimulation of the sympathetic nervous system. Diseases such as herpes zoster (or shingles) make the nervous system hypersensitive, leading to excessive pain sensation. Chronic pain can also be caused by local irritation, such as from degenerative diseases that cause irritation to the nerve roots or from compression from space-occupying lesions, or from growths.

Boulder pain managementA selective nerve root block addresses these conditions by interrupting, or blocking, the transmission of signals from the nervous system. This is done through a minor outpatient procedure.

The needle is inserted under fluoroscopic (X-ray) guidance, going through muscle and tissue until the target area is reached. Other guiding modalities have been of use in recent years, such as computerized tomography (CT), magnetic resonance imaging (MRI) and ultrasonography. Local anesthetic is then introduced into the area.

A successful block is confirmed by the relief of the symptoms caused by excessive nerve stimulation. Pain symptoms are typically relieved within minutes, and signs of relief from sympathetic overstimulation (such as in cases of RSD) such as lessening of reddening, an increase in temperature, and relief of pain are taken as signs of a successful block.

Selective nerve root blocks are done for both therapeutic and diagnostic reasons. It is a diagnostic tool for identifying the level of the lesion in cases of chronic pain. The nerve root block serves as a preparatory procedure to identify the target nerve root is the source of an individual’s pain. For instance, a Boulder pain management doctor may think sciatica is causing an individuals’ leg pain but not see nerve root compression on the MRI.

The selective nerve root block can see if in fact the nerve root is the source of pain. Maybe it was simply being “chemically irritated” from a tear in the nearby spinal disc?

In some cases, a long-acting anesthetic is inserted together with a corticosteroid, which is a powerful anti-inflammatory medication, to provide long-term pain relief. This may require repeat injections up to three or four times a year.

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