What Is Nerve Root Block?

Joint diagram

A nerve root block is an injection of a local anesthetic and steroid injected under X-ray guidance to diagnose and treat cervical, thoracic and lumbar pain and associated extremity pain in the arms or legs. It is a minimally invasive, state-of-the-art pain management treatment to help address acute and chronic pain. Nerve blocks can be used for various purposes, including:

  • Diagnostics. Diagnostic nerve blocks can help to determine sources of pain.
  • Prognostics. Prognostic nerve blocks can help predict the outcomes of given treatments, such as determining whether or not surgery would be successful in treating pain. In some cases, nerve blocks can even be used to avoid surgery.
  • Preemptive action. Preemptive nerve blocks can be used to prevent forthcoming pain from certain procedures, such as treating phantom limb pain.
  • Therapeutics. Therapeutic nerve blocks can be used to treat potential conditions. They contain local anesthetics to manage acute pain.

Conditions commonly treated with nerve root blocks include:

  • Cervical radiculopathy
  • Lumbar radiculopathy
  • Failed back surgery syndrome
  • Spinal stenosis
  • Bulging intervertebral discs
  • Herniated discs
  • Arthritis of the spine

What Can Patients Expect From a Nerve Root Block?

sisters-1328070_1280Patients normally lie under an X-ray in a fluoroscopy suite in a prone position, and the nerve root block is injected into the area where the nerve exits the spinal column through the foramen (the space between vertebral bodies). A small bit of contrast dye is also inserted to confirm proper needle placement. If the pain goes away, it’s assumed that the right nerve has been identified.

Nerve root blocks are performed in an outpatient setting and usually take less than 15 minutes to complete. A pain management specialist will most likely advise patients to take it easy for the remainder of the day, but normal activities can usually be resumed the next day.

After the procedure, patients should expect to feel numbness that follows the path of the nerve that was blocked. Most patients report that the stinging and burning of the numbing medicine is the primary cause of discomfort.

Patients may also experience certain short-term side effects, including temporary weakness, increased pain at the injection site lasting for a few days, a spike in blood sugar for diabetics due to the steroid medication.

What Are the Results of a Nerve Root Block?

The success rate of selective nerve root blocks varies among patients because some nerve roots are tougher to treat than others due to their location and surrounding structures. For some patients, pain improves immediately following the injection from the local anesthetic. The steroid typically takes two or three days to take effect – peaking in approximately two weeks.

A pain management specialist will recommend using an ice pack three or four times each day to help alleviate any tenderness. After the injection, patients can resume their normal pain medication regimen, although it is important to keep track of pain levels in order to determine how effective the nerve block was.

Symptom relief can last anywhere from a few days to a couple of months and, if necessary, the procedure can be repeated.


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