Selective Nerve Root Block; Diagnostic And Therapeutic Care In Various Conditions

The selective nerve root block (SNRB) is a procedure which has been using in pain management. SNRB is of great importance due to its diagnostic and therapeutic advantages. SNRB is also known as a transforaminal epidural injection.

Doctors are using SNRB because it allows the doctor to determine what nerve root or maybe roots are being affected.  SNRB can be a diagnostic test or therapeutic test and it depends on the type of medications that are injected. Usually steroids are using in SNRB.

When using for diagnostic purpose, it helps the doctor to find out which nerve is involved in symptoms. And during therapeutic test SNRB provide pain relief.

When to perform SNRB?

SNRB generally performed to diagnose cervical (neck) or lumbar (low back) radiculopathy which is irritation and inflammation of a nerve root.

The goal of injection is to reduces the inflammation and pain which caused by pressure on the nerve.

How SNRB works?

When SNRB are using for treatment purpose, steroids are usually mixed with anesthetics or used alone in selective nerve root block injections.

  • Steroids inhibit the action of certain enzymes such as phospholipase A that causes neural irritation and pain.
  • Block specific fibers (C fibers) within the nerve that ultimately results in lesser pain transmitted to the brain.
  • Decreases the permeability of nerve fibers to receive blood, decreasing pain transmission.

Conditions on which SNRB can used:

  • Selective nerve root block injections are used to treat an inflamed nerve root caused by a herniated disc.
  • SNRB can also use in degenerative changes in the vertebrae such as bone spurs, which cause nerve compression.
  • In condition such as scoliosis, SNRB is also useful. Scoliosis is a condition in which the spine curves to the left or right and creating a C- or S-shaped curve.

In any of these conditions, there may be a chemical irritation or pinching of the nerve due to mechanical compression.

Success rate:

57% of patients reports significant improvement in pain, when SNRB is using for cervical spine. Also their cervical spines become functional right after 6 months of injection.

46% of patients reports significant improvement in pain and functional outcome at 1 year, when SNRB is using for lumbar spine.


  • Bleeding
  • Infection
  • Allergic reaction to the medications
  • Puncture of the membrane that covers the spinal cord
  • Nerve damage
  • Paralysis
  • Headaches


Zaki Anwar MD is an Anesthesiologist and Interventional Pain Management Specialist. He has vast expertise for the diagnosis and treatment of back pain, headaches, migraines, neck pain, sciatica pain and various pain conditions.

For further queries call on 815-412-6174