When Selective Nerve Root Block Injections Are Used?
Selective nerve root block injections are used to treat an inflamed nerve root caused by a herniated disc, degenerative changes in the vertebrae such as bone spurs causing nerve compression, and/or conditions such as scoliosis. In any of these conditions, there may be a chemical irritation or pinching of the nerve due to mechanical compression.
Multiple nerve blocks may be performed if more than one nerve is suspected of causing pain.
Frequently Asked Questions
When used for treatment purposes, steroids are usually mixed with anesthetics or used alone in selective nerve root block injections. Steroids in nerve blocks work by a combination of the following mechanisms:
- Inhibits the action of certain enzymes such as phospholipase A that causes neural irritation and pain
- Block specific fibers (C fibers) within the nerve that results in lesser pain transmitted to the brain
- Decreases the permeability of nerve fibers to receive blood, decreasing pain transmission
- Through these mechanisms, the pain signals transmitted by the target nerve may be reduced.
Studies evaluating the success of selective nerve root block injections have reported the following:
- In the cervical spine, 1 injection resulted in 57% of patients reporting significant improvement in pain and functional outcome at 6 months.
- In the lumbar spine, 1 injection resulted in 46% of patients reporting significant improvement in pain and functional outcome at 1 year.