Selective Nerve Root Block

One of the causes of pain that passes into the extremities is irritation of one or more nerve roots. The purpose of a selective nerve root block (SNRB) is to block one or more spinal nerves to decrease pain. This is done by injecting an anesthetic and anti-inflammatory steroid into the space around the nerve. It is similar to an epidural steroid injection. This will help determine which particular nerve is related to your symptoms. SNRB is used to evaluate patients with radicular pain, stenosis and other conditions that may result in nerve root compression. 

Before the Procedure

  • Do not eat or drink anything after midnight before your injection.
  • You can take your regular heart and blood pressure medications on the morning of the injection with a sip of water. Diabetes medications should not be taken.
  • Discontinue taking anti-inflammatories three days before the injection.
  • Discontinue taking aspirin products seven days before the injection.
  • If on blood thinners, call the physician who prescribed the medication to get approval to stop taking them before the injection. 

During the Procedure

  • You will lie on a table in a procedure room.
  • The skin in the area where the injection will be made will be cleaned.
  • The skin is numbed with lidocaine.
  • Using fluoroscopy (live x-ray) for guidance, the physician directs a needle toward the area of the nerve root to be evaluated.
  • The anesthetic and steroid solution is injected.
  • The injection procedure will take about 30 minutes.

After the Procedure

  • You will be in a recovery room for about 30 minutes.
  • It is important that you have someone to drive you home.
  • It is common to experience an increase in pain once the numbing medicine wears off.
  • The steroid does not become effective for 24 hours.
  • Activity should be restricted for the first 4-5 days after the injection.
  • You will need to make an appointment with your doctor to discuss your level of pain relief after the injection.