Procedure Description
A diagnostic selective nerve root block (SNRB) is a minimally invasive, image-guided procedure used to determine which spinal nerve root is causing pain. A small amount of local anesthetic (and sometimes steroid) is injected near a specific nerve root exiting the spinal canal.
This test is not designed to treat pain long term, but rather to confirm the exact nerve responsible for symptoms such as radiating pain, numbness, or weakness—often in preparation for spine surgery or targeted therapy like radiofrequency ablation.
What It Treats
A selective nerve root block is used for diagnostic purposes to identify pain caused by:
Cervical, thoracic, or lumbar nerve root compression
Herniated disc
Spinal stenosis
Degenerative disc or facet joint disease
Radiculopathy (pain radiating into the arm or leg)
This procedure helps determine whether a specific nerve root is the source of symptoms such as:
Sciatica (lumbar radiculopathy)
Neck pain with arm radiation (cervical radiculopathy)
Burning, shooting, or electric-like pain along a nerve path
How It Is Performed
You will lie on an X-ray table (face down for lumbar, face up or side for cervical).
The skin over the injection site is cleaned and numbed with local anesthetic.
Under fluoroscopic (X-ray) guidance, a thin needle is advanced near the targeted nerve root opening (foramen).
A small amount of contrast dye is injected to confirm correct needle placement.
A small dose of local anesthetic (and sometimes steroid) is injected around the nerve root.
You will be monitored to assess whether your typical pain is relieved or reproduced, helping confirm the nerve’s role in your symptoms.
The procedure typically takes 10–15 minutes.
Pre-Procedure Instructions
Do not eat or drink for at least 6 hours prior if sedation is planned.
Take your regular medications unless instructed otherwise; you may need to pause blood thinners several days in advance.
Inform your provider if you:
Have any allergies to iodine, contrast dye, or anesthetics
Are pregnant or suspect pregnancy
Have a fever, infection, or recent illness
Wear loose, comfortable clothing, and arrange for a driver if sedation is used.
What to Expect After the Procedure
You may experience immediate pain relief, typically lasting a few hours if the targeted nerve is the source of your symptoms.
Some patients report mild soreness at the injection site.
Because this is a diagnostic procedure, the goal is to determine if pain improves temporarily—this will help your physician plan further treatment.
A pain diary or questionnaire may be provided to track your pain level over several hours post-procedure.
You may return to light activity the same day but should avoid heavy lifting or strenuous activity for 24 hours.
Contact your provider if you experience:
Fever, chills, or signs of infection
New or worsening numbness, weakness, or pain
Severe headache or difficulty urinating
Targeted Diagnosis for Smarter Spine Care
At Parkview Spine & Pain, we use diagnostic selective nerve root blocks to pinpoint the exact cause of nerve-related back and neck pain. This precise approach ensures the most effective treatment—whether surgical, interventional, or rehabilitative.
👉 Schedule a consultation today to determine if a selective nerve root block is the right step in your diagnosis and treatment plan.