FAQs on Selective Nerve Root Block in Colorado


The selective nerve root block is an injection that helps relief the pain associated with irritated and compressed nerves that spur from the spinal cord. The block involves injecting a local anesthetic, corticosteroid, and/or neurolytic agent along a specific nerve root.

Why is the nerve root block done?

Along the spine, there are holes (called foramina) through which nerve roots emerge. Bulging discs, bone spurs, vertebrae shifting, and other spinal problems can cause these nerves to be compressed (pinched). The selective nerve root block will relieve the pain associated with these structures.

What symptoms are treated using the selective nerve root block?

When the spinal nerves are pinched and irritated, inflammation occurs. This can produce numbness, tingling, and pain, which can radiate into an arm or leg. The nerve block is used to relieve all these symptoms.

Will the procedure hurt?

The injection involves use of a local anesthetic, which numbs the injection area and is instilled onto the targeted nerve. You may feel some pressure during the procedure, and mild soreness at the injection site afterwards. When the doctor injects the anesthetic, some patients report feeling a slight pinch and burning sensation. As the medication hits the nerve, you can feel a mild electric zing, which is like striking your funny bone. Discomfort of the back is easily relieved by using an ice pack to the area.

Will I be asleep for the selective nerve root block?

The doctor will recommend that you receive a sedative for the procedure. This medication is given through an intravenous line, and kit keeps you very comfortable. You may have no memory at all regarding the procedure. Because a sedative is given, don’t eat/drink after midnight before your scheduled appointment.

How is the selective nerve root block done?

A nurse has you change into a gown, and places an IV in your arm. Monitoring devices are attached to your arm and finger, and you are positioned face-down on the table. Your neck or back is cleaned with an antiseptic solution, a sedative is administered in your IV, and the doctor numbs the skin and deeper tissues with a local anesthetic. The procedure is inserted through the skin and positioned near the nerve using fluoroscopy. After position is confirmed, the medication is injected onto the nerve root. The procedure needle is removed, and a small band-aid is applied.

What can I expect after the selective nerve root injection?

Immediately after the procedure, you may feel a tingling or warmth in your arm or leg, depending on what was injected. Most patients report their pain is lessened. The nurse monitors you in the recovery area for 1-2 hours. After 2-3 hours, as the anesthetic wears off, you may notice some soreness at the injection site. Use an ice pack to relieve this discomfort. We recommend you rest for 2-3 days, and gradually return to usual activities.

Does the selective nerve root block work?

In a study involving 28 patients with radicular pain related to cervical disc disease or spondylosis, researchers evaluated the effectiveness of the selective nerve root block, which involved 3 injections done 2 weeks apart. The average pain score dropped from a mean of 7.8 to 2.9 at 3 months. In addition, the success rate was 71%, with over half still having pain relief after one year. Another clinical study showed an efficacy rate of 86% when the block was used for treating sciatica.


Chung JY, Yim JH, Seo HY, et al. (2012). The Efficacy and Persistence of Selective Nerve Root Block under Fluoroscopic Guidance for Cervical Radiculopathy. Asian Spine Journal, 6(4), 227-232.

Pfirrmann CWA, Oberholzer PA, Zanetti M, et al. (2001). Selective Nerve Root Blocks for the Treatment of Sciatica: Evaluation of Injection Site and EffectivenessA Study with Patients and Cadavers. Vasc & Intervent Radiol, 221(3).