The Basics of Epidural Steroid Injections

For people who suffer from chronic neck or back pain, an epidural steroid injection (ESI) is an option to improve function and reduce pain. This procedure is minimally invasive and can offer long-term pain relief.

What medications are used in the ESI procedure?

Corticosteroids are agents that inhibit pro-inflammatory molecules to reduce pain. The pain often occurs due to inflammation, which is associated with the release of these inflammatory molecules that leads to chemical damage of nerve tissue. Corticosteroids promote normal nerve membrane formation and modulate the molecular basis of the nervous signaling.

What conditions are treated using epidural steroid injections?

ESIs are recognized as effective procedures for restoring normal function and relieving pain. They are used for cervical (neck) pain, chronic lumbar (low back) pain, and radiculopathy (pain due to damaged or compressed nerves.

Where is the steroid injected?

The protective membranes around the spinal cord extend into the skull and line the brain. Called meninges, these include the arachnoid, dura mater, and pia mater, which are distinct layers. The dura is a resilient membrane that encloses the spinal cord. The epidural space is outside the dura and around it. It is located near the bony spinal column. The steroid agent is injected into this space, where spinal nerve roots are located.

How is the epidural steroid injection done?

The patient is positioned face-down, so as to access the spine. The doctor numbs the skin and deeper tissues using an anesthetic. With fluoroscopy, the doctor inserts the procedure needle into the epidural space. Contrast dye is used to ensure accurate placement. After the needle position is confirmed, the steroid agent is injected.

Are there different ways to perform the ESI?

The approaches most often used are:

  • Interlaminar approach – This involves inserting the needle between two vertebrae to allow the steroid deliver to the nerves on the left and right sides of the spinal column. This approach is best for treating discogenic pain, spinal stenosis, neuropathy, and radiculopathy.
  • Transforaminal approach – This involves inserting the needle at an angle relative to the vertebra in the space above a particular nerve root. This approach targets nerves on one side of the spine.
  • Caudal approach – This involves inserting the needle into the epidural space of the sacral region of the spine (very low back). This is used to treat chronic back pain associated with spinal stenosis and surgery.

Does the epidural steroid injection work?

The treatment effect of an epidural steroid injection varies due to certain factors. The factor that affect ESI results include:

  • Symptoms duration before the treatment.
  • The training and skill of the doctor.
  • The disorder, condition, or disease causing the pain.

What conditions are treated using the ESI?

ESIs are often given in a series of 3, which are spaced 2-6 weeks apart. The ESI is used to treat pain associated with:

  • Intervertebral disc herniation
  • Spondylolithesis
  • Whiplash
  • Spinal stenosis
  • Vertebral fractures
  • Degenerative disc disease
  • Spinal deformities
  • Cervical or lumbar radiculopathy
  • Failed back surgery syndrome

Essentially any condition that is causing pain due to a pinched nerve or chemically irritated nerve root can benefit from an ESI.

What are the benefits of ESIs?

ESIs are used to relieve pain in patients who have not responded to other treatments. The procedure is minimally invasive, done as an outpatient procedure, and involves little recovery time. In addition, ESI can offer long-term pain relief.

How effective is the ESI?

In a study involving ESI for patients with low back pain, the success rate was found to be 81% when 62 patients were evaluated at six months after the procedure. In addition, a review of studies fund that ESI for back pain had an 89% efficacy rate.

Colorado Clinic offers top interventional pain management at several locations throughout the state including Aurora, Greeley, Loveland, Colorado Springs, Longmont, Boulder too!


Baral BK, Shrestha RR, Shrestha AB, & Shrestha CK (2011). Effectiveness of epidural steroid injection for the management of symptomatic herniated lumbar disc. Nepal Med Coll Jour, 13(4): 303-307