Epidural Steroid Injection: What Is It and Why Is it Used?

An Epidural Steroid Injection (ESI) is a corticosteroid injection given to the spine’s epidural space to relieve pain. The epidural space is between the dura mater and the vertebral column. It contains fats, small blood vessels, and nerves. An epidural injection provides temporary relief from pain that can be effective from one week to a year.

Epidural steroid injections in the cervical, thoracic, lumbar, or sacral regions of the spine are possible. It is effective for acute leg or back pain, weakness, numbness, or tingling caused by a nerve compression on the spine. Contact Carolina Spine and Pain Center for more information on Greenville injections for pain relief.

How Does an Epidural Steroid Injection Work?

Steroids act as an anti-inflammatory agent. Inflammation is linked to various low back disorders, and lowering it helps ease discomfort. After injecting epidural steroids into the spine’s epidural space, fluid such as local anesthetic or normal saline solution is administered to help ‘flush out’ inflammatory mediators that may be causing pain in the area.

Triamcinolone acetonide, Dexamethasone, and Methylprednisolone acetate are the most common steroids. Lidocaine (Xylocaine), a fast-acting local anesthetic for transient pain relief, is preferred for local anesthesia. Bupivacaine is a longer-lasting alternative to lidocaine.

A corticosteroid work by the following mechanisms:

  • They control the inflammatory response to pain caused by chemical substances from a herniated or a degenerative disc. Steroids synthesize specific inhibitors to stop the release of these chemicals.
  • They reduce the immune system’s activity to limit the body’s production of inflammatory cells.
  • Steroids reduce spontaneous nerve signals arising from inflamed, irritated, or compressed nerves, which helps to minimize continuous nerve discomfort.

When Is an Epidural Steroid Injection Administered?

Epidural steroid injections relieve back pain from spinal stenosis, foraminal stenosis, herniated disc, lumbar radiculopathy, and degenerative disc degeneration. The physician can administer these injections in the neck, mid-back, or lower back/buttocks. In addition, the injections reduce discomfort radiating from these areas into the arms and legs and, less commonly, the chest and thorax.

Routes of Administration

Injecting medication into the epidural area can be done in many ways. The doctor will choose the best method for you based on your diagnosis and if you have had any prior spine procedures. The injection is administered correctly with X-ray (fluoroscopic) guidance and confirmed through contrast-enhanced imaging.

These are some of the ways of epidural steroid injections are given:

  • Caudal Injection 

Caudal injection is the easiest and less specific method of gaining access to the epidural region. The needle is inserted into the sacral area beneath the lumbar spine through an opening known as the sacral hiatus. If multiple portions of the spine are involved, or if post-surgical modifications limit alternate techniques, it may be beneficial.

  • Interlaminar Injection 

An interlaminar (or translaminar) injection sends the medication directly into the epidural space at the affected level. To reach the epidural space, the needle is placed into the area between the adjacent vertebral laminae (posterior wall of the vertebra). It can treat many levels at once and can be targeted to one side or the other.

  • Transforaminal Approach

A transforaminal injection delivers medication to the area where a herniated disc compresses the injured nerve root as it exits the spine. It is the most common way to administer an epidural injection.

The needle is inserted into the epidural space through the intervertebral foramen, located on the side of the spinal canal. The safe triangle, which is located above the spinal nerve as it exits the neuroforamen, is where the needle passes to reach the epidural area. It is also known as the supraneural approach.

Risk of Epidural Steroid Injection

Any procedure requiring a needle carries the risk of bleeding, infection, and nerve injury. However, when done correctly, any of these risks are highly minimal and usually outweighed by the procedure’s potential benefit.

Except for temporary localized pain after the injection, very few risks are associated with this procedure. The physician may puncture the sack containing the spinal fluid during the procedure on rare occasions.

The following are some of the contraindications to administering epidural steroid injections:

  • Bleeding disorders or anticoagulation
  • Systemic infection or localized infection overlying the area
  • Medication allergies in rare cases

Side Effects of Using an Epidural Steroid Injection

Side effects after an epidural are usually minor. A few examples are but are not limited to:

  • Nausea
  • Headache (less common)
  • Dizziness
  • Mild injection site pain
  • Temporary worsening of the usual pain
  • Temporary weight gain
  • Fainting due to anxiety from the procedure causes a sudden drop in heart rate and blood pressure (vasovagal attack)
  • Facial flushing – redness and a feeling of warmth

These adverse effects typically resolve with rest. They are usually self-limited and resolve within one to three days. If there is any pain or swelling at the injection site, it can be treated with cold therapy using ice packs.

The Complications of Epidural Steroid Injection

Serious problems are possible after getting Greenville injections for pain relief, including epidural steroid injections. The following are the possible complications of epidural steroid injection:


Infections may spread throughout the body from the injection site and may affect the brain and spinal cord. Here are some examples:

  • Epidural Abscess: It is the accumulation of pus in the epidural space.
  • Soft Tissue Abscess: A collection of pus within the soft tissues at the site of injection.
  • Meningitis: It is the inflammation of the brain and spinal cord membranes.
  • Osteomyelitis: This refers to the infection of the vertebral bone or disc.

Microbes from the patient’s skin are believed to be a common cause of infections.

Dural Puncture

A dural puncture occurs if the needle is accidentally inserted into the outer membrane of the spinal cord (dura mater). This infection is also known as a wet tap, and it happens when the cerebrospinal fluid (CSF) leaks out, lowering CSF pressure in the brain and causing a headache.


Damage to arteries results in localized bleeding and blood pooling in the soft tissues, epidural space, or spinal membranes. In addition, a hematoma, or blood clot, can form within an artery, cutting off blood flow to important organs like the brain and spinal cord.

Nerve Damage

Damage to nearby nerves can result in strange sensations, sensory loss, or convulsions. Cauda equina syndrome is a medical emergency that occurs when the cauda equina nerves at the base of the spinal cord are injured. This syndrome involves bowel and bladder control loss and must be treated right away to avoid lower-body paralysis.

Contact Us Today for the Best Greenville Injections for Pain Relief

If you are looking for the best injury treatment center near me in Greenville, contact us at Carolina Spine and Pain Center. We specialize in discovering, diagnosing, and treating acute and chronic back, spine, and joint disorders. Reach out to us today to schedule a consultation.