Epidural Steroid Injections

An epidural steroid injection (ESI) is a procedure that involves injecting a steroid medication into the epidural space of the spine. This space is the area between the protective covering (dura) of the spinal cord and the bony vertebrae that make up the spine. The medication, typically a corticosteroid, is used to reduce inflammation and pain in the affected area of the spine. ESIs are commonly used to treat conditions such as spinal stenosis, herniated discs, and radiculopathy (nerve pain). ESIs are typically recommended as a short-term solution for pain relief and it is not considered as a permanent solution for underlying condition.

What is the goal of an epidural steroid injection (ESI)?

The main goal of an epidural steroid injection (ESI) is to reduce inflammation and pain in the affected area of the spine. By injecting a steroid medication directly into the epidural space of the spine, the medication can reach the inflamed area and reduce the inflammation and swelling that is causing pain.

Additionally, ESIs can also be used as a diagnostic tool to determine the source of pain. If a patient experiences significant pain relief after an ESI, it may indicate that the pain is coming from the affected area of the spine that was targeted by the injection.

What are the benefits of an epidural steroid injection (ESI)?

The benefits of an epidural steroid injection (ESI) include:

  1. Pain relief: ESIs can provide significant pain relief for patients suffering from conditions such as spinal stenosis, herniated discs, and radiculopathy (nerve pain).
  2. Improved function: By reducing pain, ESIs can also improve a patient’s ability to perform daily activities and exercise.
  3. Reduced need for pain medication: ESIs can help reduce the need for oral pain medication, which can have side effects and may not provide as much pain relief as the injection.
  4. Diagnostic tool: ESIs can also be used as a diagnostic tool to determine the source of pain. If a patient experiences significant pain relief after an ESI, it may indicate that the pain is coming from the affected area of the spine that was targeted by the injection.
  5. Minimally invasive: ESIs are a minimally invasive procedure that can be performed in an outpatient setting.
  6. Low risk: ESIs are considered a low-risk procedure with minimal side effects and complications.

It is important to note that ESIs are typically recommended as a short-term solution for pain relief and are not considered as a permanent solution for underlying condition. Typically, they are part of a treatment plan that may include physical therapy, medication, and/or surgery.

Which conditions are treated with epidural steroid injections (ESIs)?

Epidural steroid injections (ESIs) are a procedure used to provide pain relief for conditions that cause inflammation in the spinal nerve roots. Some of the conditions that are commonly treated with ESIs include:

  • Herniated disc: A herniated disc occurs when the soft inner material of a spinal disc bulges out through a tear in the outer layer. This can put pressure on the nerve roots, causing pain, numbness, tingling, and weakness in the legs.
  • Spinal stenosis: Spinal stenosis is a condition in which the spinal canal narrows, putting pressure on the nerve roots. This can cause pain, numbness, tingling, and weakness in the legs.
  • Radiculopathy: Radiculopathy is a general term used to describe nerve root irritation or inflammation. This can be caused by a variety of conditions such as a herniated disc, spinal stenosis, or degenerative disc disease.
  • Sciatica: Sciatica is a term used to describe pain, tingling, or weakness that radiates along the sciatic nerve, which runs from the lower back down the legs. It is often caused by a herniated disc or spinal stenosis.
  • Lumbar Facet syndrome: Lumbar Facet syndrome is a condition caused by inflammation of the small joints in the spine, that can lead to pain in lower back, buttock, and legs.

ESIs may also be used to treat other conditions that cause inflammation of the spinal nerve roots, such as degenerative disc disease, spinal arthritis, or post-laminectomy syndrome.

It’s important to discuss your symptoms and treatment options with your healthcare provider, who can perform a thorough examination and any necessary diagnostic tests to determine the cause of your pain and the appropriate treatment plan.

What to expect during the procedure

The steps of an epidural steroid injection may vary slightly depending on the approach (transforaminal, interlaminar, or caudal) being used, but the overall process is similar. Here is an overview of what a patient can expect during the procedure:

  1. Preparation: The patient will be asked to remove any clothing or jewelry that may interfere with the procedure. They will then be positioned on a table and given a local anesthetic to numb the area where the needle will be inserted.
  2. Imaging: The procedure will be done under fluoroscopic guidance, which is a real-time x-ray imaging technique used to ensure accurate needle placement. The patient will lie on their stomach or side as the physician guides the needle into the appropriate space using the imaging as a reference.
  3. Injection: Once the needle is in the correct position, the physician will inject a mixture of steroid and local anesthetic into the epidural space. The physician will then remove the needle and the patient will be moved to a recovery area to rest for a short time.
  4. Recovery: The procedure is usually done as an outpatient, and the patient can expect to feel some pain and discomfort at the injection site. They will be monitored for a short period of time to ensure that there are no complications. The pain and discomfort usually subsides after a few hours.

What are the different approaches of an epidural steroid injection (ESI)?

There are three main approaches for an epidural steroid injection:

  • Transforaminal epidural steroid injection: This approach targets a specific nerve root that is causing pain. A needle is inserted through the patient’s back and into the space around the affected nerve root. Steroids are then injected into this space, reducing inflammation and pain.
  • Interlaminar epidural steroid injection: This approach targets the epidural space in the lower back, which contains the spinal nerves. A needle is inserted into the lower back and steroids are injected into the epidural space, reducing inflammation and pain in the surrounding nerves.
  • Caudal epidural steroid injection: This approach targets the caudal epidural space, which is the lowermost part of the epidural space in the spinal canal. A needle is inserted through the patient’s sacral hiatus and into the caudal epidural space, where steroids are injected to reduce inflammation and pain in the lower back and legs.

All of these approaches are done under fluoroscopic guidance, which is a real-time x-ray imaging technique used to ensure accurate needle placement.

What are potential risks of an epidural steroid injection?

As with any medical procedure, there are potential risks associated with ESIs. These can include:

  • Infection: Although rare, an infection can occur at the injection site.
  • Bleeding or nerve damage: The needle used for the injection may accidentally damage a blood vessel or nerve.
  • Headache: Some people experience a headache after an ESI, which is caused by a leakage of cerebrospinal fluid.
  • Allergic reactions: Some people may have an allergic reaction to the medication used in the injection.
  • Failure to provide relief: The injection may not provide relief, and in some cases, the pain may actually worsen.

How effective are epidural steroid injections?

In general, studies have shown that ESIs can provide significant pain relief for some people with certain types of back and leg pain. A systematic review of studies on ESIs for herniated discs found that the procedure provided moderate to good pain relief for about 50-70% of patients.

How long do epidural steroid injections last?

The duration of pain relief from an epidural steroid injection (ESI) can vary depending on the individual patient and the condition being treated.

Some studies have found that pain relief from ESIs can last for several weeks or months. For example, a study of patients with herniated discs found that the average duration of pain relief from ESIs was about 10 weeks. Another study of patients with spinal stenosis found that the average duration of pain relief from ESIs was about 12 weeks.

However, it’s important to note that the relief provided by ESIs may not be the same for everyone and may not provide any relief at all. 

Is an epidural steroid injection right for me?

The decision to receive an ESI should be made on a case-by-case basis, after a thorough evaluation by a healthcare provider.

ESIs may be considered for patients who have not responded to more conservative treatments such as physical therapy, medications, and activity modification, and have symptoms such as radicular pain, numbness, tingling, or weakness caused by inflammation of the nerve roots.

The procedure may not be suitable for everyone, for example, it’s generally not recommended for patients who have an active infection, a bleeding disorder, or have certain types of cancer. People who have had an allergic reaction to the medications used in the injection should also be cautious.

It’s important to have a discussion with a healthcare provider experienced in performing the procedure, who can evaluate your condition, discuss the risks and benefits, and help you make an informed decision about whether an ESI is the right option for you.

About the Author

Dave Harrison, MD

Dr. Harrison is a board certified Emergency Physician with a part time appointment at San Francisco General Medical Center and is an Assistant Clinical Professor-Volunteer at the UCSF School of Medicine. Dr. Harrison attended medical school at Tufts University and completed his Emergency Medicine residency at the University of Southern California. Dr. Harrison manages the editorial process for SpineInfo.com.