Lumbar Epidural Steroid Injections (LESI)

A lumbar epidural steroid injection (LESI) is an injection of corticosteroids (similar to cortisone) into the space just outside the covering (the dura) of the spinal cord in your lower back. Because the injection is outside (epi) the dura, it is called an epidural injection.


What are the indications for a lumbar epidural steroid injection?

These injections are performed when it is thought that spinal nerve inflammation is part of the process that is causing the pain. Common indications for LESI include herniated discs, degenerative disc disease, radiculopathy or radiculitis, and spinal stenosis.

How do epidural steroid injections work to control my pain?

The spinal cord travels from the brain to the waist in a tunnel in the back part of the spine. About every inch along the way, the spinal cord gives off branches (spinal nerves) to the right and left. These spinal nerves carry sensations and pain signals from the various parts of the body back to the brain. Corticosteroids are very potent anti-inflammatory medications that work best when they are injected into the area where the inflammation is occurring. Because the spinal nerves pass directly through the epidural space, a LESI allows the medication (steroid) to come into direct contact with the inflamed spinal nerves, reducing the pain associated with the inflammation.


How do I prepare for the procedure?

You should not eat or drink anything for at least 2 hours before your procedure. You should take all of your medicines except blood thinners the day of your procedure.

What should I expect during the procedure?

A local anesthetic will be injected into your skin to make it numb. The epidural needle will be inserted through the numbed skin and slowly advanced into the epidural space using fluoroscopy (live X-rays) to guide the needle. Once the needle is in the epidural space, a small amount of contrast will be injected under live X-ray to ensure that the medication will spread properly. After this, the corticosteroid will be slowly injected into the epidural space. Once the injection is complete, the needle will be withdrawn and a dressing will be placed over the injection site.


What can I expect after the procedure?

Some patients will experience immediate relief, however, it usually takes 24 to 72 hours for the effects of the steroid medication to take effect and it may be up to 1 week before the maximum benefits are achieved. Very often more than 1 injection is necessary to achieve a good level of pain relief.

Common Conditions Treated by Lumbar Epidural Steroid Injections