Epidural Steroid Injections

Epidural steroid injection procedures are performed to relieve low back pain, radiating leg pain, and sciatica. Steroid medication can moderate some of the inflammation and swelling caused by spinal conditions such as sciatica, degenerative disc disease, spinal stenosis, and radiculopathy. Low back pain and radiating leg pain are two of the most common symptoms that are relieved by the epidural steroid injections.

How epidural steroid injections work. Epidural steroid injection are the most effective in patients whose cause of back pain or pain radiating down the limbs is due to inflammation of the epidural space - the space just outside the dura mater (the outer layer of the spinal cord). The epidural space in the spine is composed of blood vessels, fatty tissue, spinal nerve roots, and lymphatics. Due to structural stability due to degenerative diseases, arthritis, or injury, the epidural space may become inflamed or irritated, and the structures such as the spinal nerve roots in this area may become sensitive to these changes and send pain signals to the brain. With this procedure, a cortisone, or steroid is delivered directly to this epidural space to reduce inflammation, therefore reducing pain.

The procedure: The patient gently climbs onto the medical table, and lies on their stomach, with a cushion under the stomach to flex the back and provide comfort. In this position, the spine opens and allows for easier access to the epidural space. Next, the skin around the area where the epidural needle is numbed with a local anesthetic. All the tissue down to the surface of the lamina portion of the lumbar vertebra is anesthetized. With these tissues numbed in preparation for the epidural injection, a fluoroscope is used by the doctor to locate the inflamed/irritated nerve root or lumbar vertebra. When the physician has found the appropriate structures, the larger needle containing the steroid medication is inserted through the anesthetized track. Using the fluoroscope for direction, the needle is carefully guided to the epidural space between the two vertebrae with tissue inflammation (typically, between L4-L5 for lumbar steroid injections, and the epidural space between L5-S1 for irritation to the sacroiliac joint).



When the needle is near the site of medication delivery, a contrast dye is injection to give the physician a clearer picture of the inflamed tissues causing the back pain or radiating leg pain to confirm the correct location of the needle tip. Once the needle is in the appropriate position, a steroid-anesthetics mixture is injected into the epidural space. This corticosteroid medication is meant to reduce inflammation to inflamed joints. The effect of the steroid injection (back pain relief) may be immediate or develop over the next few days, if successful.

After the delivery of the medication, the needle is slowly withdrawn, and a small bandage is secured over area where the needle entered the skin.

The results may vary for each patient, with some patients experiencing immediate pain relief the first time that they had the procedure, while some patient may first experience significant relief the day after their third procedure. The results also vary among the patients who do experience significant pain relief from the injections. Some patients may experience pain relief for a matter of days, while other patient may experience pain relief for months, or even forever, if the cause of the back pain was a condition that corrected itself while the steroid medication was performing its anti-inflammatory magic. Results may vary for each patient.