The epidural steroid injection (ESI) is the placement of cortisone, a powerful anti-inflammatory agent, into the epidural space, which approximates the disc and spinal column. The epidural injection has been used for over 40 years as treatment for back pain. It involves using either steroids or anesthetic agents allowing good benefits with minimal risk factors. The main goal of the epidural injection is to shrink the swelling in bulging or herniated discs, and to decrease any inflammation that surrounds the disc and may be pressing on a spinal nerve. This is a common procedure. Because of the low risk and low incidence of any significant problems or side effects, this is felt to be a reasonable procedure to follow when traditional conservative therapy for disc pain has failed to provide improvement. A large percentage of patients upon whom this procedure is performed will get complete resolution of symptoms; a small percentage may experience no real improvement at all.
If there is improvement from the steroid epidural, it likely will occur over the next several days to two weeks. The improvement should not be expected immediately.