The gel-like material within a disk called the nucleus pulposus can bulge or rupture through a weak portion of the surrounding wall also known as the annulus. When this material comes in contact with the spinal nerve, irritation, pain and swelling occur.

A steroid injection can reduce inflammation when injected into the painful area. The pain relief can last from days to years, allowing your condition to improve with physical therapy. An epidural steroid injection includes both a corticosteroid and an anesthetic numbing agent.  These are injected into the epidural space of the spine. Unfortunately they do not make a herniated disc smaller, but they can alleviate the pain associated with inflammation of that area.