The back is a complicated structure of bones, joints, ligaments and muscles. You can sprain ligaments, strain muscles, rupture disks, and irritate joints, all of which can lead to back pain. While sports injuries or accidents can cause back pain, sometimes the simplest of movements—for example, picking up a pencil from the floor—can have painful results. In addition, arthritis, poor posture, obesity, and psychological stress can cause or complicate back pain. Back pain can also directly result from disease of the internal organs, such as kidney stones, kidney infections, blood clots, or bone loss.

• Low back pain is the single leading cause of disability worldwide, according to the Global Burden of Disease 2010.
• One-half of all working Americans admit to having back pain symptoms each year.
• Back pain is one of the most common reasons for missed work. In fact, back pain is the second most common reason for visits to the doctor’s office, outnumbered only by upper-respiratory infections.
• Most cases of back pain are mechanical or non-organic—meaning they are not caused by serious conditions, such as inflammatory arthritis, infection, fracture or cancer.
• Americans spend at least $50 billion each year on back pain—and that’s just for the more easily identified costs.
• Experts estimate that as many as 80% of the population will experience a back problem at some time in our lives.

Herniated discs can occur in people of all ages. They are most common in people between 35 and 45 years old.

Many people have a herniated disc in the back and are not aware of it, because they have no symptoms of leg or back pain. But for some people, herniated discs do cause leg or back pain, or nerve-related problems.

Of people with low back or leg pain, 4% have nerve-related problems triggered by a herniated disc. Other nerve-related problems include spinal stenosis, fractures, and infections.

Herniated discs are common in people whose jobs require sitting at desks or driving motor vehicles for long periods of time.

How It Works

An epidural steroid injection (ESI) is a combination of a corticosteroid with a local anesthetic pain relief medicine. Corticosteroids are strong anti-inflammatory medicines used to relieve pain. The local anesthetic medicine helps give you immediate pain relief. Corticosteroid medicines take longer to have an effect.

An ESI is injected into the space around the spinal cord and nerve roots (epidural space). The injection does not go into the membrane (thecal sac) that contains the spinal cord and nerve roots.

ESIs sometimes are used to treat pain and inflammation from pressure on the spinal cord. ESI is usually not tried unless symptoms caused by lumbar spinal stenosis have not responded to other nonsurgical treatment.

Imaging tests, such as magnetic resonance imaging (MRI) or computed tomography (CT) scans, are usually done before you are given the injection. These tests are used to identify the exact location where nerve roots are being squeezed. During the injection, an X-ray machine (fluoroscope) is often used to guide placement of the needle.

Why It Is Used

An epidural steroid injection (ESI) may be tried when other nonsurgical treatments have failed to relieve severe leg pain from lumbar spinal stenosis.

The corticosteroids in an ESI can help provide relief from leg pain by reducing swelling and inflammation. Local anesthetics help relieve pain but do not reduce inflammation. Lidocaine can also help relieve pain quickly, before the corticosteroid has taken effect.