With an epidural steroid injection, a steroid or corticosteroid medication is injected into a part of the spine called the epidural space. The goal is to help reduce certain kinds of back pain.

“Chronic back pain is common and can negatively impact a person’s quality of life, making it difficult to move, sleep and participate in daily activities,” said author Carmel Armon, MD, of Loma Linda University School of Medicine in California and a Fellow of the American Academy of Neurology. “In our review, studies show epidural steroid injections may have limited efficacy. They may modestly reduce pain in some situations for up to three months and reduce disability for some people for up to six months or more.”

For the review, researchers analyzed all available studies over a 16-year period. A total of 90 studies were examined.

The review focused on the use of epidural steroid injections to reduce pain for people with radiculopathy and spinal stenosis. Radiculopathy is a condition caused by a pinched nerve in your spine. Spinal stenosis is a condition where your spinal cord or nerves have become compressed because the space around your spinal cord has become too small.

For people with radiculopathy, the review says studies show epidural steroid injections may be effective at modestly reducing pain and disability for up to three months after the procedure.

When compared to people not receiving the treatment, 24% more people receiving the treatment reported reduced pain, and 16% more reported reduced disability for up to 3 months. The treatment may also reduce disability for up to six months or more, with 11% more of those treated reporting reduced disability.

Most of the reviewed studies looked at people with radiculopathy in their lower backs, so it is unclear how effective the treatment is for those with radiculopathy in their necks.

For people with spinal stenosis, studies show epidural steroid injections might modestly reduce disability for up to six months or more after the procedure.

When compared to people not receiving the treatment, 26% more people receiving the treatment reported reduced disability up to three months, and 12% more for up to six months or more. The treatment was not found to reduce pain for up to three months.

All studies looked at people with stenosis in their lower backs, so researchers do not know how effective the treatment is for people with stenosis in their necks.

“Our review affirms the limited effectiveness of epidural steroid injections in the short term for some forms of chronic back pain,” said author Pushpa Narayanaswami, MD, of Beth Israel Deaconess Medical Center in Boston and a Fellow of the American Academy of Neurology. “We found no studies looking at whether repeated treatments are effective or examining the effect of treatment on daily living and returning to work. Future studies should address these gaps.”