Thinking Twice on MRI for Back Pain

MRI prior to lower back injection debated

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) You're at the doctor for your lower back pain, and he's considering giving you an epidural to relieve the pain. If he asks for a MRI before he decides, ask him if it's absolutely necessary.

A new study, published in the Archives of Internal Medicine, examines the usefulness of ordering an MRI before giving an epidural steroid injection (ESI).

The researchers say that it's become routine to use an MRI to make a decision on the injection, but not doing so would save significant time and resources for the health care system.

They found that MRI made only a minor difference in the doctor's decision making, and does not significantly improve life for the patient.

"Ask your doctor to reconsider MRI before an ESI."

The study was led by Dr. Stephen Cohen of the Johns Hopkins School of Medicine. In the study, he and his colleagues write that low back disorders are an extremely common condition. They're responsible for a growing proportion of medical costs, but there's a lot of uncertainty about which of an array of possible treatments is best for the patient.

ESIs are among the most common choices for treatment for lower back pain and sciatica. The injections provide temporary relief from pain that can last from a week to a year.

As the use of ESIs have increased, so has the use of advanced spinal imaging. Despite the upward trend, the authors say that outcomes – overall improvement in quality of life – do not seem to be improving for sufferers of chronic back pain.

As background for their study, the authors questioned the effectiveness of the epidurals as a long-term treatment. They write, “...It appears that much of the use of epidural steroid injections occurs in these situations of uncertain benefit.”

Magnetic resonance imaging (MRI) is used to “rule out” other conditions that may make it unsafe to do an injection on a patient. But the researchers say there isn't a lot of evidence that this works, either.

Dr. Cohen and his colleagues wanted to learn whether MRI really does improve the outcomes for patients who receive ESIs for their lower back pain. They created a randomized study for 132 patients.

All patients had an MRI, but they were divided into two groups. The physician for group one could not look at the MRI results before deciding on treatment, but an independent physician recommended treatment by looking at the MRI. That was compared to the treatment the patient actually received.

The physician for group two used the MRI results. It turned out that all of the patients from group one got ESIs, but not all patients in group two did. The patients who didn't get ESIs left the study.

In 80 percent of cases in first group, the only difference between their actual treatment by the physician blinded to the MRI results, and the recommended treatment by the doctor who saw the results was which type of epidural they would receive, or performing the same injection at a different level.

The study concluded that although MRI may have an effect on decision making, it is “unlikely to avert a procedure, diminish complications, or improve outcomes.” They believe that not routinely ordering an MRI may save time and health resources.

The paper was published online on December 12, 2011.

Reviewed by: 
Review Date: 
December 14, 2011
Last Updated:
December 17, 2011