MRI Overused for Low Back Pain, Study Shows

In a study of 2000 magnetic resonance imaging (MRI) requisitions, more than half the requests for MRI of the lumbar spine were ordered for indications considered inappropriate or of uncertain value. The data point to "evidence of substantial overuse of lumbar spine MRI scans," the investigators say.

These findings are not surprising, lead author Derek J. Emery, MD, and colleagues write in a research letter published online March 25, 2013, in JAMA Internal Medicine. "Lumbar spine MRI numbers have increased dramatically in recent years, but the correlation between lumbar spine MRI findings and clinical signs and symptoms is poor."

They note that eliminating unnecessary scans can reduce the harm associated with MRI and could lead to significant cost savings.

Dr. Emery, of the University of Alberta, Canada, and colleagues first determined appropriateness criteria using the RAND–University of California, Los Angeles, method, which included a literature review and the creation of several clinical scenarios. They then established 2 expert panels, 1 for the lumbar spine and 1 for the head. Panel members rated the appropriateness of MRI for each scenario on a 9-point scale, with 1-3 indicating an inappropriate indication, 4-6 indicating an uncertain indication, and 7-9 indicating an appropriate indication. The authors used the median score for each scenario for an ultimate evaluation of its appropriateness.

The investigators then prospectively identified 1000 requisitions for MRIs of the lumbar spine and 1000 MRIs of the head for headache ordered by physicians in a variety of specialties at the University of Alberta Hospital in Edmonton and the Ottawa Hospital in Ontario, matching each case to 1 of the clinical scenarios for which appropriateness had been established.

Only 443 (44.3%) of the lumbar spinal MRIs were deemed appropriate; of the remainder, 285 (28.5%) were inappropriate, and 272 (27.2%) were of uncertain value. Family physicians had the worst track record: "only 33.9% of their MRI scans were considered appropriate vs 58.1% of those ordered by other specialties," the authors write.

Investigation of postoperative leg or back pain was considered appropriate in 160 of 167 cases (95.8%), but they represented only 16.7% of the scans performed. In the remaining 833 cases, the probability of an uncertain or inappropriate rating was 3 times greater than the probability of an appropriate rating.

On the other hand, the vast majority of MRIs ordered for headaches — 82.8% — were deemed appropriate. Of the remainder, 9% were inappropriate, and 8.2% were of uncertain value.

Overuse of interventions and tests such as MRI is associated with adverse outcomes and cost overruns, the authors conclude. "Solutions will require strict adherence to appropriate guidelines and better education of patients."

This study was funded by a grant from the Canadian Institutes of Health Research. The authors reported no relevant financial relationships.

JAMA Intern Med. Published online March 25, 2013. Abstract