Myth – MRI the Back and They Won’t Return to the ED

November 17, 2017

Spoon Feed
Getting an MRI for back pain does not reduce recurrent patient visits within a week.  The only time we should get an MRI for back pain in the ED is if there is a clinical concern that the findings may prompt emergent surgery, such as for cauda equina, epidural abscess, or impinging mass (may need radiation), etc.

Why does this matter?
Sometimes patients present with severe back pain and may request an MRI.  One would think that if we capitulate and do one, they would be satisfied that there is no emergent surgical cause for their pain, and this would decrease return visits in the short run. Let’s see how well that worked out.

And, he’s back…
This was a retrospective study of 6094 patients presenting to the ED with back pain.  Of these, 13% received an MRI.  About 4.5% of patients returned to the ED within 7 days, and that was the same regardless of whether an MRI was performed or not.  Patients who got an MRI were more often admitted for observation.  And length of ED stay was almost doubled: 4.8 hours for MRI vs 2.7, no MRI.  This practice has a few downsides.  It is expensive.  It is inefficient for patients.  It is a poor utilization of ED bed space.

Source
Association of magnetic resonance imaging for back pain on seven-day return visit to the Emergency Department.  Emerg Med J. 2017 Oct;34(10):677-679. doi: 10.1136/emermed-2016-206250. Epub 2017 May 2.

Peer reviewed by Thomas Davis, MD.