Low back pain accounts for a third of new emergency department imaging

The use of imaging for the initial evaluation of patients with low back pain in the emergency department (ED) continues to occur at a high rate–one in three new emergency visits for low back pain in the United States–according to a recent  article (Pakpoor J, Raad M, Harris A, Puvanesarajah V, Canner JK, Nadgir R, Jain A. Use of Imaging During Emergency Department Visits for Low Back Pain. AJR Am J Roentgenol. 2020 Feb;214(2):395-399. doi: 10.2214/AJR.19.21674).  “Although there has been a modest decline,” wrote Dr. Jina Pakpoor of the University of Pennsylvania, “in 2016, approximately one in three patients still continued to receive imaging in the ED.”

Excluding patients with concomitant encounter diagnoses suggesting trauma, as well as those with previous visits for back pain, Current Procedural Terminology codes were used to identify three imaging modalities: radiography, CT, and MRI.

Of the 134,624 total encounters meeting Pakpoor’s inclusion criteria, imaging was obtained in 44,405 (33.7%) visits and decreased from 34.4% to 31.9% between 2011 and 2016 (odds ratio per year, 0.98 [95% CI, 0.98-0.99]; p < 0.001).

During the five-year study period, 30.9% of patients underwent radiography, 2.7% of patients underwent CT, and 0.8% of patients underwent MRI for evaluation of low back pain.  Imaging utilization varied significantly by geographic region (p < 0.001), with patients in the southern U.S. undergoing 10% more imaging than patients in the western U.S.

Acknowledging further research is necessary “to understand the underlying reasons for persistent use of potentially unwarranted imaging in the emergency setting,” as Pakpoor concluded, “our results indicate that the use of imaging for the evaluation of patients with low back pain in the ED is moderately declining but continues to occur at an overall high rate.”