This study is an analysis of the National Hospital Ambulatory Medical Care Survey (NHAMCS), a large sample representative of all emergency department (ED) visits throughout the United States.
To use NHAMCS to describe the frequency of ED visits for the treatment of low back pain, and the diagnostic and therapeutic strategies employed by emergency clinicians.
Low back pain is common in the general population. While it accounts for 2.5% of all outpatient office visits, the role of the ED has yet to be described.
We included cases if they had both a reason for visit related to back pain and a primary ED discharge ICD9 code consistent with low back pain. The outcomes included frequency of ED use, and frequency of various diagnostic and therapeutic strategies. Individual patient visits are weighted so that data can be extrapolated to all ED visits throughout the United States.
Low back pain related disorders caused 2.63 million (95% CI: 2.32, 2.93 million) annual ED visits in the US. Of all patients with low back pain, 30.5% (28.1, 32.9) had a plain radiograph; 9.6% (95% CI: 7.2, 12.6) had a CT or MRI in 2006 compared with 3.2% (95% CI: 2.0, 5.1) in 2002 (P for trend <0.01). Age and type of insurance were associated with advanced imaging, though geographic region was not. Of medications either administered in the ED or prescribed at discharge, the most frequently used classes were opioids (61.0%, 95% CI: 58.4, 63.5), followed by nonsteroidal anti-inflammatory drugs (49.9%, 95% CI: 47.2, 52.7) and muscle relaxants (43.1%, 95% CI: 40.4, 45.8).
Low back pain related disorders are a frequent cause of ED visit. Diagnostic imaging is performed in one-third of all patients. There was a strong secular trend in use of advanced imaging; patients were nearly 3 times as likely to receive a CT or MRI in 2006 as they were 4 years earlier. Although opioids were administered or prescribed to two-thirds of patients, use of therapeutic agents was generally in keeping with guideline recommendations.
We analyzed a representative sample of emergency department visits throughout the United States to describe the frequency of visits for the treatment of low back pain related disorders, and the diagnostic and therapeutic strategies employed. Low back pain related disorders are a frequent cause of emergency department visit. Diagnostic testing was performed in nearly half the patients. Use of therapeutic agents was generally in keeping with guideline recommendations.
From the Department of Emergency Medicine, Albert Einstein College of Medicine, Bronx, NY.
Acknowledgment date: July 31, 2009. First revision date: November 2, 2009. Second revision date: December 16, 2009. Acceptance date: January 25, 2010.
The manuscript submitted does not contain information about medical device(s)/drug(s).
No funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript.
Supported by a career development award (1K23NS051409) from the National Institute of Neurological Disorders and Stroke (to B.W.F.).
Presented at the Society For Academic Emergency Medicine Annual Meeting; May, 2009; New Orleans, LA.
This study was administratively reviewed by the Montefiore Medical Center Institutional Review Board and determined to be exempt from IRB purview.
Address correspondence and reprint requests to: Benjamin W. Friedman, MD, Department of Emergency Medicine, Albert Einstein College of Medicine, Montefiore Medical Center, 111 East 210th Street, Bronx, NY 10467; E-mail: email@example.com.