Low back pain reportedly occurs at least once in 85% of adults younger than 50 years, and 15-20% of Americans have at least one episode of back pain per year. Of these patients, only 20% can be given a precise pathoanatomic diagnosis. Low back pain affects men and women equally. The onset most frequently occurs in people aged 30-50 years. Low back pain is the most common and most expensive cause of work-related disability in the United States. Smokers appear to have an increased incidence of back pain compared with nonsmokers. Furthermore, the incidence of current smoking and the association with low back pain is higher in adolescents than in adults.
The American College of Radiology (ACR) has published appropriateness criteria for low back pain, including the following:
- Uncomplicated acute low back pain and/or radiculopathy are benign, self-limited conditions that do not warrant any imaging studies.
- MRI of the lumbar spine should be considered for those patients presenting with red flags raising suspicion for a serious underlying condition, such as cauda equine syndrome, malignancy, or infection.
- In patients with a history of low-velocity trauma, osteoporosis, or chronic steroid use, initial evaluation with radiographs is recommended.
- In the absence of red flags, first-line treatment for chronic low back pain remains conservative therapy with both pharmacologic and nonpharmacologic (eg, exercise, remaining active) therapy.
- If there are persistent or progressive symptoms during or following 6 weeks of conservative management and the patient is a surgery or intervention candidate or diagnostic uncertainty remains, MRI of the lumbar spine has become the initial imaging modality of choice in evaluating complicated low back pain.
- MRI is the imaging procedure of choice in patients suspected of cord compression or spinal cord injury.
- Patients with recurrent low back pain and history of prior surgical intervention should be evaluated with contrast-enhanced MRI.
Sherman Tran MD
Founder and President, Spine & Sports Medical Group