Why Early Imaging for Low Back Pain is Such a Low Value Service

This issue is “near and dear” because I am a physical therapy (PT) student and a large portion of patients come to PT for lower back pain (LBP). Truthfully, this issue is near and dear to all of us because ¼ of adults in the United States have reported having low back pain in the last 3 months (Flynn). Imaging is important to me because patients regularly come to me with questions and fears about what their MRI showed. Much of my job is spent treating, encouraging and educating patients with LBP.

The American Physical Therapy Association clinical guidelines recommend assuring patients of the relatively favorable prognosis for LBP: 50% of disk herniation and radiculopathy cases improve within the first 30 days (Webster). The APTA also recommends avoiding increasing a patient’s fear or anxiety about their pain. It is important to increase or maintain the patient’s activity level, and encouraging return to work and leisure activities even before the pain has resolved. Much of my job as a PT is encouraging people to stay active, and teaching people to move in ways that “nudge” but don’t overly provoke the pain.

Medical imaging, within the first 6 weeks of LBP onset, is not recommended for lower back pain that exists without the presence of “red flags.” This use of imaging is a low-value service according to the VCHI 2016 Virginia Low-Value Service Report (soon to be released). Imaging for acute LBP costs a significant amount of money, and it is lacking in benefit.  The cost of treatment of LBP in the United States is already huge and continues to grow year by year (Rivero-Arias).

A little more explanation of this low-value service: “red flags” are possible indicators of serious spinal pathology, such as cauda equina syndrome (where the end of the spinal cord is tethered to the base of the spinal column), fracture, cancer, and an infection. Some of these are red flags that various clinical guidelines recommend screening for:

  • Thoracic pain
  • Fever
  • Unexplained weight loss
  • Bladder or bowel dysfunction
  • History of cancer
  • Progressive neurological deficit
  • Night pain, or pain that is not relieved by rest
  • Disturbed gait, saddle anesthesia
  • Age of onset <20 years or >55 years
  • History of a trauma, which may indicate fracture

(Verhaugen)

Cancer, fracture, infection, and cauda equina are very rare. Each of these occurs in less than 1% of patients with LBP. Interestingly, at least one “red flags” is present in 80% of people who present to physical therapy for LBP. When red flags are present, and unexplained by other issues, however, it is very important to discover if one of these previously mentioned issues are behind it. These are important to discover because early treatment can make a large difference.

If a patient demonstrates a reason for further testing and diagnostic imaging, it is important to recognize it and refer to the appropriate practitioner. If a patient demonstrates no signs of serious pathology, however, medical imaging is not necessary within the first 6 weeks of onset. If LBP has not resolved or significantly decreased in 6 weeks of conservative treatment, it is likely that there is something more going on, and imaging is indicated.

It’s counter-intuitive that a simple MRI or CT scan can cause damage to a patient, but unnecessary imaging has been found to increase cost and even result in worse outcomes for patients and delayed return to work. (Webster)

The reasons that early medical imaging may be harmful:

  1. MRIs often reveal pathology that is unrelated to the patient’s pain or limitation (normal signs of aging for example): Disk herniation and/or spinal stenosis can be found in 20%-57% of NON-symptomatic individuals. In other words, an MRI can reveal pathology in someone who has no symptoms at all.
  2. A picture showing a bulging disk can be a powerful thing for a patient to see and cause them to be more fearful, hyper-focus on their pain, and avoid physical activity:  This is harmful, because up to 50% of disk herniation and radiculopathy cases resolve in the first month. Early movement and physical activity are absolutely essential for recovering from LBP. Early MRIs result in a later return to work according to an article concerning workers compensation cases (Webster).
  3. Increased cost for the same, possibly inferior, results: Early MRI (within the first 30 days of onset) can increase cost for a patient by $12,948 to $13,816 over the first year of care. Even in a relatively “minimal disability” subgroup, costs were $7,643 to $8,584 higher on average for those who received an early MRI. (Webster). The numbers vary from source to source, but most agree that patients who receive early imaging pay more than those that do not.

(Flynn)

Despite this, ordering for early MRIs has increased 2-3 X from 2001-2011 (Flynn).  What can be done to reduce the use of imaging by health care professionals? One systematic review found that clinical decision support, such as a modified referral form, reduced imaging by 36.8% in the hospital setting. Targeted reminders to primary care physicians decreased imaging by 22.5%. These reminders were concerning the appropriate indications for imaging referrals (Jenkins). In other words: education and consistent reminders are effective ways to adjust behavior.

Reducing low-value care, and increasing high-value care, are both key to improving the efficiency of our health care system. Improved efficiency means less cost, and better results for our patients.

Sources


Flynn, Timothy W, Britt Smith, and Roger Chou. “Appropriate Use of Diagnostic Imaging in Low Back Pain: A Reminder That Unnecessary Imaging May Do as Much Harm as Good.” The Journal of Orthopaedic and Sports Physical Therapy 41, no. 11 (2011): 838-46.

Jenkins, Hancock, French, Maher, Engel, and Magnussen. “Effectiveness of Interventions Designed to Reduce the Use of Imaging for Low-back Pain: A Systematic Review.” Canadian Medical Association Journal187, no. 6 (2015): 401-08.

Rivero-Arias, O., Campbell, Gray, Fairbank, Frost, and Wilson-Macdonald. “Surgical Stabilisation of the Spine Compared with a Programme of Intensive Rehabilitation for the Management of Patients with Chronic Low Back Pain: Cost Utility Analysis Based on a Randomised Controlled Trial.” BMJ 330, no. 7502 (2005): 1239.

Verhagen, Arianne, Aron Downie, Nahid Popal, Chris Maher, and Bart Koes. “Red Flags Presented in Current Low Back Pain Guidelines: A Review.” European Spine Journal 25, no. 9 (2016): 2788-802.

Webster, Barbara S., Ann Z. Bauer, YoonSun Choi, Manuel Cifuentes, and Glenn Pransky. “Iatrogenic Consequences of Early Magnetic Resonance Imaging in Acute, Work-Related, Disabling Low Back Pain.” Spine 38, no. 22 (2013): 1939-946.