X-rays and MRIs for Acute Low Back Pain: Not So Fast

spine exam
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Low back pain is among the most common reasons for people to seek medical advice. In the United States, low back pain is the number two reason why people make a doctor's appointment, only surpassed by upper respiratory infections. Low back pain is incredibly common, and just about everyone can expect to have an episode (if not multiple episodes) of back pain at some point in their lifetime.

When evaluating low back pain, your clinician will take special care to ensure that there are not signs or symptoms of a more worrisome problem.

 Because of the nature of back pain, people are often worried that something is seriously wrong in their spine. Most people have not experienced this type of pain before, and this can cause concern for the possibility of a serious condition or a problem that may progressively worsen. Back pain symptoms are often very different than typical symptoms of a sprain, strain, or contusion. People may describe a deep aching sensation that is hard to relieve. The unusual nature of this discomfort can make people think that a serious condition exists within their spine.

Those affected with low back pain are worried they might have something serious such as a tumor or infection, or a condition that is not going to get better and will eventually lead to a crippling disorder. The reality is that this is seldom the case, despite the severity of symptoms. That said, it is a concern for many people and therefore patients often wonder if radiographic imaging such as x-rays or MRIs might be helpful in their evaluation.

It is not unusual for someone with acute low back pain to come together Dr. expecting to have an MRI test to evaluate their condition.

The Recommendations

The reality is that radiographic imaging is seldom beneficial in the early stages of evaluation of low back pain. In fact, numerous professional societies including the North American Spine Society and the American College of Physicians, have given specific recommendations that imaging studies should not be obtained in the early stages of typical low back pain.

There are reasons why imaging may be helpful, but these are typically the exception rather than the rule. In the medical world, physicians often use the terminology "red flag" symptoms. These are symptoms that may be signs of a more serious condition such as:

  • Tumors
  • Infection
  • Fracture
  • Severe neurologic compromise

If symptoms of these conditions are present, imaging studies may be helpful. Symptoms of these conditions might include fever, recent weight loss, history of cancer, history of intravenous drug use, history of severe trauma, urinary retention or incontinence, or other signs. Again, these signs are infrequently present, but when these "red flag" signs are present a further evaluation may be necessary.

The recommendations are not vague; in fact they are quite clear. The North American Spine Society specifically states to physicians: "Don’t recommend advanced imaging (e.g., MRI) of the spine within the first six weeks in patients with non-specific acute low back pain in the absence of red flags." The American College of Emergency Physicians tells physicians: "Avoid lumbar spine imaging in the emergency department for adults with non-traumatic back pain unless the patient has severe or progressive neurologic deficits or is suspected of having a serious underlying condition." The American College of Family Physicians statement reads: "Don’t do imaging for low back pain within the first six weeks, unless red flags are present."

Rationale From Recommendations

The reason these professional societies make these recommendations so clear is, ultimately, that the imaging studies do not provide value in terms of helping patients find relief from their discomfort. The treatment of acute low back pain does not change based on x-ray and MRI results. Even if the underlying diagnosis is not entirely clear, the treatment recommendations are not altered. As a general rule of thumb, a test is obtained when the results of that test are likely to lead to one of two (or more) different treatment paths. If the result of the test is unlikely to change the treatment path, then generally the test should not be performed.

In this case, imaging studies do not change the treatment recommendations for typical acute low back pain.

In addition, sometimes imaging studies can complicate the situation. An imaging test may lead to unnecessary invasive procedures or additional tests, and further testing may not ultimately help relieve symptoms. The treatment of acute low back pain should be focused on efforts to relieve symptoms including gentle movements and activity, avoidance of aggravating activities, as well as specific therapies that may provide relief including:

Each of these treatment modalities has been shown to provide pain relief in the setting of acute low back pain. In addition to avoiding imaging, similar recommendations have advised avoiding prescription medications, specifically narcotic medications for the treatment of back pain. When medications are used, they should typically consist of over-the-counter medications including nonsteroidal anti-inflammatory medications and/or Tylenol.

A Word From Verywell

Low back pain can be a frightening experience, especially when it seemingly comes out of nowhere. People find the pain is unusual, uncomfortable, and frightening. For these reasons, many individuals with low back pain wonder if imaging tests may be necessary to evaluate their spine. The reality is, except in specific circumstances, imaging of the spine with x-rays, MRIs, or other tests is typically not necessary. In fact, numerous professional societies have made specific recommendations that patients should avoid these types of imaging tests. While they may ultimately become necessary, the vast majority of people with low back pain will never require imaging to help relieve their symptoms.


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Chou R, et al. Clinical Efficacy Assessment Subcommittee of the American College of Physicians; American College of Physicians; American Pain Society Low Back Pain Guidelines Panel. "Diagnosis and treatment of low back pain: a joint clinical practice guideline from the American College of Physicians and the American Pain Society." Ann Intern Med. 2007 Oct 2;147(7):478-91.

Forseen S, Corey A. "Clinical decision support and acute low back pain: evidence-based order sets". J Am Coll Radiol. 2012 Oct;9(10):704-12.