Is an MRI Really Needed When You Have Back Pain?

Everyone has a duty to help reduce health care costs. In this article, physiotherapists step up to bat with one idea: determine when advanced imaging is really needed. They start by looking at a patient population group that is very common in a physiotherapyclinic: people with low back pain.

It's estimated that half of all patients seeing physiotherapists in outpatient clinics have come for one thing and one thing only: low back pain. With direct access (patients can see a physiotherapist without seeing a physician first), therapists need to know when patients should have X-rays and/or other imaging studies. Likewise, the physiotherapist must be able to decide when such diagnostic aids are not needed.

Many studies have shown that findings of degenerative disease, malalignment of the spine, and other anatomic problems or deformities don't always cause symptoms. And the opposite is true, too -- patients with severe pain may have very normal looking X-ray, CT scan, or MRI results. Successful, evidence-based treatment may not depend on imaging results.

In fact, sometimes patients who see the changes on imaging studies (or who are told about them) end up worse off. Their perception of health deteriorates. They start avoiding certain activities or movements that "might cause pain." The end-result is worse pain and decreased function. Not only that but the rates of surgery have increased two to three times what they were 10 years ago.

So, when should X-rays or other diagnostic imaging be done with low back pain patients? According to the American College of Physicians and the American Pain Society there are three basic guidelines. First, don't order X-rays or other imaging studies routinely.

Second, don't order diagnostic imaging studies unless there are strong clinical signs that surgery or steroid injectins may be needed. And third, use imaging studies when there are severe neurologic signs and symptoms that could result in permanent neurologic damage (including permanent loss of strength, sensation, or even paralysis).

These guidelines were first published in 2007 and remain appropriate today. They were based on numerous quality randomized clinical trials. Despite these evidence-based recommendations, studies show that one-third to one-half of all referrals for advanced imaging are inappropriate.

Additionally, exposure to radiation is recognized as an important concern now that we have the means to measure the risk of cancer from radiation. For example, one X-ray of the lumbar spine exposes the human body to the same dose you would receive from background radiation over a six-month period of time. And one lumbar spine X-ray is equal to 75 chest X-rays.

In summary, there is agreement among experts who have studied the use of imaging studies that most patients with low back pain don't need X-rays, CT scans, or MRIs. Those who would benefit from imaging can be discerned on the basis of history and physical examination. The biggest concern is for tumors, infection, and fractures.

Physiotherapistsknow how to screen patients for these kinds of problems and what to look for that might suggest a higher likelihood of serious problems. Anyone with low back pain can be confident that seeing a physiotherapist first will save them money in the long-run. The therapist also monitors patients over a period of time and can see changes (or lack of change) to help assist in the decision-making process.

With evidence-based testing, the therapist will know who needs to see a physician and who can benefit from physiotherapy intervention. Studies within the field of physiotherapyhave also provided evidence to help the therapist know the best approach to different types of low back pain. It's a fact that many, many people with back pain and "positive" X-rays showing disc or other spine degeneration recover fully from their painful symptoms even when the X-ray doesn't change.

Future studies will continue to provide information that will help people with low back pain understand the role of self-care, get the right kind of treatment when needed, and save money in the process. Staying active, engaging in movement of all kinds, stretching, and maintaining flexibility are all valuable ways to maintain good spine health and an active, pain free lifestyle.

Reference: Timothy W. Flynn, PT, PhD, et al. Appropriate Use of Diagnostic Imaging in Low Back Pain: A Reminder That Unnecessary Imaging May Do As Much Harm As Good. In The Journal of Orthopaedic and Sports Physical Therapy. November 2011. Vol. 41. No. 11. Pp. 838-846.

Northern Hills Sport Physiotherapy provides services for physiotherapy in Calgary.