When to ignore your MRI results

I can't tell you how many times a patient has come to my office and told me "My doctor ordered an MRI and I have a disc bulge at so-and-so level, so that's where my pain is coming from." Or they say "I had an MRI years ago and it showed disc degeneration at L4/L5 so I know my back will never really be fixed." However, when I perform an examination I very often find that the disc is not the cause of their pain. When I try to explain this to them they're usually nonplussed.

In my opinion we need to stop taking so many MRIs on patients with back pain. Why? For the vast majority of low back pain cases MRIs do more harm than good. "How is that possible?” you might ask, "Don't you want as much information as you can get?"

While diagnostic studies like MRI can be helpful in making a diagnosis, they need to be placed in context with the rest of the clinical picture. A detailed history and physical examination are extremely important in determining the cause of a patient's pain and often reveal that the MRI findings are not clinically relevant.

Consider for instance a New England Journal of Medicine study entitled “Magnetic resonance imaging of the lumbar spine in people without back pain” which took MRIs on 98 asymptomatic people and found that “52 percent of the subjects had a bulge at at least one level.” In fact, this study concluded “On MRI examination of the lumbar spine, many people without back pain have disk bulges or protrusions but not extrusions. Given the high prevalence of these findings and of back pain, the discovery by MRI of bulges or protrusions in people with low back pain may frequently be coincidental.”

An earlier study was performed on sixty-seven individuals who had never had low-back pain or sciatica in their lives. Disc degeneration or bulging was found on MRI in 35 per cent of the subjects under the age of 40 and disc degeneration or bulging was present in all but one of the sixty to eighty-year-old subjects. In a more recent study, MRIs were taken on 1043 volunteers between 18 to 55 years of age. Forty percent of the individuals under age 30 had lumbar disc degeneration and over 90% of the individuals 50 to 55 years of age had lumbar disc degeneration. In other words, lumbar disc degeneration and disc herniations are extremely common, even in patients who have never had back pain.

So what’s the big deal? Why not get an MRI anyway?

First of all, even when examination findings do support the diagnosis of disc herniation, MRIs do not improve patient outcomes. A study published in the journal Lancet demonstrated that X-rays and MRI for low-back pain do not improve clinical outcomes. And, a study in the Journal of Bone and Joint Surgery indicated that "findings on magnetic resonance scans were not predictive of the development or duration of low-back pain. Individuals with the longest duration of low-back pain did not have the greatest degree of anatomical abnormality..."

Second, I believe that a positive MRI finding often leads to a pattern of learned helplessness wherein these patients believe that their backs are “broken”. I think this might be the reason that patients receiving MRI in the Lancet study actually responded marginally WORSE to treatment than patients who didn’t get MRI. Patients who have a disc herniation that shows up on MRI often think that there’s no hope for them living a life free from low back pain. These patients come to believe that they “just have a bad back” and they can’t do anything about their “bulging discs” unless they have surgery. These patients need to understand that almost everyone eventually develops some degree of degenerative disc disease and yet most people are not living a life of pain. Doctors need to empower these patients to improve their overall health, work on their flexibility, and improve their core strength.

Lastly, in my experience doctors often focus far too much on MRI results. Disc herniations often become a “red herring” wherein doctors place such importance on the MRI results that they miss the real cause of a patient’s pain. Doctors often overlook common causes of back and leg pain such as: pseudosciatica from myofascial pain in the gluteus minimus, low back pain referred from the iliopsoias, or lumbar facet syndrome. A thorough examination that includes range of motion, standard orthopedic tests, and (most importantly) detailed palpation of spine and deep hip musculature is critical in determining the cause of a patient’s pain. When the specific structures causing the pain are identified, an appropriate treatment plan along with patient education can be very effective.

I genuinely believe that patient outcomes can be significantly improved if doctors ordered fewer MRIs and spent a little more time performing a thorough examination. Therefore, I agree with guidelines outlined in the Annals of Internal Medicine which recommend that for adults less than 50 years of age with no red flags for serious spinal pathology, no X-rays or MRI is necessary. For patients over age 50, X-rays and simple laboratory tests can almost completely rule out underlying systemic diseases. And finally, MRIs should be reserved for patients who are considering surgery or those in whom systemic disease is strongly suspected.