Diagnostic imaging such as MRI or CT is indicated for patients with low back pain only if they have severe progressive neurological deficits or signs or symptoms that suggest a serious underlying condition. Such as cancer, fracture or infection. Of the small proportion of patients with any of these conditions, almost all have an identifiable risk factor.
About 0.7% of patients presenting to primary care with low back pain have metastatic cancer, 4% have vertebral fractures and 0.01% have a spinal infection.
Both healthcare professionals and members of the public often consider getting a scan “just in case”. However, all the evidence suggests scans only show something truly important in a tiny minority of people with back pain. A brief consultation with a healthcare professional would usually be able to identify if a scan was really needed based on a person’s symptoms and medical history.
We used to think that if we got a good enough picture of the spine with scans that it would be a big help in solving the patients back pain. However, we now know that this is most often not the case. When people have scans for back pain, the scans often show up things that are poorly linked with pain.
Remember, these people do NOT have pain!
Unfortunately, people with back pain are often told that these things indicate their back is damaged, and this can lead to further fear, distress and avoidance of activity. The fact is that many of these things reported on scans are more like baldness or wrinkles – an indication of ageing and genetics that do not have to be painful.
These things sound scary and we are taught to think that they are very important for pain. But the simple truth is that they are often TOTALLY IRRELEVANT. No one tells you that EVERYONE has these changes in their body. What we have been calling abnormalities are really just normalities.