Physicians know that X-rays, CT scans, and MRIs don’t really contain the rest of the story. Many patients have all kinds of changes in the lumbar spine but no symptoms — no pain, no change in sensation. There can be narrowing of the disc spaces, spinal stenosis (narrowing of the spinal canal), spinal joint arthritis, and even tiny fractures called spondylolysis but no one knows about it until X-rays or other imaging studies are done for something else.
Most of the folks who have what looks like significant changes of this type in the spine are older adults (65 years old and older). Low back pain can be a common symptom in this age group. So, how much of these changes (and which ones) are linked with back pain? That’s been the focus of many researchers for quite some time.
A recent study from Boston University School of Medicine looked at the results of CT scans as a diagnostic tool. They found that although the CT scans gave a good look at the finer details of spinal anatomy, only spinal stenosis was really associated with low back pain — and a plain X-ray can show stenosis, so CT scans aren’t needed for routine evaluation.
MRIs are able to detect changes in the water content of the bones, discs, muscles, and other soft tissues. Disc abnormalities are easily viewed with an MRI. But again, many of the degenerative age-related changes observed don’t predict or correlate with back pain. So unless the physician suspects a disc protrusion, tumor, infection, or fracture, the use of more expensive imaging studies such as MRI is not advised.