This is a question I am asked on a regular basis in my practice as a physiotherapist. The answer is not always so simple! There are many positives but also many negatives to having further investigations such as MRI scans or CT scans in the presence of lower back pain. We often assume that having more information could only be of positive benefit, but here are some facts from recent research that might change your mind:
68% of people over the age of 40 have signs of disc degeneration on MRI
50% of people over the age of 40 have evidence of a disc bulge on MRI
80% of people over the age of 50 have signs of disc degeneration on MRI
32% of people over the age of 50 have facet joint degeneration on MRI
So what does this information mean?
Simply this- most people as we get older will show some signs of wear and tear in either our spinal joints or our spinal discs. In fact this is a normal process. This is not always linked to pain! There are many people with scans that show severe degeneration in their joints or discs who are completely pain free. There have been studies that have looked at the MRI scans of pain free individuals, only to show are large percentage of them have age related changes (disc bulges, joint degeneration, facet joint wear) and yet still remain pain free.
At the other end of the scale, there are plenty of individuals out there who are experiencing a lot of pain, yet whose scans show absolutely no changes on MRI and are reported to be in perfect spinal health. We can conclude that what is reported on your scan certainly does not seem to influence or correlate with pain.
So if you have an MRI that shows a ‘disc bulge’, it might not actually be the problem that is contributing to your pain. It might in fact just be a normal scan showing some wear and tear, exactly the same as anyone else your age. The MRI scan needs to be looked at and matched to all of the other presenting signs and symptoms you have, and this is best done by a health professional such as a physiotherapist.
I have had plenty of patients who have had a disc bulge evident on an MRI scan, and once I have completed my physical assessment it is clear that a simple answer like a tight hip is the cause of their problems. Meaning we can happily ignore the MRI, progress with some exercise and postural advice and resolve the problem.
Research is also now supporting the fact that sometimes having an MRI scan can actually be detrimental to your recovery. A recent study in the UK discovered that when individuals with acute back pain (less than 6 weeks) were divided into two groups with one group having an MRI and the other without, the outcome was not so positive. The group that had the MRI scans reported pain for a longer period of time and spent more money on therapy to recover than the group that did not have MRI scans.There are many reasons for this negative effect of having an MRI, but one may be the introduction of fear and fear avoidance behavior. I will discuss this topic in my next blog!
So do you need an MRI? Is it still relevant to have an MRI? This needs to be assessed by your health professional. The reasons I would consider referring for an MRI would include if I considered that the patient needed more urgent medical intervention (such as injections) or surgical intervention. I would refer if the patient demonstrated signs or symptoms of pathology that might need intervention outside the realm of physiotherapy, such as with tumors or growths. There are still many reasons that I would consider a referral to a specialist for an MRI or CT.
All of these factors need to be considered when referring for further investigation, and this information might explain why sometimes physiotherapists advise that it’s not always essential for you to have a scan!