As physiotherapists we are often confronted with two important questions from patients about MRI scans (Magnetic Resonance Imaging). One is from patients who want an MRI and want to know why their doctor won’t refer them and the other is from patients who have had an MRI and been told they have degenerative changes but not to worry about it.
For the first patient who wants a scan, the important question to ask is “will a scan change your treatment?” and in the early stages of a condition it is likely that the answer to that question is no.
In the second scenario the important question to ask is “what is a normal finding on an MRI?” and the answer might surprise you.
The reasons for the answers to the above questions become more apparent when you look at the research into healthy people. For example, if you are suffering with low back pain you might think that an MRI scan would explain your symptoms, but a study by Brinjikji et al. (2014) shows no consistent association of MRI findings of spinal degeneration and low back pain. Brinjikji et al. (2014) found that 37% of 20-29 year olds without any low back pain had disc degeneration and this only increased with age. Similarly, degenerative (arthritic) joints were seen in a healthy population without low back pain. More details can be seen in the table below.
As we age, some of us will lose our hair, others will go grey and some will get more wrinkles; all classic signs of ageing. We all get older on the inside as well, so some of these findings on scan will be as normal as a thinning hair line and not something to worry about. Similar findings are reported by Gill et al. (2014) for shoulders and by Guermazi et al. (2012) for knees.
If your symptoms persist and physiotherapy does not help it may be appropriate for you to have an MRI or similar investigation. Under normal circumstances your GP would refer you to a consultant doctor who would then make that decision, but unless surgery is a realistic possibility it is not advisable to have an MRI. For anyone that does have an MRI, expect there to be something found on scan but remember that this may have nothing to do with your symptoms and you may well be referred back to physiotherapy for further treatment.
Brinjikji, W., Luetmer, P.H., Comstock, B. et al. (2015). Systematic literature review of imaging features of spinal degeneration in asymptomatic populations. American Journal of Neuroradiology, 36(4), pp.811-816. http://www.ajnr.org/content/early/2014/11/27/ajnr.A4173.full.pdf
Gill, T.K., Shanahan, E.M., Allison, D. et al. (2014). Prevalence of abnormalities on shoulder MRI in symptomatic and asymptomatic older adults. International Journal of Rheumatic Diseases, 17(8), pp.863-871.
Guermazi, A., Niu, J., Hayashi, D. et al. (2012). Prevalence of abnormalities in knees detected by MRI in adults without knee osteoarthritis: population based observational study (Framingham Osteoarthritis Study).