Imaging: Significant finding or normal ‘Wear & Tear’?
How can an image lie? Because images are interpreted by a radiologist to produce a summary of what they see and don’t see. While this process is meant to be as objective as possible, there is still room for interpreter bias.
On this edition, I’m excited to discuss another topic of conversation I frequently discuss. Radiographs (X-rays) and Magnetic Resonance Imaging (MRI’s) are very commonly used to get a better understanding as to what may be causing pain and/or dysfunction. When combined with a clinical or functional diagnosis, the use of imaging can be very reliable and paint a very accurate picture to help explain the problem in question.
However, a clinical diagnosis is <usually> missing when determining best course of treatment. Unfortunately, our current healthcare system dictates that our Physicians see roughly 50-60 patients each day. This means they only have roughly 5-7 minutes to perform a complete examination, interpret the results of imaging, determine the best course of treatment, and discuss this with the patient for their consent. At no fault of their own, this system does not allow them to fully evaluate the patient at a functional level. They must rely primarily on the findings of imaging to determine the next steps. Often times, this can lead to unnecessary interventions, such as surgery and injections, that don’t work or leave a matter of the problem left unresolved.
‘But if a doctor sees arthritis on my X-ray, isn’t that obviously the reason for my knee pain?’
The short answer: possibly! But not guaranteed. Why is this? What we often forget to consider is what’s considered ‘normal wear and tear’, and what is pathological. In a 2014 study published by Brinjikji et al., they looked at Lumbar MRI’s of 3,110 asymptomatic patients across 33 different studies, meaning these patients had no history of low back pain. What they found is that 37% of 20-year-old individuals displayed signs of degenerative discs (aka ‘Arthritis’ of the spine), increasing to 96% of 80-year-old individuals.
What about something more serious like bulging or herniated discs? That can’t possibly be ‘normal’…
In fact, it is. They found 30% of 20-year-olds showed disc bulging increasing to 84% of 80-year-olds and protruding discs in 29% of 20-year-olds and 43% of those in their 80’s.
The only possible way to accurately conclude that these findings are the sole contributor of pain and dysfunction is to perform an MRI immediately before the onset of pain and then again immediately after the onset of pain and compare the difference. Though, this is obviously not feasible. Even still, there could be minor changes that are not detected on the image that explain the onset of pain.
But imaging doesn’t lie, does it?
It does, sometimes. In another study by Herzog et al. In 2017, they asked a 63-year-old female to receive an MRI at ten different MRI centers over a 3 week span. This lady did have a history of low back pain and shooting pains down the leg. Across the 49 distinct findings amongst all 10 of the MRI’s, there were NO findings that were reported in all ten reports. One finding was reported in 9/10 MRI’s and 32.7% of the findings were only reported once. Let that sink in…
How can an image lie?
Because images are interpreted by a radiologist to produce a summary of what they see and don’t see. Some radiologists consider certain findings ‘normal’ and some don’t, some may miss something others see, and sometimes the image is blurry and difficult to accurately assess. While this process is meant to be as objective as possible, there is still room for interpreter bias.
However, imaging is absolutely necessary sometimes and I do not mean to take away from it’s importance in diagnosis and treatment. It certainly helps us paint a complete picture, especially when there is such intense pain that a full functional exam is not appropriate.
This edition simply aims to help educate the general population about the use of imaging and to always take the findings of an image with a grain of salt, or two, and using the results of an image combined with a functional exam can help you decide the best course of treatment.
If you have any questions, don’t hesitate to ask! Grant@advancedmanualtherapies.com
Thanks for reading!
-Dr. Grant