When is an MRI most reliable for a soft tissue running injury? Well, that’s what we’re talking about today on the Doc On The Run Podcast.
One of the most important things about getting an MRI, if you have a thing like a ligament injury, a plantar plate sprain, a partial tear of the planter fascia, an Achilles tendon partial rupture, Achilles tendinosis, perineal tendinitis, anything that’s a soft tissue injury, the timing of the MRI is extremely important. MRIs are really interesting, really useful tools and when you get an MRI, you have over a hundred pictures of your foot and because you have so many pictures that look so impressive, you can actually fool yourself into believing that it’s a complete picture, and it is it not.
It is a snapshot in time with very particular locations of pictures, not the entire foot, it just looks like the whole foot, but each one is an individual slice that gives you a snapshot of that particular spot at that moment in time. The MRI basically shows inflammation as water content, so it looks really bright on a certain set of images, and that’s really how we’re making this diagnosis.
There was an interesting study by a guy named Matt Rocket, who’s a podiatrist in Houston, and I think it was somewhere around 1999 or 2000 or so where he did a study on MRI and the reliability of MRI versus ultrasound studies in soft tissue injuries, like tendon and ligament injuries around the foot and ankle. And what they found was that the MRI missed the majority of the tendon tears. It wasn’t sensitive in the majority of cases where ultrasound was 100% sensitive, ultrasound never missed a tear in those tendon and ligament injuries because they did MRIs and ultrasound on the patients. And then when they took them to surgery, looked to see if there was actually a tear in there.
There was also an interesting study on marathon runners and ultra marathoners in the Trans Europe Foot Race that showed inflammation on MRIs, waxes and wanes, and comes and goes throughout not just the course of your training, but also even through the course of a long, long endurance race. So the timing matters. What is interesting with the soft tissue injuries is that part of the reason that I was saying that the water content is so important on the MRI is that when you have an injury that happens and you have inflammation showing up on the MRI, you have more water in the tendon or the ligament because it’s inflamed and irritated. But when you get chronic problems like where it turns into Achilles tendinosis or planter fasciosis, and you don’t really have that much actual inflammation going on anymore, the structure is damaged, but it’s not showing up as easily on the MRI because it doesn’t have as much water content because the inflammation process is not as active as when it first started.
So if you have a suspected tendon or ligament tear, MRI can be more useful in the phases in the first week or so after those injuries. But if it’s been months, it actually might not help you at all. In fact, it might lead you down the wrong path thinking it’s not really injured when it actually is. So hopefully that’ll help you have a better discussion with your doctor about your particular injury, and you need to think about how soon it’s been or how long it’s been if your doctor’s trying to send you for an MRI to get a better look at it because it might not be that helpful. So I’ll try to put the references in the show notes at docontherun.com on the podcast tab with the show notes for this particular episode. But I hope you found this useful if you have a soft tissue injury and you’re thinking about getting an MRI.
If you like this episode, please like it, please share it, and I’ll see you in the next training.