Today on the Doc On The Run Podcast we’re talking about thinning of the plantar plate ligament on an MRI in a runner.
In this episode we’re talking about the plantar plate ligament, and most specifically about what it means if you’re a runner and you have what is known as thinning of the plantar plate ligament when you get an MRI report. So this is one of the things I frequently get from runners when they call me for a second opinion, we do a telemedicine visit, and then I look at their MRI.
What they’re usually concerned about is this thing that the radiologist mentioned which is thinning of the plantar plate ligament. I was doing a telemedicine call just a couple of days ago with someone and that was his big question. He said, “What does this really mean? Do I really have a tear? Is it a problem? Will I be able to continue to run?” What is the issue with this idea of thinning of the plantar plate ligament, and why does it happen?
All right, as you know, the plantar plate ligament is a band of tissue made mostly of collagen that is adhered or stuck on the bottom of the joint capsule, and it usually gets inflamed and runners when they start having pain at the base of the second toe and the ball of the foot.
And the thinning of the plantar plate ligament usually happens for one specific reason in runners, and that is because you start getting pain and injury to the plantar plate ligament, or the joint capsule, at the base of the second toe where it attaches to your foot, and you ignore it, you continue to run on it, it continues to stay inflamed, you don’t do anything to reduce the pressure, stress, inflammation, or anything in that area, and it stays chronically inflamed.
Well we know that chronic inflammation in a joint is a bad thing for several reasons. One of the reasons is that the inflammatory fluid has degradative enzymes that break up collagen, and they’re not just inherently bad. I mean, if you have a tissue injury and you tear something, you rip something, you have little bits of collagen debris where you’ve injured a structure, you can’t repair it until you get the garbage out. And the degradative enzymes are just supposed to dissolve those little bits of tissue debris so your bloodstream can carry them away. That’s part of the cleanup process that has to start before you get the repair process.
But when you have pain that you continue to ignore, when you have this aching pain in the ball of the foot, at the base of the second toe, and you have what’s been diagnosed as capsulitis or a plantar plate injury, a plantar plate sprain, any of those things, that chronic inflammation actually makes all of the structures in that area weaker and potentially thinner. They can actually atrophy or wither away a little bit.
And so when I see runners who’ve had an MRI, and they don’t have a distinct tear of the plantar ligament, there’s not an obvious rupture of the plantar plate ligament, but the radiologist mentions that they have some thinning of the plantar plate ligament, what that really means is that the chronic inflammation has actually caused some of the collagen to dissolve, and so it’s actually getting thinner, now that obviously can make it weaker. And it’s very rare when you get an MRI report from the radiologist that says you only have thinning of the plantar plate ligament.
There’s usually another couple of things that go right along with that, one of them is inflammation within the joint capsule. So the radiologist may say something like, signal change noted with intensity that signifies edema within the planter joint capsule, or the entire second metatarsal phalangeal joint capsule.
There are a lot of different terms they can use, but basically you have inflammation in that whole area. And as a consequence, you don’t just get thinning of the plantar plate ligament, you’ll often get thinning of other structures that are nearby, like the collateral ligaments. And that is a really common finding, and it doesn’t mean that everything is necessarily injured, but it’s kind of getting injured from the chronic inflammation.
So for that reason, if you get an MRI and you think you have a tear of the plantar plate ligament, but the radiologist only mentions that you have thinning and chronic inflammatory changes within the joint, that’s actually better in a way.
So you can’t really fix it necessarily in terms of making it thicker right away, but you can stop the damage process, and that means stopping the inflammation and stopping the chronic irritation that is actually causing that inflammation to happen. So you have to do something to reduce inflammation, you have to reduce the stress and strain on the plantar plate ligament, and make sure that you just don’t continue to make it worse.
So that’s part of what we talk about in the Plantar Plate Sprain Course for runners, we talk about all the different causes of stress and strain on the plantar plate ligaments, how you can reduce the stress and strain on the plantar plate ligament. But you’ve got to go about addressing the root cause of the problem. That is two things, number one, the inflammation, and number two, the stress that’s actually behind all of that inflammation.
But don’t freak out if you get an MRI and it says you have a little bit of thinning, that’s better than some of the other things you could see. It’s way worse if you have an actual tear or a rupture of the plantar plate ligament. The thinning just means that it’s getting thinner over time because you have inflammation that keeps happening over and over and over. So make sure you address that inflammation and you’ll be back to running in no time.
Remember, it’s not really that complicated. When you have a plantar plate sprain and you want to get back to running, you need to confirm you have the right diagnosis.
You need to decrease some stress and strain to the plantar plate ligament, decrease the inflammation around the joint and then follow a very structured return to running that will allow you to retain your aerobic fitness, rebuild your running fitness and prevent you from getting another overtraining injury.
But if you do that, you can heal the plantar plate ligament and keep running!