#624 Cuboid stress fracture fundamentals for runners - DOC

#624 Cuboid stress fracture fundamentals for runners

Today on the Doc on the Run podcast we’re talking about cuboid stress fracture fundamentals for runners.



If you’re a runner and you get an aching pain on the top of the foot and you’re told it’s an ankle sprain, you’re told maybe it’s a foot sprain and it’s not getting better, you might have this weird thing called a cuboid stress fracture. Now, when you look at your foot, the cuboid bone is actually this one that has, of course, the star on it. The cuboid bone is one that can get squished in between some other bones and it can cause a lot of trouble. Because if you ignore it, it can get worse and turn into an actual fracture, or even worse, get crushed completely if it gets weak enough because you ignore it.

The good news, before we really get into all the details, is that the cuboid bone really does have a great blood supply and it’s one of the fastest stress fractures to heal in your foot. So if you do get one and you do something about it, you treat it appropriately, there’s a good chance it’ll go away pretty quickly. That’s the good news.

The bad news. If you ignore a cuboid stress fracture, if you let this thing get worse and worse and worse and more inflamed and more inflamed as you irritate it, as you squish it, as you stress it, as you pull on, as you compress it, well, if you do that, it can get significantly worse. And the increased blood flow in the bone as a consequence of the stress reaction that doesn’t go away, it actually weakens the bone and then it can really break.

This bone is sandwiched in between several others. So if you get a fracture of the cuboid, it can actually cause lots of pain in several different joints and it’s very difficult to fix or make better if you’ve really disrupted the joint surfaces around it after it breaks so you don’t want to do that. Now, that’s the bad news.

Okay, let’s talk about how this works. Well, one of the things is the cuboid bone, because it’s sandwiched between the metatarsals and the heel bone, you can actually compress it a lot and get this thing called a nutcracker fracture. It’s just what the image in your mind says, is you put a nut in a nutcracker and it cracks it and actually breaks it. Now, that usually happens because of trauma, but it can evolve into that if you ignore it and you just keep running on it and stressing on it in a way that makes it worse and worse.

Let’s talk about the details and draw some pictures and stuff that may help you understand a little bit more about this. First thing also I’ll tell you is that, in case you’re wondering about how common these are, first of all, they are not common, they’re very rare. But when you get misdiagnosed with something else, then you treat it inappropriately, it can continue to go on for a long time. So even though they can heal quickly, if you ignore it, they can go on a long time.

Now they’re really common in kids, but they are very rare in adults. So if you’re an adult runner, very unlikely that you actually have one of these, but if you do, it’s better to understand it.

Let’s draw some pictures and talk about what the cuboid is. If we draw your foot and you’ve got the heel bone sitting back here, there’s a part of your heel bone that we call the anterior process of the calcaneus. Then the talus bone sits on top of there, your shin bone and your tibia sits on top of there, and you have the cuboid sitting over here like this.

You have a whole bunch of other bones in your foot that aren’t as important, but what is important is that the fifth metatarsal bone sits here, fourth metatarsal bone sits there and you have all the other metatarsals that line up, but they’re not as important again.

Cuboid bone fracture appearance on X-ray. You can see the jagged white fracture line through the cuboid bone.

We’re talking about the cuboid. The cuboid bone is the one that gets into trouble and the cuboid bone, of course, being here is the one we’re worried about. If it gets stressed, if it gets inflamed, if you get a stress fracture, you’re squishing it, you’re pulling on it, you’re compressing it, you’re doing something to irritate it, it can become a real problem.

Also to tell you exactly how rare they are, if you look at the medical literature and you try to look up cuboid stress fractures, you’ll find probably a study that was published on stress fractures in the feet of soldiers. They looked at 113 different soldiers and they only found one cuboid stress fracture so that’s less than 1% based on that study. (Posinkovic B, Pavlovic M. Stress fractures. Lijec Vjesn 1989;111:228-31)

You also have on the side of the foot, not just these bones. One mechanism is that you can compress them where you’re actually applying pressure in this direction and that directions with the heel bone going this way, the metatarsals going that way in a way that compresses the cuboid and causes stress that can lead to a stress fracture.

But you also have the peroneal tendons, and one of them that really does have the potential to cause some trouble and seem like a stress fracture is the peroneus longus. Now it’s way up in your leg on the back of the fibula and that again is called the peroneus longus because it’s the long one. You have a long one and a short one.

The longus is up there and the longus tendon actually comes down behind the fibula and goes down around the heel bone. There’s a groove on the side of the cuboid and it comes down around that groove and then goes across the bottom of your foot to attach to the base of the first metatarsal bone. But because it actually wraps around the cuboid right here in that area where it wraps around the cuboid, it can actually compress it. So you’ve got, again, the peroneus longus is up here, the tendon comes down behind the fibula bone, and then it actually curves through that little groove in the cuboid and wraps around, goes all the way to the bottom of the foot, but it’s wrapping all the way around the cuboid.

A couple of things that can cause cuboid stress fractures related to that. One of them is that, for example, if you sprain your ankle. You roll your ankle over and you twist your foot like that, it can actually compress the cuboid and lead to a stress fracture. That’s one way.

Also, if you think about this, when you look at your foot, you have three arches. You actually have an arch that goes this way. You have an arch that goes this way, that’s the medial longitudinal arch. Then you have a little one on the outside called the lateral longitudinal arch.

Well, this arch is bigger than this arch so when your foot collapses, it actually pushes to the outside and when you push the foot to the outside, it compresses the cuboid. If you have a really unstable flat foot and you’re pushing the foot to the outside, that can actually compress the cuboid and lead to a stress fracture.

Even if your foot isn’t that unstable, if you have a situation where you’re running on a slope like the road, the road’s curved, it’s sloped, it slopes toward the gutter, and if you’re running along the road, let’s say you’re running on the left side of the road facing traffic, cars are coming toward you, sidewalk is on your left, cars are coming by you on the right. Well, the road’s sloped. What’s happening when you’re standing there is that your left foot is supinated. That decreases the stress and strain on the cuboid where it goes around the bottom of your foot. But if your right foot is on that slope, it’s actually forcibly pronating and it does the opposite. It actually pushes and compresses against the cuboid. That’s one way you can get it.

You can also get it if you have another injury and your peroneus longus is actually over-firing and pulling around the cuboid a lot, it can actually cause this stress fracture in the cuboid.

Now, when we look at this, there’s a couple of things to consider as well. First of all, what are the symptoms? When you think about what is the story that fits with a stress fracture in the cuboid, one of them is that you report to the doctor that it feels like you’ve had an ankle sprain or even the doctor tells you, “I don’t really know. It seems like a foot sprain.” Well, if it’s in that area, if it’s on the top of your foot, in front of your ankle, on the outside, meaning toward the pinky toe, on that side of your foot just below your ankle, could be a cuboid stress fracture.

I just saw someone yesterday who had an injury to the cuboid. She had one of these stress reactions in the cuboid, and when I pushed on the cuboid, it hurt. It did not hurt when I pushed on her peroneal tendon, which helps us discern the difference between those things.

So if you have ankle pain, you have ankle swelling, you’ve rolled your ankle recently, the pain’s not really in your ankle, but it’s in your foot and it continues to bother you and seems sort of like an ankle sprain and won’t go away, could be a stress fracture of the cuboid.

Now the other thing is that if you just have some weird pains, it kind of lingers, you’re still training and it’s not getting better and you’re not getting the right diagnosis, could be something less common like a cuboid stress fracture.

Let’s talk about misdiagnosis. There are a bunch of things that happen when you go see the doctor and they think you have a common thing, but you wind up having something that is not common at all and there are other conditions. So misdiagnosis means we say you have an ankle sprain, but you actually have a stress fracture. Anything that’s different. There are several different things.

Number one is a complete fracture. That is where it’s not just inflamed and irritated, but you have a complete fracture or a crack in the cuboid. Now that can happen lots of ways, but you do not want to confuse those two because the treatment is different. So if you have a crack in the cuboid, you don’t really want to run on it, obviously. You don’t want to make it worse.

The second thing, like I said, this tendon, the peroneus longus, a lot of times the peroneal tendons get injured in runners. So sometimes the doctors will look at you and they’ll say, “Well, your peroneus longus hurts when I push on it right here.” Well, the peroneus brevis and the peroneus longus both run right next to the cuboid. So if the doctor is pushing on it, but it’s compressing your cuboid, they may say that you actually have tendonitis so that’s another one. You could have a real fracture, again, of the cuboid, instead of just a stress reaction or a stress response, you could have a peroneus longus. You could have tendonitis in that peroneus longus tendon that runs around there. They may say that you have that, but it could be a cuboid stress fracture. So if you treat the tendonitis and it’s not getting better, could be a cuboid stress fracture.

Image A: Stress fracture of the cuboid bone shows up as a dark area on MRI, when the other non-injured bones appear white. Sometimes on this set of MRI images (who doctors call “T1” iMRI images) you may find a visible crack in the bone if the stress fracture has continued to worsen.
Image B: The dark boned are normal. Stress fracture in the cuboid shows up as a bright white area where inflammation is occurring inside the cuboid bone.

The next thing is a subluxed cuboid. Subluxed means it’s out of place and we’ll talk about it. I think what I’ll do is I’ll do a completely separate series on how to tell the difference between each of these things and the cuboid stress fracture so that it’ll make this like a one-hour episode or something. But a subluxed cuboid is just where it’s slightly out of position. So if the cuboid moves out of position, then it’s not going to be in the right position. Obviously, it’s going to irritate the neighboring joint, the ligaments, the tendons around it, everything, and it’s going to cause pain so you could have a subluxed cuboid.

The next thing is that you could actually have not an issue with the bone, but you could have an issue where the joint like the calcaneocuboid joint is arthritic, meaning it is just getting destroyed. This is the calcaneus, that’s the medical term for heel bone. This is your cuboid. The calcaneocuboid joint is this joint that is in between the two. So if you have arthritis in the joint, it can get irritated, it can get inflamed, and it can hurt the same way that a cuboid stress fracture does. There’s some differences in the way you can tell and so I’ll do a separate video showing you how to tell the difference between the arthritis and the cuboid stress fracture. But that is another thing you might think about and it’s another thing you could get misdiagnosed with.

Another thing is degeneration of this thing called an os peroneum. What is that? Well, an os peroneum, again, I’ll do a separate video on that, but an os peroneum is a little bone that’s actually embedded in the peroneus longus tendon near that area where it goes around the cuboid and it’s not abnormal. It’s like basically a very, very small version of your kneecap. It works the same kind of way. It’s embedded in the tendon. It has cartilage on it. It should move around the bone. But if it gets damaged, it gets inflamed, it starts to degenerate and the cartilage starts to wear away, it becomes arthritic itself, then it can cause pain. So sometimes if the doctor does an x-ray and they look at you and they see an os peroneum and you have pain near the os peroneum, of course, which is right next to your cuboid, they may say, “Oh, you must have problems, os peroneum arthritis or degeneration of that os peroneum bone and so that’s your problem,” when actually you might have a cuboid stress fracture.

Next thing is that you could have just the ligaments around here. We would call that, to make it a complicated term, let’s call it capsulo, for joint capsule, ligamentous strain. If you get a tendon or a ligament strain or a strain of the joint capsule, it holds all the fluid in the joint and all these little connections here get stretched out, then it can seem just like a cuboid stress fracture and vice versa.

If you go to the doctor and you’ve rolled your foot, let’s say, and you’ve stretched all the ligaments around the cuboid bone where it connects to the calcaneus around the cuboid bone, where it connects to the fourth metatarsal around the cuboid bone, where it connects to the fifth metatarsal bone, when you stretch all that out, when you roll your ankle and you roll your foot under you, then it causes this thing that’s a ligament strain. If the doctor looks at you and pulls on your foot to stretch those ligaments, well, when we do that, unfortunately, we’re actually compressing the cuboid between those bones. So the doctor might look at it and pull on it and tug on it and stress the ligaments, but say, “Well, okay, you have pain when you do that. You rolled your ankle and it went under you. So you probably have capsuloligamentous strain around the calcaneocuboid joint or the metcuboid joint here,” but, in fact, you might actually have a calcaneus stress fracture.

So it could be any of those. Again, what I’ll do is I’ll do a completely separate series of videos that shows you the differences between these things so that you can better understand how to tell each of those apart if your doctor told you that you have one of these and you’re trying to figure out, well, maybe it’s one of these other things.

All right. All that said, the big question, what should a runner do with a stress fracture of the cuboid? Well, you have several options.

Number one, make sure it’s not something else. So if you have a stress fracture of the cuboid or you think you have a stress fracture of the cuboid, you want to figure out could it be one of these other things? Could it be a ligament strain? Could it be the peroneus longus tendon? Could it be the os peroneum or arthritis in the joint, or even worse, a real fracture?

The second thing, obviously, if you think you have a stress-related injury, like a stress fracture to the cuboid, reduce the stress on the cuboid. That’s the biggest thing. The more your foot pronates, again, as your arch collapses and your foot flattened out as you pronate, the more it compresses and stresses the cuboid. So you can do some simple things. One of those is, well, kind of like we talked about before, when you’re thinking about the road. The road is curved. You have the gutter on each side. If you’re standing here, well, your foot is sloped that way. Your other foot is sloped the opposite direction. So if you put the road underneath you to actually supinate your foot, that will help.

If you think you have a cuboid stress fracture because you’ve been running facing traffic and you run in the opposite side of the street, it will reduce the stress and strain on the foot that’s been injured. If you’re running on the road facing traffic and it’s your right foot that is always painful and it’s been painful that area and you’ve been doing a lot of training running that way, if you just switch to the other side of the road, it’s going to do the exact opposite. It’s going to supinate your foot and decrease the stress and strain to the peroneus longus tendon.

If you’re running on flat ground consistently, one of the things you can do, so you think about this, this is the ground. This is your shoe insert inside the shoe and your foot sitting on it. If you take the shoe insert and you actually put a wedge underneath there like this, it actually tilts you over and supinate your foot the same way that the road will supinate your foot. So, literally, adding a wedge on the outside of the insert on the bottom inside your shoe can actually do the same thing. It can actually tilt you over to reduce some of the stress and strain there.

Of course, the other thing you should do is you should check it out. You need to see somebody, you need to get some help, you need to get some support, and you’ve got to try to do something to make sure that you’re not really irritating and aggravating it.

Remember, as long as your foot’s collapsing, you’re stressing the cuboid. As long as that peroneus longus tendon is working hard and being overused maybe to compensate for another injury, it’s pulling and compressing against the cuboid every time it pulls because it wraps all the way around it. If you have this issue and you’re trying to figure out what to do to help, what can you do? Well, you could go see your doctor. That’d be the first thing. So see if you can get in to see your doctor right away.

If you can’t get in to see a doctor right away, you can always do an online consultation with somebody like me or somebody who you know who does online consultations, who you trust, who will help you. You can also even have the doctor who does an online consultation order your x-ray and your MRIs. If you called me and you’re in California or Texas, I’m licensed in both states, I could actually order your x-rays or your MRI if you need one. But more importantly, we could get on the phone or on a webcam visit right away to talk about what the issues are and figure out what you need to do.

So if you can go get in a doctor’s office and have them look at it and do that stuff right away, that’s great, but make sure you figure this out. So try these things. I’ll put up some other videos that show you the differences between each of these conditions and a cuboid stress fracture, and hopefully that’ll understand a little about what you need to know to get past this and get back to running as quickly as possible.

Now, if you liked this episode, please like it, share it, subscribe, and I’ll see you in the next training. Thank you.

image credit: 
Image published with permission under Creative Commons License: Image courtesy S Bhimji MD, Lau H, Dreyer MA. Cuboid Stress Fractures. [Updated 2022 Jan 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK542250/