Okay, our last speaker in this session, we're going to bring Holly back up to talk to us about Lisfranc and Midfoot, then we'll have the speakers up and do some questions. If I could just come back one more day in fellowship and do a calcaneus with you again, I'd be a much better surgeon. Okay, so I was charged with speaking about the Midfoot and Lisfranc, but I think for the purposes of your boards and of OITE, really focusing on Lisfranc injuries is probably more pertinent. So they're pretty uncommon, and even in my practice of 100% foot and ankle, we're not seeing 300 Lisfranc injuries a year, I mean, I really see a couple a month, and they vary in severity. They're only 0.2% of all injuries overall or fractures, they're commonly missed. And it's so important that any time you see anybody with an ankle sprain or they're on your schedule as deemed an ankle sprain, that you literally just put your hands on the foot and you palpate the Midfoot and just make sure that there's not a Lisfranc injury. They are missed so frequently, and the more, much more often I see Lisfranc injuries that I diagnose later than came to me billed as a Lisfranc. And the reason why it's so important to catch these early and to have such a high degree of suspicion is because the consequences of missing one initially are really poor, are really bad, and you know, people end up with really, really bad injuries. So this is a case where a patient presented to me late with, she was told she had, you know, an ankle sprain, and you know, you get a sense that there's something may not be right there. These were her standing films when she came into my office, and I knew she had a Lisfranc injury. And then I think two years later, this is the initial height of the Midfoot, and then boom, she comes back with this Midfoot collapse, and you can see this gapping plantarly at the Midfoot. And that's what happens when Lisfranc injuries go untreated. So just thinking about the bony anatomy of the Midfoot, it's commonly called a Roman arch. Dorsally, the bones are wide and they narrow plantarly, and this is also really important to keep in mind when you're fixing these, just in terms of screw placement. Really understanding the bony anatomy is important, and just pick up one of those, you know, plastic skeletons and look at the Midfoot someday, and you really get a sense of how narrow the plantar aspect of the second metatarsal base is. It's really important. The second metatarsal is sort of nestled in, in between the cuneiforms and at the base of the first, and essentially these thick plantar ligaments in the Midfoot lock the metatarsals, you know, into the Midfoot. So you need to know the Lisfranc anatomy, just some basic things. These are all, there's so many questions that come up in the OIT and the boards. The Lisfranc ligament is an interosseous ligament, and it connects the medial aspect of the cuneiform to the base of the second metatarsal. The plantar portion is the thickest and strongest portion of the ligament. I'm pretty sure this was on, there was a question related to that on my boards, and it stabilizes the foot in pronation and abduction. There are also some additional plantar transmetatarsal ligaments that connect the medial cuneiform to the basis of the second and third metatarsals, and these are said to confer some transverse stability to the foot, and the dorsal ligaments are known to be the weakest. So take-home points here, Lisfranc ligament is interosseous. The plantar portion is the strongest, okay? So just like everything else in the foot and really in orthopedics, there are indirect and direct injuries that, you know, that create these predictable patterns. So direct injuries like this foot on the bottom, these are often, this patient here had a big granite slab fall on her midfoot, but you'll see patients who've had their foot run over by a car, having machineries fall on the foot, those are direct crushing injuries. And then indirect injuries that we see more in football players, sometimes soccer players, car accidents, even just people walking down the street and stepping off a curb, walking down the stairs and slipping down the bottom step of the stairs, that's a very, very common injury pattern, where there's forced abduction with axial load on a plantar flexed foot. So this arrow is kind of demonstrating this. So most people present with pain and swelling, right? But in the more subtle injuries, there may not be a ton of swelling, they may come in two weeks after the injury, always look at the bottom of the foot. If there's plantar ecchymosis, in my experience, this is pathopneumonic for a Lisfranc injury. You know, obviously if they have a calcaneus fracture, they're going to get some plantar ecchymosis, but in the absence of an obvious injury, plantar ecchymosis equals Lisfranc injury. And again, just touch the midfoot, you just put your thumb in the dorsum of the midfoot and if they have pain between the first and second raise, it's a Lisfranc injury until proven otherwise. Most of the time it hurts to bear weight and this is another common sort of missed injury where they'll be billed as an ankle sprain and the patient will come in two weeks later with this big swollen foot and they can't bear weight. And so again, you're looking for this injury. So on plain x-ray, the injury may be missed initially. If there's any question and you've palpated the foot and they have this midfoot tenderness, you can do two things. You can get a weight-bearing x-ray if the patient can tolerate it and you can get an x-ray of the other foot. Oftentimes just looking at the other foot will give you a lot of insight as to what's going on. So if you go back and you look here, you know, this could be physiologic widening. You're not sure. They have a little bit of swelling, maybe an unreliable patient. When you get standing x-rays of both feet, boom, you really see that widening, you really see that widening here compared to the contralateral side and there's your answer. If you're unclear and if even on you get the contralateral foot, it still remains a little bit unclear, you know, you have to look for other signs on x-rays that maybe there's some malalignment. If you look at the medial border, the third metatarsal, that should line up with the lateral cuneiform. Unfortunately, you don't quite see it. It's better seen on an oblique film, but that's something to look for. Obviously, you look for widening between the first and second rays. In a lateral film, you'll sometimes see some dorsal subluxation of that second metatarsal base where it'll just kind of pop up a little bit. And then you'll often see a flex sign and that's where this interosseous component, this ligament, has able a piece of the base of the second metatarsal and you'll see some debris in here or you'll actually see a little sliver of bone, kind of like when you see a retinacular injury along the lateral malleolus or other type of avulsion injuries. This is a more obvious one on CT scan, but you know, you get a sense of it in here. If the x-ray is normal, the standing x-ray is normal, but you still are worried about it, you get an MRI scan. Again, if you have a high degree of suspicion, just get an MRI scan. The other thing about these being missed besides the consequences to the patient is their medical legal ramifications, and so it's really important to keep that in mind. You'll see edema on an MRI scan, you know, right where the ligament is. If you look on the, it depends, it's a coronal of the ankle, but it's sort of an axial of the midfoot. You'll see, you can see that plantar portion torn. You're also looking for step-off at the metatarsals to help decide whether or not this is going to be an operative case or not. And again, you're looking for that flex sign or any indication here. You can see some edema at the ligament. For severe injuries, I always get a CAT scan. It just really helps me understand the bony anatomy. Usually even with MRI scan, you don't get a sense of all the pieces that you either may have to reconstruct or even take out or do new to do your arthrodesis or your fixation. So moving on to treatment. For non, there's some controversy in this, and you know, this gets into more of the subtleties, I think, of the foot and ankle surgeon has to deal with, so I'll try to keep this really to what you guys need to know for your boards. But if the x-rays are normal and the MRI even demonstrates a Lisfranc injury to the ligament, or I'm sorry, an injury to the Lisfranc ligament, but no step-off or less, technically less than two millimeters step-off, you might see that in the blurb on the question, then you can treat these non-operatively. If there's any question about stability, so if the MRI doesn't show any step-off, but when you get an x-ray compared to the contralateral foot, you see step-off, that's displaced. The other way to check this is to do a stress x-ray, and you can either do this in the office if the patient can handle it, and this is where you kind of abduct the forefoot and try to get the joint to sublux, or you can do it in the operating room. Sometimes if I know there's a Lisfranc injury, I'm not sure whether or not it's unstable, I'll have the patient be non-weight-bearing and come back in a week or two, and then I'll try to get a better sense of it on clinical exam or with a stress x-ray. But truly non-displaced and stable patterns, I treat non-operatively for, I'm sorry, I treat non-operatively, non-weight-bearing for eight to ten weeks. So in terms of treatment, there's a little bit of controversy here as well, and I'll try to outline that. So for somebody who needs operative treatment, there is clear evidence in the literature that an open reduction with fixation is better than closed reduction, closed with percutaneous screw placement. So we know that you need to look at the area, you need to debride the area around the ligaments, and then you can fire your screws across, and that is superior to leaving the joint closed and just firing percutaneous screws. When we talk about where to put screw placement and how to fix, how to actually fix these, this is where there's some controversy. I'd be curious to see what the audience does here, but that's another question for later. But whether or not you put intra-articular screws or extra-articular screws, I don't actually fix them this way, but this is from an article from a recent Foot & Ankle International journal piece, but this is basically a joint-sparing approach. The long-term consequences of this aren't known, but there's a higher incidence of removal of hardware. And then the last controversy with ORIF is whether or not the screws need to be removed. This won't be asked because, again, the literature is still out there, whether having a broken screw in the foot matters, whether you take them out before, whether you take them out at three months or six months, that's still up in the air. I personally like to take the hardware out. So the last piece of controversy is whether to try to reconstruct the foot or do it with open reduction internal fixation without fusion, or to primarily arthrodesis these patients. There was a very well-respected and great study that came out when I was a resident. There was a level one study showing that with purely ligamentous injuries, primary arthrodesis resulted in a lower reoperation rate and slightly better outcomes followed out sort of medium to long-term. There's obviously less removal of hardware if you're doing primary arthrodesis as opposed to doing two operations. So I think, and correct me if I'm wrong, any of the senior people in the audience, that the answer for a severely displaced, purely ligamentous injury is primary arthrodesis. Is that the board answer now? Because it's still very, I know it's very controversial. I'm not asking what people do. I just want to know. I would be shocked if that's asked as a question. I think it'll be either the answer, but it won't be fusion versus ORIF. I just don't think there's enough consensus. Even though we have some good studies to support arthrodesis, we've got some very good surgeons that are still doing ORIF and having good results too. But I think the key here, and what Holly is saying, is rigid anatomic reduction and fixation is the key. And I think even amongst the staff here, we probably treat them differently. So for interarticular injury with comminution, in my opinion, primary arthrodesis is indicated because if you know there's a lot of interarticular comminution in these people, regardless of how stable the fixation is, they're going to end up with midfoot arthritis, so you might as well go ahead and primarily arthrodesis it. For chronic injury, that's another indication for primary arthrodesis. And just a comment, you never fuse the fourth and fifth TMT joints. They need to have some flexibility in motion in order for patients to accommodate uneven ground and for a multitude of reasons. But just know that that's never the answer. You can fuse the first, second, and third tarsomenotarsal joints. You can never fuse the fourth and fifth. You can pin them. So if they're displaced, you can pin them temporarily. I've never seen anybody plate them temporarily, but I suppose that could be an option. But always you take the hardware out at about six weeks. So missed injury leads to late collapse. DJD happens, you know, greater than 50% of the time. It's probably ubiquitous after a Lisfranc injury treated nonoperatively. Better outcomes are associated with the accuracy of reduction. For people who end up with bad midfoot arthritis after a Lisfranc injury or really bad midfoot arthritis in general, nonoperative treatment is sort of focused around shoewear. So you want to set them up with a rocker-bottom type shoe or something stiff in the shoe to take out as much motion as possible, because that's what's causing pain. And you know, a rigid or semi-rigid orthotic would be indicated. And then again, you can go forward and do fusion after the fact for late collapse. There's a higher nonunion rate doing it later, and I do warn people about that if they say that they don't want to have the surgery initially, but fusion is the surgical solution. Thank you. Awesome. Thanks.

Lisfranc injuries

ankle sprains

midfoot collapse

diagnosis

treatment options