Good evening. On behalf of AOFAS, I want to welcome you to the fourth webinar of the 2021 Foot and Ankle Focus Series. Tonight's program, Midfoot Arthritis, the Challenges, Solutions, and Unmet Needs, will be moderated by Dr. Judith F. Baumauer. Dr. Baumauer will be joined by Drs. Mark A. Glazebrook, Dr. Timothy R. Daniels, and Alistair S. Younger. You can find their full biographies and disclosures in the program document posted in the PRC. Registered live physician attendees may earn one hour of AMA PRA Category 1 CME credit by completing an evaluation and CME claim form at the end of the webinar. You can find the link to claim CME in the chat tab, and we will also follow up with an email to you following the conclusion of this broadcast. I'd like to run through a few housekeeping items before we kick off the presentations. Please make sure your speakers are turned on and that the volume is turned up. For technical assistance, you can reference the Help tab at any time. If you have any technical difficulties, your best bet is to close all your browsers and log back in the same way you did the first time. For technical difficulties, troubleshoot your problems. If you have continued to have issues, try closing all of your browsers and logging back in. This broadcast is being recorded and will be available for on-demand viewing on the Physician Resource Center at www.aofas.org slash PRC in approximately one week. We encourage you to ask questions during the presentations. To send your questions to the faculty, please click on the Q&A tab under the Navigation column. I'll now turn the program over to the moderator, Dr. Judith Bumbauer, to begin. Thank you. Well, thank you very much, Jennifer, for providing that information. I'm Judy Baumhauer. I'm at the University of Rochester, and it's my distinct pleasure to be the moderator for this Midfoot Arthritis, the Challenges, Solutions, and Unmet Needs. My disclosures. It's also my distinct pleasure to be joined by Alistair Younger, who's gonna talk about the diagnosis of midfoot arthritis and some of the imaging options we may have to better understand what joints are symptomatic and what joints aren't. Secondly, Mark Glazebrook, who's gonna talk about the treatments. Once we understand how to diagnose this, what's the best treatment options for these patients? And then Tim Daniels is gonna be the cleanup hitter for outcomes and unmet needs, since we recognize that midfoot arthritis is really quite a challenging problem, and there are unmet needs. And just to save time, they are all full professors. They're all fellows of the Royal College of Surgeons, and they're talented orthopedic surgeons and researchers that we're all familiar with, and I look forward to hearing their talks. But why is this important? Well, there was a prospective observational epidemiologic study that looked at patients over the age of 50 years, and they found that the prevalence of midfoot arthritis was 12%. This is for symptomatic midfoot arthritis. They also looked at the comorbidities as well, and found that it was more common in females, manual laborers, patients that were older, better than 75 years, and guess what? Our population is aging and living longer. Obese patients, patients who have previous trauma, or patients who have other joints problems suggestive that they have perhaps one of the osteoarthritic genes that we've heard about. One of the other challenges with midfoot arthritis, and another reason why it's important, is it really makes up a huge number of the joints of the foot. We recognize that the tarsal metatarsal joints, the first, second, and third, really have very limited motion, but the fourth and fifth allow us to accommodate to uneven rounds. They're more the mobile rays. But these joints don't just end with the tarsal metatarsal joints. There's the inner cuneiform joints, there's the navicular cuneiform joints, and as I just tallied them up, one, two, and three, here looking at the medial column and middle column, the ones that we tend to fuse, it makes up 10 joints. And guess what? Segmental fusions are hard to be successful when there are multiple joints at bay there. So how common is it to have a midfoot arthrodesis? Well, this study that was published in 2015 that looked at a database from 1994 to 2006, recognized that in general, foot and ankle arthrodesis were increasing during that timeframe almost 150%. And guess what? Midfoots arthrodesis and tarsal metatarsal arthrodesis were the ones that were increasing the most. So this is a really important topic. We recognize that industry has pulled an interest in this as well. We used to just do some cross screws across joints, and now we've moved to having all different variations of plating techniques and plate and screw constructs, trying to get us some compression, trying to get a span across multiple joints. And what's right? I'm not sure exactly. And there's variation in techniques which give us variation in outcomes. And that's not good for our patients. So there's big numbers, and there's big costs just with hardware. But guess what? The cost of surgery is also big. It can range all the way from 15,000 to 40,000 as I just surfed the internet looking at costs across the United States. So I'm really looking forward to letting the fun begin because these guys are fun. And I'll start it out with Alistair Younger, and then we'll go through some cases sort of illustrating our points. So here you go, Alistair. You're on. You're muted, Alistair. Hi there, can you see my screen? Okay, and just a second, I'm gonna get the slideshow going. We're all good? Everything look good? Okay, so I'm gonna talk about diagnosis of midfoot arthritis. Here are my disclosures. I don't think there's any that are particular relevance to this talk. And I'm gonna go through history and physical, which I think is the most important part of this. And even when I get three-dimensional imaging done, I still get the patient back and re-examine them with the result of that, because I think you'd learn so much more from physical examination and the various three-dimensional imaging parameters that may be of use just now. So midfoot arthritis and deformity, as Judy's outlined, is common. It's often under-recognized and under-treated. And the surgery may be for deformity, arthritis, or arthritis and deformity. So the physical examination needs to define both where they hurt and also where the deformity arises. We looked at our practice and we looked at 2,300 fusions, and we looked at non-union rates. And you can see that the midfoot fusions, the NC joint and the tarsometatarsal joint compromise 50% of the fusions being performed at our institution. And if we look at the non-union rate, we can see that the tarsometatarsal joint has about a 3% non-union rate, and that the navicular cuneiform joint has a 6% non-union rate. So the NC joint is one that's a bit harder to fuse, but not quite as difficult to fuse as the ankle. So the midfoot is challenging. There's lots of joints that close together. They don't move much. You have to locate the origin of pain and deformity, and it can be a younger patient's disease. So this is just one illustrative case showing the challenge. This lady has arthritis at the NC joint and the TMT joint. You can see collapse at both and loss of her arch. So the question then is, what do we fuse? In this particular case, we got a CT scan. We're able to see collapse and bone loss at the NC joint, which will indicate that you need some grafting. And this is the interoperative pictures showing a 1, 2, 3 TMT fusion and NC fusion. This I do from the dorsal side, and I try and make sure that there's adequate fixation on all three joints as a non-union, and one of these joints can cause symptoms. So there's an importance on the clinical examination in the history. You need to determine the deformity. You need to determine the location of the pain and the arthritis, and you also need to determine the impact of the symptoms, because that will determine how you treat them. So I like to define disability. The question I ask patients is, what can you do that you would like to do because of your midfoot pain? But you can also quantify this. And Judy sent me this really nice slide showing the PROMIS scores through treatment of a midfoot arthritis, showing how the scores go down immediately after surgery and then come back up. We use EQ5D, and as you can see, that's a much blunter instrument. And so I think that the outcome score you use is important if you're gonna quantify to patients how they've improved. On physical examination, I'll get the patient to stand up. It's important to see them expose both feet and get a comparative view, watch them walk and see how much instability there is in the midfoot, and then get them to sit down and assess the alignment using parameters that you can assess intraoperatively. And finally, go through each joint and determine which is a symptomatic joint via palpation. One of the things that I find important to determine is the forefoot varus and the hind foot. And on the right-hand side here, you can see the forefoot varus, and intraoperatively, you can see how this has been corrected because if you don't correct the forefoot varus, the patient will end up weight-bearing the latter board of the foot, and it's a very difficult thing to treat. So this is a part of the deformity you need to both analyze in the clinic and correct when you do surgery. There's also external rotation of the forefoot on the hind foot, which is part of a plane of varus deformity that can initiate through the midfoot collapse in arthritis. And so looking at the tibial tubercle and seeing where the forefoot sits is important. So again, you can determine this intraoperatively and correct it as need be. I then will go through palpation of each of the joints and find them. So the problem is to locate the symptomatic joint. So you don't want to be fusing the wrong level. And early in my practice, I realized if you fuse the NC joint or the TMT joint when the NC joint was symptomatic, then patients fail to get a reasonable result. And so it's really important to isolate this. So is it the first TMT joint, the second, or the third? Is it the NC joint, the medial, intermediate, or lateral side? And on occasion, even though we're not talking about the TN joint, the TN joint symptoms can be confused with the NC joint. And you may need to fuse more than one level or more than one joint to get appropriate symptom relief. And just because the arthritis is present on the x-ray doesn't mean to say that it's the cause of the symptoms. So you can palpate the first TMT joint illustrated here on the left, the second TMT joint, and the third TMT joint on the right. So the friend of this is that all of these joints are millimeters underneath your palpating fingertip. And it's one of the joys of foot and ankle is that you can get your fingers right next to the joint that hurts. It's important to get standing AP and lateral views of both feet. Now you can see on this, there's a number of issues going on. We've got arthritis of the tarsometatarsal joints and also metatarsus adductus. And on the other side, a hallux valgus deformity with lateral drift of the toes. So all of this comes into the clinical picture that you're going to need to treat. And you still need to sort out, even though there's not obvious arthritis of the navicular cuneiform joint, whether or not the navicular cuneiform joint is a problem for this particular patient. This is this lady standing. You can see the forefoot varus on the hind foot. You can see the deformity. And I then go on and palpate to identify the symptomatic joints. But I look at this a lot, this forefoot varus in the hind foot, particularly in the midfoot arthritis cases to try and work out where the collapses occurred. This also gives me a reference point that I can use on the OR table to see if I've corrected the deformity. CT scans are valuable. I use them a lot. I try and just use regular CT. The quality of a plain CT is often better than that that comes with a spec CT. I will use spec CT on occasion, but it requires the technologist to correctly line up the two scans and make sure that they're appropriately exposed. And sometimes that can be confusing. And again, neither of these replace clinical examination to determine the level of your arthritis. Standing CT is really useful if you can get it, and it will help you identify the area of collapse and also potentially the area of arthritic change. MRI is occasionally beneficial. I don't use it much for midfoot arthritis. I tend to find that the signal is high and the diagnostic accuracy low. PET CT may well be the way of the future. We have not had that available to us yet, but I think that this is a technology to watch in the future. So in summary, midfoot arthritis is common. It may be part of a complex forefoot and hind foot deformity. It can be a cause of significant disability. The diagnosis needs to cover the disability and location of both the source of the pain and the source of the deformity. And clinical examination is your mainstay and advanced imaging is often necessary. So Judy, I will stop my share and get it back to you. Thanks Alistair, that was great. Mark, we're gonna turn it over to you to tell us how to treat these challenges. Well, thank you, Judy. I thank the AOFAS for having us tonight. It's special for me to be here tonight because I'm getting to work with my four best foot and ankle friends. I love working with these guys and girls and it's really an absolute pleasure to be on this panel with you. Thank you very much. So I'm gonna talk to you a bit about my approach to the treatment of midfoot, sort of where and when to fuse. And I'll be echoing some of the things Alistair said, but there's a few areas I wanna highlight and a few areas, believe it or not, I disagree with Alistair. We'll move that along. So these are my disclosures and I would draw your attention that I am currently a consultant for Stryker and I've worked on the randomized control trial, FDH trial for the augment bone graft and I will be mentioning that in the talk. Of course, Stryker acquired Brighton Medical who acquired DMTI, which is where it all began for augment. The rest of my disclosures are not in conflict with this talk. So in an overview, we're gonna talk a little bit about the anatomy and why I think it's important and how I view it a little bit different in some way. My indications for midfoot fusion. I wanna talk in particular about multiple joint arthritis and which joints to fuse. I think Alistair gave us a good idea there, but I have a little bit of a different approach. I'm gonna talk about the various surgical implant options for midfoot fusion that you're all aware of. And I'm gonna show you my technique and what I think is important and follow it up with a few cases. So first of all, anatomy. So I tell my knee and hip arthroplasty guys that their job is easy. They have two bones that come together of the joints they work on and it's very straightforward and easy. Unfortunately, we have 28 bones in the foot and the midfoot includes about 12 or 13 bones depending on how you count them. There are seven parcels and five of those are in the midfoot and the five metatarsals also form a portion of the midfoot, at least the midfoot joints. I actually consider the talonovicular joint and the calcaneofubular joint part of the midfoot. I find, I consider the hind foot really the ankle and subdual joint, but I know that's not a conventional anatomy. So for me, there's 13 options, 13 joints to fuse in the midfoot. The talonovicular and the vicular cuneiform, TNTs and the cuneiforms and the calcaneofubular joints. So there's a lot going on here and as Alistair so nicely put it, there's a lot of anatomy and a lot of deformity potential. This is a study by Ryan who looked at the actual size, the average joint depth. And it's important to understand that there is some variability as your foot gets bigger. So this slot is rather bigger, rather busy, but if you pull it along, this is for all foot lengths and then the foot gets bigger in anatomical specimens. As you can see, as the foot gets bigger, the metatarsopineiform joints in fact do get bigger. The take-home point from this slide, when you're doing a dorsal approach for effusion, you have to appreciate that these joints are deep, sometimes three centimeters deep and they're difficult to see the bottom, especially if you're distracting from the top with some sort of laminar spreader, you can actually compress the bottom part of the joint. So you really have to pay attention to the size of the joint. This is just another study that looked at the metatarsopineiform joints. And you can see again, these joints are large joints. So you have to be very aware to do an adequate de-broadening infusion, there is a deep joint. If you place your fusion to dorsal, you're gonna get a gapping at the base of these joints. So that's important, the anatomy of these joints. So what are my indications for mid-perfusions? Well, I think we know a chronic miscellus-branched arthritis is a definite indication. Hallux valgus, when you wanna choose a lapidus-like procedure or a modified lapidus proximal for large deformities and instability. Acute and severe fractures sometimes require infusion acutely, but that's very rare in my ends. Foot deformities, I think Alistair did a good job of showing us those. And finally, the dreaded charcot foot which calls for very aggressive fusion type procedures. My contraindications would be an active infection. Of course, I don't wanna add hardware to a infected bone. An active acute charcot when the bones are too soft to fix. I usually wait those out until they go through the ICML stages. And finally, widespread mid-foot arthritis. I'm gonna take a minute to tell you what I don't like about widespread total mid-foot arthritis. You can see here on this x-ray, there is multiple joints involved. And this is usually the elderly lady who shuffles into your clinic and she complains of pain all over her foot and she points into several areas. I think if Alistair's palpating to check which joint it is, he's gonna find every joint in every other foot tender. If you attempt to do some of these, you know, some selective fusions, you're gonna transfer those stresses to the other joints that are arthritic. So I think when you have multiple widespread arthritis, like this patient does in this x-ray, I really think you're gonna have to agree that non-operative treatments may be the best option. If you try to fuse some of these joints, you may aggravate the other joints and set that domino effect into place where you're fusing all the joints. And certainly, a lot of the elderly people can't tolerate this. It would be nice if we had some arthroplasty or some motion sparing operations for these difficult cases. So how do we know which joint to fuse? So here's a case I wanna show you. When you look at this x-ray, especially in the lower, you can see, there definitely is one area that's very suspicious for arthritis, but there's a number of joints that look like they're arthritis. When a patient points right here at their midfoot, you can see they're actually pointing at several different joints. My health patient skills aren't as keen as Alistair's. I find the joints very crowded, and I'm really often not sure which joint is symptomatic. So in this x-ray, you can see that for diagnosis, it could be TN arthritis, subtalar, ankle, or TMT arthritis. And the various options would be a midfoot, double pan-talar, or multiple fusions. So you need further diagnostic imaging, and I know Alistair showed us this. I find the CT scan alone really not helpful. I don't think it adds much more to the plain x-ray. You can see here that there still are a number of joints on this CT scan that are suspicious. We call this the poor man's CT spec scan, the bone scan. If you don't have a CT spec, a bone scan with a skilled radiologist can correlate exactly where the problem is. So you can see here, we're zeroing in on the TN joint, despite the other joints looking arthritic. And here is my favorite investigation for differentiating which joint to fuse and isolating what the problem is, the CT spec. I find this extremely helpful for midfoot arthritis, and I warn patients when I send them for this, if a lot of joints are lighting up, surgical options may not be appropriate. So I rely heavily on the CT spec scan. And back to this x-ray, you can see the CT spec told us we had a talomavicular arthritis condition, fairly isolated with the only activity, and this called for a midfoot TN fusion. I like to do this just with a couple of compression screws, well spread out to control rotational motion. So what other implants can we use for midfoot fusions? This here, if you like, is your buffet. For some, not all of the options for midfoot fusion. And I'll just say a few words about each of these. It's beyond the time to look at these here in detail. This is my favorite, the multi-use compression screws. I find these screws deliver a lot of compression at the joint surfaces. And I also find with their cannulated technique that you can precisely deliver these screws exactly where you want them. I would be critical of myself in this x-ray and say that maybe these screws are a little dorsally placed but it's hard to get them to penetrate the screws alone. But the only time I really use plates and well, maybe not the only time, I use plates in an unstable situation or more osteoporotic bone, but plates are good when you have to bridge bones. If you have collapse of some of your midfoot bones and not enough real estate to get compression screws in, I like midfoot plates and they bridge the joints that I may not be fusing temporarily or for multiple fusion I'll use these plates as well. I like this plate, I use this for isolated fusions. This is just a little, they call this the claw plate with kind of reverse crimping of this plate. You can draw the two fixation points together and get some compression at your fusion set. This is a nice device that I've used as well. This is a hybrid fixation. You get benefits of compression and plating all in one. I think it was Keith Walker that did a lot of the early development work on these types of plates. So these are a great plate when you really need a good rigid configuration to get some compression as well. And then finally, and uncommonly, you can use external fixation. I do use external fixation, especially if there's a temporary infection or a diabetic unstable foot. And I often use it for severe comminuted post-traumatic situations where I just want to get that mirroring angle back to its anatomical alignment. So this is rather uncommon, but sometimes it's a must. I draw your attention to this study by Christy Giovanni. Chris looked at this, used this level three retrospective comparative study and looked at 189 midfoot joints by nine different surgeons doing midfoot orthodesis. The overall non-union rate was 11%. So non-union rate, depending on which study you're looking at, can be very high. There is one study in which it reports up to 40%, which I think is a little high. I think this number really gets around and you can tell your patients. I tell my patients between 5% and 15% non-union rate. He found that when he looked at these cases, that plate fixation had a slightly increased risk of non-union, with an odd ratio of 6.2. Smokers, of course, an odd ratio of 7.9. And non-anatomic alignment, or maybe failure of surgical technique, a high independent risk factor. He found that bone graft was slightly able to mitigate these problems. Another paper here, just to reemphasize that smoking is very bad for midfoot fusions and non-union rates are significantly higher. So you have to counsel your patients about smoking. So for techniques for midfoot fusion, I think we all know that you've got to debride the cartilage, expand the subchondral, remove the subchondral bone and get into that soft, spongy bone. I like to pharage my joint services. I call them osteoblast and osteoclastic highways for the priority site where the fusion is. I almost always use bone graft or bone graft substitutes in the midfoot, the internal fixation that we just described with compression. I put this little movie just to show you, this is in the ankle, of course, but this is to remind you that non-mechanical instruments are better than mechanical instruments. They generate less heat. A fusion is a biological operation. All the hardware you put in is temporary. The bones must be used for it to be successful. I've added this slide to tell you a little about irrigation. This is MTP joint irrigation with a reamer, but you can see here in this little study we did, without irrigation, you generate very high temperatures. With irrigation, the temperatures are much deeper. So if you're gonna be using mechanical instruments and sometimes you have to, sometimes you need the burr to get into those concave joints in the midfoot, I would suggest you use irrigation. This is just a case of an increase in metatarsal with some instability at the TMT joints. We did a modified lapidus procedure here, a dorsal medial approach. I do use a saw for my lapidus to get a nice straight cut. I often use autograft. Just to worry about autograft, you need a structural graft if you're gonna be doing deforming correction. Some of those planovagus x-rays that Alistair showed, a tricortical graft to jack out the lateral column of the foot is quite effective. So I will use structural iliac breast grafts rarely, and we might have a case later to show you about that. And you can use, for a non-deforming correction, you can just use regular autograft. I think in this day and age, you really have to give consideration to bone graft substitutes. I think we're all aware of the 2013 study led by D. Giovanni where they established augment or platelet-derived growth fracture as a safe effective alternative to autograft in the hindfoot ankle fusion surgery. So I think if you're gonna be taking the patient's own bone using an X-transition, there should really be a good reason. However, sometimes these devices can be cost-prohibited in certain standards. Sheldon landed an excellent review on bone grafts substitutes, so I would draw your attention to this for added reading. So finally, this is the finish of this case. Again, I just used two cross crews. This is a modified lapidus to realign the first grade for base. Last, this is just one last study. This is another modified lapidus for isolated midfoot arthritis of the TNT joint. You can see here that I used a hybrid plate with compression and plate fixation. And finally, another isolated midfoot fusion of the tail and adductor joint using this CT spec scan to isolate the active anatomy in two simple screws. So with that, I would summarize by saying the midfoot has many joints to fuse. The bone scan or CT scan is helpful to localize the pathology and rule out that overactive foot where you really can't help, at least in my hands. There's many options for fixation and you can use what you're most comfortable with. Compression is important and you can mitigate non-union or people that are more likely to have non-union by using non-mechanical instruments, autografts or bone graft substitutes and rigid and joint fixation. Thank you all for your attention. I appreciate the opportunity to share my midfoot practice with you. Thanks, Mark. So we have a couple of questions in the Q&A, but I'm gonna have Tim speak first and then we'll address these questions right after Tim's talk. So before the cases. So if you have more questions, pop them in. Tim, you're on. Thanks, Judy. And I echo Mark's sentiments about being on this elite panel. My disclosures are very similar to Mark Lacebrook. So I'm not gonna go through those disclosures again. This is a complex topic. Midfoot arthritis, you can see it in pes planus deformity, pes cavus. You can see it with forefoot deformities. You can see it in isolation. And they're not all the same as we know. I'll never forget in my first year of practice, I had a 70-odd-year-old lady come in and she had the subluxation at the lisfranc joints that Mark showed in one of his radiographs. And I thought, well, this is a slam dunk and no history of trauma, by the way. I thought, you know, I'm just gonna go do a TMT fusion and she'll be fine. She was a rock around my neck for a good three years because the TMT fusion not only went on to non-union, but really the TMT joints weren't her problem. Her flat foot was her problem. Now, if I see that, I focus on the flat foot reconstruction even more than on the TMT joints. So it's hard to talk about this topic in one bucket because there's so many varieties. You can see a Charcot-type collapse of the midfoot with no diabetes. You can see a collapse with diabetes. And you can, like I say, you can see it in flat foot cavus and many, many scenarios. I think there's certain principles that Alistair and Mark brought forward, which are very important and needs to be applied, but you can't forget about the rest of the foot. If you've got isolated midfoot arthritis, you need to think about the forefoot. And if you've got associated foot deformity with the midfoot arthritis, you need to think about correcting that deformity in addition to your midfoot surgery. I find midfoot surgery complex. It's not my favorite surgery. It takes a long time. And I don't know about other countries or other provinces, but in Ontario, it reimburses really badly for the time you spend on it. These are tough operations. There isn't a lot of information on outcomes. This paper by Bruce Sandjorsen noticed that in patients with mid-tarsal arthritis, they had a second mid-tarsal that was longer than their control group, which obviously makes sense to me or makes sense, period. I, in my own practice, have noticed, and I'm talking about the isolated TMT joint arthritis. So I'm talking about patients that come in with localized pain at the second and third tarsal, mid-tarsal joints with not much of a foot deformity, except for the forefoot adduction that Alistair has eloquently displayed. But nonetheless, I've noticed a large percentage of these patients have forefoot adduction, something that I don't think really has been looked at carefully as far as the literature is concerned. The other thing that I found difficult with midfoot fusions is balancing the forefoot. And if I'm doing, not necessarily with forefoot deformities, but if I'm doing isolated TMT joint fusions because of isolated arthritis in that area, I often warn the patients that a year or two down the road, there might be some fine tuning to do to the forefoot because it doesn't take much to offload a mid-tarsal or overload a mid-tarsal or create a plateau where one didn't initially be present. This is, I think, probably one of the more extensive reviews out there. And I know Judy's on the panel, but it is what it is. And in this review, Judy noted a non-union rate of three to 7%. Mark very eloquently went over other papers that demonstrated a much higher non-union rate. In my practice, the non-union rate is probably over 10%. Fortunately, the ones that require surgery for non-union are probably in the 3% range. So if we looked at non-union as a diagnosis that requires further surgery, I think we're looking at a three to 7% non-union rate. But if we look at the asymptomatic fibrous unions, I think we're getting up to 15, 20, 40% that some of these papers show. So part of it might be reporting. Reoperation for a fibrous union at the TMT joint is actually, in my experience, relatively low. Most of the time, these patients are not symptomatic enough to warrant a reoperation. This is a 64-year-old lady that came to me with symptomatic mid-foot arthritis. This video is, I'm focusing on the TMT arthritis, so the second and third metatarsal-metatarsal joints, and not the Charcot-type collapse or the pes planus or pes cavus deformities, that which some of the radiographs depicted with the other speakers. So she had the forefoot adduction, which I commonly see. She had a symptomatic helix valgus deformity and this TMT joint arthritis. So I use a midline incision. I don't use double incisions. This is the midline incision here. I do use transverse incisions. I'll talk about them later. But I'm very careful about mobilizing the deep nervous or structures. I take my time, mobilize them so that I can take them both medially and laterally, particularly if I have to deal with the first TMT joint. And then in many patients, there's a thick, this lady doesn't have a very thick periosteal layer, but you can see that I'm taking my time as I move through to elevate this layer. If there is a periosteal layer to elevate, my bias is the surgeons should take their time, elevate this layer as one component, because it makes such a nice closure afterwards if you could take this periosteum and re-approximate it to some extent. And in my mind, it helps to decrease the chances of a non-union or fibrous union. So here's the TMT joint, and I'm deriding the osteophytes. Here, I'm showing the depth of the joint, and this is what Mark emphasized. You have to get right to the bottom of this joint, and you need to distract it appropriately. Now I'm taking the extensor digitorum longus. I'm gonna reflect it in a medial direction, and I'm doing a bit of a dissection here with some Brownian motion to expose the third metatarsal joint. Now, this joint is not easy to expose because it's downhill. You really have to work down the hill and around the corner, and this is why some people choose to use a separate incision to expose the third TMT joint. Now, since I started using more transverse incisions, I don't find the exposure as difficult. Now, in this patient, she also had intercuneiform arthritis, so here I'm using a distractor. The intercuneiform joints are more of a fibrous arthrosis as opposed to a synovial joint. There's a lot of intercuneiform ligaments that need to be debrided. There's not as much cartilage as there is in the TMT joints or the tarsal metatarsal joints, but careful debridement is required. Minimal bone resection when you're doing your burring. If you resect even two or three millimeters more bone than you expect it to, it can lead to dorsiflexion of the metatarsals and a metatarsalgia or transverse metatarsalgia. So I've put a screw across the cuneiform joint, and I'm using a four-hole plate. There are better plates on the market now. They've gradually evolved to be more robust. Now, whether or not they help with the nonunion rate, I'm not sure. I think preparation of the joint and proper bone grafting is essential. I'm checking under floral to make sure I like the position of my plate, and now I'm using morselized bone and platelet-derived growth factor, similar to Mark, to prepare this joint. Now, you might ask, well, why aren't I compressing this joint? Why am I not putting a compression screw across here? Well, I find if you compress these joints, that's when you run into forefoot problems because you shorten those metatarsals, and they come back really quite unhappy because you've offloaded two metatarsals, a second and a third. They're putting a lot of weight through the first and the fourth, and they just don't like it. So I'm very careful to make sure that I'm thinking about balancing the forefoot at the same time that I'm doing the midfoot fusion, and even a small deviation from where they should be can lead to substantial distance deformity, either dorsal or plantar, the metatarsal at the forefoot. So here's this patient. I did a scar fosteotomy on her as well, and there is a screw backing up. You can see that she's got a fibrous union at the second tarsal, metatarsal joint, but it's asymptomatic. The screw wasn't even symptomatic. I convinced her to allow me to make a small incision and take it out, but she was not having any substantial symptoms at those joints. But again, I wish that these type of x-rays were uncommon, but unfortunately, I don't believe they are. If we look critically at our practice, probably, at least in my practice, the nonunion or fibrous union rate in midtarsal joints is the highest of any joints that I fuse, and I do consider myself a fairly careful surgeon. So this is a transverse incision. The guys at Duke told me that I was crazy to do longitudinal incisions. I should use more transverse because you can expose the entire midfoot. I've started using transverse incisions in the midfoot, not for everybody, but on occasions, particularly if I feel that the third tarsal, metatarsal joint or the lateral tarsal, metatarsal joints need a lot of work. And I've had good healing rates after these incisions. Now, if you look at the angiosomes of the foot, this incision is actually between two angiosomes, which actually, which makes sense as far as healing is concerned because less retrograde flow is required to heal this area. So, Judy, not a lot in outcomes. It's a potpourri of different types of deformities. The etiology surrounding midtarsal arthritis is quite diverse, which you can see from Alistair and Mark's slides. And it's really difficult to talk about this entity as one, you have to consider it as a complex entity and take everything else into consideration, including a tight heel cord, which Alistair pointed out on one of his slides. Thank you very much. Great, thanks, Tim. As promised, I'm going to just pull up the Q&A questions right now, and then we'll do the cases that we have. So, Dr. Shaw was asking a question. He said, when do you use diagnostic injections? Alistair, why don't you take that one? Yeah, I think injections are helpful for treatment. I'm not sure that they help with diagnosis because if you inject the TMT joints, it can go into the NC joint and it may confuse your diagnosis. So I actually don't use it for diagnosis. I use it for more for treatment. I don't know how the rest feel about that, but that's how I consider it. I'm not concerned about transmission between the joints. Yeah, I feel the same way that it might actually spread from the first to the second to the third for the TMT joints as well, as we found in a study. Dr. Fernandez is asking the question, what about plantar plates in the medial column? Mark, why don't you take that one? I think there's certainly a role for plantar plates in the medial column, especially with mid-foot collapse in plantar valgus wood. And even more importantly, maybe with your Charcot severe mid-foot collapse to give that buctus bridge effect as well as good compression. Although I think what we're finding is those bolts and bars, the long intermediary screws from the metatarsal head up into the navicular right across Mary's ankle into the talus, neck and body is replacing these as well. But I do think there is a role for plantar plates with collapse. Anybody else? Any other comments about plantar plates? They're great. I prefer to use them, but it's usually in the Charcot type reconstruction with the collapse of the mid-foot. Sorry, Alistair, I interrupted you. Sorry. I try and get fixation plantar, but I use the full thread screws to do that. So if you peel off the cartilage from subchondral bone, subchondral bone is your strength of fixation. And I try and make sure that my cross screws are going plantar to get the joint closed in the plantar side. I also will compress just one screw. So I get my compression with one screw and then all the other screws are under drill both sides so that we get fixation on both sides of the joint with full thread fixation. So slightly different approach than the plate approach to my fixation. Dr. Hurlwitz asked the question, what do you do for a bad four or five, you know, CMT joints at the cuboid? Tim, you want to take that one? Well, it's a tough one. I used to use Bob's Balls, but they're not available any longer. Fortunately with the nature of my practice, I haven't had to deal with this, that type of arthritis for about five to 10 years. And to be frank with you, Judy, if I was forced to do, if I was in a situation now where I had to manage it, I'd probably think about a interpositional arthroplasty, but there is definitely a need for better implants for that side of the foot. Patients don't tolerate fusion, lateral fusion as well. Judy, I would echo Tim's thought. That's really a need we have in orthopedics. To be honest, I've never ever wanted to use Bob's Balls. I'm not sure why Tim would, but anyway, for now there's really nothing that we have to keep the motion there. And certainly I don't think that you really can fuse those joints. I think they're really not a joint that wants to fuse it. Alistair, do you ever fuse it, or what do you do? No, I don't fuse it, but I think if you get the medial column back on the ground, if you restore that, we learn about the medial arch of the foot. If we can restore that, if you look at the patients that get arthritis or symptomatic arthritis in the fourth and fifth TMT joints, they have an insufficient medial column. As Tim was pointing out before, make sure you're looking at the whole foot on this. If you get the medial column back on the ground and the weight bearing through the medial column, the fourth and fifth TMT joint arthritis hopefully will not hurt anymore. So I concentrate in restoring the medial column. I don't worry so much about that fourth and fifth TMT joint arthritis. And our good friends from Greece were asking the question, in the case of Mueller-Weiss and lateral navicular collapse, what is your favorite technique for restoring length and fixation? Difficult problem and a little extension of midfoot arthritis for sure. But Mark, you wanna comment on that? Yeah, sure, Judy. This is an example where I think bridge plating may be necessary. The collapsed bone also is usually necrotic. So I definitely use bone graft substitute and usually use a biologic. So I think this is the time where my adage of nice compression screws is all you need will not work. You need something more broad. So I will bridge the joints that you're gonna use. And I think really important, you need to counsel your patients because often you're dealing with dead bone in a very mechanically unstable environment. You gotta tell them that the non-union rate is gonna be even higher. So they gotta know what they're getting into and they gotta pull all the tricks out that they have. Yeah, it's definitely, the primary problem is that the blood supply hasn't been good and now you have a sclerotic nickel wafer that is difficult to incorporate into a fusion for sure. Next question is, does anybody have a problem using Ken Silla's bone from the calcaneus for a TMT fusion? I don't, if you chose to do that, that's perfectly fine. I think that that was great. That's my go-to area for bone graft, Judy. Alistair, would you address the pes planus overpronation when dealing with midfoot arthritis? Absolutely. I think it was either you or Tim said, or Mark said, I can't remember now, that it doesn't come in isolation. So now we've placed midfoot arthritis and something else. So now, and overpronation and pes planus. What would be your approach? Well, it's in the cases that we've got there, Judy. Yeah, it is. Correct, you know, restore. If you look at the lateral view and that standing CT was really illustrative, but your standing x-rays are illustrative and the collapse occurs at the NC joint most of the time. So I do lots of NC fusions, but if you do that, then you're not often controlling the external rotation of the forefoot on the hind foot. So I'll do a lateral column lengthening, more to de-tension the NC fusion. And I might consider a delta ligament repair on occasion, but if you restore the bony anatomy, everything else kind of comes around. If you try and deal with it through soft tissue, you'll often fail. So NC joint is my go-to for midfoot collapse, followed by first TMT joint, followed by possibly one, two, three TMT. But you absolutely have to get a proper arch reconstruction done. If you're going to be dealing with a flat foot with midfoot arthritis. And hopefully we'll get to that case. So Mark, there was a question in regards, Dr. Veeb asked, what's your post-operative protocol in terms of weight bearing for your midfoot fusions? Yeah, to determine fusion. I'm very conservative with my post-operative protocol. I use the old orthopedic adage of six weeks in a cast, non-weight bearing. Then I convert them to a cast boot and 25% of body weight per week over the next three weeks. So I tell my fusion, midfoot fusion patients that they're going to be off their foot completely for six weeks and then progressive weight bearing for another three weeks. So nine to 10 weeks total before they can walk on their own. I know it's a little aggressive, but that's what I do. A great question. Would you ever do an isolated gastroc? If somebody had a positive silver skull test and some midfoot arthritis, would you do an isolated gastroc to see if that just off weighting the midfoot with an isolated gastroc would work? Anybody be willing to do that? I would. Doesn't burn a bridge. Yeah, it's a bit of a risk and there might be, you know, something that's relatively easy to do in an elderly patient. But I would have a long discussion with the person before I did it. Be an awesome study, like some evidence on it. I think it'd be just great to study it. Just without that, I don't know what, if it's going to be beneficial at all or not. I think with mild arthritis, it's not too unreasonable, but I don't think I would do it in isolation with any kind of significant effluence. Okay, let me just pull up a couple of these cases because they're going to illustrate some of the points that were just asked in the chat. I believe, Mark, that you're starting it out. Sure, yeah. Sure, yeah. So, we'll look at this clinical case. This is a 56-year-old female with pain and deformed feet. She's had progressive deformity over four years. She's not fitting well into her shoes. Really, it's a flat foot that she complains of. Of course, worse with activity and better when she's off of it. She's not able to do her grocery shopping now. So, that's sort of an indication for me that surgery is going to be probably needed. And she failed to run off of feeders, of course. She does have a history of rheumatoid arthritis and she's on NSAID and demerits. Next slide. So, on examination, she was otherwise normal. Her rheumatoid was very well controlled with her demerits. She did have a significant planovagus deformity. She was tender dorsal and plantar in the midfoot region and in the peripheral region. She had a callus on the medial plantar side and she did have a tight Achilles with mod correction with knee flexion. So, she was silver-spooled. So, this is her x-rays. And I apologize that they're non-weight-bearing, but I think you can see even with them being non-weight-bearing that there's significant arthritis in the lateral midfoot area or the calcaneocuboid joint area. And she also has some fibular infringement. So, next slide. The CT scan really gives the whole story. You can see this is severe degradation and erosions and deformity at the calcaneocuboid joint causing this severe planovagus deformity and pain localized right to this area, almost in isolation, which is a little unusual for a rheumatoid foot. So, next slide. My treatment choice for this patient was as I suggested earlier, this is where I like a structural graft. Now, there's commercially available structural graft substitutes, which I think are reasonable. But this, of course, is free to the patient bar the possible morbidity at the graft site. This is a simple tricortical iliac crest bone graft. And I used a bridging plate on the cuboid over to the calcaneus with this correction in mind provided by both the plate and the structural support of the graft. Next slide. And you can see our post-operative films here. Well, interoperably, I stuffed cadcellus bone graft with a bone graft substitute mixed into it around this construct to fill the gaps that the structural graft left. So, I had a good rigid construct with good biology here. And you can see I was able to get that lateral column back over the length and correct the deformity. The last slide shows the patient at a nicely aligned foot, a good clinical scenario for this patient. One more slide, Judy. So, that's just an example. Again, another one, sorry. That's just a good example where Allister, I thought, did such a great job at the beginning of showing us how mid-foot arthritis can lead to deformity. And using this structural graft, we were able to correct the painful arthritic site and correct the deformity with one small operation. Anybody have any comments about that particular case? Good job, Mark. I had done much the same. Here's to you, Mark. So, Allister, you're up. Okay. So, this is a patient that presented to me many years ago. She had bilateral painful flat feet. She had mid-foot pain. And if we go to her x-rays, we can see what the problem is. If we look here at the first TMT joint, you can see how it's collapsed into dorsiflexion. If we look at the AP view, we can see arthritis and some Lisvank joint collapse in the valgus at the first, second, and third tarsometatarsal joints. You can also see that the NC joints has collapsed too. So, going on to the next slide, this was 2004, and then she had a similar operation in 2005. So, if we just go on to the next slide, you can see what I did. There's a gap on the dorsal side of the first TMT joint. So, I used Iliac crest graft to go into that to bring the first ray down to the correct length. So, you can see that it's kind of restored in length to the second and third metatarsals, and it allowed me to both deal with the arthritis and correct the deformity. This was a single-stage procedure, and in that time period, my NC joints were done from the medial side, which I think led to a higher non-union rate, and I was also correcting the lateral column with a lateral plate here and going through the CC joint like Mark just illustrated. Now, I do lateral column lengthening through the anterior process of the calcaneus, and my NC fusions are done from the dorsal side, and I try and get two screws across each joint, like I showed earlier. So, this showed, I think, reasonable correction, and I've got follow-up on her. So, if we go to the next slide there, Judy, this was actually her recovery, and you can see that the first ray is maybe not down far enough to correct the forefoot varus. And then, if we go to the last slide there, I think she got post-traumatic arthritis. She had an ankle fracture, so I saw her back for that, and I got this sort of final follow-up on her. So, almost 18 years later, the right side I reconstructed in a slimmer manner. It's doing well. This side, I had to deal with mid-foot arthritis, some residual deformity, and an ankle fracture that collapsed with some AVN. So, I still had to correct her forefoot more when I did a total ankle, but I think it shows reasonable durability for these reconstructions, if you can get the foot straight. And this side, maybe I didn't get it straight enough. Anyway, just, I thought it was good to see this long-term follow-up of this case. On the other side, she's doing great with over 16 years follow-up. So, deformity correction, I think, is really important here. I think it also highlights that it's not in isolation. You know, once you lock up some joints, it has impact on other joints, even though it might be very minimal motion, it's probably gonna put some stress on adjacent joints. So, I think we should go back to just answering a couple more of these questions that just came in. So, I guess, does anybody use a tightrope construct? I saw that there was a tightrope, and was it in yours, Tim, or somebody's? Yeah, she had that surgery done at St. Elsewhere. I don't do that. Okay, so that was just an incidental finding. So, erase the tightrope thought from your- I'll use an internal brace occasionally for the deltoid ligament, from the navicular back onto the anterior process of the calcaneus, if that's a major part of it, but I have not used it in the midfoot outside of trauma yet. The guys in Switzerland had an interop pedobarographic plate that they were experimenting with, and they found that it was most useful with midfoot surgery in terms of balancing the foot. And I've often wished when I'm doing these midfoot that I had a pedobarographic, portable pedobarographic plate to assess weight distribution after I've, you know, in certain positions, because there's a few questions that people are asking about how do you judge position? It's tough. It's almost a gestalt, but you have to be aware of it and be very careful not to over dorsiflex. The most common mistake to make is to over dorsiflex the metatarsal and offload it completely. Yeah, and that's after 25 years of practice, Tim, you're saying it's challenging. And I think that when you're starting out in practice, it can be quite challenging and it's humbling too. So we're gonna take the last minute that we have and we're gonna just go through the Hollywood square box that we have here. And Mark, if you're gonna share, you know, a couple of things about mid-foot fusions with the group that we have here, what would you say? Yeah, I would tell everyone that you've got to be realistic with this. This is not an easy operation. This is a challenging area of the foot and you've got to talk to your patients. You've got to explain the chance of a non-union to your patients and you've really got to get them to understand that. The other thing is I would be careful with multiple joint fusions. I really believe a lot of these patients with multiple joint fusions, you can only fuse so many joints and if you fuse those joints with other joints affected, you're gonna transfer the motion to those joints and maybe make them feel better. So I think counseling patient on these two points are important. Alistair? You have to be really careful on your fusion technique. Cartilage is evil. It is the anti-graft. And so it, you know, you spend your time putting bone graft on the top side, you leave cartilage on the bottom side, you might as well not bother. So spending a lot of time making sure that that joint is completely cleaned out of all cartilage will improve your fusion rates and make sure you get stable fixation. I think of two joints, screws across every joint to control rotation and make sure you've got correct alignment. And if you can't put the third screw in for insurance. So good clean out and good stable fixation in the correct position. Tim? Take your time, look at the whole foot, assess the gastrocs and use every tool you've got in your toolbox to assure fusion. Balance the forefoot and don't beat yourself up, especially in the beginning of your career if you find these difficult, because they are. Yeah. I would just summarize in saying, you know, the outcomes that Alistair showed for our promise scores that we collect here, you could see sort of the person came in with some pain and functional limitations and they got a little bit better. You know, it's an 80% win. These are not home runs. And if you get somebody 80% better, you should, you know, go out and get yourself an ice cream cone because you did a good job today. So having said all that, I think that our hour is up and I appreciate the time that you all have put into this presentation. And we'll look forward to hearing any other comments. We're all available by email if you have any additional questions. So thank you very much and have a great night. Thanks everybody. Good to see you. Thanks all. Have a good night. Later guys.

foot and ankle surgeons

midfoot arthritis

diagnosis

anatomy of the midfoot

fusion and fixation

compression screws

bone grafts

foot deformities

treatment plan

research and development