I am excited to see these complications, but my task here is to set the stage for us all, ensure that as we approach a framework for HTO and other osteotomies in our own practice, that at least we have solid fundamentals. My disclosures are available online. Osteotomy has been an international solution for the long time. We have our close friends and colleagues from ESCA and SLARD here visiting who grew up doing these osteotomies, and our Canadian colleagues and friends. But I think our push more recently through labs and through educational pursuits is to make this also an American solution for many of these problems. We talk about joint balance or joint homeostasis. We know it's multi-pillared, including cartilage, meniscus, stability, but at the foundation of it all is alignment. We are nothing if we cannot be alignment surgeons. I always think about alignment first, as do my colleagues. And frankly, when we look at outcomes and we compare outcomes just for these challenging knee preservation patients, if we have HTOs for medial arthritis, we have good success rates. I mean, these are 70 to 80 percent. If we think about the questions that patients want to know about return to work, those numbers are great. If they want to return to play, those numbers are also great. So I think this is an important tool in our arsenal. This is a database study that my group looked at. Over 1,000 patients, cartilage restoration, plus, minus osteotomy. Interestingly, reduced risk of reoperations, similar rates of complications, and similar overall costs if you add alignment correction to your overall algorithm. I think we need to be really honing in on this. This is for those who haven't done, or aren't doing, or are just starting in your practice. I didn't get out of fellowship and start doing osteotomies right away, and then started to take them on more in year two, three, probably did a bit too many, and then it kind of comes down a bit as the complications arise. I think for me in America, to be honest, I do more TTOs than anything. I do about 30 a year. I do 12 to 15 HTOs, that's one to two a month, and I do 10 or less DFOs, and that's pretty much my portfolio now, and that can change or grow, and I'm interested to hear what the others do. So when do we do this? Malalignment in the physiologically young, active patient associated with symptomatic mild to moderate unicompartment arthritis. Here we're talking about medial. We're talking mostly about one finger pain, asymptomatic patellofemoral joints. In these situations, you know, typically the malalignment parameters are greater than five degrees. We'll see how that change in a patient-specific way if we're talking about alignment correction in the setting of younger patients with cartilage problems or meniscus deficiency. This is from my friend I borrowed from, Bobby Doerr. I like it, breaking down when we might do HTOs versus UNIs. Maybe the panel, we can discuss this a little bit later and get your insights as well. But in general, if the age is younger, we're leaning towards HTO versus UNI. If they have more arthritis, we might be leaning towards UNIs. Lower deformities towards the UNIs, higher deformities in the osteotomy mode. Certainly activity levels, if a higher demand, we're pushing towards osteotomy. A lot of my California patients now are 60 but going on 30, and so I'm really thinking about this for them. And frankly, the osteotomy patients, they want to push it to the next level. They can endure a bit of pain, whereas these low-demand patients with arthritis want to live their daily life, just want to improve quality of life, I think that's a good patient to consider UNIs. Here's kind of that other group that we treat with HTOs, the ones with symptomatic focal defects in the medial compartment and or meniscus deficiency. When we're doing concomitant maces or ocealographs and meniscus transplants, we really cannot accept malalignment that's outside of the tibial spines. So for me, that's a three-degree correction or more, I'm thinking about it, particularly if it's asymmetric. We obviously also think about failed multi-legs, that's refractory or recurrent instability. Posterolateral and posteromedial corner issues, we can't accept malalignment in those challenging and revision settings as well. And also, as our colleagues will get into in great detail, thinking about biplanar corrections. How can we not only fix coronal, but how can we look in the sagittal plane and use slope as a weapon to increase or decrease based on ACL or PCL deficiencies? So I think these concepts of thinking about multi-planes, including rotation, are evolving, certainly in my practice and I think in our American thought process. So what are the contraindications? These are the classic ones that you see here. Al's kind of taught me or showed me if the alignment parameter, if you're looking from the center of the hip down to the center of the ankle and the weight-bearing line is medial to the knee, you have to think that it's more complex deformity, you can't just correct it in one place. So that kind of opens my eyes just for some of the things that Armando, I think, will likely get into. I don't personally do this in smokers. I think BMI is a relative thing that we think about and try to improve, sometimes using closing wedge in these more challenging patients so we can weight-bear them early with reduced risk of complications. And obviously these patients need to be compliant. They need to know what the goals are, what the expectations are. This is not a simple knee scope. This is a more involved thought process with a higher risk profile. So when we're planning osteotomies, we have to think about what is normal anyways. And it's good to kind of see this bell curve. Three quarters of the patients are within three degrees. We need to have the ability to get mechanical axis views and to be able to measure these deformities with good efficiency in our clinic. So I think looking at symmetry of varus or valgus and asymmetry, most importantly, if people are drifting one way or the other, helps me a lot. We certainly can't just look at one bone. We have to look at the joint and then look at the limb and really treat the entire patient. And so for us, luckily, there's proprietary tools now that I think Anil and others will get into. But these are kind of the measures that we look at. We need to know what normal is so we can understand what's abnormal. And we're basically looking at these distal femoral proximal tibial angles. We're looking at the mechanical axis deviations. We're looking at joint line convergence angles. We're looking in that sagittal plane, measuring slope precisely. And so I think this takes time and practice. Most of us did those osteotomy courses, I remember, with Loeb and Hoffer back in the day, getting out my tracing papers and with AO Foundation. So that is part of the basics. And now, luckily, we have software that can help us do this quickly. This is one from Aaron Critch, which scares me, a ligamentous deficient patient. This is the same patient. And you can see just different ways they load their limb can give you different information. And so it'll be interesting to talk about how we can under or overcorrect in the setting of profound ligament deficiency. But it's something to be aware of. Correcting more is not always better. You can see how the results and survival rates can fall off precipitously if you're over or under correcting for these conditions. And so this is patient-specific. For cartilage and meniscus transplants, for me, it's right down the middle. For osteoarthritis, we're talking about Fujisawa's point, as you can see here. Planning, I think we can talk about this more. I'm doing more of the PSI, but I've done this planning previously, basically involving drawing that line from the center of the hip down to the center of the ankle. That's where your mechanical axis starts. You pick your point based on your specific patient. You draw the mechanical axis of the femur. You draw the mechanical axis of the tibia. You can basically see the intersections and get that angle. And essentially, draw the line of your HTO, which is several centimeters down from the joint line. You can angle it towards the fibular head in the appropriate location. And then you can measure basically the number of millimeters of the osteotomy opening, which correlates to your angle of correction. And so again, this has become a very speedy and automated process. Those are some of the thoughts, basics, and principles that we need to understand before we just let a computer or an app do the job with or for us. Some considerations when you're starting, just be honest about your surgery time. Use a Foley if you think you're going to be three hours or more with a concomitant case. I don't do it for routine osteotomies, but I will do it for combined cases. Make sure you're obviously padding all the other locations so you don't get neuropraxias in some of your longer cases. I don't typically use a tourniquet for these cases, but I think some of my colleagues do. We're more and more using TXA. At least think about what's going to happen if you have a complication. Do you have a blood bank? Do you have a vascular surgeon? Do you have to, like my institution, pack things up and transfer them to the main hospital? So think about that before you go, and then hopefully you never have to act on that. I keep patients 23 hours typically. I drain them overnight for this and other big surgeries. I never regretted putting in a drain. Compartment checks, I check all these patients myself after the surgery and before I leave for the day. I do typically either adductor motor sparing blocks or sometimes femoral blocks and again the short stays. So let's just go through what are our options for Varus. Lateral tibia closing wedge osteotomy is an option. Any closing wedges have good healing, early weight bearing. There are cons here. The surgical dissection, difficulty with closing wedge of getting that precise correction, particularly if it's not patient-specific instrumentation. You can disrupt that tib-fib joint, may need a fibular osteotomy. The perineal nerve's obviously on the lateral side. You can shorten the limb. And so this list is pretty long, but it can be useful for some of those more challenging patients. But in general, most of us, I believe, for correcting Varus on the tibial side are doing medial opening wedges. Here's kind of what this looks like. We all know the familiar surgical dissection and the ability to titrate your correction after the osteotomy. We do have issues with prominent hardware that might need removal. We do need to limit their weight bearing, at least in the first several weeks. We'll consider bone grafting if it's a greater than 10 degree correction. And we'll go through the issues with fractures and or non-unions. This I just put up here because the information's evolving. There's some papers out there comparing peak versus plate. I don't use the peak implant much anymore. I probably chose poorly and had a few patients that either I had an infection in a larger patient that I clearly regret having peak and not metal when I was managing it. And I had one also that fractured, probably a technical error on my part. But I think in general, if you look at the literature out there for the peak versus plate, it's less prominent. You can actually put your MCL repair over the top of it. And so there is less risk of hardware removal. I'm excited to hear my colleagues' thoughts on peak versus plate as we go through the discussion. Avoiding complications is an article that Al and I wrote I think a year or two ago with our fellows. Basically we're trying to avoid this, that dreaded pop in the OR with HTOs specifically. But it could also happen with the hinge and DFOs. I think this gets to paying attention to details, knowing where your safe zones are, thinking about ways that our industry partners have tried to protect the hinge. That's one way that you see on the left, basically putting a bolt in at the location of your hinge so that you really can't move your saw further. There's also evolving ways to put these golden pins. Or now some of our colleagues are actually even putting screws in as hinge protectors. So this is important and a technical detail that I think we should all be thinking about because hinge fractures can and do happen. If they do, classify it as you see here. Have a plan. Don't scramble. In general, if you have some minor propagations without displacement and you have a very sturdy plate, you might be able to just get away with changing your weight bearing status. I think it's always easy to just go to the opposite side and try to use either a staple or put a screw in. But you don't want to think about this at the time. You want to think about this beforehand and have your plan ready. And then if it happens in the percentage that it might, then you just move forward and you don't worry about it. We'll talk about protection of the other soft tissue structures, patella tendon, that's obvious, MCL. I think we might manage it differently. And I think that that is something that the devil's in the details, particularly when we get in the lab and see each other work and see the high volume osteotomy surgeons, how they're managing the medial soft tissue structures. We always think about the nerves and vessels. So in my plan, I put on the problem list, is there an aberrant tibial artery? I look for it every time. It's likely seen you, but have you seen it? And so if you look for it, you'll find it. It may even alter your plan. I think Andres Gamal from HSS, our good friend, has aborted some plans when he saw that too close to the back of the tibia. But I think there are workarounds. But if you don't know it, you're going to get burned by that one day. And that's about 2% incidence. And you can kind of see it here. Instead of being nicely protected by the musculature, it's riding right on the back of that tibia. So when you see that, that's pretty scary. And you should be aware of it. This is also from Al. Don't change the slope. It should be a 2-to-1 relationship from back to front, unless you want to change the slope, in which case we can affect change in the sagittal plane to help with ACL or PCL insufficiency. Patel femoral doesn't really get as much airtime here as far as issues in high tibial osteotomy. But certainly, we can create Baja with medial openings. You can have degenerative changes. And this is more of a problem with large corrections. Again, you can put this into your plan. There are workarounds, ways that you can manage the tibial tubercle to try to reduce this problem or risk. But I think in the majority of cases, even if it's low-grade Baja, it's typically not an early or mid problem for these patients, but something to be aware of. These are kind of just the rates of all the other bad things that we think about, DVT-PEs, infections, delayed and non-unions, and the groups that have the highest risk. And this follows a similar profile to other large cases. Conversion to totals can be technically demanding. Outcomes are controversial. But in general, similar survival rates, scores, and radiographic results versus primaries. However, the OR times are longer. There's higher risk of infection and reduction of range of motion. So I don't do totals. If some of our colleagues do, they might weigh in on that as well. And just to round this out, and then these guys will show some case examples of how we manage specific patients, there's also the ability to do lateral opening wedge HTOs. You can do this for small correction valguses, particularly if the distal femur is normal. This will affect change in both flexion and extension whenever you're doing something on the tibial side versus doing a distal femoral osteotomy, which really is only affecting change in extension. There's literature to support this as well. And because we're talking about osteotomy on the top of the tibia, HTO medial opening is our workhorse, as we said. Lateral openings can be done. Medial closings can also be done for these small corrections. Just have to make sure that we don't run into issues with joint line obliquities. But again, there's literature support for these techniques. Neal's going to go deep dive into 3D printing and the pros and cons for this. I will just add my two cents at this point, that this has really changed the game for me, not only in the execution and precision of my osteotomies, but also in my ability to pre-plan and think in multi-planes and really to learn and evolve and take on harder cases that I might not have done before, like this patient with failed ACL and failed medial meniscus transplant. They have instability. They have asymmetry of varus. They have frank medial arthritis at a young age. They also have increased slope. And this is something I might have staged in the past. But with planning where your ACL might go, planning of your correction, single cut with a two-plane correction based on where your hinge point is, a concept that I've learned and use fairly frequently, we can get good results. And so hopefully my overview has helped to set the stage for what will now be interactive and case-based discussion. Obviously, alignment's critical. That's why we all got up early today. Osteotomy is an extremely powerful tool when used correctly. Techniques vary based on patient factors, concomitant issues, the amount and location of our deformities. We're here because we're trying to avoid these complications. And we can do so or at least reduce them with thoughtful pre-surgical planning, meticulous techniques. This is from Bernie Bach. Like your patients, but love your complications. Everything that Anil said about what to do in the setting of a complication has kept me out of trouble. I doubt his dad had a cell phone back then, but maybe gave him a quarter. But at any rate, I give these patients my cell phone immediately. They need access to you. They need a good plan and support system. And as I said, keep the pulse on the evolving technologies and techniques because they've changed my practice. And I hope they help to change your osteotomy evolution. And thank you very much for your attention.

osteotomies

high tibial osteotomies

knee preservation

alignment correction

medial arthritis