Thanks, Rachel, that was outstanding. I love topics in knee joint preservation and learn every time we go through these ICLs. So my task here is to talk a little more detail about osteotomy in the interest of time, because I think discussion in cases are as or more worthwhile. The focus mostly on the femoral tibial joint. I hope some of you joined us for the osteotomy patellofemoral before, and we have a full patellofemoral session that some of us are involved in right after. My disclosures are in the program. Osteotomy has long been the international solution for a lot of problems. And we're trying hard now to make it an American solution. So I think, as Armando talked about, this is something we all need in our armamentarium, and it helps us to solve many, if not all, of these problems. We always think about cartilage, meniscus, and stability, but alignment is also a very large and bolded part of my Venn diagram to achieve joint homeostasis, which is the overall goal, a nice, balanced joint that is able to have no or minimal pain and improved function and quality of life. That is the goal of these procedures, not necessarily always returning to the highest level of impact, contact, or collision sports. Osteotomy can be and is a workhorse. So there's data to support it, and it's right in the range of everything else that we do in the space. So if you look at HTO for frank arthritis, you can see success rates in the 70% at longer terms, up to 10 years. You can see DFO outcomes for frank arthritis. Similarly, you can see good survivals and improvements in knee function. Osteotomy outcomes here, we're looking at return to work and return to play. Again, those are as good as most of the options within our armamentarium for cartilage restoration. And so it is important to understand whether you have to do more than just correct and unload. This is something we just published in Cartilage, big database study. And actually, when you add osteotomy to your cartilage repairs, so Macy or osteochondral allograft, we have reduced risk of reoperation, similar complications, and similar cumulative overall costs. So it might be counterintuitive since you're doing more, the morbidity might be higher, you're more worried about the risks of reoperations. But in fact, it's protective and should be included in this algorithm. This is important for those who may not do this a lot. This is my learning curve, so it's not like I went out into practice and started doing the 60 osteotomies that I averaged before I moved practices. It took some time, and I think you should have patience and really do the slam dunk cases first before you start implementing osteotomy. And then I think you'll get to a reasonable average just for perspective and we can talk about it. For me, I do about 25 to 30 tibial tubercle osteotomies in a year. I do about 12 to 15 high tibial osteotomies. I do sometimes more, sometimes less than 10 distal femoral osteotomies. And it'll be interesting to hear what the others do as well. We've talked about patient selection. These are physiologically young and active patients associated with either mild to moderate unicompartment arthritis, so that's medial lateral compartments, and asymptomatic in the patellofemoral joint. And for those patients, we're typically correcting malalignment that's greater than five degrees. This is a nice slide. This is from Robert Doerr, who's also talking at this meeting. And it just breaks down kind of some of the factors, uni versus HTO. I think for us joint preservationists, some of us might do unis. We need to have this in our head, thinking about age, thinking about KL grade, amount of deformity, activity levels, and putting it all together. And seeing osteotomy on one end of the spectrum, the younger, more active, mild or no arthritis, bigger corrections, whereas the unis are a little bit older, more sedentary, maybe higher grade arthritis, maybe they're really just going for pain relief with normal stuff, and they're not trying to jump and run up mountains all the time. And so I think that's just a good thing to keep in your mind. It's definitely helped me in that discussion. I'm typically seeing patients that are HTO versus uni. I'm not typically seeing patients that are uni versus total. So I think having PFJs and having medial unis in your armamentarium is reasonable if you're going to be doing this. There's this other subset. So these are the patients with focal defects, meniscus deficiency. They're ones who might need cartilage or meniscus transplants. And for me, my thresholds are kind of three degrees here, and so a bit lower than the arthritis subset. And then we have even other subsets like refractory or recurrent ligament instability. So if you have chronic and or failed posterior medial or posterior lateral corners, then you definitely want to think about realignment in those types of cases. And then something that I think us on the podium have been doing more now that we're learning about patient-specific planning is trying to tackle these biplanar corrections. So these are tough patients with tough problems. They've failed ACLs. They've failed PCLs. We look at their sagittal alignment. We look at their tibial slope. If it's too high, we consider decreasing in certain scenarios. If it's too low, we consider increasing, for example, in PCL deficiency. And so that's become a big workhorse for me as well when these challenging patients come in with two or three failed other surgeries. The contraindications are typical range of motion loss, flexion contractures. Think extremes of malalignment. We have to think of multiple plane alignments or other ways to do this, and complex rotational multiplanar deformities, syndromic patients. We all have limb lengthening colleagues that do frames, and we should think about them, especially previous major traumas, compromised soft tissue envelopes. So really use your partners when necessary. But I don't do these on smokers. I try not to do them on BMI greater than 35, although I think it's reasonable in certain scenarios. And with all of the things we're talking about, compliance with rehab and really managing expectations is the critical, critical component to success here. So we take more time talking to these patients in the clinic than any other. I push them away, treat them non-operatively, get a flavor for them and for their knee. I bring them back. I counsel them effectively. We try various things. We fail. We do a staging scope. We have a plan. We sometimes execute that plan. So this is not the knee jerk. Let's just go to the operating room. I have a tool, and I can fix you. That will get you into a lot of trouble in knee joint preservation, in my opinion. We need to understand that there's a bell curve of normal. I think the key point here is that your long leg views, as Armando said, are hugely important. And I look for symmetry versus asymmetry. I'm much more inclined to correct malalignment if I know that it's decompensating. So if it's an asymmetric malalignment. So here we can measure that deformity, and you can see on one leg the mechanical axis passes neutral. The other leg, it's passing through the lateral compartment. I want to know if that's physiologic. I want to know if it's pathologic. I personally have not corrected someone back into varus, but I've seen Mike Bamfy showed me a case where someone started varus, drifted way into valgus with significant lateral compartment disease, and he corrected that. And that patient at over two years is doing quite well. So interesting food for thought. And then I think, and especially with the newer software, we can get all these numbers and get them easily without having to sit down for a half hour and measure them. So we should know what's normal as far as the lateral distal femoral angles, medial proximal tibial angles. We should look at the joint line convergences. We should look at the rotational profile. And the more that you do this exercise, the more you'll really get a flavor for the patients. And we'll actually correct deformities at the site where they're supposed to be corrected. Now we have workhorses where we typically go, and that's okay. But we at least want to know what's within normal and what's an outlier. This is a concept I still don't really fully understand and wrestle with. When you have these patients with ligamentous instability. This is from Aaron Critch. And you can see how it's really gapping open laterally. However, if you pay more attention and put that knee in a slightly different position, it closes down. And so is there truly a major bony deformity here? What are the implications for correction? Are you at risk for overcorrection? The strategies to deal with this are evolving. More is not always better with correction. This is a study from Andreas Gamal, our good friend, who's showed that really if you put them into too much varice valgus outside of the mechanical axis, the rates of drop in survival curve are substantial. And so the parameters and the numbers that I talked about for arthritis and for joint preservation I think are what we're typically using at this point. And so it's patient-specific. So if you're starting here for cartilage restoration, I'm going between the spines. If you're starting for meniscus transplant, I'm going between the spines. If we're talking about osteoarthritis, we can go all the way to that 62% if we want to. But I'm typically going to the kind of downslope of the lateral tibial spine. I'm interested to hear what the others think about that as well. Pre-op planning. There's different ways to do this depending on your system and set. But you want it to be consistent and reproducible I think is the take-home point here. We'll go through some of the surgical exposures. So this is for valgus. We have the distal femoral osteotomies typically. That direct lateral approach or a medial subvastus approach. So medial is the closing wedge and lateral is the opening wedge. For varice, we're typically doing the high tibial osteotomies. So medial approaches, opening wedges in general. And we'll talk about that in detail. Sorry about the titles here. I'm not sure what happened in the transition. But at any rate, we use fluoro. I use large fluoro. I don't really have a great role for the small C-arm. I set it up pre-operatively. Really know whether you want the fluoro on the operative or non-operative side. I actually have a thing on my pre-op sheet where I think about it and if I'm doing something, let's say including an MPFL, then I want it on the operative side. And there are other scenarios where I want it on the non-surgical side. If I'm doing an HTO, then I really want it coming in from the lateral side so that I can work on the medial side, et cetera. So be thoughtful about where your fluoro is in your room. You want to be honest about your surgical time. Don't be afraid to use a Foley during these cases. Pad all the important places. I typically am helping my team prepare for these bigger cases. I don't use tourniquets except for ACL graft harvest and that's pretty much it for me. I definitely implement TXA, similar to the joint replacement doctor strategies. I think it's important to have a plan for your blood bank or vascular. They don't have to be readily available for these cases. But I'm telling you, if you're a high volume osteotomy surgeon, there's going to be times where you need your friends. And so know how to get to them. And then drains, I think, are a reasonable thing. Some of my patients actually now leave that same day or stay until like 10 p.m. Others stay 23 hours. I prefer that. I like to watch for compartments and for pain, and I just take the drain out before they go. And then compartment checks, I'm typically using selective catheters. So that will either be femoral catheters or adductor catheters. I'm not really doing any IPACs or any other posterior blocks. And here are the options for Varus. So we have a lateral tibia closing wedge osteotomy. And the pros would be good healing for any closing wedge and you can weight bear on it, which is really nice. But the cons are that it's hard, there's a big surgical dissection, hard to get your precise correction. And these are consistent themes with closing wedge anywhere you go. You do have to disrupt that tib-fib joint, fibular osteotomies, the perineal nerve, shortening the leg. And so you can see why this has not caught on with any significant volume in an American surgical population. These can be used in those larger BMI, smokers, if you need large amounts of bone graft for something else. But really, medial opening wedges are what we are all typically using for the vast majority of Varus corrections. And you can see this here, it's less dissection, preserves the tib-fib joint. We can titrate our correction after the osteotomy. It is prominent hardware, so you counsel your patients that they do have a real rate of removal of hardware, somewhere in the 20 to 30%. But I think some people routinely remove their hardware. We do delay weight bearing. You do have to bone graft if it's greater than 10 degree correction. And we have a risk of fracture and nonunion. Peak versus plate. At this point, there is evidence to support the peak plates. And the removal hardware rates are lower, and the outcomes are the same. I'd say if you're going to use the peak plate, I would cherry pick and do the easiest patients possible. The chip shots, the thin, the relatively smaller corrections, and start there. I would not start with patients who are more complex than that. And then we're all thinking about complications. Fracture is one of the major complications. Protecting the hinge is the theme. There's many ways to do this with each of the proprietary systems. So they're all paying attention to ways to protect that hinge while you're making your osteotomy cuts. Have a plan if you fracture that hinge. Al Getgood and I wrote an article last year just detailing the management going from type 1, 2, and 3. And this was covered yesterday as well. But in general, for some of the small, non-displaced cracks, you can either limit your weight bearing, or you can, if you have locking plates, you don't really need to go to the lateral side. But if it is displaced, I think having a toolbox that will allow you to put screws in or put staples or do whatever is necessary so that you can leave the OR comfortable is really, really important. Neurovascular protection. This is also of concern. It's rare, but it's catastrophic. Many of the systems also have built-in neurovascular protectors, which is quite nice. I think getting used to the dissection around the back, being able to shuck the fibular head with your hand is very important before you do your HTO. And so I don't start any of my cuts or put in my retractors until I'm totally clear in the posterior aspect of the tibia and can feel the fibula. This is something that I think is very important that I'm not sure I noticed early. You should look for this on every axial image, whether there's an aberrant anterior tibial artery. You can see it on your slices. And basically what happens is that it closely hugs the bone, and it can be at very high risk during your osteotomy. And so we can discuss maybe whether we want to pivot to a different procedure if you have an aberrant artery, or if you just want to have meticulous peeling of the periosteum and staying away from it. But nonetheless, better to know before you go. And there you can see a picture of it right behind the tibia, which in most cases it's usually protected by the musculature. And so don't change the tibial slope unless you want to. So it should be 2 to 1 from back to front. If you make it a 1 to 1, then you know that you have increased your slope. And so you can do that effectively if you're choosing to for a ligament problem, but otherwise you really want to pay attention and not do that. And then I'm always thinking about the patella femoral joint. Patella baja is a risk with medial opening more than lateral closing. It was just recently looked at. Degenerative changes in the PF joint are real. They may be more of a concern with opening wedge and for large corrections. And so I would just say, measure your patella height with Catan de Champ before you start. If you have large corrections, then you may want to do your HTO a little bit differently. And there are a variety of ways. You could always take the tubercle off and put it back on if you wanted to, or you can use a hinge on the bottom side of your tubercle so that the patella tendon stays with the proximal metathesis and the joint as you do your HTO. But it's important to know DVT, PEs, infections, delayed unions, non-unions, again, are there with some prevalence. So we need to educate our patients, but they're fairly low risk. I'm not using anything more than aspirin these days for DVT prophylaxis. Conversion to totals, I don't do this, but they tell me they're technically demanding because of scarring, hardware, tendon mobilization. Outcomes controversial, but in general, similar 10-year survivals, outcome scores, radiographic results, longer OR times, higher infection risks, and reduced range of motion. But I think that the old rap that you can't convert effectively is just not necessarily true. And then for valgus osteotomies, the lateral opening is the easiest. It's one cut. You can titrate that correction. Stable locking impants, but there's hardware issues with the iliotibial band. You may need plate removal, may have issues with some loss of correction. Medial closing is much more stable. There's soft tissue coverage. It's just harder to do, and I think some of the patient-specific planning has allowed me to do some medial closing wedges, both on the femoral and tibial side. It's given me more confidence to expand into that area. But I think that's still a work in progress. You'll have this in your handout. Again, different reasons to choose, but it's similar. Larger patients wanting to weight-bear earlier, maybe concerns if you really need to do a smoker for some reason, and all the other considerations we talked about. This is important. There's much better stability with a biplane cut. So if you're doing these osteotomies, consider adding that biplane cut, not for correction, but for stability as you heal. And it's actually not terribly hard to do, and the times to union are shorter. Hinge fractures can happen on the lateral side as well. Interestingly, I learned DFOs really don't unload in flexion. They only unload in extension. And so if you have high-performance athletes and you want to offload their compartment on the lateral side, that's where we really start considering either lateral opening wedge HTOs, as you can see here, or you can also consider medial closing wedge HTOs. We just have to be aware of joint obliquity and only do this for small corrections. But there's literature support for both of those types of procedures. And then lastly, patient-specific osteotomy. This is where you have CTs. You send them to a laboratory. You can pre-plan your deformities. And when you get comfortable through this learning curve, you can actually extend into cases such as combined HTOs and ACLs and adding meniscus transplants and other things in a much more facile way. For example, patients like this, repeat revision ACLs, medial meniscus transplants, they have functional instability, asymmetry of varus, medial arthritis, increased tibial slope, so a lot of things going wrong here. And I can do, which I never would have done previously, a single-stage revision, biplanar HTO to correct slope, put them to neutral, and then revision ACL reconstruction. And so hopefully I've showed you that alignment's critical component of knee joint preservation. Osteotomy is a powerful tool with proper patient selection. Techniques vary based on patient characteristics, concomitant issues, the amount and the locations of your deformity. Strive to avoid complications with thoughtful preoperative planning and meticulous technique. You need to like your patients and love your complications, as Bernie Bach has taught us, and we celebrated his upcoming retirement last evening. And please keep your pulse in this patient-specific instrumentation. I think there are many potential benefits over traditional techniques, and I know for me it's really been an absolute game-changer, so I look forward to that learning curve with you all. And thank you very much.

osteotomy

knee joint preservation

joint homeostasis

arthritis treatment

patient selection

surgical techniques