Thank you, Volker. Thanks. Great to see everybody bright and early on a Saturday. And I'm always honored to be with this group. I always learn more from them. And that's the best thing about giving talks, is that you're actually learning more than actually sometimes teaching. So I am going to be talking about some PSI stuff as well as classic meal opening wedge. And I am a consultant for two PSI companies, actually. So this is the bread and butter of osteotomy, why I love the osteotomy, why I think meal wedge is kind of the way to go, my indications, my technique, and where do I see PSI going. This is why I love osteotomy. And I come from an arthroplasty background, but it preserves the cruciates. You're not cutting any ligaments out. It makes every bad cartilage procedure better because cartilage procedures usually don't work. There's 1,000 cartilage procedures, but osteotomies do work. You can manipulate slope from, you can, I always get a chuckle from that. Yeah, exactly. I should just leave that. Unfortunately, I've said that joke like three times this week. I still get a laugh. You know, we've learned a lot from our French colleagues about, you know, how it helps an ACL deficiency, how it can help a PCL deficiency. It can make a collateral surgery that's gone bad good. And then I let people jump on airplanes when they have it. And, you know, it's not versus arthroplasty. It's kind of delaying the need for arthroplasty. You know, we want to have disease modifying. You know, I learned a lot from actually Philip Lobenhofer and our European colleagues. You know, when I saw an HSS, when I was a resident, I saw zero osteotomies. And I saw a lot of 40-year-olds getting total knees on early arthritis. And guess what? They stopped doing that because they realized it didn't work. So at one point, you know, they thought total knee could solve everything. And now we're coming back. And I definitely think we have a renaissance. And we're getting more data to show that osteotomy does help. But it can go wrong. There's definitely problems. And that's why you got to take some extra training in it, you know. But I would say many of these classic things are done with bad technique. And a lot of these sometimes can be blamed on closing wedge. I'm not bashing closing wedge. We're going to hear a lot from a master surgeon. But I think opening wedge is a reliable and reproducible technique. So this is why I like it. You know, it's better outcomes, better functions. I think normalizing kinematics, it's versatile. I can manipulate slope with this as well and ease of conversion. You know, our outcomes are showing that, you know, opening wedge in 10 years is getting closer to 70 degrees. And this is, you know, older data. This is getting closer to 80%, 90% with modern techniques. You know, we know that, you know, an HGO will reduce loads in all three planes. That's really what you want to think about, right? I'm correcting the coronal plane, the sagittal plane, even the rotational plane, which we still have much to learn about. As we know from slope manipulation, right, you know, a bad opening wedge osteotomy is really good for the PCL. You know, we can all increase slopes. You know, how do we take slope away? It's harder. And this is one, I think, an advantage of a closing wedge. You can take a bigger wedge out and you can definitely reduce slope more reproducibly with a closing wedge if you want to get a biplanar correction. Biplanar meaning not two cuts. Biplanar means two planes. And that's something we have to always be careful when we talk about biplanar. What are we talking about? Are we talking about doing a tubercle cut or are we talking about two planes? And that's how I use it. We've also shown that an opening wedge is superior than a closing wedge in terms of patella-femoral kinematics. In terms of ease of conversion, you know, I saw a lot of this when I was a resident. You know, we had to do a lot of offset tibial guides because we did a lot of closing wedges that we converted. And this is, you know, this is a problem with closing wedge. With opening wedge, from a tone lead perspective, my brother likes it. He's an arthroplasty surgeon because I'm restoring tibial bone stock. And there's, you know, Dr. Hernagoo has published a lot of papers with doing an opening wedge anatomy versus using more constrained implants for big deformities. So it's definitely more versatile with opening wedge in terms of your ability to convert. You know, really when you compare the two, there's not much difference in function. I do think closing wedge is a harder conversion and a higher conversion rate. I think closing wedge is a harder operation to do. Two cuts are harder than one cut. And you can manipulate slope with opening wedge, only about three or four degrees, maybe five. With closing wedge, you can definitely manipulate slope more. So this is, you know, my indications. It's proximal tibia vera. That's where you want to focus on. You know, you want to look at a knee and you can see whether that deformity is in that knee. And that's something where you want to create that muscle, you know, that brain memory of looking at a tibia and then looking at a long neck cassette and seeing where that deformity is. And that comes with experience. You know, I have Lynn Lankin and colleagues and there are roles for more advanced corrections. You know, I don't think everything has to be done with a plate, although, you know, Al can do everything with a plate. But, you know, we use a lot of nails, we use a lot of frames. We do a lot of other stuff like that, you know, but you can definitely, you want to have all the tools in your toolbox. So here's my classic opening wedge technique. You know, I do a big medial base incision. I do a big MCL release. I don't cut the MCL, I release the MCL. I do cut the PEZ now. I always think God put the PEZ in the perfect spot to where you start your osteotomy. It's as if God wanted you to do opening wedge tibial osteotomy because he put the PEZ right where the level of the osteotomy usually should go. You know, I then, you know, I manipulate my slope with two laminar spreaders. I do gradual distraction. I get proximal fixation with locking screws and then I distally compress and I get early weight bearing. So I always want to compress through my osteotomy site, so I always over distract. If I want to get like a 12 millimeter wedge, I go to 13 and then I compress it to a 12 and that's my kind of technique. So, you know, this is just a little bit of a technique video where, you know, I'm a ranowatt, we make big incisions. I don't think you should need an oblique incision. I'm elevating the sartorius fascia, then I'm doing a big subperiosteal dissection and you got to go very proximally and you can see the PEZ tendons there. I've actually kept them. Now I usually release them more. Then, you know, you place your pins, you measure your pins. Bone does not like to be cooked, so you have to, you know, be a very aggressive irrigation. This is a two-plane cut or sometimes they'll say a bi-planar cut. That's where I talk about you want to, you can, you know, you can see the thermal necrosis. The problem with, I say, using saws is that it does cook bones. You have to be very, you know, sometimes there is a role for keeping a tourniquet on. I'm not using a tourniquet because that blood actually cools the bone. And then, you know, you stacked osteotomes. We were talking about this the other day and you have to make sure each osteotome goes in a little less deeper and you get a gradual distraction. You want to let the bone breathe. You kind of say hoop stresses, hoop stresses. I like this device and it kind of gives you your depth and how much you can open your wedge and understanding your wedge in the front and in the back, right? You know, that one to two ratio is a good place to start and you really want to be understanding, you know, wedge, how do you manipulate your wedge. And then as I said, you get proximal fixation and then I want to see how my osteotomy opens and then I use a non-locking screw distally. Here's where after I fix the plate, I pie crust the MCL. If it's tensioned, medial surgery, whether it's an osteotomy, a uni, or a total knee relies on rebalancing the knee. If you do an osteotomy and your medial side is too tight, you actually increase medial compartment pressures. So soft tissue balancing is still an important part even when you do osteotomy. And then obviously I'm looking at, you know, all my planes, sagittal plane as well. So I did that for a good 10 years and I thought, you know, I conquered osteotomy. But then, you know, I did know some complications. I know some correction problems. I start tackling more difficult cases, more slope problems. We were learning more about slope, right? When I started doing osteotomy, slope wasn't an issue. Now you can't walk around this hallway and not talk about slope. So that's got me into patient-specific guides and really it's really advanced templating. So even if you don't say, I don't need a PSI implant, I don't need a PSI guide, but digital templating is the future. And I think that's really great. Also, it can make a lot of young surgeons more comfortable, gives them more tools. So it really helps learning curves. It's much more efficient and we've shown it that. And I'll show you a paper. And obviously it gives you procedural versatility. So this is the advantage of this concept is it's a long leg cassette that can be superimposed on a CAT scan. So it's actually most robotic systems don't do this. They don't superimpose a CAT scan on a long leg cassette. So you get some functional soft tissue balancing. And then you can see if you have any joint line congruency. You then start doing your digital templating. You get all your variables in the coronal and sagittal plane, and you can decide, do I want to do a tibial osteotomy, a femoral osteotomy? Do I want to do both, right? When I started doing osteotomy, I thought double level osteotomies were insane. Now I think not doing double level osteotomies can be insane. So it's amazing how much we've evolved the field. Two smaller corrections is always better than one big correction. For multiple reasons, we can talk about manipulating the joint line, lack of healing, inter-articular fractures, and all this other stuff. So it's a streamlined instrumentation. It's a simple workflow. This PSA guide is really the operation. Once you've templated, you just got to fit the guide to the bone. It is very well contoured, and there's a little flange over the tubercle. They're calibrated drill bits. So when you do an opening wedge, it's all using drill bits. So the thermal necrosis is significantly less. My healing rates with an opening wedge with this technique is like three weeks versus it was like six weeks with the classic opening wedge with a saw cut. And it also protects you from your posterior structures, and it also manipulates your hinge axis. I can put my hinge axis anywhere I want. I can make a straight A to P for slope neutral, or I can make a small anti-lateral hinge if I want to reduce slope. Or theoretically, I can make a bigger poster lateral hinge if I want to increase slope. And as we've shown, there's less fluorotime. So you know, this is an osteotomy in a box. It's very streamlined. It's very low profile. It's durable. It's versatile, and it's very efficient. Here's some studies that we've done where we've shown that using virtual osteotomies and the anti-lateral hinge is really the only way you can manipulate slope. And it's really hard to reproducibly do an anti-lateral hinge safely without violating it, I think, freehand. We've all tried it. We've all done it. Sometimes we're happy with our slope manipulation just in the pure doing by correctional osteotomy. Sometimes we're not. And using the PSI guys helped me. So this is a study we just did. We had four pre-experienced osteotomy surgeons. We had CT measurements of wedge size, pre- and post-osteotomy alignment parameters, and radiation exposures. And we compared a PSI system to a freehand system. And we showed that if you look at the scatter plot, the body CAD system was spot on versus the freehand. And I would say high volume osteotomy surgeons was much more scattered, and it was significant in all of our variables. And this is true for any robotic application. Whenever you see a robot versus a freehand, you will see that slide. The question is always I'm going to get, is it worth the cost? Is it worth, does it really make matters with outcomes? That always remains to be seen. That will take much more time. But I'll tell you this. When I was a resident, every total knee done in HSS was done, you know, with jigs. Now 65% of every total knee and total hip done in HSS is done robotically assisted. And that number is just going up. So if we're still using bovie cords and alignment rods in 10 years doing osteotomy, I think we got a problem there. So we can't let the joint guys have all the fun. So this is, you know, the way I kind of see this problem. This is a classic post-meniscectomy knee. And he's an engineer. I love doing osteotomies and engineers because it's the quickest conversation because they're like, oh yeah, a hundred percent. Like you got to break my leg. Like it makes, I feel the load in my meal compartment right now. And then they always get mad. It's like that guy just took out my meniscus. God. So this is the easiest patient to operate on. You can see he's in various, he's got some early OA in the meal compartment. This is just a tomo fix. This is the standard thing. You don't need, I think, PSA guides to do a chip shot stuff. But then you have other patients like this who's three time failed ACL. You know, I'm not really going to get to it because I want to get to the other speakers, but this is one where I did an osteotomy slope correction, really had a small anterolateral hinge, and I actually never revised her ACL. She still likes this knee and, you know, on her fourth operation, she's like, that's enough. So that was a two point correction. So, and this is, you know, how you can, how you can adjust and you can really see that wedge. This is a one to three ratio, right? You see the posterior gap is really higher than the anterior gap. So in conclusion, I think meal opening wedge osteotomy, you know, is our workhorse. It's biomechanically sound. It's highly functional, very versatile. It's bone preserving. It's bone restoring. I think PSI is the future. It's just going to come in more and more. It's not with robots, but it's all pre-OR, you know, kind of computer technology. And I really think osteotomy should be a tool in all of our armamentariums. Thank you very much. Fantastic. Thanks. Thanks, Anil. There you go. Feel free and stand up and ask a question if you wish. Anil, run, run me through like real brief, when you have a patient that comes in with a medial meniscus tear and they have an obvious various alignment. And number one, do you get a long cassette on sort of any patient in that age? And number two, run me through how you, how you tell the patient what he really needs and how difficult it is to get that patient to understand that they need an osteotomy rather than a meniscectomy. Right. Good questions. I get a long neck cassette on every, you know, almost on every middle aged knee patient. And when I first started doing that, people at HHS thought I was crazy, but it was also for my own education. I wanted to see, you want to learn how to follow the disease. You know, if you are a cancer doctor or a heart doctor, you got to know that you have to know how knees fail so we can know when to intervene and how to potentially save them. So I get long neck cassettes in all of them. You know, for the jointed meniscus tear in a 60 year old, you know, that that's usually a tough sell for me, but at a 40 year old, then I'm going to start pushing osteotomy. It really, it depends on their actual, you know, what's their overall alignment. Is it, you know, five degrees of varus or is it seven degrees of varus? And their physiological age and their work, a lot of variables, but it's. So give me a percent. This is great. And I just wanted everyone to hear what you said because I, this reflects what is my situation. Give me a percentage of your 45 year old that has an eight degree varus medial meniscus tear that end up getting this HTL. Give me a percentage. With, so at the same time, yeah, on the first, on the first presentation, it's still low. It's like, I'd say 15%. Okay. But on the failed meniscus tear, that's like 75%. Okay. Right. So it's, it's always. That sounds good. Because there is such a thing. We have a, we have a computational model. Suzanne Meyer will show there are certain knees that are meniscal loading, and they're all certain knees are more chondral loading. And, and so it's not like everyone who is in five degrees of varus with a meniscus tear definitely needs an osteotomy. And we don't really know how to really define those two groups. And can I get a percentage from the three other panelists? But of what I just asked in your practice, Stefano, how many percent of the 45 year olds with a seven, eight degree varus median meniscus tear get an osteotomy rather than a meniscectomy? 20%, 50%? L? 100% have a conversation. And then it depends on where they want to go. So we're probably looking at about 60. David and I are saying probably 61.5%. Okay. David? 35.7%. I only ask tough questions. And any trick in this conversation? They all get that conversation. And this is a very good point, what's your, because you're not a salesperson, what's your trick to make them understand it? I show them, I demonstrate on me. I stand in the varus position, I tell them where the load is, and then I move my legs. It's simple. I stand there and say, here I'm in varus, that's where my weight is coming. And if I do that, it takes the weight and I do that. I just, I changed, I changed the weight and I get, as Anil says, as Anil says, if you have someone who understands mechanics, they go, oh, please, please do Roland. One of the question is when you take the history of these patients, because quite often it's a generative meniscus lesion, and they, it's not, that's not the problem. If you examine the patient and you understand they have not really very typical meniscal signs, because then the pain's coming from the loading of the medial compartment. And these patients, they need an osteotomy and not just a resection of the meniscus. But if they have an acute meniscus tear, twisted their knee and then sudden pain, this is something where you could try just doing a partial meniscus resection if needed, and then see how the patient goes. And then maybe, so, okay, come back in six weeks time and do maybe an unloading brace, see what will improve. But if it's coming because of medial knee pain, which is difficult to identify, it's somewhere on the medial side pointing, but the meniscus sign, McMurray's negative, you know, these are the people who need or should get an osteotomy. But that patient, Roland, as well, the one that you've done the partial meniscectomy on, if you've had the conversation about the osteotomy, if they do come back and have pain, you haven't lost, they haven't lost faith in you. They totally understand you've predicted that it's a problem, and then you can go to the next level. So I think, you know, it's all about the conversation that you have with your patients. Okay. Great. All right. Very good. Let's go to the FEMA.

medial opening wedge osteotomy

bone-preserving

patient-specific guides

robotic systems

orthopedic surgeons