All right, so let's go on just because this is great. We want to keep as much didactics as possible. Thank you guys for my disclosures are there. I will be presenting some things. I do work with BodyCAD. I'm going to quickly go over just the biomechanical and the complications. Seth did an incredible job. He's always amazing of summating like, you know, 700 papers in 12 minutes. So he did a really good job. But I'm ultimately going to set the stage of, you know, why I think PSI. And PSI to me is just a grab bag term of digital templating, patient-specific jigs, potentially patient-specific implants, and efficiency of procedural workflow, right? I said this last night in a talk is that osteotomy is still a master surgeon's procedure. A total knee in the 1970s was a master surgeon's procedure. What I always, the reason why I thought about osteotomy, my dad invented the total congenital knee, and that made it an average operation for an average orthopedic surgeon with good outcomes. And then I exploded the total knee business across the world. So I always said my charge to Seth, Al, and Armando is we want to make this an average orthopedic surgeon's operation. You know, now there's always been complex deformities. I mean, there are cases I see, I present, I'm like, I would never do that. Armando isn't, I don't, that's crazy. You got, you got cojones. I would never do that. So there's always going to be master cases, but that's the goal here. And we want to, we want to give it, because there's always master surgeons who don't, when I visit Italy, when I was a traveling resident, I saw a surgeon do one of the best knee surgeons I've ever seen, a femur, tibia, patella, and tubercle osteotomy, same patient, 46 minutes, with a cigarette. And then we had like wine in between cases, and I was like, okay, this is Italy, I love it, but whatever. It was like 20 years ago. And no, one x-ray after the end of the case. And my osteotomy surgeon at HSS, not a bad orthopedic hospital, you know, took like 45 x-rays. So there's, so we want to get that from that master surgeon to the average surgeon. And that's really the goal of this kind of thing. We talked about the biomechanical rationale. I really think of, and set the stage, you want to think of osteotomy, you want to get out of just the coronal plane, get to the sagittal plane, eventually, Alice said, which we're not fully there, to the rotational plane, and then get to the ligamentous plane. That's really, that's really, so that's what we're saying, right? Like, okay, we got coronal, down. We're getting sagittal, down, right? Rotational, we don't know. Ligamentously, we kind of get it with the ACL, but we don't really fully get it with the post-lateral corner. So that's really how, you know, what keeps me up late at night. And this is a paper, when I was a fellow at Pittsburgh, from, you know, everything we learned about osteotomy is from our Canadian colleagues. When Bob Giffen taught Chris Hunter, he was like, look, if you change the slope, it affects the ACL. This is kind of a big deal. So this was the landmark paper that I, you know, read and helped do, and that really changed my approach to understanding osteotomy more complex. You know, my only, my major disclosure is I'm a ranawat, and I don't do knee replacement. So this is why I love osteotomy, right, because it preserves the cruciates, right? Rich Comestock, famous engineer, we don't say, no arthroplasty will give you normal kinematics if you cut the ACL and PCL. They're trying so hard, but they're still not there. And now they're going to try ACL, PCL preserving, you know, total knees. But the reality is we have a way to preserve the cruciates doing osteotomy. And to Seth's point, I'm a bad cartilage surgeon. I become a really good cartilage surgeon when I do osteotomies. It makes every cartilage operation better. Hence, you don't, if you're in Europe, you don't have to do cartilage operations. You can just do abrasion arthroplasty. That probably is all you need. And then obviously, it makes you a better collateral surgeon, and then, you know, they always say about osteotomy, which I get a little annoyed about, it's like my brother would say, well, you know, 20 years, it's a conversion. Yeah, there's always a conversion. If you have a painful total knee, you know what you do? They say, here, here's some Windex, here's some Voltaren gel, come back again. If you go to a total knee surgeon, you have a painful osteotomy a little bit, meaning, well, I ran, I worked out, and my knee hurts, oh, it's because of, you had a bad operation. You got to take that out and get a total knee replacement, which doesn't help them at all. So that's always my caveat. We talked about this, you know, tibia vera is what I love. I want to correct tibia vera, and there's a spectrum of tibia vera, right? And Seth showed a big MAD. I go to, you know, I'm half Indian, I go to India a lot, and that's where you see tibia vera. And the Indian population has horrible knee arthritis because the proximal tibia is more verous than the Caucasian knee. And the worst tibia vera, right, is that Blount's knee. Understanding, right, you can just, you know, eventually, you want to get, you want to look at enough long-leg cassettes. My dad never had a long-leg cassette when he did total knee surgery, because he looked at enough APs, and he had enough long-leg cassettes that he put together, that you can eventually, in your brain, I teach all the fellows, I want you to look at a knee and say, that's six degrees of verous. Look at the long-leg cassette, okay, six degrees of verous, and then look at your AP, and you can figure, you want to get that paralyticity in your brain. And that's really the goal, to me, of preoperative assessment. Seth talked about this opening and closing wedge. You know, we wrote a paper about this. You know, opening wedge is our workhorse. Closing wedge still has a big role, certainly has a big role in other countries because of cost. You know, they can use a lot more minimal fixation. You actually can change slope easier with closing wedge. So there's certainly a role for this. But obviously, I think the outcomes, although right now, say, are close, are clearly better with modern techniques with medial opening wedge. So although historically, they're saying there's no difference, I think there is a difference. So slope was what always kind of got me going, and what got me going was understanding the hinge axis, right? The hinge axis, Seth kind of pointed on, is where we ideally want our saw to end. But the reality is, it's hard to have a saw go exactly where you want it to go. But once you start thinking of the hinge axis, and that was the attempted genius of the Arthrex plating system. Although that jig is enormous, it was trying to create a perpendicular hinge axis, but it just did it with overly engineered jig. Once you understand the hinge axis, and understand that we can manipulate the hinge axis, that's the only way you will truly understand slope. So if you have an anterolateral hinge axis, which is in the bottom there, that is the only way with an opening wedge osteotomy, you can manipulate slope. Let's see if this is, nope, that's not it, yeah, right there. So this is a paper that we did, and we basically showed that a small anterolateral hinge axis will be able to manipulate slope. Seth really talked about this. The goals of correction, I thought he laid it out exactly how I think about it, right? It's patient specific, it's procedure specific. You know, an arthritic knee and a cartilage procedure, we talked about this last night at dinner. I still like to under correct women a little bit more. I'll be a little more likely to put men into more valgus, I think women have more soft tissue and kind of ligaments laxity, so they can kind of, I'm worried about the MCL a little bit more. It all depends on how much correctable, what are they on table, their correctable varus. So there are a lot of factors that makes me think about what's my goal. And if you use advanced digital templating, realize, don't be married to your template. You can adjust your template. That's the knock, when I speak to my teachers, my osteotomy teachers, like this system is stupid, you are locked into a template, and then you're handcuffed, and I'm saying no. It's just, it's giving me, it's my ways, it's giving me all the ways I can get to Colorado Springs from the airport. But I hit the roots button, and I can adjust my roots. You don't always go with the first plan, because the more and more you guys do Waze, the more you realize, since Waze got bought by Google, it's gone way down, because we don't trust it as much. So that's the point, is that, hit the roots button, adjust your preoptic template based on what you see on table, all right? So here we talked about complications, I've had all of these. I did, me and Armando were talking last night, you know, I did maybe two osteotomies as a resident. In HSS, you got a toning replacement if you had early arthritis, and you were 45 years old, 15, 20 years ago, and those all did horribly. And now the joint guys were like, that's bad, maybe we should do something, we gotta get osteotomies or something else, let's make a new department. But I learned, I learned from my European colleagues, I learned from my Asian colleagues, my South American colleagues, I learned from a lot of people. But in that learning process, you know, it was hairy, and we're gonna get to there. And I've, you know, I've had them all, and, but it's also, you know, made me a better surgeon, and made me understand I've never had a vascular injury. We talked about this paper, there are a lot of potential complications with osteotomy. I'm not trying to scare you about osteotomy, I want you to use complications, use my complications, use our complications, and think backwards, so you can avoid them. That's really the point of master surgeons and helping you to get around that. So how do we use new technology? Well, this is what I thought about PSI, it's really to minimize complications. We use advanced digital templating for an accurate correction, because you get weight bearing, you get a jig, a PSI jig, which will afford safety, because it's drill bit technology, or you could use a saw with a golden pin that has posterior protection. It decreases your fluoro time, and it's much more efficiency, it's osteotomy in a box. And it's the only really way I can precisely manipulate complex osteotomies, I can avoid ACL tunnels, I can avoid transplant tunnels, I can avoid other tunnels with all 3D planning. So it's really giving you more procedural workflow. So this is what we're talking about, the incorporation of weight bearing x-rays on a CT scan, and a MAKO does not do that. So all their soft tissue balancing, to me, is really not grounded. Now, it doesn't really matter for 85% of your osteotomies, because they don't have that much lateral opening, so that's only for 5 or 10%, but you get this overlay of a long neck cassette and a 3D CAT scan. Then you do your virtual templating. This is kind of really cool. You can do a tibial osteotomy, I can put my hinge axis, that green dot, anywhere I want to go. I can, you know, see, I can raise my osteotomy, lower my osteotomy. I can then say, well, maybe it's too much of a correction, I want to do a double level osteotomy, I don't want to take Armando's thunder, because that's really his wheelhouse, but it can give you a lot of different things. And then it gives you all of your factors, and how much slope you're actually correcting is humbling, because you're not correcting a lot of slope. And if you do want to correct slope, how much of your coronal correction you actually have to change is a lot more than you think. And then you actually can think about slope in both the medial and lateral compartments. So it just, it's giving you a lot of information. You don't have to use it all, and not really everyone I want to change slope on, but it gives me a lot more advanced information. And then you get a jig, a PSI jig. If you ever did PSI total joints, it's only as good as the jig placement. And what we've done really, well, what this company has done, is we've put a lot of personality into the jig, so it really conforms. But you've got to spend five minutes to put the jig on right, and then it's almost an operation where you can go, start talking, and like hang out, and it's really the placement of the jig. And this company uses drill bits, and I'm a fan of drill bits, because drill bits do not cut burned bone. And since I've gone to drill bit technology, my union rates have literally a month faster, and I've never had a delayed or non-union. With a Tomafix plate, a Tomafix is a great plate, and I think you should always start your osteotomy career with a Tomafix. It's like, you don't start driving your first car with a Ferrari, you start with like a Toyota 4Runner, right? That's what, you know, or a Dodge Caravan, I actually had a Dodge Caravan, hand me down. A soccer mom. But you will eventually want to get to more and more implants, and you start your career with a big incision, big exposure, and then you can always narrow it down. But the Calibate drill bits, you know, can really make it an easy operation. The only ones you care about is these posterior cortex ones where you're by the piece, by the artery. But it really can make you manipulate that hinge axis, which is what we were talking about. And then this is what I was saying, you know, this is, it's really a osteotomy in a box, it's really streamlined and efficient. So before I look too much like a company whore, I'm going to move on. So this is really, and I actually work with, there's two or three companies that are doing this. And to me, imitation is the best flattery. If you think of like a skin patch or a regenerative patch or all these patches, there's something there. Once we go to a new field and everyone starts kind of, you know, mimicking that, you know there's something there. And that's really the point. So I'm not in any way saying one is better than the other. I'm talking more that this is, I think, something to be said here. And this is just the paper that we wrote that I showed before that an anterior lateral hinge is more likely to reduce slope. So complications I've had, I fix and avoid it, you know. So how do I think? I think about where's the failure of my complication. Is it in my indications, preoperative planning, my technique, or my postoperative care? You know, we talked about this and I think Seth did a really good job of going over all this. Just because varus, not all varus is on the tibia, just because you have varus knee doesn't mean you, it's all, you're doing a high table osteotomy. That's really kind of what you want to look at. And he also talked about if I see the MAD, if I see that joint line, the plumb line I call it, is medial, then I know it's a complex osteotomy. And I know it's deformity greater than 10 degrees, right? Once you're past your bone, you're past 10 degrees, and then if you're past 10 degrees and you're a 5'10 male, you know, you know, it's at least over a 10 degree wedge. So then you're thinking, okay, that's a big wedge. So it's just, once you get these kind of basic rules, it really makes osteotomy simpler. And you know, and this is something that Armando will talk about, but when I have a big deformity, I do a double osteotomy. This is an X-ray, when I used to use a frame, but this was, you know, a chip shot to do. And it's much easier on the leg to have two smaller corrections than one massive correction. And again, we don't want to oblique the joint line. We talked about this. Another thing, bad exposure, to me, will inhibit your ability to get a posterior retractor and inhibit your ability to really understand whether your gap is opening well and is your ab opening in the right direction. Is it a 1 to 2, which you want to do, slope neutral, 1 to 3, maybe changing the slope, or 1 to 1, which is, I call it the bad osteotomy or the only good osteotomy for a PCL-deficient knee. And, you know, and that's all based off exposure. And here's some, to me, there's two different, oh, that didn't run. There's two different ways to do exposure. There's, I'd say, the American way and the Canadian way. The American way is making a big medial flap. I release the PES, I come to the posterior compartment, and I come all the way down the leg. It was kind of like an old insole, total knee exposure. And then there's the Canadian way where you cut through the MCL with a similar, more L-flap. So there are pros and cons for both, but you really become a master of your exposure. And then understand this concept of, you know, let the bone breathe. If you go to the Mayo Clinic, when they first did non-cemented fixation in the total hip, they made the resins say, hoop stress, hoop stress, hoop stress, hoop stress. When you see somebody just whack an osteotome on their first go, you're like, oh my gosh, you have no principle about bone breathing. You know, so it's just let the concepts work. And this is just understanding that idea. And then we talked about the gap, and then let's talk about the hinge axis, right? You know, it's too flat and distal, I can come through and break my hinge axis, done that. Too proximal, can go in the joint, done that. Recognize both, and this was early in my career for both, and I over, you know, probably over-treated one, he had a large BMI, and the other one I definitely had to do, I need to get fixation to reduce that plateau. So, you know, the other thing to me is fixation. Rigid fixation is really the key. You know, you don't want to do, I think using bad plates, you know, you always want to trade your complications. That's my line. So what would I rather have? A removal of hardware or a failure like that? I take a removal of hardware three to one, five to one ratio than that. And that's why I think peak implants are dying, and I never did one, it never made sense. I want to restore bone. Why do you want to drill out and remove bone, right? And then if it gets an infection, what's the problem? So to me, you want a big plate, and the advantages of all these new systems, they're all based off the tomofix, everyone's kind of, you know, tomofix copying to a certain extent. And that to me is really understanding AO principles. You know, and then my last kind of pearl is, you know, always compress the osteotomy site, right? Get proximal fixation, and then you get your distal lag, and I over-correct my correction, and then with the principle that I'm going to compress the osteotomy site, I make a tension band technique. That is the guarantee way to get bony healing. Other mistakes I made, Seth talked about this, is, you know, I used to be really scared about weight-bearing. I'm very aggressive about weight-bearing now. I used to not use a CPM. I'm very aggressive, and I use all calcium, vitamin D, and DVT, and other things. So, you know, let's just quickly go over some case examples, and I want to get to the other talkers. You know, we talked about all the other bad things here. This is a 45-year-old obese salesman. He had a history of a failed meniscus repair and microfracture, worsening varus deformity. You can see, you know, kind of easy meal compartment, but he was a big guy. Here's his MRI, some early chondral wear. I did that, and I cracked a hinge, and I would say, nowadays, I would not do this, but this was early in my career. My dad always told me, whenever you, your first 100 total hip replacements, you put a screw in the acetabulum. Why? So you could sleep at night. This is just so I could sleep at night. He did well. Another similar case, this guy was a failed postular corner. I staged him with an osteotomy, another kind of obese manual labor. I put a couple staples across. He healed this, again, just so I can sleep at night. So understanding what plate you use and understanding lateral hinge fractures, I think if you have a robust plate, you can get away with them. If you don't have a robust plate, put some lateral fixation. A lot of times, you're treating yourself. If you ever see subluxation of the lateral cortex, that needs fixation, but if you don't see subluxation, I think, as Seth pointed out, you can get away with, you know, slow down the weight bearing, but if they're morbidly obese or other things, then what's the harm in putting some stuff? Here's another case I showed before, early in the OA. I got him to the joint, and I put a screw across, and what you want to do in this scenario is, once you recognize it, you change your osteotomy angle, and you go flatter, you know? And then you keep on going, and you see, when you're opening your wedge, opening your gap, am I opening through the joint bad, or am I opening through the osteotomy? Okay. And it was hard to assess, but, you know, for this guy, I accepted a little bit of an undercorrection, because I wasn't sure if I was displacing, once I put the screw across, displacing his osteotomy. But he actually did very well. Talk about increased slope. You know, I've done, this is a 45-year-old, he was an executive, very, very aggressive, and I had an arthritic knee, and a lot of wear, and he did not want a total knee. So here, you can see how I increased his slope. Now, I have the same x-ray, two years later, of a PCL deficiency, where I did the same thing, and the guy did great. And the question is, this is a flexion osteotomy. This is a reverse slope-changing osteotomy. This is the easiest osteotomy to do. It's so easy to increase slope. You got to pay a little bit of attention to decrease slope. And the pro that we have that, you know, Armando was talking about, is I always get proximal fixation and hyperextend the leg to get my opening gap, and I make sure my laminar spreader is way posterior-lateral to really jack up that tibial plateau compartment. So, wrong indication. This is a 34-year-old female, more of a vehicle accident. She had a failed tibial plateau. So, I remember showing this to our trauma guys, I showed this to Dean, and I was like, okay, let's do an intra-articular osteotomy. He was like, no. He was like, and he's like, I don't know how we can do it. We don't have enough technology. You know, this was like 15 years ago. So, I did a DFO. I thought I did a good correction. I thought, you know, she did well, blah, blah, blah. And five years later, she got a knee replacement. So, nowadays, I'd use PSI and do an intra-articular correction. And I wanted to, I just didn't have the chutzpah to do it. So, it's, you got to use all your available tools, and at that point, we didn't have the available tools. Another young girl, pedestrian struck during my trauma days, and she had tibial plateau. And you can see her MCL, she had an MCL repair that failed, too. And she was, I indicated her for a DFO and an MCL reconstruction. And, you know, this was the best MCL reconstruction I could ever do, because I just had to put a graft in there, and once you put it into varus. But this is where I learned, for the lateral side, the mirror image of future salvos point doesn't hold true, meaning that you want to under-correct for the valgus knee, where you can over-correct for the varus knee. And she still has her medial compartment intact, but I over-corrected her, and I put in too much varus. And she always comes, eh, my, she's very lightweight, and it's been 10 years now. She's like, eh, my medial knee hurts a little bit, and I'm like, eh, I know why. And this is another case where, and this goes to Chris's point, where this is a long-leg cassette. There's some asymmetry of her feet, and she was in a 3 to 4 degrees of varus. She had a rip-roaring, huge myelofermicondylation, which I did an OCI graft. And I would say the overlay, her, she's actually more in valgus, like her right leg, than she really is. And so this x-ray was wrong, and I didn't recognize it, and then I over-corrected her into that. So understanding the paralysis of an x-ray, looking at your other leg, is really important. And that was all based off her rotation of her leg that got me there. She still likes her knee, but doesn't love it. This is another case, non-union, I remember, Mike Schindle sent me this guy. Failed medial knee pain, multiple surgeries, and did a tomofix. This was like 15 years ago. I thought I did a great job. Maybe I got a little bit of a hinge opened up, and it was still slow healing. And I got a CAT scan. This is when I used to use a lot of fake bone stuff. Fake bone just prevents bone from, like, if you want to build a wall to make bone not grow, put in fake bone stuff. That's, you know. Now, you know, I do use Allograft now with BMAC, and I've had a lot of good success. But this was like a TCP product, and we were getting pushed all the time to use these products. Everybody was like, oh yeah, sure, it's going to heal. And I look at it, and it's like, that doesn't, it looks like I put it in yesterday. It's like four months out. So I took him to the OR, I bone grafted him, and he did great. And that's because I had a rigid plate. And he was walking on it for six months. So you know, I don't want to get too hunky-dory, but this is, you know, the use of a PSI and how it can help. This is an ACL. ACL is still intact. She had a meniscectomy as a young kid. Normal slope-ish, but her knee is not loose. It's more medial knee pain. She has an arthritic medial compartment, compartment overload. So I did a PSI guide, and this was kind of simple. So, but the reason why this was good, because a lot of times when I do it with an ACL, whether it's a primary ACL or a screw, you know, I lose a point of fixation with a tomofix. I'll lose a screw. If you do it with a peak plate, you'll lose completely your anterior screw, which is really bad, because, you know, one point of fixation. So this was a very simple osteotomy. You can see I can template my screw angles around the tunnel. It was very simple to do. And, you know, I did an OCI graft and a tibial microfracture. The only time I do microfracture is on the tibia with an osteotomy. To me, as I said, I'm a bad cartilage surgeon. This makes me a good cartilage surgeon, because she loved it, she did great, and she's back doing everything she wants to do. So I feel like I divulged too much badness. No, I'm just kidding. Like, wow, I'm not going back to an EO. It's always a sign, I'd say, of a good surgeon, if you have the chutzpah to show your badness. I think osteotomies are really a bombically sound operation. It makes a lot of sense. We know all the pros and pitfalls, and you should learn from all of our mistakes and all the mistakes out there, and then address them. You know, you can adjust slope and you can just cartilage procedure. It's very versatile in nature. I do think the PSI templating system is a way for the future, especially for complex osteotomies, but even for your chip shots. And I really do believe if you have this, you'll get less complications. And my dad's greatest line is, the eyes only see what the mind knows. So if you know the complication, okay, why is this, it's, this hinge, this gap's not opening, not opening. Well, I know, your posterior amniocortex is not freed, and if you keep on jacking open, you're going to go through the joint or go out laterally. I did that, so you guys don't have to. Thank you very much. So, any questions? James? Yeah, so, are you currently doing PSI for all your patients, or just the biplanar, complex ones, dominant ACLs? I do them from 85% now, just because it's procedural workflow, it's quicker, it's faster. My staff knows how to do it, you know. I'll still do a tomofix for like a revision for someone, you know, when I want a bigger plate. You know, if I ever have like, you know, something, you know, breaks and I don't think the plate's strong enough or something, you know, I have my tomofix on stand-up, but I'm pretty much a PSI guy all the way now. Does insurance cover that, or give you a hard time for retainers, diatomates? No, I mean, the cost of most PSI systems, a tomofix plate is not cheap in the United States. A tomofix plate is analogous to a partial knee. You know, at HSS, a tomofix plate is just as expensive as a partial knee. So, the extra cost of the system is the 3D CAT scan. And it's becoming so relevant in arthroplasty that insurance companies are not giving us grief. The last question I had is, how are you guys managing the tibial tubercle? Are you going below the patella tendon insertion and undercutting it, or are you peeling off the patella tendon off the tubercle? So, those are, I mean, I'll open up to all the podium, but one thing I want to talk about is, we used the word, me and Omar were talking about it last night, the word biplanar, like, badly. They're biplanar osteotomies, which is a traditional AO, you know, where you cut the tubercle so you can open it, and they're biplanar corrections. So, that term is constantly misused. And to the point, we should change it, right? We should just say, biplanar osteotomies when we're cutting the tubercle, and multiplanar correction, you know, something like that. So, you have to always think of the two things. That's one point I want everyone to, because it was not until like three or four years ago, and I'm like, when someone asked me to give a talk, and I'm like, wait, are you talking about correction or osteo, you know, you know, and I gave a slope talk, like, no, no, no, no, we want you to talk about, I was like, oh, well, I wish you had told me that. For me, I try to always go above, you know, the one thing I love about the PES, God put the PES there for osteotomy surgeons, because it's pretty much four centimeters at the joint line, and someone's like, oh, this is where you should start your osteotomy. And I don't mind freeing up the patellar tendon a little bit. If I'm doing enough, if I'm freeing up too much, then I will do a biplanar. I don't know, Seth, what's your approach? Other than to my PSI plan, like the metric of trying to go above the tubercle, and if for some reason, as the plan is evolving, that it makes more sense for me to start the osteotomy lower, and do the biplanar cut, not correction by the tubercle, I have no problem doing that, and I'm learning the angle now of safety with the TSI guide, because that wasn't a typical thing I was doing before. Now, I feel comfortable I can do that free hand if I had to. If you need more real estate for ACL, you can lower your side. I just think you have that flexibility on the femoral side, you know, that biplane cut gives you nice stability for your DFO, so that's also been a great thing, that anterior biplane cut for a single plane correction. I would say that's the big change, where DFOs, just all my DFOs, whatever, I don't think, were always uniplane, and now they're all biplane, you know, because of stability. Yeah. What about, Al, what about, how often do you go below the tubercle with your, with your tubal osteotomies? Correction's greater than 12 millimeters, just to really don't cause a Baja. Yeah. But, yeah, there's lots of different ways of doing things, and it's having the flexibility to be able to change it up based on your correction and your planning. Is that when you're leaving the tubercle with the proximal? Correct. Yeah, yeah. And the standard one. Right, so that's biplanar plus. On the disc. And that, and realize that is an unstable osteotomy, and that needs tubercle fixation. Okay. And, and although there's been. Relatively unstable. All right. There's a recent paper showing it doesn't make a difference out of, out of South Korea. It's probably pretty stable. Yeah. All right.

patient-specific instrumentation

osteotomy surgeries

PSI technology

biomechanical rationale

coronal plane

complications management