Okay, so my disclosure is not relevant whatsoever to this talk. And to start out this talk, the answer is yes, you should think about osteotomy and you should have it in your repertoire, in your practice. So if you look at ACL reconstructions, the revision rate is high, you know, these numbers are actually low over here. Depending what study you read, you're going up to like 20%, especially young patients and returning to pivoting sports. So and we're talking here about re-revisions. The failure analysis, as you all know, is mainly technical issues, tunnel location, graft choice, and so forth, and missed concomitant pathology, which often just gets thrown into the quote-unquote biologic arm. So we talk a little bit about that. Now if you talk about high-grade instability and all the reasons why this could be, the lateral capsule and antilateral ligament have been discussed quite a bit. So all these layers work synergistically. The capillin fibers and capsule osseous layer, they link the supracondylar region of the femur with the antilaspect of the tibia. But it's really the IT band. So if you have a rupture of the IT band, yes, fix it. But think about how many cases you truly have a high-grade lateral injury. Not too many, I would say. Now the bone morphology obviously plays a role when we're talking about the tibial slope. Think about the femur, though, also. The femur has many, many different shapes. And when you have this clunking type of pivot shift, there's something on the femur that kind of drives into the tibia and makes that clunk happen. But if you have an increased lateral slope, it's associated with ACL injury. That's been studied. And also, if you have an increased lateral slope, there is increased high-grade rotatory instability. Meniscus. This is a paper from Al here. So on this MRI, there is no posterior horn of the medial meniscus, which effectively increases your slope, right? Because there's no bumper in the back. So in those high-grade unstable patients, think about meniscus and potentially meniscus transplant. Here's a study from Bologna. All the different risk factors in multiple ACL revision patients, and it even starts with the hip, a cam-shaped femur, greater anterior tibial subluxation, which again is linked to the slope, and also previous partial meniscectomy. So here's some of the indications. I know everyone always wants to talk about what are all your indications. The general indications for osteotomy, obviously, are the isolated malalignment, especially the varus. A malalignment with OA and instability, and of course, the combination thereof. Some of the expanded indications include chronic ligamentous instability, the double and triple varus knees. And then when you talk about ACL reconstruction that's failed twice, I think we all start listening. And I'll show you some cases at the end. And so when you look at this graph on the lower left, the anterior medial part is where you're doing all of your osteotomies, right? So if you do it in that area, you will increase the slope. That's just a fact. So if you have an ACL-deficient knee, you must go posterior. So on the right lower picture, that picture A, that's very hard to do because the MCL is there. Everything is tight in the back. So it's really difficult in the opening retch osteotomy to decrease your slope. It's possible, though. These are the general options. The closing retch, a little bit forgotten these days. I think Al is going to bring it back. The opening retch, very popular, but it's hard to really decrease your slope with that. And then the pure deflection osteotomy, which we'll show on Saturday morning. And I have a short video about this here, too. The two studies that are out in the literature have a combined total patient count of nine. So there isn't very much in the literature yet. I think these are very good studies to talk about in the absence of high-level evidence. And so David Dujour very masterfully does the osteotomy proximal to the tubercle, which is not all that easy to do. There's very little real estate. And then Sonny Cote lifts up the tubercle and goes through it to do this osteotomy. So for the anterior closing retch, the so-called deflection osteotomy, recurrent instability after ACL revision, neutral leg alignment, and then when the slope is greater than 12 degrees. And then you shouldn't do it, or at least take into account, if you have a knee that has already hyperextension, you'll increase that. So be careful with that. If you have somebody with a big varus deformity, well, then you need to correct that first. And of course, the grade four arthrosis. These are the two outcome studies I just mentioned. So the slope was corrected, respectively, from 14 to 9, or David overcorrects it to about 5 degrees. So that is also a question. We can discuss. Here's a study from Germany, 22 patients, about a three-year outcome in a staged fashion. And they had good outcomes. They also overcorrected. Not overcorrected, but tensioned it quite tightly, and had very little complications. Here is for primary ACL. So I currently don't do this, but this was recently published. So 18 patients that were primary ACL deficient had a high slope and immediately had that change. So something to consider. Here's what you need. Obviously, your osteotomes, retractors, there isn't really very much to it, osteotomy spreaders, saw blade, and then some sort of plate system, whichever you want to go, but I use anything that has a rigid fixation. I'm going to go through this video, and then you can just stop me if it takes too long. But so basically an anterior approach, medial peripatella. I'm going to go just a little bit forward here. What we do is we expose the anterior compartment here, put a Hohmann retractor in it to protect the perineal nerve. Go a little bit more. Lift off the MCL. I think that's very important. After that, you can put another Hohmann retractor on the medial side. I do lift up the tibial tubercle, and once the tubercle is elevated, you then have a lot of real estate to do your pin placement. This is where the future screws will go in, and then here's where the pin placement is. So once your pins are in the desired position, take a fluoro shot, and then I put two sets of pins in the desired amount of correction. If somebody comes in with a 15-degree slope, my goal would be probably to go around 5 degrees, so it's about a 10-millimeter closing wedge osteotomy. In this particular case, we went basically with two parallel cuts almost. So if you do that, you may need to work on the posterior cortex a little bit to get that reduced. I'm going to jump just a little bit forward here, just like this. On your osteotomes, you will finish your osteotomy that way, again, with careful retractors. Those retractors that are radiolucent are helpful in this case. And once this is removed, you simply hyperextend the knee, and if you left enough of a posterior cortex, not too much, not too little, you know, that's always the tricky part with the closing wedge, then you can reduce this. Just like that. And then your fixation can be really any plate. For rehabilitation, so it's a closing wedge, which is quite stable, but the first four weeks I kind of go slow. Non-weight-bearing or toe-touch weight-bearing, then increase from there, usually return to full activity somewhere between three and four months. Complications, this is a beautiful one. A fellow that's over there knows this case because this is a current case. So obviously you have wound complications. You can have vascular complications. The under- and over-correction is real, so especially with varus, of course. But if you valgazate somebody too much, for example, people hate that. Bone union, I haven't seen in the deflection yet, but all these can happen. So here are just two cases real quick to wrap this up. So this is a patient who was sent to me that had three failed ACL reconstructions, a hamstring, a BTB, and a contralateral BTB, all failed basically rapidly from a simple stair-walking mechanism. So something is off. The x-rays, you can see the high slope. Now, of course, if you're looking at your failure analysis and you can pinpoint it on one single thing, you're very happy. That's usually not the case, right? There are multiple factors. So maybe the tunnel a little bit anterior, I think graft choices, all three are good graft choices, so that's not the cause. So something is missing. In this case, I think the slope definitely played a role. We did a revision ACL with a new posterior tunnel, lifted up the tubercle, here's the plate, and then corrected him a good 10 degrees. Here are just some images, so this worked for this patient quite well, had maybe an additional two or three degrees of hyperextension, which he does not complain about. One last case here, another patient of multiple failed ACL reconstruction, a hamstring, and then two allografts, so you could simply pin it on the allograft, but has good range of motion and complete instability, no posterior horn of the medial meniscus, so you see where this is going. So you can see on that lateral x-ray how far the tibia is anteriorly subluxed. You'll never get that reduced with a graft, doesn't matter how tight it is. The only way to reduce this is to change the slope. Now we did this in two stages, so osteotomy first in this particular case, and then in a staged fashion, this is on the right, an over-the-top allograft. You can criticize me on it, but over-the-top, I like when the tunnel is half in, half out, and then a meniscus transplant on top of that, so that worked in this particular case quite well. Again, you see just a little bit of hyperextension, but not clinically important for this patient. So in summary, assess the patients, very critical, all the intrinsic factors you need to figure out. The slope does affect the instability and predisposes to an ACL. Always investigate long cassette x-rays, CT scan, MRI, all the good things, and then slope changing osteotomy I think is useful, so you should probably have that in your repertoire. Thank you. Volker, you said that you're not doing this in primary ACL reconstruction, and I think we know why, but maybe can you just give us a bit of an overview as to why you would not do it in a primary? So there's probably a number to this, right? In general, I would say no, because the young kids, they want to return to sport, it's going to be very hard if you return somebody to sport, and then they have a complication after osteotomy, plate failure, what have you. So I really don't think that is the way to go. If you do a well-done anatomic ACL, and by anatomic I simply mean posterior to the intercondylar ridge, right? So it doesn't matter high, low, we discussed it this whole week at the Herodicus meeting, it just has to be posterior. You can overstuff the notch, if it's a small notch knee, very common, 11mm notch, don't put a 10mm graft in there, it's going to re-rupture. Fix the meniscus, do a good rehab, I just don't think you need to do a slope osteotomy in that setting. Great. And in regards to revisions, at what stage, you said sort of your second revision, what about doing it in a primary revision, or are you doing, sorry, first revision, are there any indications where you did in that first revision? Yeah, I mean, you think about it very, very hard. If somebody has a 15 degree slope, and for sure, if they have a first, they come to me with a first failure, could be my own too, obviously. They have a 5 degree varus, well now I'm probably going after this, right? You get the varus corrected, you know, get the medial meniscus fixed, replaced, what have you, and at the same time you correct the slope, but primarily the varus.

osteotomy

ACL reconstructions

revision rate

concomitant pathology

slope-changing osteotomy