Good evening. Thank you for joining us tonight for the AOSSM Fellows webinar, Revision ACL, with moderator and panelists, Drs. Volker Moussal, Jeremy Burnham, Eli O'Kane, and Armando Vidal. Dr. Moussal is Associate Professor of Bioengineering and Orthopedic Surgery at the University of Pittsburgh. He is Program Director of the Sports Medicine Fellowship, Medical Director at the UPMC Rumeny Sports Medicine Complex, Co-Director of the Orthopedic Robotics Laboratory, and Co-Head Team Physician at the University of Pittsburgh. I will turn this over to Dr. Moussal to begin and introduce the panelists. Thanks Meredith. Welcome, everybody. Thanks for joining in tonight, so we have a great lineup for you. We'll try to keep the presentations around 10 to 12 minutes so that in the end we have a discussion session. Please put the questions into the chat box and we'll try to answer them all as we go. So we have a great panel today. We have Jeremy Burnham from Baton Rouge, and Eli O'Kane from Birmingham, and we have Armando Vidal from Wales. So I think the topic is really broad. It's around revision ACI reconstruction, and we'll keep it fun. We'll talk about grafts, we'll talk about lateral procedures, osteotomies, and how to manage the tunnels. So without further ado, Jeremy, if you would start with the first presentation. Okay, can everybody see my screen? Yes. Perfect. All right. So I'm Jeremy Burnham. I'm in Baton Rouge, and I'm going to be talking about revision ACL reconstruction from a graft choice standpoint. I do receive some educational support and speaking fees with Arthrex and participate in some research funded by the DoD. And certainly I want to give a shout out to my mentors that taught me many of these things and are responsible for me being here. And what I really wanted to start off was with the patient case example that may make it more applicable to the patients that you'll be seeing in your practice. So this is a patient that came into my practice within the last year. It's an 18-year-old female high school basketball athlete. And she came as a new patient, and she was having instability events where her knee would buckle and give out on her when she was running up and down the court. And this happened at least on a weekly interval, but sometimes was happening even daily. And she would have swelling and have to sit out for a few days. In a relevant past surgical history, she did have an ACL reconstruction with hamstring autograft two years prior and never really felt like her knee had gotten back to where it was pre-injury. And so about a year later, she had what she described as another meniscus surgery to address her meniscus and also another ligament surgery to stabilize the knee, although she wasn't exactly sure what had been done. In one examination in our clinic, notably she had a large effusion. She had rotatory instability as evidenced by a large pivot shift, and she had a 2A Lachman. So she had a good end point. I felt that her graft was intact, but she certainly had some increased translation, but otherwise was stable ligamentously with the rest of her exam and her vascular intact. This is a little bit of her imaging. We got an MRI, and you can't see the graft perfectly, but we felt like after looking at this that the graft was in place. You can see it on a few different slices here. And then I did get a CT scan ultimately with 3D reconstruction to look really at the tunnel placement. And you can see on the femoral side, you can see the femoral tunnel. And then on the picture on the right, you see what appears to be an interference screw over in the proximal tibia. And so a summary of the imaging from our standpoint was that the graft was intact. We did feel it was vertical. She had a lateral meniscus posterior root tear. Her graft inclination angle was 65 degrees, tibial slope, nine degrees. She had posterior condylar offset of 63%, and tibial tunnel diameter was 10 millimeters, as was the femoral tunnel. And she had evidence of a previous lateral extra-articular tenodesis-type procedure. And so we did decide, due to her symptoms, to proceed with a revision surgery, and really the decision was, which graft do we use? I think that there are a lot of considerations to think about when you're trying to decide which graft to use. You know, one of the first things is which graft was used in the primary surgery, because that may affect what we use secondarily. There's some descriptions of quad tendon autograft being utilized twice, but most of the time, whatever graft they had the first time, you're not going to be able to utilize that the second time around. I ask myself, is this something that I'm going to try to do in one stage, or am I going to stage this? Where are the original tunnels? Where's the tunnel size? Thinking about concomitant injuries or procedures that I may be doing, how many ligaments will I be addressing at one time? And then, just like a primary ACL reconstruction, you know, there are individual patient factors that we have to think about. How old is the patient? What do they do for a living? What kind of sports do they play? What are their functional demands? You know, is there a timeline for their return to play or return to work? If you're thinking about utilizing an allograft, are they available? Do we have those allografts at our facility? What's the comfort level of the patient with using donor tissue? And those are things that we oftentimes overlook, but something that we should think about. And also, just like, you know, primary ACL, what are the patient's kind of bony anatomy and other risk factors for recurrent instability? Our allograft choices for ACL reconstruction from a primary standpoint and revision setting are very similar. I think they all do a great job of recreating the native characteristics of the ACL. Hamstring, BTB, and quad tendon tend to be the big three allografts that we use. You can use a bone block with the BTB or the quad tendon, but in a revision setting, it's important to remember that you're limited to a bone block size. So, if you have a huge bone void to fill, you may not be able to do that with an allograft. From a quad tendon standpoint, you know, I think it's less commonly utilized as a primary ACL graft if you just look at the number. So oftentimes, it's available for you to use. On the allograft side, if I'm thinking about something longer, maybe an over-the-top technique on the femur, I'm leaning more towards a longer graft like an Achilles. For BTB and quad tendon, oftentimes, what we do in a primary setting for the surgical team can be translated very well to a revision setting, and that's what I like about using those allografts. You know, this data is a little bit old, but it just shows that in general, many primary ACLs, most primary ACLs are utilizing hamstring autograft just from a number standpoint, and so most of the time, I'm looking for a graft that's different than a hamstring when I'm in the revision setting. I do think that, you know, I agree that the quad tendon is probably the graft of the future, and I utilize it a lot for my primary ACLs. I think there's some great characteristics about it, and we're seeing it more and more, you know, and it's really my workhorse for autograft for revision ACL reconstruction. I like the fact that I can reliably know what size graft I'm going to be able to get. There's a lot of collagen in that graft. It can be done through a small incision, which sometimes isn't as important in a revision setting, but I think it's still important to many patients. We don't find that they have as much herbicide pain as they did with the BTB, and there's a lot of cross-sectional area compared to the patellar tendon, which is also utilized often. But, you know, my algorithm, I try not to treat every patient the same, and so we're really looking at the overall picture of the patient. I lean towards a quad autograft or a BTB autograft in my higher-demand patients. Certainly if it's a high-demand patient that maybe is a carpenter, a kneeler, or martial arts, I may lean more towards the quadriceps tendon autograft. If I'm going to do a single-stage procedure in a patient with anatomically-placed tunnels, I usually be in a situation where they don't have any widening and I don't have a big bone void to fill. If I have a big bone void to fill, oftentimes I'm thinking about more of an allograft setting. I'm also utilizing that maybe in a lower-demand or older patient. If the patient has had multiple revisions already and there just aren't as many autograft options left available, then the allograft is a good option. Or if we're addressing multiple ligaments at one time, sometimes I'll move to an allograft as well. So we'll just kind of go back to how this applies to the patient that we're talking about, 18-year-old high school basketball athlete with a couple of knee surgeries already. Our imaging shows that we have a graft that's intact, but somewhat vertical, and of course our CT scan. And so the medical decision-making for me really revolved around this specific patient. She's a high-demand athlete. She has plans to play and some offers to play at the collegiate level. She had a previous hamstring autograft, and so that's not really an option for me anymore. And then I really had to address and assess why was she having this persistent rotatory instability. And her specific situation, I thought that a lot of it was due to the femoral tunnel placement and the graft positioning and the fact that she had this resultant root tear along with it. She did have some anatomic risk factors for instability, but I really felt like graft position was playing a big role in her case. Her tibial tunnel was placed anatomically the first go-around, and there was not any significant widening, so I felt that I could reuse it. And the femoral tunnel was not placed in what I would consider anatomic position, so I didn't think it would really affect where I wanted to place my femoral tunnel, so we could do this in a single-stage procedure. And we're really looking at just reconstructing or addressing one ligament in this case. And so I did choose to go with a quad tendon autograft. Here's some intraoperative pictures. You can see her graft on the top left, which was going really into the roof of the notch. She had this kind of complex tearing of her lateral meniscus that did involve the root. So we harvested the quadriceps tendon endoscopically, a partial thickness graft. You can see in these pictures that we were able to place our femoral tunnel where we wanted to from an anatomic standpoint without really any getting in the way from the previous graft, which we had debrided, and then, of course, address the lateral meniscus as well. Okay, so thank you. Great. Thanks, Jeremy. Great talk on graft choices. We can maybe discuss later what everyone's preference is. So next up will be Lyle Cain. You can get your talk up. We'll talk a little bit about what else to do, ACL, and maybe some other stabilizing procedures. Lyle. Thanks, guys. So I'm going to talk about when I add a lateral procedure to revision ACL surgery. So initially, we'll talk about the anatomy of the interlateral knee. We'll talk a little bit about the biomechanics, specifically with the ALL. Then I'm going to tell you about my rationale and treatment algorithm, and when I add lateral procedure like an ALL to revision ACL surgery. So a little history. The ACL was first described back in the 13th century by Claudius Galen, but really the first good description was by Sagan, Sagan fracture. 1879, he described the symptoms and signs of an ACL rupture, which included a rapid joint effusion, abnormal translation, audible pop, and pain, but he also described this anterolateral tibial avulsion fracture, known as a Sagan fracture. This is what they look like. We've all seen them, and we now know that this really represents a distal ALL bony avulsion at the attachment of the ALL on the tibia between girder's tubercle and fibular head. So if you look even a little closer to our time, so 50 years ago, Jack Houston, kind of one of the founders of modern sports medicine, and the mentor of my mentor, Jim Andrews, believed that the ACL was not important. It was not the cause of instability and really didn't need to fix it, and that was not uncommon in the 70s and even probably in the early 80s for some people, and so the focus was on this rotatory instability, anteromedial or anterolateral rotatory instability, not on ACL reconstruction, and at that time, many lateral-based reconstruction techniques were developed to control this rotatory instability. I feel like now we're kind of in 2021, we're back at that same point where everybody's trying to find a good lateral-based reconstruction to help augment their ACL, and I'll show you why I think that's occurring. So the Andrews technique was kind of a modified IT band where they'd take the IT band and actually take it through the, let me find my laser pointer, take the IT band, they'd route it around the back of the lateral femoral condyle through the knee and then down through the tibia. That was the Andrews technique. Probably the most popular technique was the Lemaire or the modified Lemaire technique. Lemaire took the IT band, drilled two tunnels in the lateral femoral condyle, and passed it down through the tunnel and then back to itself at Gertie's tubercle. There's a modification where you can take it and just wrap it around the lateral gastroc, the fibroclaw ligament, and stay superficial, the popliteus tendon, and come back to itself. So these were attempts to try to stabilize the knee, and when you're doing this, it's important to think about the anatomy. The important parts that are pretty obvious for most people, the IT band and Gertie's tubercle are really important landmarks, and the LCL and fibular head are important landmarks, and this anterior lateral ligament complex, or this tight capsular structure, lies just between the two. So it lies right here from the lateral femoral condyle down to halfway between Gertie's tubercle and the fibular head. So the ALL was first described by Sagand, but it was kind of forgotten until about 2013 when Stephen Clase in the Journal of Anatomy put this paper together looking at the anatomy of the ALL of the knee, and he said it originates near the lateral condyle, runs along the lateral outer aspect of the knee, and inserts on the proximal tibia between Gertie's tubercle and the fibular head. Now according to Clase, if you look at MRIs and critique the MRI on ACL injuries, ALL and capsular injuries occur in close to 80% of all these injuries. So it's a very common injury structure with pivot-shift mechanism. Most of these are distal, about 20% are proximal, and only 2% have a true bony avulsion or a Sagan fracture. What about the biomechanics? Well, studies have shown that the ALL does restrain internal rotation of the tibia and can affect the pivot-shift phenomenon in the ACL-deficient knee. So it's important as a secondary stabilizer, and therefore it's been proposed that a deficient ALL or lateral capsule can be responsible and can be the reason for rotatory instability after ACL reconstruction. So when is the ALL most important? Well, from a board standpoint, if you're answering a board question, these are the kind of common ALL augmentation indications. Severe grade 3 pivot, severe instability, so someone like this that basically dislocates when you do a pivot-shift and you have to pop them back into place, or for high-level contactor cutting athletes, and some patients that have prior ligament dyslexia, those MBI patients that also have an ACL tear. But the controversy really is truly in the true indications. I know some people are doing these surgeries on every ACL, and some people are doing it very sporadically. The best graft choice and fixation has been discussed in several papers and several talks. Some people are using something like an internal brace alone, and the graft placement is pretty well standardized, but the femoral side is a little bit controversial. So I'm going to tell you about a new concept that I'm kind of partial to. I think that some of these low femoral tunnel ACL tunnel placements can cause laxity inflection and may require ALL augmentation for stability, and I think this is why some patients, like the one Jeremy just showed, that have an intact ACL that's a little bit vertical, or they have an intact ACL that's a little bit low, feel unstable. And that person had had some kind of lateral procedure done at the same time. And I think the transition to a low medial portal anatomic ACL has caused some renewed interest in lateral extraarticulars and ALL, primarily due to some cases of flexion instability and early graft failure. So when early graft failure occurs, we all start looking for different ways to stabilize the need to protect our ACL, and I think that's why the ALL has become more popular over the last seven or eight years. So just in review, the ACL is not isometric, it only has a few fibers that are nearly isometric, and those fibers are the anterior medial bundle, which is at the roof of the notch. So the traditional trans-tibial, non-anatomic ACL that nobody likes in the literature. And we did a study looking at this, it was published in Journal of Knee Surgery a few years ago, and this is just the cadaver dissection, looking at the anterior medial bundle is not marked, the posterior lateral bundle is marked in purple, and you see how much excursion the posterior lateral bundle has through flexion extension. Because it's close to the articular surface, and on the back or the bottom of the cam of the femur, it goes through a tremendous length change through range of motion. This is a still picture looking at a simulated low-thermal tunnel, at the low-anatomic footprint in extension, and then in flexion. And what happens, as you can see, is that if you tension the graft in extension, it's loose in flexion, and I think people that play certain sports like basketball and soccer, when they are constantly in a flex knee position, a defensive position, or cutting in soccer, I think sometimes they have some instability related to laxity of the graft that is more lax than their normal ACL would be. This is another schematic kind of video looking at this, watch how much, as you go into extension, watch how much this excursion is between the low-thermal tunnel and the tibial tunnel. And your graft has to make this move as you go through flexion extension. In contrast, the higher-thermal tunnel is more isometric, and so it only has a couple of millimeters of excursion through range of motion. It's not as anatomic, it doesn't have maybe the same rotational control in extension in some of the testing that people have done in the biomechanics lab, but it certainly has better isometry. So this low-thermal tunnel problem was kind of brought up in 2015 at a Herodicus meeting in Lyon, France. Mark Clatworthy from New Zealand presented his data where he had seven consecutive years of trans-tibial high-thermal tunnel, followed by seven consecutive years of low-medial portal tibial tunnel independent thermal tunnel. And what he showed was that he had a 350%, 3.5 times higher failure rate using the low-thermal tunnel compared to his high-tibial tunnel. Andy Pearl had a similar data with 7x times higher with BTP, because the BTP is a ribbon and doesn't fill as much footprint probably. So Russ Warren at this meeting in 2015 said, one of the biggest mistakes of my career is when I listened to you guys talking about a lot of the Herodicus members and started trying to get anatomic, and my failure rate went up, I abandoned it, went back to my old technique, and you have to realize we're not making a new cruciate. It's not the same biomechanically, it's not the same fiber makeup, but we're making a temporary strut to stabilize the knee. So why higher failure rate with medial portal with low-thermal tunnel? It has to do with this isometry. So this is our data from our paper we published. The higher-thermal tunnel on the left, as you go through range of motion, only has a couple millimeters of graft excursion or strain. The lower-thermal tunnel, because of that cam effect, has between 10 and 12 millimeters of excursion. So if you fix the knee inflection, they're going to be over-constrained and they won't get their extension. If you fix them in extension, they're going to be loose inflection. So it's kind of a catch-22 situation. So the quandary is when drilling trans-tibial, and you place the graft in a vertical non-anatomic location, you have failed rotational control and poor outcome kinematically. But also if you go too low, then you have an isometry of the graft and you can have a higher failure rate or loose knee inflection, which can be that person's important position depending on their sport. So how did this change my technique and what does this have to do with ALL? Well, I'm okay with slightly high-thermal tunnel, with the patella tendon graft especially because I can rotate the graft and put it where I want to. I want it to be right at the center of the footprint, not low. I'm much more selective about hamstring grafts and will go medial portal sometimes knowing that the graft has to fill the entire tunnel and I can't rotate the graft as well. It is where the hole is. I think this push to be more anatomic has led to better biomechanics in the lab at the expense of significantly higher early failure rates, mostly unreported and just recognized as bad luck that the patient came back too early. So we need to lengthen our rehab protocol and we need to change things by putting an ALL in because their knee is unstable and we need to constrain the knee more to prevent the ACL graft from failing. And I really believe that ALL augmentation has become popular because of some of these non-isometric graft placements. So what is my treatment algorithm? Well, when do I use an ALL? So extra loose knees, I call them. So knees that have a grade 3 pivot, I'll think about it. If they have a severe injury mechanism in a cutting athlete, I think about a lateral based augmentation because it does give them some rotational control. The MDI knee with traumatic ACL that's already hyperlaxed, those people are typically the grade 3 pivot shifts. But if they're just kind of that loose knee that flops all over the place, I think about doing a lateral based augmentation. In revision cases when the graft is intact sometimes or torn and has a positive pivot shift, I'll do an isolated ACL. So the case that Jeremy showed, I think that person already had some type of lateral procedure. But if you've got a graft that may not have great rotational stability, sometimes an isolated ALL will help control that rotation rather than having to redo the ACL. And that's true for vertical graft or for a low medial portal graft. Both can have problems depending on the biomechanics of where you put the graft. So my experience here at ASMI in Birmingham, I do about 150 primary ACLs a year and about 30 revisions. Myself, I do 5 to 7 ALL augmentations with ACL reconstructions each year. And I'll do 2 or 3 isolated ALL augmentations on unstable knees that have intact grafts. My technique, I do about 75%. I use just a piece of tape alone. If I'm doing it in association with somebody that just has laxity or if I really am concerned about their instability profile, I use a gracilis autograft. So in conclusion, hardware is always nice. I was able to be awarded my 6th Natty Ring this year with the Crimson Tide. So on the second hand, it's a lot of fun. So anterolateral structures, the ALL and capsule are both important for rotational stability. I think that was proven back in the 70s. With any new idea or technique, and that's true for ALL, critically evaluate the concept. Don't just follow the leader. In my hands, ALL reconstruction is only used for very specific instability patterns. I don't use it on every ACL or every revision ACL. And I believe that some people are using the ALL to overcome a poor ACL caused by low thermal tunnel, non-asymmetric graft, or potentially from too vertical an ACL in the vertical part of the notch. So as a fellow, I think the main important thing for you to do, especially late in the year this year, is to ask why. Ask why your staff member does a certain technique or adds a certain procedure more so than the technique itself and how they do it. The why is more important because that's what determines how you run your practice when you get out and you're on your own. Thank you very much. Great job, Lyle. Thank you very much for this insight. So I'm going to go next. I can, maybe, all right, great. You can see my screen? Yes, no? I hope you can see my screen. So my disclosures, not really relevant to this talk, a few slides real quick on preoperative planning. Obviously, history, physical, is half your bet, maybe 90%. We take x-rays on every case, we take a long cassette on every case of revision, as well as MRI and CT scan. I'm sure not everyone is used to taking CT scans, but I'll show you a couple of images. Obviously, you have a lot of hardware to worry about, preference is to leave it in place. The screw on the third picture there with all the lines on there is very hard to get out. So if possible, we leave it in place. The shape of the tunnel is important. You look about bone grafting, look at a huge tunnel like this, it's very likely that you have to bone graft this before you can proceed. Here's some very important numbers for you to look at, so Bernard and Hertel and Stoibly, so they have come up with these numbers. So look at this radiograph in the middle, see where the tunnel is located. How do you assess whether this is anatomic or not? So this is the tunnel. Here's the grid that Bernard and Hertel described, and at 25 and 25, going from P to A and from Blumensatz line to distally is where the anatomy is. So this tunnel is essentially anatomic. On the tibia, the line is at 43%. And so in this particular case, maybe a touch anterior, but in essence, anatomic. So this is just how to measure this. Another angle you can measure is the anatomic graft angle. So the picture on the right is a trans-tibial reconstruction that is non-anatomic, unless you wish to do non-anatomic surgery, this is not where it should go. CT scans, again, so you can see here the diameter and shape, usually 16 is the number that people start thinking about two stages. My preference is always to go single stage. So I ask you here, do you think this is anatomic tunnels? Really hard for you to say, therefore go 3D. Now, you know, this is very much unacceptable, an anterior tunnel, and they have a higher failure rate. MRI, as you can see, look about concomitant injuries. As mentioned before, some of the cases have some capsule injuries, certainly not 80%, but there is a number that you need to know and look about medial and lateral injuries. And here you have three, basically, algorithms. The tunnel is either anatomic, and you can simply revise it in the same, or they're semi-anatomic, which most of them are, and it's very tricky to revise, because you may not want to use the same tunnel if you think that that is the reason why it has failed. Or they're clearly non-anatomic, which again becomes very easy because you simply make a new tunnel, just like Jeremy has shown. Over the top is a technique that's underutilized. Lyle showed the Andrews technique, which is over the top. It's actually a very elegant technique we use in pediatrics a lot, and we use it also in the revision setting a lot when the tunnels are semi-anatomic. And we also use it, as Makachi and Zavanini described, to do a lateral augmentation, if you wish. So here, tunnel positions is really the most important factor for you to figure out where to go. So let me just show you a few cases here, just to show you. Let's see if I can get rid of this. So this is a primary ACL done with hamstring tendon. Essentially, the tunnels here are anatomic, so you would just go ahead and drill a new tunnel in the same tunnel, using a different graft, in this case, quadriceps tendon. So this is one case. Here's a different case, very interesting. So this is the one I showed earlier with huge cystic tunnel deformity. So you probably go ahead and bone graft these tunnels in just about anyone's hand, and it makes it likely a two-stage procedure. Now interestingly, in this particular case, it was bone grafted, packed up, and then really the patient's pain got so much better that they never really wished to undergo the eventual second-stage revision, because oftentimes this is a pain issue, which is very tricky to treat. Since you all know, ACL gives really more instability rather than pain, but the cystic tunnels can give you pain. So bone grafting, you can use dowels, autograft, allograft, iliac crest is probably the gold standard. You can also use an Achilles tendon allograft, and depending how large you make the calcaneus bone block, you can fill most of the defects, and you can also turn the Achilles around. So if the tunnel is a little bit too posterior, then you can simply turn around the graft, and so that helps. Here's another case. This is a double bundle procedure that has failed in a 17-year-old, a year and a half after. You can see here on the CT scan that especially that low tunnel, just like Lyle has shown earlier, the one that is so non-isometric is probably not the correct position. So here, we can revise it by using an over-the-top technique quite easily, and use the same TBL tunnel. So over-the-top, if you look at the middle picture, you wouldn't really know that this one never received a tunnel, but simply goes over-the-top because it looks so normal to your view. Here's a 33-year-old. He had a hamstring ACL reconstruction with cross prints. Whenever you read cross prints, you know it's trans-TBL and non-anatomic. So they had persistent rotatory instability. You can see here, a normal ACL should be about 45 degrees or so, and his is 80. So very vertical, therefore rotatory unstable. It's really, you know, could be medial, could be lateral, it's so, so wrong. So here, you can use a totally new femoral tunnel, there's plenty of room, and be done with it. Now, of course, once you do anatomic, the question is, should you add lateral, yes or no? Here is a 33-year-old. This is the post-op image, and you can see how the over-the-top looks quite nice. This is a 20-year-old football player. You can see slightly anterior tunnel placement there. This is BTB. So we did a quadriceps tendon for revision, drilled a new tunnel, and this is quite close to the previous tunnel. So you drill maybe a small diameter, and then dial it up, and you can sneak, quote-unquote, a new tunnel right behind it. So in summary you know have options available different grafts as Jeremy Burnham has shown different approaches outside in we didn't talk about it's a good approach to over the top is really something you should try to learn it's a nice little trick to have up your sleeves there's no such thing as a simple revision sometimes biologics can help to think about the pain case with the bone grafting and obviously be realistic with return to play. Lots of technical considerations so loose hardware needs to be removed otherwise leave it in place you can over ream biodegradable and plastic material screws and then there's always risk of tunnel collision again the 3d CT scan will help you and the outside in technique the slightly different angle. Consider the slope Armando Vidal will talk about this in a second. Consider coronal malalignment and meniscus roots ramp lesions the picture on the upper left there collateral and the interlateral of course as mentioned. So pre-op planning use 3d CT scans I prefer one stage revisions whenever possible bone grafting need to be available. Explain to the patients the complications beforehand so that they are well informed about all this and then explain to them whether you're planning on a two stage don't surprise them. Use intra-op fluoroscopy use quad tendon allografts can be versatile at the over-the-top. So thank you very much and now we'll go to Armando Vidal for the last presentation I think we're well on time and then we have some time to talk. Armando. Can you guys hear me? Yes. All right let me get my talk loaded up here and great talks guys just this is I think your last bullet point while I get this loaded up here that there's no simple revision is key I think you really need to be thoughtful about these revisions and have an approach. So part of this talk I just want to talk about slope I think it's a it's an emerging concept of a contributor to ACL failure and how do we manage it in some of these patients and I think we're still evolving our concepts on this. So you know why for all the fellows on you know why is this an important webinar it's because you guys are obviously all training to do a lot of ACL surgery you know ACL injury incidence is pretty high in this country there over 200,000 ACLs performed annually and coupled with this increase in the number and complexity so a couple of increase the number of ACLs being performs an increase in the number and complexity of revisions and there were 13,000 revisions performed annually in this country and the need for re-revision is somewhere between two and nine percent and as we just saw the revision rates can vary by age and graft and there's still emerging concepts on tunnel placement and their contribution to failure but in some demographics this is a graph from our moon group it can be as high as 25% and that's been shown across the world literature and that that curve is for allografts and young patients which obviously we've all learned is a bad choice but we know that our young athletes can have as high as five to ten percent failure rates and they're a highest risk group so in short if you do ACL surgery as you saw Lyle's practice makeup you're gonna be doing a lot of ACL revision as well because you're the specialist in here so you have to have a comprehensive way to approach these injuries and as you've seen a pretty deep skill set for how to manage tunnel widening, hardware, augmented you know extraticular augments, graft choices, etc. So we're gonna talk about slope but I think whenever you approach an ACL failure and I have a similar talk on cartilage injuries you have to have almost a checklist way to approach it and I think Volcker will appreciate this this was really Harner's way back when I was a Pittsburgh fellow gosh 17 years ago on how do you look at a revision and every time I see a revision I want my fellow to come out with a checklist of what they think the contributors were to that patient's failure. So we know technical is probably the most common and you've seen a lot of examples of poor tunnel placement in the previous talks. Biologic failures would be probably the second most common typically an allograft and a young high-level athlete. We know that missed associated injuries particularly the lateral side but I would argue that we're increasing our awareness of what comprises associated injuries that contribute to ACL failure including root tears and a meniscal deficiency. Malalignment and I think we're still unclear where coronal plane malalignment fits into the picture but certainly sagittal plane alignment i.e. increased slope we know is a contributor to ACL injury and ACL failure and I'll argue when you look at this x-ray in addition to looking at the slope and having a way to assess the slope you need to if you look at this this tibia it is anteriorly sublux relative to the femur and when you see this on a lateral radiograph that should immediately get your attention that this is probably a knee that's going to require something more than just a soft tissue operation. Lastly you have rehab failures and you have traumatic failures so I tell patients all the time if they can tear what God gave them they can certainly tear what I put in there we know that a diagnosis of exclusion will be a traumatic failure and then you have some patients that go back too soon or aren't adequately rehabbed or assessed for return to sport and again whenever I see a patient that comes in with an ACL failure I go through all six of these and I try to tease out which of these were contributors to their failure and what I'm and how I'm going to address those contributors to their failure in the revision. A lot of the previous talks have focused on technical aspects but I think the key to having success with any revision is knowing why they're there in the first place why are they in your office with a failed ACL and going through this checklist every single time you see them. So let's talk about slope so we know there have been several clinical papers that have correlated increased medial lateral tibial slope with ACL injury. Some people have argued that the risk of ACL re-injury Solomon published a paper showing an 11x higher risk of ACL graft failure in patients with slopes in excess of 12 degrees. We know they also result in an increased anterior tibial translation. There have been a handful of biomechanical studies that have looked at this as well this includes includes LeProd's work when he was here at Bale but also papers out of Europe showing that increased tibial slope has a linear increase on ACL graft forces and subsequently slope reduction decreases graft forces and subsequent anterior translation. Lastly there have been a handful of small papers looking at slope reduction and re-revision ACLs so ACLs that have undergone two or three failures showing excellent outcomes in the short term but again I would argue these are relatively small groups of patients. So similar to what what the previous speakers have shown I like to teach by example by showing cases so let's go show you a couple cases and how you can look at slope and how it can be valuable when you're looking at these revisions. So this is a 32 year old female she's had bilateral ACL tears in 2003. She both with hamstring grafts. She reached for the left in 2017 when a horse stepped on her. In 2018 she underwent a two-stage revision ACL by a very experienced surgeon. She had bone grafting first she then had a BTB autograft a fibular collateral ligament reconstruction and a lateral meniscus root repair and she comes in today with her primary complaint being instability a traumatic failure of her of her graft. On exam she has 0 to 140. No hyperextension is important because if you endeavor on correcting slope by definition you're going to increase extension because if you think about it you're going to essentially be extending the tibial shaft relative to the tibial slope or to the knee surface. In her particular case she had three degrees of hyperextension on the contralateral side so effectively an asymmetric flexion contracture despite having zero degrees of extension. She had no effusion a pretty typical ACL exam 2 plus lockman 2 plus pivot and she'd had previous lateral sided surgery and that was stable. So similar to what Volker was saying every patient in our practice with a revision ACL gets a long alignment film. You can see from a coronal plane she is stable. She has a lot of hardware in position. I would argue that I think her tunnels are in pretty reasonable position and this is that lateral I just showed. If you look at that lateral you can see that that tibia is I wouldn't say it's statically subluxed. It actually was not statically subluxed but it is subluxed relative to the femur on that lateral radiograph. There are a variety of ways to measure slope. I think the gold standard is still a full-length lateral radiograph of the tibia. I'm pretty liberal with the use of CT scan. I actually feel that CT scan is more accurate and additionally can help me with some 3D planning for some more modern osteotomy techniques. But she's got a 15 degree slope and an anteriorly subluxed tibia on her lateral radiograph. So this is in my hands going to be an osteotomy in the re-revision case or second time revision surgery. So I did stress her. I have a low threshold to stress to perform stress radiographs on patients that come in. Again going through that checklist of concomitant contributors to ACL failure. She's already had a lateral sided reconstruction and you can see here I didn't measure it on these radiographs but she is stable or at least symmetric with her contralateral side. And this is her MRI very briefly. You can see the tibia statically subluxed. If you if you tell a lot of these patients their tibial tunnel looks really anterior. Sorry it's going so quickly. But the tibia looks the tibial tunnel looks anteriorly subluxed but I would argue that relative to the tibial surface it's not as far forward as you think. A lot of it has to do with that tibial translation anteriorly. But this is going to get bone grafted and shifted posteriorly subsequently with her revision in my hands. So this is her arthroscopy just in the interest of time. She's essentially got an atraumatic complete failure to ACL. You have the PCL on the left there. I don't know if you guys can see my cursor. She did have a lateral meniscus root tear that had partially healed but you do see some loose suture material there. And I would argue that this is a pretty anterior. You saw all those pictures. You saw the grid that Volker just presented. I think everybody would argue that this is a view from the medial portal across the lateral formal condyle. That femoral tunnel is too anterior. So that's going to need to be revised as well. So looking at this particular case and that Venn diagram that checklist that I talked about I'd argue she has a technical failure. You could argue that that the her meniscal deficiency on the medial side can be a contributor to failure in this particular setting. And she clearly has malalignment in the sagittal plane. So this is a patient in my hands that's going to get a slope correcting osteotomy. And we'll talk about two different ways to do this. So her coronal plane if you recall was was normal. So this in my hands is a pure closing wedge anterior closing osteotomy, slope correcting osteotomy. Sonnery-Quetet has described this. It's been described by others. Historically it's been described with a takedown of the tibial tubercle, a closing wedge, and then repair of the tibial tubercle. However this can be done with a tubercle preservation. In fact it can help you if they have a little bit of Baja. So you cut behind the tubercle and then you make cuts convergent cuts using pins that you'll see on the lateral radiograph here to close it down. So this is what it looks like radiographically. You're gonna similar to your closing wedge or even opening wedge osteotomies you're gonna stop about a centimeter shy of the opposing cortex. So you can see it here. We're gonna use that as our guide for our saw. This always gives people pause because you're cutting back toward the vessels. But if you have convergent pins like this it could be done very safely and those pins protect you. It's hard to pre-shape it on that right side of view. The tubercle has been preserved so we do not have to take it down. And then you can actually manually close this down. This can be closed to staples. I've done that. This she had pretty soft bone proximally so I didn't feel comfortable with that. So we actually fixed it with a tomofix on the medial side and then a staple on the lateral side. And you can see here her pre and post-operative x-rays with correction essentially to zero degrees of slope and for thankfully for her restoration of her physiologic extension. Ultimately this is done a year ago. She's now a year out from the osteotomy. Now this was her. It's amazing how well tolerated this procedure is. This is her six weeks post-op from the osteotomy. Really remarkable range of motion. And then six months later we took out her hardware and revised her with a quadriceps tendon autograft and and fixed that root. I did not actually transplant her meniscus. She chose not to do that but you could argue that that would have been a reasonable contributor. This is a primary. So you may ask when do you use in the primary? The answer is pretty rare but I'm going to show you an example of how sometimes you have to correct these things in two planes. So this is a 20 year old male. Came in with left knee pain and instability. Tore his ACL three years ago and was misdiagnosed. So he had three years of playing basketball with instability and pain. Medial sided pain. No previous treatment. Clinically he's in varus. Motion is good. 0 to 145. He's tender along the medial side. Again a pretty typical ACL exam. 2B Lachman and 2 plus pivot. If you look at these radiographs it's his left knee. You see squaring of that condyle. Some early joint space narrowing. His coronal plane is mildly varus. About five degrees mechanical axis. If you measure this by percentage across the weight bearing surface he's at 28 percent and he's got a slope of 12.5 degrees and I'll show you how I made that assessment. But these are his this is his MRI and you'll see why an osteotomy would be powerful in this context. So his lateral side looks good. ACL is chronically torn. PCL is intact. And then we get to the medial side. Pretty rare in this context but he's got a complete root tear and he's got this large full thickness condyle defect. Again 20 year old male athlete. This is his coronal view. So this is a challenging case. So this is a patient where if I saw a 12.5 degree slope with a just an isolated ACL I probably would not consider an osteotomy. But this is a patient that I would argue with five degrees of varus, a chronic medial root tear, full thickness condyle defect. I'm gonna try to do everything I can to hedge my bets to get that medial side to heal. So I have a very low threshold to consider coronal plane correction in this context. And if I'm gonna be correcting the coronal plane I may as well take advantage of the fact that I'm there and optimize that slope in this context. So this is his scope video. This is where you get a nexus actually of the cartilage algorithm and the revision ACL algorithm. This is a pretty dramatic lesion for a kid this age. This is his root tear, completely evulsed, a couple fibers left there. So this is my, the Venn diagrams I think for cartilage lesions are smaller but it's instability, meniscal insufficiency, and malalignment. And I would argue if you view this guy as a cartilage case and not an ACL case he really has the nexus of all three of these things. So you need to restore meniscal function. I would argue with five degrees of varus in this particular context that should be corrected. And obviously you have to address his stability. So in summary he's an ACL deficient knee, valgus alignment, elevated slope, with a root tear and extrusion, and a large full thickness chondral defect. So this is what I did. So I did an ACL, anatomic ACL placement. We fixed his root. I actually chose a hamstring. In this case it's actually my least favorite of the autograft options but I was going to be exposing his entire intramedial tibia to do his osteotomy. So I took advantage of that exposure and the fact that I would never get a chance to harvest those hamstrings again. Thankfully he had a pretty big hamstring. We did an osteochondralograft to that extensive lesion on the medial formal condyle, fixed the root, and then did a small plane or sorry a biplane correction. And I did this all in a single stage. This is a unique hardware. Actually Volker and I were talking about this briefly before we got online with everybody. But this is a company that will 3D print the tibia and it can allow you to correct in two planes and work around an ACL tunnel. So in this particular case and actually a root tunnel. So we fixed his root and did his ACL. Not a great picture but we had a complete arthrotomy so it's hard to maintain fluid here. And this is his final correction with both slope correction, ocealograft, ACL, and root repair. What's nice about some of these more modern systems is that our biggest challenge with biplanar correction as you guys know is our ability to maintain the slope. The tendency with an opening wedge medial tibial osteotomy is that we increase the slope. We just did a study here where you look at all the things you can do to optimize it when you're doing a freehand technique which includes an asymmetric opening, meaning a wider opening posterior to open, sorry posterior to anterior, hyperextension maneuver, maintenance of a intact or front-to-back hinge on the lateral side, and in the best case scenario we maintain the slope or can maybe improve it by a degree. So for years I would try to do an opening wedge and try to hyperextend it and create a bigger wedge in the back than the front and what we really were doing is probably just maintaining slope. But our ability with an opening wedge osteotomy to truly decrease slope is challenging but I would argue with some of these more modern systems we're able to to improve it. And the benefit of this too, if you see in the picture to the left, I can move our screws around to create space for a tunnel. This is how it's pre-operatively templated. If you look here at the bottom line the tibial slope is 12.4 degrees preoperatively measured on the CT and we can decrease it to 7 degrees or whatever we needed to in this particular case so it can be pretty powerful. So in summary, posterior tibial slope correction it can be challenging and that can be done either with an anterior closing wedge osteotomy or biplanar osteotomy. I consider it in multiply failed ACL reconstructions where the slope is elevated greater than 12 degrees. It's rare for me to consider it in the primary setting but I'll consider it where the slope is elevated and the coronal plane needs to be addressed and if I need to address the coronal plane and I have a borderline slope in this context I'm going to correct the slope as well. So that's my summary but this is obviously challenging procedures and typically not even for a first time ACL failure is typically for the multiply failed ACL reconstruction. Thanks. That's great work Armando. So thanks to all three of you. This is this is really what I wanted to get out of this little symposium. I mean if you think about it we talked about grafts, interlateral osteotomies and tunnels. What else do you want to know? So I think this is super. Thank you all so much for these great talks. There are a few questions I already fielded and written down answers so keep them coming guys. I look at the image here on the right and keep answering them. Can I ask the panel, I'm going to give you this case scenario. So you're dealing with a failed BTB ACL reconstruction. Just the tunnel is fine. I want to hear your graft of choice and this is a in Armando in your case he's a skier. What graft do you use? Tell us just a little bit what you're thinking here and they're you know 21 years old. I would say if they're if they're high-demand I still like BTB as my option. So if I can go to the BTB so you go contralateral? I would that probably my primary choice if they're really high-demand. I think my secondary consideration would be quad from the ipsilateral knee if they didn't want to go and lastly would be hamstring but a 21 year old I would avoid allograft at all costs. Okay so you contralateral I think is a great option. I've done it rarely but I've seen a patient back today where I've done it and she loves it. Lyle for you of course it's American football player. What graft do you go to next? So it depends on the size of the patient. For an offensive lineman or a big guy I go contralateral patella tendon autograft. If it's a smaller person that has you know big big legs I'll do use hamstring quadruple allograft autograft hamstrings because you can usually get a nine millimeter minimum sometimes ten millimeter tripled graft. So soft tissue wise I use that over the quad tendon. Okay so you guys really like your patella tendons. Jeremy I know what you're going to use but tell us real quick have you done a contralateral BTB or always quad? Yeah I would go with a quadriceps tendon autograft in this case but we'll consider contralateral BTB as well. I'm gonna top it even if the guy has a huge patella I'm gonna do quadriceps tendon bone even though you already took the bone distally if the patella is big and you can see it on the CT scan. Okay next round of questions I start with you Armando again. Give me a number your primary ACLs you know in the 21 year old you know high level athlete let's talk top level athlete primary ACL how many percent get an interlateral procedure in and what kind and in the revision ACL say where you know you don't have all the other you know biologic and other failures give us your numbers. If I had to guess it's probably about I have similar indications to Lyle so it's probably about I'd say 10% maybe less than that maybe single-digit percentages it's usually in the primary setting specifically patients with hyper extension greater than 10 degrees high-grade pivot shift but we just did a kid who's a all-mountain skier that he talks off cliffs and stuff and we did a BTB but he's got 10 degrees of extension on both sides and he's a massive kid huge legs so we did a Lemaire in him so I'm so I like the IT band autographed I think the biomechanics are favorable I think the graft orientation is favorable it's it's an autographed and it's it's very easy to perform and it's time-tested so I'm a Lemaire guy when I modified Lemaire when I do it an ALL augmentation for my revisions it's probably closer to 50% maybe even higher so I have a very low threshold and I think the argument may be like some of these borderline slopes and we're studying this right now in our lab is is there a benefit to maybe adding an ALL in that context short of going to an osteotomy which there's carries a high risk of morbidity so so much higher my revision slope is high do you add an ALL or do you do both the slope osteotomy and an ALL I will try to I try to cheat and do an ALL if I can if they're multiply revised and have had like this patient I showed you is a fibular collateral ligament reconstruction has had a revision that staged and I'm I'm going to go all in but if I've got a borderline slope I will cheat with an ALL or with a Lemaire I should say percent in your case in the primaries and in the revisions yeah so I'll show the slide it'd be less than 5% so it's out of 150 ACLs I'll probably do five or seven primary ALL or lateral based procedures in the revisions a little bit more but probably still less than 10% I think in most cases unless they have a really lax aggressive pivot shift a grade 3 pivot shift I don't do the ALL or lateral procedure okay from your talk I was thinking you would more go towards 80% but you're really doing very few huh but you believe in the concept though yeah I believe in the concept I think the key to not needing the ALL is having having a graph that's more close to isometric yeah Jeremy yeah for primaries probably 5% or less and I think for revisions I'm probably around the 15 or 20 percent mark and you know modified Lemaire is what I would normally go with and just kind of looking at the overall picture if there's some bony morphology that I think it's high risk that I can't address surgically I'm thinking about maybe going on the lateral side or you know hyper laxity some of the other things have been talked about as well okay yeah and I told my fellow today we do the lateral procedure whenever there's a new fellow on the rotation because they haven't seen it so not not very much you're still trying to define really when when they're needed you know I agree with Lyle that they're in few cases in my hands needed right now but I do want to point out to everyone on the line you know stability one from our get good has shown that if you use hamstring tendons you know your failure rate goes from 10 to 4% if you add the natural procedure so that's certainly powerful data we are repeating the study right now with BTB and quad tendons Amanda you told us about your slope so it sounds like you're quite aggressive with this adding the slope procedure do you go trans-tubicle you go proximal to the tubercle ever or you go even below the tubercle I actually go at the level of the tubercle so it's what I do is I do a vertical cut behind the tubercle almost like if you were doing a PTO just to the proximal extent it's only you're only taking about a centimeter of bone sometimes less so that so I do a cut behind the tubercle that's the plane of my osteotomy I take out the wedge of bone from the medial side and the lateral side and then the tubercle slides up with the with the disc with a shaft essentially as you close that down and that prevents you from having to take the tubercle down now if you had to alter it I always look at their CD ratio pre-op and estimate what that's going to do to patella height post-op so I would have zero concern about doing taking the tubercle down and repositioning it if I thought I was going to negatively affect the teleformal mechanics lie are you adding osteotomies slope changing osteotomies when the corona alignment is neutral no generally the time I'm using osteotomies is if they have concurrent media from Wakanda aware like I'm like Armando mentioned in his talk I need to correct sagittal alignment alone I have not been doing the osteotomies so if I have somebody has a bad middle compartment revision ACL and they've got it they've got a various knee I'll do an osteotomy correct slope and crow alignment at the same time then do the revision ACL okay got it and Jeremy have you done have you touched the slope that way and if so is your goal to go to seven degrees or over correcting like dr. Vidal has shown yeah I'm not doing a lot of sagittal plane osteotomy is more in the setting of coronal plane or concomitant cartilage injury as well okay now I can tell you I've done a few in these last couple of months it's becoming more and more something to look at we'll probably assess it on every case we don't necessarily address it every case what I struggle with this Amanda the people that have 10 degrees hyper extension you know are you still daring to do it no I think that that's always part of my assessment preoperatively and those those are the challenging ones Volcker I think that's a great observation and every every time that the idea of a slope correction pops into my head I'm the first question I have I force myself is what's their hyper extension because you're right if they have 10 degrees of hyper extension and you change their slope you're gonna give them 12 or 13 degrees of hyper extension and they're gonna be pretty unhappy so I think those is where I would do everything I would probably I choose an autograph that I do an internal brace I do an lateral augment and I would throw the kitchen sink at it but I probably wouldn't touch the slope in that context okay got it and then maybe a final question on your tunnel management you're a femoral semi-anatomic tunnel non dilated you know 10 10 millimeters it's just not quite in the spot that you want do you go one stage two stage do you go over the top or do you just say I screw it I took take the 10 same tunnel I I don't care Amanda quick answer I you could do it all the above I I personally have a philosophy you never compromise in the revision there's a reason they're saying you for the revision so like so that's got to be your guiding light every time and however you get there is how you get there and I don't think there's a right or wrong answer I've got a low threshold to stage patients don't like it I've done two stages in one stage where I put a dowel in and then drilled right next to it and then then so that's a good technique that works you can use stack screws in that content you really want to avoid it so yeah I don't do two stage you know generally generally when I see a dilated tunnel or a large tunnels because it was a previous soft tissue graft and so when you have a previous soft tissue graft you always have patella tendon as an option so I'll leave my patella tendon tibial bone plug large and use that to do a single stage bone graft at the time of revision by packing it with that enlarged bone plug got it Jeremy yeah I don't hesitate to stage if I need a graft I'll do that and do a two-stage revision but try to get it right where I think it needs to be okay I myself will go over the top quite frequently and I use an allograft of course in a young patient I don't like using allograft but over the top is what I do so at this point be out of time I would say this was a great discussion I was I hope that I feel that the questions okay in the text box so hey just to summarize you see we've talked about all the big topics we utilize osteotomies we utilize the lateral procedure we worry about the tunnels and make sure they go in the right spot and we use autograft whenever possible BTB seems to be the top choice followed by quadriceps it's really a 50-50 on our panel but I chose the panel so no conflicts so hey thanks so much Armando Lyle Jeremy thanks for 80 some people to tune in we appreciate it and we see you all in Nashville thanks Meredith to for organizing this thank you thanks I would like to remind the current sports medicine fellows about candidate membership if you have not already you may apply online for free candidate membership by clicking on the membership tab at sports med or open for free registration for current fellows is the pediatric sports medicine webinar series in collaboration with plasma there are two more sessions taking place tomorrow April 14th and on April 21st you may follow the registration directions listed here register today for the AOSSM ANA combined annual meeting taking place on July 7th through 11th in Nashville and for more online and on-demand education and resources visit the online AOSSM playbook and surgical video library at sports med org playbook page thank you again doctors Burnham Cain we saw and Vidal for your time in preparation for this webinar and we will see you next month on May 11th thank you for participating good night thank you see you

revision ACL surgeries

graft choice

osteotomies

tunnel management

slope correction

comprehensive approach

individualized approach

patient demographics

associated injuries

graft options