Good evening everyone and welcome to this AOSSM webinar titled The Other Ligaments of the Knee, a focused discussion on evaluation and treatment of knee ligament injuries. Thank you for joining us. Here are the disclosures of the faculty and organizers for tonight's webinar and the learning objectives. CME credit is available for this activity. You'll receive further details at the end of the program. I am now pleased to introduce tonight's moderator, Dr. Justin Ernat. Dr. Ernat is a board-certified orthopedic surgeon in Salt Lake City, Utah. He serves as the head team physician for the University of Utah men's basketball team and is a team physician for the U.S. Ski and Snowboard Association and the Utah Jazz. He has published numerous orthopedic research papers and has presented his research at national and international meetings. With that, I'll now pass the program over to Dr. Ernat. Thank you, Ashley. We're all excited to be here tonight to discuss the non-ACL ligaments of the knee. We figured the ACL gets enough credit. We forget about these other ligaments. We needed to educate each other and all of you on these non-ACL injuries and how are we managing them, what's the most up-to-date literature, and approaches and controversies for that matter. I'm excited to be joined by Matt Matava. Matt's from the Washington University in St. Louis, Missouri. Also by Dave Bernholt, who is at the Campbell Clinic in Colerville, Tennessee. And lastly, by Armando Vidal, who's at the Steadman Clinic in Vail, Colorado. So, we have an excellent panel, sure to learn a lot tonight. And again, we're just glad to have you. So, with that being said, I'm going to turn it over to Matt, who is going to educate us on his approach to PCL injuries in the knee. Thank you, Justin. All right, well, thank you for the introduction. Sorry for the brief technical delay. So, my topic is going to be PCL injuries of a 2024 update. These are my disclosures. Nothing is particularly relevant for this particular talk. So, before we talk about PCL reconstruction, how to treat it, I'd like to actually talk about the anatomy. As you remember from basic science, the anterior lateral bundle and the posterior medial bundle comprise the PCL. In terms of the anterior lateral bundle, the AL bundle, we'll call it, its femoral insertion is about two times larger than its tibial, which is very relevant for any sort of reconstructive procedure that we are considering doing for the PCL. Its tibial insertion is more proximal, hence the anterior and the lateral, the word anterior is for the femoral side, the lateral is for the tibial side. Its tight inflection, its strength is actually significantly more than the posterior medial. It's 1,620 newtons. The posterior medial bundle has a very elongated femoral insertion, as you can see on the diagram on the right. Its tibial insertion is more distal. There's about a nine millimeter separation on the tibial side between the ALB and the PMB. It's very tight in extension. Its strength is only about 258. So, that's why, for the most part, the reconstructive procedures done previously have sought to reconstruct the anterior lateral bundle if you're going to do one kind of bundle reconstruction. Now, the anterior lateral bundle is considered to be on the roof of the intercontinental notch. It's about one and a half millimeters from the articular margin, whereas the posterior medial bundle is on the wall about almost six millimeters from the edge of the articular cartilage. And if you're going to consider doing a double bundle reconstruction, which we'll talk about, these two bundle centers are about 12 millimeters apart. And obviously, you need at least a centimeter apart so you don't have any convergence of your bundles, and we'll talk about that briefly in the surgical section. Now, the meniscal femoral ligaments, which you're all familiar with, comprise about 20 percent of the PCL cross-sectional area. The anterior humphrey and the posterior risberg are about three millimeters by 21 to 28 millimeters in length and distance. The prevalence of both are actually less than 20 percent of all knees. You'll see one or the other in about 70 percent of knees. And really, the cause of these variability is unclear. Some researchers think it's an age-associated degeneration. Others consider there may be trauma. Either way, you only see them both in about 70 percent of knees. And the role of the meniscal femoral ligaments, at least the one that's suspected, is to hold the lateral meniscus medially as well as anteriorly with knee flexion. Now, in terms of biomechanical comparison of the two bundles, by far and away, the anterior lateral bundle is two to three times stronger with increased ultimate load and stiffness compared to the posterior medial bundle, as you saw in these two slides from Chris Harner in Pittsburgh. The anterior lateral bundle is predominantly tight in flexion. The posterior medial bundle predominantly tight in extension. And the PCL, as you all know, is the primary restraint to posterior tibial translation. You can see here on these three, on this bar graph, the PMB bundle section is the yellow. The anterior lateral bundle section is green. And if you complete a section of both bundles, you have significant increase in posterior tibial translation going from zero to 120 degrees of knee flexion. So by far and away, more is important in posterior translation. Now, the common mechanism of injury, keep in mind, compared to ACLs, a PCL injury is an injury of disability, not instability. The most common cause of injury of the PCL is hyperflexion. Typically, this involves a fall in the flex knee with the foot plantar flexed. With the foot dorsiflexed, oftentimes, we'll see a fracture of the patella or proximal tibia. Occasionally, you'll have a PCL tear with hyperextension beyond 30 degrees. You may have a varus or vagus load with rotation. And this typically results in a multiligament reconstruction, injury, rather. So PCL tears, this is a diagnosis that's often missed. There are 10 times less common than ACL tears statistically. And so those who do not evaluate injuries very often of this nature, they're not going to be used to seeing a PCL. They're not going to be thinking of a PCL. They tend to have fewer signs and symptoms. There's less infusion. Again, there's no feelings of instability like you will with an ACL tear. The associated injuries often get more attention than the PCL in a multiligamentous knee. Oftentimes, you don't do a careful exam. You'll miss it. This is very common in an emergency room setting. Also, you see the effect of gravity that can influence the diagnosis. So again, not to get too poetic, but as Henry David Thoreau said, it's not what you look at that matters, it's what you see. And oftentimes, I think that describes how we actually diagnose PCL tears. Now, we're all familiar with the isolated posterior laxity test. You know, if you run your thumb down the femoral condyle and the tibial plateau with the knee flex 90 degrees, the tibial plateau should stick forward about a centimeter. If not, with gravity, that can indicate a subtle PCL injury compared to the contralateral knee. You may have a SAG sign. You can have a quadriceps active test with active knee extension. You'll have anterior tibial translation of the tibia. And then with gravity, you can see on the lower left hand and then with the posterior drawer, which is the most common test, you'll often indicate increased laxity. Now, there's three grades of injury, grade one, two, and three. As I mentioned earlier, the tibia should be about a centimeter anterior to the femoral condyle at 90 degrees. If it's less than that compared to the contralateral side, that's considered a grade one injury. A grade two injury would be if the tibia is flush with the condyle. Grade three would be the tibia actually posterior to the femur with posterior translation. Now, you may have a lesser, if you have lesser grades of injury, like a grade one or two, internal tibial rotation may diminish the posterior drawer that you see. And so something to keep in mind when you're evaluating these patients who don't have a significant injury is try with internal tibial rotation, see if that actually diminishes the amount of translation you get. Now, there's operational grades of injuries, as I put here, from zero to seven millimeters, that's considered a partial tear. And that's side to side differences compared to the contralateral knee. Eight to 11 millimeters is considered a complete tear. And if you have greater than 12 millimeters compared to the contralateral side, you really have to think about a combined injury, either the posterior coronary or the posterior medial side of the knee, as some of our other speakers will discuss. And in terms of the clinical evaluation in the literature, it has a sensitivity of 96%, a specificity of 97. So again, if you have a significant injury, you will typically be able to diagnose this on your physical examination. Now, in terms of radiographic findings, most acute PCL tears do not have any radiographic findings. You may see a tibial avulsion in children. You can see an arcuate sign, which is a fibular head avulsion, which is seen in multiligamentous injuries. If you have a chronic injury, you may see a sag on the lateral view. For the most part, most of these injuries do not have any relevant plane radiographic findings. Now, with chronic injuries, you may have medial joint space loss because of what happens with chronic PCL tears. You will get increased degenerative changes in the medial, as well as the patellofemoral compartment. You may have patellofemoral degeneration on MRI or even plane X-rays. And again, for the long-standing injuries, you may see various malalignment compared to the contralateral side, which you'll pick up only on a long cassette X-ray, as is shown on the right here. Now, PCL stress radiography, I think, should be an integral component of any person's clinical setting. If you see a lot of knee injuries in athletes, these are considered to be more accurate than the physical examination or the KT-1000, which is used typically for ACL tears, in determining subtle side-to-side or objective measures of difference in posterior translation. You can use a variety of ways. The TLS device, as you show on the upper left-hand figure there, hanging weights, we typically do, or even body weight. It's a very accurate objective exam. Typically, if you're going to report anything in the literature, you need to have some sort of objective measurement to report. This will be very effective in telling partial versus complete tears, as well as acute versus chronic tears. And so this is, on the left-hand figure here, this is a device that we actually, one of our radiologists had her husband as a carpenter make it. It's a very simple device to use a patient's body weight. And what you're trying to do is cause the posterior tibia to translate posterior, I mean, the tibia to translate posteriorly in relation to the femur. And there's a couple of methods of doing this. There's a Jackman method, and there's a Stobley method, which is shown here. And basically, you're drawing a line on that 90-degree view of the knee with weight bearing between the posterior aspect of the femoral condyle and the posterior aspect of the tibial plateau. And you compare the two sides, and that's the side-to-side difference to use. And again, it's a very objective measure in trying to diagnose these injuries. Now, MRI, obviously, everybody who has a PCL injury is going to most likely come with an MRI. The bottom line here is there's a lot of literature that showed, in some studies, up to 100% sensitivity and specificity. It may not be that in all studies, but certainly, it is a very accurate examination method. In my experience, there's been no real correlation between MRI and degree of laxity. I've seen a lot of MRIs and PCLs that look very bad in terms of what you think might be the amount of laxity they'll have. In reality, they may have a grade one injury. And in distinction, you may have one that has a very good-looking MRI, but then have grade two to three laxity. So the MRI, it's going to tell you that there's an injury. It's not really going to tell you how lax the patient is. It's really less reliable for partial tears or for acute tears. And 30% of these injuries may actually show reconstitution over time. Keep in mind, again, this is a intra-articular, intra-snovial structure. So there is some feeling that PCLs can heal to a certain degree over time. But again, I do want to emphasize that the MRI is less reliable than stress x-rays in order to determine the amount of laxity present. Now, if you look at the natural history of PCL tears, again, this is an injury of disability, not instability. I put this on here, on this slide twice, just to emphasize that point. Isolated tears in athletes tend to lead to satisfactory function in the short term. The degree of objective laxity really has not correlated very well with the severity of symptoms. Patients will often develop functional adaptation, typically through quadriceps strengthening. However, there is an increased risk of OA, meniscal injury, and chondro injuries long-term with these injuries. A couple of studies that I've showed, that I've quoted here in the lower right, showed a five-year risk for OA, 80% of the myoformicondyle, almost 50% of the patellofemoral joint. At 12 years, there's a three times higher risk of knee and total knee arthroplasty with a patient with a PCL injury than those who have not had one. So again, obviously, over time, chondro degeneration is to be expected to a certain degree. Now, in terms of non-operative treatment of PCL tears, the indications in my mind are a posterior drawer less than eight millimeters, a partial tear by MRI, less than three millimeter displaceability of bulging. Any patient with open physis, no rotatory laxity greater than 10 degrees, no symptom of varicobagas laxity, and as well as quadriceps dominant activities, these patients can typically be handled non-operatively. Now, I would say consider surgery for a partial tear if the patient's symptomatic with deceleration, or were they ascending and descending and inclined. Some patients who have a more of a hamstring dominant activity, like for example, a cornerback in football, they may have issues with lesser degrees of injuries, but for the most part, the indications I have here on this slide, I think will at least have served me well for 30 years in terms of treating these patients successfully non-operatively. Now, you occasionally will see an avulsion, as I mentioned earlier. A lot of times this is in younger patients. In terms of fixation options, you can do either open or arthroscopically. Open repair, typically for displacement greater than three millimeters, the fragment obviously has to be able to hold a screw or some degree of fixation. They should have greater than or equal to grade two laxity, and the patient should be skeletally mature just because of the nature of the fixation you're going to have to use. In terms of an arthroscopic repair of the avulsion, typically this is best done in acute injury less than three weeks. If it's older than that, it's already starting to heal, and you're probably not going to be able to mobilize it very well arthroscopically. The best situation is if you have a hinged bony fragment that's displaced greater than three millimeters, again, in a less than three-week period of time, and really the patient should not have any significant tibial plateau fracture that may compromise your fixation. These are not very common injuries, but again, if you do see them, and they do kind of meet these criteria, they can be treated successfully arthroscopically. Here's an example here in the lower right showing an arthroscopic fixation of a PCL avulsion. Now, PCL reconstruction is sort of the workhorse of how we fix these, and this is certainly adopted rather than changed and evolved over the past 10 to 20 years. You know, what's accepted no matter what you do and whatever you talk about, you want a strong graft, you want anatomic tunnel placement, you want secure fixation, you obviously want to address any associated deficiencies and minimize any neurovascular risks that's sort of unique to the PCL. Now, what is debated is the number of graft bundles, either a single bundle or double bundle, how you fix a tibia, either through an inlay approach or through a trans-tibial, and then whether or not using any sort of internal bracing or other sort of artificial component to your graft. And so, if you look at, start with the double bundle concept, and I've evolved to a double bundle reconstruction using an inlay in my patient population, I've been happy with that. The rationale to reproduce the anterior lateral NPM bundles, both. The single bundle has been shown to be prone to failure over time. It causes uneven load distribution through a full range of motion. You may have good stability at, you know, 80 to 90 degrees of flexion, but you don't have a good stability in less than 30 degrees. Selective bundle tensioning, as I said earlier, the anterior lateral bundle is tighter in flexion, the posterior medial bundle is tighter in extension. And so, as you can see on that slide, that figure on the right, as you go through a full range of motion, you'll have sequential tension or differential tension of those two bundles. You don't get that with a single bundle reconstruction. And there is biomechanical support, very good studies shown in support of the double bundle concept. And so, here's a study here that was done by Okonobitics that showed if you have applied posterior tibial load from 0 to 120 degrees, again, if you section the entire PCL, that's the dark blue bars, if you just do the single bundle reconstruction, that's the green, you can see there is significant improvement in terms of posterior translation. But it's not until you do both bundles, you have significantly reduced amount of posterior translation throughout the entire range of motion from 0 to 120 degrees. So, again, the biomechanical support is there if you want to migrate to this. In terms of femoral tunnel placement from an anatomic standpoint, we talked about the anterior lateral bundle being more on the roof and the posterior medial bundle being more on the wall, just off the articular edge. Again, you want to leave a significant bony bridge if you can. Bundle fixation, if you're going to do the anterior lateral bundle, about 80 to 90 degrees knee flexion, the posterior medial bundle at 0 degrees. Again, most of the graphs when I put my pin as the upper right-hand corner will show, is about 6 millimeters off the articular cartilage of the femoral condyle, and the PM tunnel is about 8 millimeters. And if you, again, you want to leave at least a centimeter bone bridge between those two bundles so you don't have bone convergence. And when you're done, hopefully your reconstruction looks like that. I tend to make the anterior lateral bundle a bit larger than the posterior medial bundle. It helps to save some bony real estate between the two tunnels. And really, the anterior lateral bundle, as I mentioned earlier, is sniffing larger, so you're really reproducing the normal anatomy there. Now, in terms of graph fixation, I mentioned earlier the tunnel, which is the historically way of doing it. The problem with that is you have the so-called killer curve, where the graph comes through the tibial tunnel posteriorly and then takes a right-hand curve to the femoral side. There has been biomechanical studies shown in the lower right-hand picture there that that graph can actually stretch out over time. And so the advantages here of the inlay is it does reproduce normal anatomy because the normal PCL attaches on the bone there. You get bone-to-bone healing, especially if you use modern methods of fixation, and you eliminate that killer curve. Now, the disadvantages is it's technically demanding. Before arthroscopic methods came about, we had to basically flip the patient over twice. You'd start out supine, you flip them prone, you have to re-prep and drape, and then flip them back supine to finish. That's a lot of hassle. It takes us, in this OR that I'm at right now at Washington University, about eight minutes to do that. We've evolved completely to the arthroscopic procedure. But again, if you're not familiar with that or comfortable with it, you can't do it safely. You do have a risk of contamination, obviously, with breaking and sterility two times. And some patients, some surgeons are not very familiar with that posterior approach. And so those are some of the things that may turn them off of trying this. However, there's a lot of biomechanical support, again, that the inlay is actually stronger than the tibial tunnel because, again, this sort of killer curve concept. Now, this is the open reconstruction here. I'm going to show them out of this photo. There we go. So in terms of the upper left hand, you can see proximal and medial. You basically want to go to the interval between the medial head of the gastrocnemius and the semimembranosus. There's a very nice interval. You can retract the medial head laterally, and then you can use Steinman pins based on how much assistance you have that will keep those over that muscle belly over there. I typically make about a two and a half centimeter by one and a half centimeter bone defect there, and then fashion your graft. I tend to favor an Achilles allograft, but usually you only need one screw for fixation with a washer. Once you put it in place and hold in place with a screw, you then close the wound, you pass the graft intra-articulately, and then you put the patient supine and then fix it in the femur like you normally would. Now, in terms of the arthroscopic procedure, again, this is much easier. Those of you who do a lot of arthroscopic procedures, you will have a lot of familiarity with this. The advantages here, you avoid a large posterior incision, there's increased visualization of the tibial footprint, you do avoid the position changes with infection risk and cost of draping, it does cut down surgical time, there's theoretically reduced neurovascular risk, and there's less caps for disruption. And you can either use it with a single bundle or double bundle graft, whatever your choice is. In this example here, the double bundle graft with the tibial inlay, the tendon length here is between 65 and 75 millimeters long, and it forms a very nice strong graft. So here, just to look at sort of sequential photos here, always do this under C-arm, always use a 70-degree arthroscope. You really can't see all the way back down to that champagne configuration of the insertion on the tibia if you don't use a 70-degree scope, as shown in that left-hand arthroscopic picture on the left. Then I tend to use a flip cut or some sort of similar device to make a about a 20-millimeter socket. I tend to make my socket about two millimeters wider in diameter than my bone cylinder. I think it makes it much more easy to flip the graft when you do that. And then you can take from the posterior medial portal, you can take a switching stick or some sort of probe like is shown here, and basically run your sutures around that like a pulley, and it redirects the directional pull of your sutures as you're pulling that bone plug in place. And then once you have it in place in the tibial socket, you can fix it on the front of the tibia with whichever means of fixation you like, and then use your femoral fixation as you would with either interference screws or some other method of fixation based on whether I use one or two bundles. Now in terms of post-operative recuperation, basically break this down into six phases. The rehab for a PCL is slower than for an ACL. I want to emphasize in terms of knee flexion, I go pretty slow, zero to 90 degrees for two weeks, and then progressive weight bearing is tolerated based on whatever injuries there are. I do not allow patients to do isolated hamstring exercises for at least three months, because again, when you fire hamstrings, you are sort of pulling against your graft. They should have full range of motion somewhere by three months, and obviously weight bearing exercises, gradual introduction to sport-specific drills, and return to full sports anywhere from six to nine months based on what sports they had. But again, there is really no role for aggressive rehabilitation in these patients, and I think you'll find that your patients, they just tend to go a little bit slower than they do with an ACL. And if you have a rehabilitation person you're working with, a therapist who has not rehabbed a lot of PCLs, I would definitely contact him or her to let them know you want a little bit slower, that there's no awards to be won by getting full knee flexion over the first four to five weeks, because again, you have the potential to stretch out that graft. In terms of surgical complications, the incidence is up to 53%. Popliteal nerve vascular injuries, obviously the big one, the more you can flex the knee when you're, if you are going to do a trans-tibial tunnel, the more you flex your knee, the less risk you have of running into the popliteal artery. You can't have articular surface blowout, so again, if you use a double bundle construct, make sure you pass your pins in, you look at that femoral articular cartilage to make sure there's no risk of that happening. Compartment syndrome, if you have an extended procedure that you're not very familiar with doing this, or if you combine it with another reconstruction, you know, I would not make this your first case by doing this by yourself on a Friday afternoon in a surgery center. You know, get assistance, do it the first case of the day, do it in a hospital where you do have assistance if there is a neurovascular risk. You can have persistent postures sag, you can have loss of flexion due to inaccurate tunnel placement, overtension of the graft, fixation, extension, or inaccurate tunnels, just like you would with an ACL or any other reconstruction. In terms of the literature that's out there, comparing, again, there's a lot of literature, none of it's particularly great because they're often comparing different types of bundles, different types of fixation, different types of grafts, combined acute and chronic, so there's a lot of apples, mixing apples with oranges, and so really the literature is not all that great compared to what it is with the ACL. But if you look at, at least look at the double bundle versus single bundle biomechanical analysis, a meta-analysis of 10 biomechanical studies showed the posterior laxity was significantly improved with a double bundle. In terms of the clinical results, systematic reviews and meta-analysis of 11 studies published by Collet in 2017, both groups, single bundle and double bundle, improved in posterior tibial translation and patient-recorded outcome measures. The double bundle group power improved significantly with objective posterior stability as measured by the telostat bias as well as the IKD-C scores. So from my personal standpoint, I've evolved from going to trans-tibial single bundle, I first went to doing the double bundle, then I evolved to doing the inlay procedure, first open and then arthroscopic, because again my stability I think improved, got a full range of motion and was just more reliable over time compared to what I was getting with a single bundle graft placed to a tibial tunnel. So I know I went kind of fast with that, I will stop just to keep us on time and thank you for your attention. Thank you, Matt, that was great. We'll press on to the next topic. Dr. Bernholt is going to educate us on the lateral side of the knee next, so take it away, Dave. All right, thank you, Justin. Let me get my slides shared over with you all. All right, so I'm going to take us through the lateral side of the knee. We're going to kind of go quickly through exam imaging, all that, I know most of us are pretty familiar with that, but just quick definition, posterolateral corner, most of the time for purposes of reconstruction, we're going to be talking about the fibular collateral ligament, popliteus tendon and popliteal fibular ligament. There's other structures that comprise the posterolateral corner, but again, usually that's the three we're going to talk about the workhorses for for this particular injury. So less common than ACLs and MCLs, but still not terribly infrequent, approximately 16% of all ligament injuries of the knee. Isolated posterolateral corner or FCL injuries are fairly rare. If you take a 15% rate in that kind of range that's given there, multiply that by 16, you're looking at about 2% of all ligament injuries you'll see is isolated. So these are often combined with cruciate ligaments. The take home point of that is, if you know that the posterolateral corner or FCL is injured, carefully look for other injuries, whether it's bony injuries, whether it's other ligaments, they're not all as obvious as this gentleman who showed up in our emergency department. But you want to scrutinize your imaging, you want to have a good examination. So this is a patient I saw just a couple months ago, who came with an MRI read saying intact PCL. Again, you can see on this MRI image, the fibular collateral ligament evolved off the fibula. So again, high index of suspicion, you can see this PCL to me didn't look very intact, confirmed on axial slices and confirmed on exam. And at time of surgery, it's just good to have this on your radar to make your operating room experience as straightforward as possible. So there's no surprises. So for examination, various stress will will best test our fibular collateral ligament. There's an example of you know, at zero and 30 degrees, you got to be careful to make sure you are centered. When you are starting to test if the MCL is out, you have a significant medial sided injury, you can get a false positive, you can get the similar effect when you're looking at external rotation. You know, whether via dial test or posterolateral drawer, you got to be beware of false positives with MCL or PLL deficiency, really try to pay attention to whether it's the intermedial motion or posterolateral tibial motion, prone testing for dial is more sensitive. The other physical exam maneuver I will utilize frequently is external rotation recurve bottom test, you pick up the lower extremity by the great toe. And if positive that the tibia will spin out into external rotation, the knee goes into recurve bottom, you can measure the heel height compared to the contralateral side, this should raise your suspicion for a combined ACL posterolateral corner injury if asymmetric. So imaging, you know, we get radiographs on everyone, a lot of times these are normal for lateral sided injuries, you want to look for arcuate signs, you want to look for lateral compartment diastasis, there's a smaller arcuate sign, there's a bigger one and obvious lateral compartment diastasis, this is a no brainer that the lateral sides injured in this setting, most of the time, the MRI will serve as our workforce for imaging, it's more sensitive when acute, you know, for the high grade injuries, such as the one pictured here, it's pretty obvious, you know, this particular image, there's not much still intact on the lateral side. It is of note for lower grade injuries, if you're looking at an isolated fibular collateral ligament injury, sometimes they can appear normal, particularly when chronic. So here's an example of a patient who are sorry, this is we're going to go quickly through just some positive imaging findings. This is fibular collateral ligament, the popliteus is fairly easy to track and find on your your coronal views. On the right where it's circled, you can see where the popliteus is not attaching, where it should be in the sulcus. And then here you can see retraction distally of the popliteus. The hardest of the structures to see is the popliteal fibular ligament, you can see it. But sometimes you can't, you can't see it, the slices miss it, you know, a lot of these images, at least in my practice are coming from our trauma center where the MRI scanners maybe not as high quality as you want. Sometimes you just don't see these, this particular structure. So stress imaging really helpful when MRI is unclear, particularly with chronic injuries. This is a patient who had an isolated fibular collateral ligament injury, you can see some abnormality as the fibular collateral ligament comes distal, some interstitial kind of change, but still in continuity. When you do a stress exam, there's 2.7 millimeters of widening. You know that that kind of fits for an isolated fibular collateral ligament injury. With more severe grade three PLCs, you're going to feel it on exam, but where I find these are really helpful are the combined ACL fibular collateral ligament. And so those are kind of your numbers, 2.7 are the updated number, 2.2 on stress. So moving to treatment, so conservative management is indicated for all grade one injuries and then selected grade two injuries, isolated injuries and low demand patients. And again, this is not based on the imaging finding, this is based on the the laxity on exam. So surgical treatment, all grade three injuries and then grade two injuries that are isolated and high demand patients or patients with displaced bony avulsions and then in grade twos and any combined injuries, so the multi-legs. So why do we really need to pay attention to the posterolateral corner and multi-legs? We know that there's increased force transferred across the PCL and ACL grafts in the setting of posterolateral corner fibular collateral ligament insufficiency. So there's a much higher chance of failure and graft fatigue. So always address in a multi-leg. And for this reason, I try as best I can to single stage all of my multi-leg reconstruction. So I don't have a period of time where some grafts may be getting undue force due to insufficiency at other areas of the knee. We're going to go into some details of surgical treatment now. So timing, it's well established in the literature that patients do better when these are addressed within three weeks of injury. It's going to make your dissection easier. That soft tissue window has more ability to kind of heal under the appropriate tension. So address these early when possible. In the multi-leg setting, I typically try to get into these about roughly two weeks, just inside two weeks to allow some reconstitution of joint capsule, prevent extravasation of fluid. I go sooner sometimes. So the pictures on the right, you can see this is a patient. On the lower image, you see a high-grade lateral-sided injury. And then up above, you see a distal pole patella fracture. So this I bring to the operating room a little quicker. And then I always look at the proximal fibula because I don't want my fibular tunnel to be compromised in a reconstruction. So if there's significant signal or a fracture line, you got to tread lightly. Sometimes these need, you know, a good six to eight weeks to kind of heal in a little bit before you want to chance it and risk blowing out the tunnel. That's not for all proximal fibula issues. Here's an example of a proximal avulsion. You can see it doesn't track down as far distally. And so you can adjust your tunnel. I adjust it just a little more distal than I otherwise would. And these images here are also a great segue to the next topic, which will be on when we do repairs. So you can see if you look from left to right, the fibular head appearance looks more normal on the right. So not only is there reconstruction tunnels, but also repair. So when do we do a repair? These are two off-quoted studies that suggest that in most cases, recon is going to be our go-to for posterolateral corner injuries. The caveat is bony avulsion. So for all comers, when you look at it, failure rates 37 to 9 and 40 to 6. So repairs do not fare as well. The ideal indication for repair is going to be a bony avulsion with adequate bone to allow fixation. Here's an example of one done with a screw and washer. You can use anchors. You can use suture through bone tunnels to conduct the repair. This indication, there was consensus in the 2019 posterolateral corner recon expert kind of opinion article that this is the one indication that everyone agreed on for repair. Here's some images showing a repair using reduction forceps to help with the reduction with the knee and extension, and then a screw and washer to reduce the fracture down. Repair does not always have to be reserved as the primary use. You can use it as augmentation. Here's an example of a patient with a biceps femoris avulsion. And it's hard to see in this video, but there's a PFL avulsion, a couple of bony fragments down there. And so I used a combination of sutures through bone tunnels and suture anchors, the suture anchor for the biceps femoris, a little 1.9 millimeter double loaded anchor, use modified Mason Allen stitches. And you'll see as you pull on your post, you start to reduce the biceps femoris down. You couldn't see as well the popliteal fibular bony avulsion coming down, but that also reduced down through the same mechanism. So again, anchor or suture pass through recon tunnels can be used. I routinely repair any biceps femoris and then any repairable bony avulsions of ligamentous or capsular injuries. And then the, this images I had showed earlier, that's these, that video came from this particular patient and you can see how you reconstitute the normal anatomy of the fibular head by doing that bony repair. So now moving to reconstruction, there's largely two categories, tibial based or fibular based. We're going to talk about that in the slides that are forthcoming. So autograft, allograft, there's data suggesting that there's no difference in outcomes for allograft versus autograft. I routinely use allografts. There's usually, if I'm going to use in the setting of a multi-leg, I'm going to reserve my autograft for the ACL and I use MCL techniques where I often use autograft. So I routinely do not use autograft for the posterolateral corner. So types of reconstruction, there's tibial based, your anatomic reconstruction, laprod techniques. So we reconstruct all three primary PLC components through two femoral tunnels, a tibial tunnel and a fibular tunnel. This is more technically demanding. You have to avoid over-constraint, make sure you're tensioning a neutral rotation. Here's a couple of different ways that I will do laprod depending on different variables, graft prep help, and whether grafts are covered or not. So you can do it with tibial allograft times two, it's more expensive, but there's less graft prep time. There's peak screws in the tunnels in this situation, both in the tibial tunnel, fibular tunnel, and then femoral tunnels. And then this is the classic split Achilles bone block a la laprod technique, less expensive, but there is more graft prep time. So then moving to fibular based reconstructions, non-anatomic fibular based, the Larson technique is one of the earlier techniques. It's a single femoral tunnel. It's less technically challenging. I don't routinely perform this. You could consider this for an isolated FCL. I typically just do a single limb FCL without both limbs coming back up to the femoral side. And then there's a fibular based Arciero technique that uses the same two femoral tunnels as a laprod technique. Doesn't truly reconstruct the popliteus. It's not truly an anatomic reconstruction. So pros of this though, you can do this with a single tibia and allograft is what I routinely do relatively low cost and low prep time. You can use, I typically use interference screws. Peak screws have worked well for me. An adjustable loop button fixation is reasonable as well. I've not found any need for suture augmentation for these. Looking biomechanically, there have been a few recent biomechanical studies here in the last six or seven years showing that there's no, in the lab at least, no difference in varus stability or external rotation stability with a laprod versus an Arciero. And it's surprisingly actually neither reconstruction technique effectively controlled proximal tib-fib joint stability. And then looking clinically, you know, similar to what Dr. Matava was saying about looking at PCL outcomes, there's really not very many high quality studies, comparative data to look at tibial based versus fibular based. Two recent systematic reviews have showed no clinical difference. But again, these are typically not high number of patients and not high quality comparative studies. So my algorithm for fibular collateral ligament only, I'll reconstruct with a tibia allograft for posterior lateral corner without tib-fib joints instability. I will do both Arciero and laprod depending on OR resources, how much help I have with graft prep. If I'm relatively low staff, then I will go for an Arciero. And if I have hands on deck, laprod is reasonable to do. And then if there's tib-fib joint instability, I typically will do a laprod. This is, again, there's no biomechanical or clinical data to back this up. Just what makes the most sense to me. And then some quick pearls. I do a slightly curved incision. I do like it to be straight in extension. I don't use tourniquet. I like to do my dissection prior to arthroscopy to prevent fluid extravasation, which can hurt your dissection. Just now we're talking about common perineal nerve late in it, but this is an important topic for posterior lateral corner injuries. There's a high rate of these occurring 15 to 40%. I routinely will get the common perineal nerve out. And if you want to be doing a lot of lateral sided work, I consider offering your services for non-traumatic common perineal nerve neurolysis procedures. So our foot and ankle providers here routinely send me the foot drops. There's going to be a lot more of these coming from the rapid weight loss people are getting with those Zempik. But the reason why this is good to be comfortable with is if you're comfortable with normal, you can handle abnormal. So you can see the blue dash marks here. This is a patient where as I'm dissecting this, it's just not following the normal anatomic course. You can see the biceps femoris evolved, and you can see this hairpin turn that if you don't know what the normal anatomy is, it's easy to end up going right through the nerve there. And then just a couple other pointers. Floral can be used to help. I think it's really helpful, especially for the tibial tunnel, just to make sure early on when you're starting out on these, making sure you don't blow out laterally, making sure you don't go into the articular surface, but it can give you useful information. Know your tunnel trajectories to prevent convergence. And then the final little plug here, being down in Memphis, is don't run away from high BMI. These patients, this book got published out of Campbell Clinic in 2011 before I got here, but patients not operatively treated with multilig knees do not do well. You can see the differences in Leisholm 67 versus 52. This is unpublished data. We're working on beefing up our numbers with follow-up a little bit more, but we found that the high BMI patients based on our data actually do as well as our lower BMI. And the big discriminator who didn't do well when looking at our series was age, which actually tracks well with the Mayo data. So that's what I have on this topic. Last little thing, for chronic injuries, just be aware, HTO may be needed prior to reconstruction. Post-op rehab, touchdown weight bearing, begin early range of motion, zero to 90 degrees. All right, thank you. Thanks, Dave. All right, we're going to traverse over to the medial side of the knee with Armando Vidal. So, Armando, you can take it away. All right, Justin, thank you. Let me get my screen share up here. Thank you, Justin, for the invite. Thank you, AOSSM, and thank you all for being on this webinar tonight. I've always learned a lot. I got a big PCL poster a lot of corner tomorrow, so thanks, Dave and Matt, for the pearls. I think they're really helpful. I think I made a mistake when Justin was soliciting topics. He said, Armando, what do you want to do? And I said, I'll do whatever you want me to do. And I took the medial side. And I think when I was a resident and a fellow, the dark side of the knee was the lateral side. You know, we didn't understand it. And guys like Rob LaPrague really helped us understand the anatomy, the biomechanics, the surgical options. I think we're there with the medial side. I think there's still a lot unknown about when the medial side needs to be addressed. We're not there yet, but I think the medial side needs to be addressed. What's the optimal reconstruction? So I think the medial side is, we're at a point now where we probably were with the lateral side, you know, 15 years ago. I don't have any disclosures as they pertain to this talk, but a couple of background information. So the MCL, as you know, is the most common ligamentous injury in the knee. We see it in hockey very commonly, especially college hockey, football, skiing. And if there's a take-home point from today's talk is that the majority of these injuries can be treated non-operatively. I always think there's a little bit of risk when we start talking about surgical management of MCL injuries, because I see a lot of over-treatment. I live in a ski town. Almost every ski ACL is ACL-MCL. And I can't tell you how many ACLs get treated, the MCL side gets treated surgically, and these patients end up with stiffness, arthrofibrosis, lack of isometry. And I've seen far more patients that have been over-treated for MCL pathology than under-treated for MCL pathology. So I think if there's a take-home point is that you can get away with a lot on the medial side. There is controversy about the severity of injury that can be treated non-operatively. And we're really going to focus on multiligamentous knee injuries, because in almost 20 years of practice, I have yet to ever treat an isolated MCL. I still, to this day, have never done one that was purely in isolation. I think the tendency, and I think the reason we are confused about the MCL is I think there's an oversimplification of the vernacular, right? We talk about the posterolateral corner, we talk about the two bundles of the PCL, and then we just talk about the MCL as if it's one structure, but it really isn't. I actually prefer the term medial complex or medial side complex, because it's really a combination of three structures. You have the superficial MCL, the thing that, you know, the structure we typically refer to when we say MCL. You have the deep MCL, and then you have the posterior oblique ligament. And that posterior oblique ligament has an important rotatory role, and usually that injury to that structure can be the defining force onto whether or not you're going to need surgical stabilization. The superficial MCL is also not just one band-like structure. It has two different insertions on the tibia. If you're going to endeavor on a reconstruction or repair, I think it's important that you reconstruct both of these, or at least restore both of these. It has a proximal insertion, which is about a centimeter and change distal to the joint line, and then you have a distal insertion, which is just distal and beneath the PES tenons, on average about six centimeters distal to the joint line. The deep MCL is interesting because there's a lot of discussion now about some of these structures, particularly the meniscal tibial ligament. It's influenced on meniscal biomechanics, on meniscus root tears, but it's a capsular thickening that inserts very proximal or very close to the joint line. I think an important structure to understand is the POL, or the postorbital complex. Its origin is just distal and anterior to the gastro-tubercle, as you can see in this outline. And it inserts just anterior to the semimembranosus insertion. It has three arms, and it has an important restraint to internal rotation. And as Dave was talking about, when you're looking at a dial test, you can be confused. You know, because sometimes postrolateral rotatory instability can be confused with intramedial rotatory instability. So a thorough clinical exam and stress radiography, I think, is important to help determine which side is out. And obviously it has a restraint to valgus at zero degrees of extension. The challenge, I think, is that historically, we have pretty limited grading for these MCLs, right? So we often talk about, is it a grade one? Is it a grade two? Is it a grade three? That's based on AMA classification, right, from 1966. And I would argue that it's very subjective. It doesn't really correlate very well with severity of injury, propensity to heal, or surgical intervention. So it's, I think, somewhat outdated. An endpoint, the presence or absence of an endpoint, we still talk about, but to me, one of the most important clinical exam findings, and I'll discuss in the next slide, is opening and full extension. We're taught on the OITEs and the boards that that's a reflection of a cruciate injury, but it's also a reflection of a posttraumatic complex injury. I think the challenge is with ACL MCLs is sometimes they don't actually regain full extension in the office. So trying to force full extension and testing that posttraumatic corner, I think, is important and then being able to determine antramedial rotatory instability. So what are the important exam maneuvers? Opening and full extension is super important because to me, that probably won't heal and is often a driver of surgical intervention. Obviously, if you're a classic 30 degree or 20 degree valgus stress test, for antramedial rotatory instability, you do an antramedial drawer. So you externally rotate the foot about 15 degrees, bring it to 90 as if you were doing a drawer on a PCL, and you can assess for that antramedial rotatory instability. I think that validating or quantifying your exam is actually very important. So I tell our fellows all the time, I've been fooled. I've had a patient that I was convinced had a lateral-sided injury based on their mechanism. And actually, when we stress them in the office, both in varus and valgus, it clearly was their medial side. And there's some complexity to that patient. He had had previous medial-sided surgery that I didn't pick up on. But I think stress radiography, both in the medial and lateral side, one can create an objective exam. So it takes what you're finding on exam, which I feel like is more of a screening tool, and objectify it. And it also tells you a little bit about the severity of injury. And this is based on a cadaveric sectioning studies that were performed here in Vail by Dr. Leprod years ago. With 3.2 millimeters indicating a complete superficial MCL tear, and about 10 millimeters indicating a complete medial-sided injury. I think the importance of what I tell our fellows is, this tells you the severity of the injury. It doesn't tell you about the propensity to heal. Because as opposed to the lateral side, the medial side does have some capacity to heal. But the presence or absence of this, or the asymmetry here, can help objectify your exam. And I would strongly recommend stress radiography if you're gonna consider surgical intervention on a collateral ligament, and on a PCL. Now, the reason it's confusing is because historically, non-operative management has been endorsed. In fact, you could make a compelling argument to treat none of these surgically. Now, in the 1950s and 1960s, immediate surgical reconstruction was recommended for grade three injuries. In the 70s, it became very evident that even in high-level athletes, these patients could do better with non-operative management. In the 80s and 90s, and there are now several prospective randomized studies showing that non-operative management has equal PROs and less complications. Pete Indelicato showed us that in a high-grade population, both a collegiate population with high-grade injuries, which he has, again, defined as greater than 10 degrees of opening, these patients can do well with non-operative management. So you may ask, where is the controversy? Should I treat all of these conservatively? Now, the problem is that we have conflicting and overlapping classification schemes, as I indicated earlier. You'll see papers that talk about high-grade injuries, but there's no consensus on what actually constitutes a high-grade injury. Some, like Pete Indelicato's work, indicates greater than 10 degrees of valgus opening. Others indicate a high-grade injury is valgus instability at zero, and they may not be the same. Because again, valgus instability at zero typically indicates a compromise of the posterior medial complex and the posterior oblique ligament. So the challenge is that we're not all speaking the same language when we're talking about high-grade injuries, as you interpret the literature. We've looked at this, Matt Motava was part of this in our MOON group. We looked at our outcomes of grade three MCL injuries treated concurrently with ACL. This was a, you probably are all familiar with the MOON group. It's a multi-center ACL study group. And I'll draw your attention to a couple of things. We defined high-grade, or grade three, as opening and full extension, which again, to me, is a driver for surgical intervention. Only of the patients that had greater than two years of, or 85% had greater than two years of follow-up, only 1.1% in this multi-center group of highly trained knee surgeons ultimately underwent surgical intervention. So it gives you an idea of how many of these patients actually require MCL intervention in the setting of a combined injury. The interesting is that there was no significant difference in outcomes between the operative and non-operative group. In fact, the operative group, if you look at it critically, did a little bit worse, but was underpowered to make that assessment. And the argument could be made that the majority of these should be treated non-operatively, but if you look critically, I think we all agree, there's probably a subset of these patients with severe combined injuries that would benefit from operative management. However, that population is yet to be defined. So I think one of the other take-home points from this talk today is that we still, we need to do a better job at defining what is the population that requires surgical intervention. So you could say, well, I'm just gonna treat them all conservatively, but what do you do with a patient like this, where they have a tibial-sided injury that's incarcerated in the joint, meniscal extrusion? You can see a huge gap arthroscopically. You can see the folded MCL injury at the time of arthroscopy. I think we'd all agree, this is probably one that won't do well with non-operative management, needs to be flipped out of the joint and either repaired and or reconstructed. Or a patient like this, where is the MCL? In fact, where's the medial epicondyle? You can't even see it. And the reason you can't see it is because it's a bony avulsion incarcerated in the joint. I think we'd all agree, this is clearly not a patient that could be managed with conservative intervention. So when do I operate? What's my approach? Well, again, I'm a minimalist. I think there's quite a bit of variability amongst experienced knee surgeons about who requires surgery and doesn't. For me, it's combined instability with a POL or post-tubule cord injury. And I define it on exam by opening and full extension. I do think there are some grade three tibial-sided lesions encountered at the time of ACL, particularly ones that have interarticular ligamentous entrapment or a stentor lesion that you can repair with relatively low morbidity. And you need to reduce those because they won't heal, especially a stentor lesion that has no direct apposition to bone. For me, again, valgus instability at zero is an indicator that I need to consider surgical intervention. And certainly chronic symptomatic medial instability. Let's say it's an ACL MCL or a PCL MCL where the MCL was left alone. And they have chronic instability that is symptomatic and confirmed on stress radiography. I think we'd all agree that those are ones that ultimately require surgical intervention. Now, are there some guidelines other than just clinical exam findings? This group out of Japan looked at the severity of the injury on MRI. They took a group of, I believe it was about 17 patients with high grade three MCL injuries. And if they had diffuse involvement, like you see here, where is the zone of injury? Is it femoral? Is it tibial? I kind of see injury diffusely. A lot of those patients had latent instability and ultimately required delayed surgical intervention. Again, a relatively small cohort. What happens if you have latent MCL instability? Well, it kind of makes sense as you drift into valgus, that's gonna put increased loads across your ACL. And that's been confirmed in cadaveric studies. So I do think if these patients open up in full extension, if they have diffuse injury with asymmetry and valgus stress x-rays, you should consider surgical intervention. And we need to talk a little bit about what are the pros and cons of either repair and or reconstruction. So when do I repair? Well, similar to the post collateral coroner data, I do think recon seems to do better than repair in general, if you take a 35,000 foot view. But for me, if it's a lesion like this, where it's predominantly tibial sided, the tissue quality is good. You're getting to them acutely. It's actually very hard to do these after three weeks. I would consider repair with some sort of suture or graft augmentation. And this was looked at by Robin Pratt and their group. This was a prospective randomized trial looking at augmented repair versus reconstruction. And what they showed is that there was really no significant difference in terms of stability, but the reconstruction group actually had higher PROs. So similar to the lateral side, I do think in general, reconstruction is favored over repair with the exception of a very small niche cohort, as I just described. How about repair versus reconstruction? This is a systematic review also done by Jorge Echala. They looked at 18 studies, 503 patients, both repair and reconstruction improves PROs, but they can develop stiffness and or failure. And it was actually more common, believe it or not, for stiffness and arthrofibrosis to develop in the repair group. So I have a low threshold to reconstruct if I feel the MCL is incompetent, with the exception, again, of those groups that we just talked about. So how do I do repairs? This is an ACL with a tibial sided lesion. This ligament I'll propose to open was in good shape. I did a BTB ACL. I think that's a more stable, stiffer construct. Unfortunately, I don't have any open pictures and we will reconstruct both the proximal and distal arms. And you can very subtly see, you probably can't see my cursor, an anchor point very close to where that tibial fixation screw is, or sorry, where that tibial interference screw is for the ACL. How about more diffuse injuries? For injuries that are not open to repair, such as this injury, where you see diffuse injury, proximal, distal. This has a post-tributal complex injury opening in full extension. You see edema in that post-tributal corner. I'm gonna do a reconstruction. I do think it's important to restore both the superficial and deep MCL, as well as the rotatory component. So you can see this valgus stress x-ray fluoroscopically to the left. You can see a dramatic drive-through wherever you can see both the undersurface and the meniscus capsular junction of the meniscus. That should grab your attention as you see here arthroscopically. I do think it's important to use radiography to identify your isometric point. I joke with our fellows that the MCL is the easiest ligament to reconstruct, but the hardest to get right. So I will find the thermal insertion fluoroscopically. I like to use suspensory fixation so I can modify my tensioning. I will put a suture anchor at 1.2 millimeters from the joint to reconstruct that proximal insertion. And then I typically will either use an interference screw, or in this case, a screw with a spiked washer to reconstruct its distal attachment. And I found that to be a very effective tool. And you can see the difference in stress radiography both pre and post on this case. Now, you may say, Armando, we just talked about one of the drivers of needing MCL recon is that rotatory component. What you do for the POL. There are anatomic techniques that have been described. Laprada is the most famous. I think that those can be challenging because it requires two insertions and two drill holes in the femur and two on the tibia. And that POL insertion on the tibia can actually be relatively challenging. This is something that I learned from Chris Harder when I was a fellow at Pittsburgh. You see sutures here to the left in the POL. You can see that anterometer rotatory instability. You pull tension on it, and you can see how that's dampened out. So I will do a reconstruction as I indicated previously, and I will actually imbricate in a pants over vest fashion the POL. This has been studied by the group out of New Mexico, and they compared it to an anatomic Laprada technique showing similar outcomes in terms of stability. And I think this is a lot less morbid and a much easier reconstruction to do because that POL can be challenging and the anatomy can be challenging in these cases. So in summary, trying to keep us on time, the vast majority of MCL injuries do well with non-operative management. I think you're better off erring on the side of undertreatment rather than overtreatment. But not all MCL injuries in the setting of ACL or multi-leg are benign. I think you can consider primary repair with suture augmentation for high-grade tibial-sided lesions, assuming that the tissue quality is good. It does allow you to mobilize the patient quickly and protect your repair. I do think there is a push by industry recently to overtreat these lesions, and I would recommend that you, again, err on the side of benign neglect for the majority of the MCLs you encounter at the time of your ACL. If you have a diffuse injury, if you have a chronic injury, if you have a multi-leg PCL-MCL, PCL-lateral-side MCL, or if it's a revision, I think you should consider anatomic MCL reconstruction. And my personal technique is to reconstruct that superficial MCL with two points of fixation on the tibia and a POL imbrication to address the rotatory component. Thank you. All right, thank you, Armando. So we are right at seven o'clock, but Ashley informed me we have time for a few questions. There was one question in the group that I wanted to field live, and that was with regards to our lateral side. And the question was, do you have a quantitative method for determining tibiofibular instability so that way you can decide on a fibular versus tibial-based posterolateral corner reconstruction? So Dave, how are you determining whether the tib-fib joint is involved and unstable in these patients? Yeah, that's a great question. There's not a great, as far as I know, examination laxity criteria for it. There's some studies on the topic that will do a binary dislocatable or not dislocatable. It is kind of a gestalt. You feel enough tib-fib joints. And starting out, I examined a lot of them, just normal patients. Get the fibula in your fingers and feel how much it moves. And I do it on every posterolateral corner and just feel that normal motion. And so it takes building a little bit of your subjective feel of what is unstable. But obviously, dislocatable, if you can put that fibular head anywhere, that's unstable. But I don't know that there's an objective criteria. If anyone else on this call has any other thoughts, more objective or different than that, happy to hear. I'm the same as you. I think feeling normal ones, both in the exam room. And then also, I think, you know, while you have it exposed, mobilizing it, and it is a gestalt thing where some of them are wildly unstable and then where others, it's less so. So just like a Lachman exam or anything, I think the more you get your hands on it, the more you become used to it. And the good news is even if you can't feel it, as you alluded to, any of the techniques work just fine. So. All right. I think it's very subjective. It's interesting. You just kind of shuck it around, right? We don't have any way to objectively stratify that. There's no stress radiography for it. I think what's interesting is, you know, and you alluded to it, Dave, in your talk, is, you know, Skank's article was great, right? Because it looked at RCR versus Leprod. And in the setting of tip-fib instability, none of them and neither of them actually really worked well. I do think one critique of that paper, because I think about it a lot, is that they popped the tip-fib joint after the reconstructions were done, right? As opposed to before. Because if you think of like a tip-fib reconstruction, if you're just doing a tip-fib reconstruction, it's that third arm of the Leprod technique, right? It's a hole through the fibula in the back of the tibia. So I think when in doubt, and it's probably a third of multi-legs have some element of tip-fib instability, anchor it to the tibia, right? So I think it's subjective. And if you're concerned about it, you're probably better off anchoring it to the tibia so you have a stable foundation. At least that's my perspective. Great. Another question that came in. I'll kind of generalize it a little bit more. All three of you, can you give us what graft you're using for your MCLs, or medial complexes, we'll say. Armando, go first. Yeah, so this has been an evolution for me. I use an Achilles. I cut off the bone block, actually, because I like how it's almost like a quad tendon when you're doing an ACL on the proximal side. So I create that tunnel, like you saw in my talk. I prepare it like a quad ACL reconstruction with whatever suspensory fixation, and then fans out. And you saw the anatomic pictures. So it recreates it really nicely, that kind of more broad insertion. So I use Achilles with a bone block cut off. The bony side of it would have been on the femur, and then the fanned out part on the tibia to try to recreate that fanned out portion. But it's been an evolution for me. How many anchors on the tibia? I usually one. I use like an all suture anchor or something small, kind of pass it up like a mattress and sock it down. And I've tried staples. I actually find an old school four or five screw with a spiked washer to work really well. And it's remarkably, it doesn't create symptoms, and it's solid. And then I re-tension on the femur when I'm ready. Sure. Matt, how about you for MCL? Yeah, same thing, Achilles tendon, especially if I'm doing a double but to reproduce the posterior medial side. But I think it's plenty of graph. As you were saying, it does fan out. I like the proximal portion of the best, especially if I'm just gonna do a single replication of the superficial medial. It's a very stout graph. You got plenty of graph there. So I agree. Dave? Yeah, I'm the only one different than I do tibia most of the time if I'm using aloe. Seven millimeter tunnel usually on the femoral side and then screw and washer. It does fan out some, but not nearly as much as an Achilles. So it's not quite as broad. It doesn't reproduce probably as well. But I actually do a good number of kind of the laparot-augmented repair as well, where you take hamstring autograft, you reroute it with suture anchors distally, two suture anchors distally and one proximally for deep MCL. I really like that if there's a combined PCL, because then I take away some of the posterior pole of the hamstrings, especially if somebody, I worry that they're not gonna follow my protocol. Takes a little bit of that force away from them. And I've been really happy with that graft. You just have to really make sure you appropriately reroute it. So you're in line with the joint medially. If you leave it just at the PEZ insertion, it's not gonna do squat. Yeah, I kind of am a hodgepodge of all three of you, depending on the exam, the tissue quality, the graft availability. So that's great. Matt, one question for you on PCLs. We'll dive a little deeper. Can you comment on any techniques, curls, anything when a combined PCL and MCL, sometimes that like medial femoral condyle, the medial surface, there's a lot of traffic out there. Like, are you using a specific guide or drilling technique to make sure you don't converge on that medial femoral condyle, especially with a double bundle PCL? Yeah, typically I will do a double bundle. My tunnels are sort of, how would I describe this? Sort of anteriorly oriented in the sagittal plane in terms of my PCL. My MCL anchor is gonna be, I've done, if I had that combination, I'll typically use a suspensory tightrope type device so that you don't have interference screws bumping into one another. But I'll aim the MCL femoral insertion a little bit more posterior to the PCL. It's a good point. Tends to become more commonly in Dave's talk where he did ACL with post-traumatic coronary. But again, that's what I would tend to do in that situation. All right. I think that wraps it up. Any final thoughts, comments from our panelists, words of wisdom? Again, look for these injuries and then reproduce normal anatomy. Use a strong graft, no matter what you're talking about doing and start early motion. I think the biggest thing also is I would not try to promise the patients you're gonna be done with all this sort of stuff in six months. This can be a year-long process, especially with some of these multiligament injuries that Dave mentioned, especially with fractures. So I would lay a crepe on some of these and let the patient know that you're gonna be together for a long time. All right. Well, thank you again to our panelists and for all of those tuning in. We hope it was worth your time and you learned something. I know I sure did. And I hope everybody has a great night. Thanks a lot, Justin. Thanks, guys. That was great. Thank you, everybody.

knee ligament injuries

PCL injuries

fibular collateral ligament

popliteal tendon injuries

osteoarthritis prevention

early intervention

comprehensive assessment

patient education

graft failure prevention

knee stability restoration