All right, good morning everyone. Thanks for kicking off the meeting at 7 a.m. early on here and looking forward to a great program from Dr. Dickens. Appreciate him taking the time when he's super busy and the rest of the all-star faculty here. As you know, our topic is about posterior instability from simple repair to arthroscopic bone block and the guys here have really led the way in describing bone loss posteriorly from Dr. Preventer and bone blocks with Dr. Dickens and Dr. Owens really taught us a lot about failure of posterior instability and how it occurs and everything. So we really have got a great panel today. Dr. Waterman was stuck, couldn't make it. So Nick Trasalini's filling in for him. He says he's gonna do his best Waterman impressions. We're looking forward to that. So let's just get into it. We're gonna start with Dr. Owens talking about risk factors for posterior instability and then we'll move along down the line there where Dr. Preventer will talk about some arthroscopic techniques and then we'll talk about throwers with Nick and then Dr. Dickens will talk about bone loss a little more. Thanks, Justin, really appreciate you putting this together. I have the great task of talking about epidemiology and exam and don't get anything into the repair technique. I'm gonna leave that all to this great panel here. So I have a lot of stuff to move through, a little bit boring at the beginning, but we'll get to some techniques and we'll get to some cases at the end as well. I'm hopefully gonna share with you more about epidemiology of posterior instability than you ever wanted to know and I probably never wanted to share. I do have some, let's see, advance here. Okay, I do have a couple of disclosures, none of which are really relevant to this talk. So posterior instability is extremely common, as you know, and when evaluating young athletes, you should always be thinking about instability until proven otherwise, whether it's subtle anterior or posterior. You're not always looking for instability symptoms when it comes to posterior. Majority of people will actually just have pain. So posterior instability does not always equal a posterior labral tear and vice versa and then also the treatment is certainly evolving with arthroscopic stabilization, though, is still the choice most of the time. So how big of a problem is this? So there's certainly a large spectrum of instability. Carter Rowe estimated around 10% of all instability was posterior direction and he was pretty right. There was not a lot of epidemiologic work done at the time, but Dr. Rowe was pretty astute as he usually was. A lot of people will cite the Robinson study looking at posterior dislocations in JBJS and he has a nice incidence rate of per 100,000 person years. But again, this is pure dislocations and this is a trauma center. Majority of these were traumatic and a third of them were from seizure, right? But again, no mention of subluxation events, right? So again, if you're looking for posterior dislocations to comprise your posterior instability cohort, you're missing the bottom of the iceberg. When we looked at this in a series of West Point cadets that came in, one had a dislocation event, 11 had subluxation events. Again, this is the majority of what you're gonna see is gonna be subluxations. And again, it did comprise around 10% of all instability, so Carter Rowe was right. To put that in perspective, again, the general population with a posterior dislocation alone, one per 100,000 person years, and then in our collegiate athlete population, that dislocation equates around 24 times that, right? So a college population, you're definitely gonna see a lot more dislocations, but again, look at the subluxations, or a magnitude greater than that. So that's the bottom of the iceberg, or your subluxations, or even those that just have pain. One of our former fellows, Joe Lanzi, looked at this of epidemiology in athletes, and again, only half of them had subjective feelings of instability. The other half had pain only. So if you're looking for people to come in and tell you that their shoulder popped out of the back, right, you're missing people. So always be thinking posterior instability. An athlete complaining of shoulder pain, be thinking posterior instability. In-season athletes, we know less about, but John Dickens here, we did a three-service academy study, primarily looking at anterior instability. We did have 12, though, that had posterior subluxations. Majority of these were able to return a little bit quicker than the anteriors. Again, we have fewer bracing options than those, and the majority of them underwent surgery. Some folks report the incidence of posterior instability increasing. I would challenge you that it may not be. Posterior instability is not posterior labral repair, okay? So this paper from JT and others in Hawaii reports the increase in incidence of this over time, but John Dickens and I looked at this at another military population. Again, you're gonna see a lot more posterior labral repairs than you are posterior pure instability. Again, only around 10% of these are pure isolated posterior in that direction. But again, you can see a lot of combined labral injuries, especially in your anterior population. So you may be doing a lot of posterior labral repair. It doesn't mean they're posteriorly unstable. Does it really matter necessarily? No, but I do stress to my trainees to have an understanding of what the diagnosis is before you just go in arthroscopically. So again, posterior instability does not equal posterior labral repair. You wanna have a diagnosis before you enter that operating room, putting it all together on your imaging, their exam in the office, their history, as well as then their EUA, and then before you put the camera and look in. I've had many patients multidirectionally lax that complain of anterior symptoms and don't have any anterior noted pathology. They need a capsulography in the front, but sure enough at arthroscopy, they have a tear in the back. Yes, you fix the tear in the back, but again, their symptoms are anterior in nature, and that may impact your rehab as well. So all this work on epidemiology, again, we know young age, male gender, we'll talk a little bit more about dysplasia later on, but Jim Bradley really brought this to our attention, the concept of a glenoid version in his cohort, and he still has the largest cohort that continues to grow over time looking at, but again, a glenoid version is a huge risk factor. I'll share a little bit about a prospective cohort study that I did when I was at West Point, again, around 1,000 incoming cadets. We tested them all with baseline exams and with MRIs, and then followed them over time, and again, the largest risk factor, of course, was any history of prior instability. So if they reported anything in high school, again, they had a hazard ratio of greater than four, so extremely impactful there. There were only seven posteriors in that cohort, but to give you just a sense of what the impact is of version, which was the significant risk factor we found anatomically for it, it was a hazard ratio of 1.17, which, you know, for those of you in here who are used to reading the literature, 1.17 doesn't seem like very much, right? But one degree of increased retroversion resulted in a 17% increased risk of posterior instability. So that just shows you, really, the effect size of that version. Again, in our cohort, those that had posterior instability had a version around 18 degrees, and the uninjured subjects around eight degrees, which is what we've seen a little bit in the literature. So again, what's normal? In our study, negative eight, but most studies talk between minus five and minus 10 as being normal, and a few studies that show that those that are in the repair cohort, like Bradley, it was around minus 10, and this Priveterra study, it was around minus nine. So again, we're looking at about a five degree difference sometimes in retroversion. The question really is how much is too much. So what happens? What's the pathoanatomy of coming out the back? Well, again, as Bradley noted, majorities, 80% had labral tears. Some were just patchless capsule. Again, we've reported not just labral tears in the back, but also slaps, anteriors, and then sometimes 360s, especially in that football population. Again, you can have a reverse Alps lesion, again, the Kim lesion, some of them are non-displaced tear between the labrum and the glenoid. Reverse hull sacs are uncommon in subluxation patients, but you do see them in dislocation patients. And bone loss is, we'll talk a little bit about bone loss. There is a little bit of a difference between bone loss and dysplasia, okay? Often the bone is not lost, but it was never there to begin with. Just because you have a posterior labral tear or a reverse Bankart does not mean you do not have a reverse Hagel. I have two cases in my career so far that I'll share with you that I know of. They may be more of seeing me than I've seen them, but two with, again, a large capsular tear, right? In addition to a posterior labral tear, there's a small labral tear, again, with a reverse Hagel. So you can see, just because you're so excited, you go and you see the tear, don't forget to do a thorough exam because you can see more. As we mentioned, bone loss is usually traumatic, okay? There may be a medialized bony reverse Bankart, but most of the time that I see bone loss is really more dysplasia and that the bone was really never there to begin with. Dysplasia is a complex three-dimensional problem and we, as surgeons, tend to reduce it down to a very simple two-dimensional metric, which is version, which can have a lot of variability in how you measure it, whether it's MRI or CT. But again, I just share, it is a complex three-dimensional problem and I think we're just beginning to scratch the surface of understanding truly the impact of dysplasia. But certainly retroversions, what we talk about most of the time, again, as I mentioned, five to 10 negative is usually around average. There have been some that have suggested, again, this Eichinger, Tiger, Lee, a few others, in this study in JV Jess suggested that 10 degrees was a risk factor for failure with a soft tissue procedure alone. I would challenge that that is not appropriate and that majority of your post-surger cohort will be sitting at around 10 degrees. So how much is too much? I'm not really sure. I get asked this question a lot. My opinion is that it's around 25 degrees or so is an appropriate cutoff for doing something bony, but I don't have any data really to support that right now. It's definitely, you know, when you see it, usually, again, like in this image, they're usually subluxated out the back and these are ones that I would do a primary bony procedure on and not wait for a soft tissue procedure to fail. But we're gonna hear a little bit more about some of the bony work that's being done by this great panel. Beware dysplasia. Again, I haven't had a video. I just realized this morning it didn't come across, but up top, you know, I show with just simple forward flexion, this guy goes out the back, as you can see, a CT scan. If they don't have a rim to go over, right, it's dysplastic and you may have a soft tissue repair failure. Again, this is not a posterior load shift. This is just raising him in forward flexion and he goes completely out the back. So how much is too much? Again, there has been some basic science work in this regard and, you know, we're fortunate to have Matt and Justin here who looked at bone loss and found that around 25% was significantly unstable with just a soft tissue repair alone. And we looked at this as well in our lab, again, found around 20% to be a significant drop off. So again, if you are experiencing, if you're measuring a bone loss, if you are experiencing, if you're measuring it and you're coming in the range of 20, 25%, this is when you want to start thinking about a bony procedure. So what is the role of the acromion? I bring this up now, it's still a little early, but there is some work in this regard. Christian Gerber, who has led us in many aspects of looking at anatomy, has really talked about the importance of posterior acromial morphology. John Dickens has a recent study as well in GSES last year, and they found that around 90 patients with instability, those had a flatter acromion, certainly had a little bit more bone loss. So I want to raise this concept of this posterior bone block described by Scafinelli in 2006, again, a very small cohort study, but the question is, yeah, sure, a flat acromion is a problem, so how do we fix it? Well, this is one potential option. I just shared this because in our lab, one of my residents, E.J. Testa, just published this, came out in July of this month of Arthroscopy Journal, but a cadaveric model looking at that posterior bone block and found it to be significantly more effective than labral repair, but again, still a lot more to be seen and very little clinical data on that. So I want to go quickly through my workup so that the other speakers don't have to talk really about the exam, et cetera, but I really start with history. It's really important to listen to these patients. Pain, as I said, you have to elicit sometimes, and if you're expecting them to come in and tell you that they popped out the back and someone put them back in, you may be mistaken. Also, if they come in with a history of being reduced in the emergency department, I've seen plenty of patients, and I'm sure you all as well, that have actually went out the back and it's pretty clear in their imaging and exam, but of course they report being, if all the ER notes say anterior dislocation event because the ER doctor doesn't really have an idea, even though they're lucky to get it back in. Elicit a clear history of a traumatic event, whether it would return the same day, again, solicit pain in that forward flex adductive position, pushups, bench press, football alignment, and again, you wanna be on edge for any history of voluntary instability or any sort of seizure disorder has to be managed prior to any surgical approach. You have to completely inspect them, especially women. You have to, if they don't have a sports bra, step out, get them a gown because if you don't, you'll never see scapulothoracic dyskinetic motion in these patients if you don't look for it. If you just look at them from the front, you'll never see it and you don't have to worry about it, but it's endemic in posterior instability patients. So again, you wanna have a thorough neuro exam, of course, cuff, biceps, all of that. I really rely on the posterior apprehension. The JERK test and the KIM test can be very helpful as well. I really rely a lot on the load shift. I will note, you wanna do this in the position that you're gonna be doing your EUA and I'm a beach chair position, so I'll do it in the seated position, but I always start with the normal side, and as Dr. Lintner and others have shown that in a young athletic population, this can be grade two plus load shift can be physiologic. So you always wanna start on the normal side and then go to their pathologic side. And it's important to list the symptoms as well during that part of the exam. The GEIGE test, I do use and I found it to be very helpful, especially in Hagels or reverse Hagels, and basically you wanna hyper abduct the arm. There will be a check rain at about 105 degrees. I don't always find it to be a positive in my patients with a small KIM lesion, et cetera, but if they do have a IGHL disruption, there oftentimes will be positive, there'll be a side to side difference. I do incorporate a simple bite and scale. You wanna have a sense of what their generalized ligamentous laxity is and what their collagen is like going into this. That may titrate your capsular placation, et cetera. Your basic imaging, standard radiographs and MRI, certainly if it's acute, the hemarthrosis can provide some cap contrast. I am definitely a contrast guy though. Any delay in this and I will always get gadolinium. I find it to be especially very helpful for these subtle posterior labral tears and especially the Hagels. I think you miss sometimes unless you're putting gad in. Again, this is a reverse Hagel. You can see the extravasation on this SAGE view, but I do find the coronal views are best to look at this. And I find that this is one thing that I miss unless I really get the gad. Other imaging tips, when in doubt, get a CT scan. Certainly any suspected bone loss, dysplastic patients, or any revision patient, always get a CT. And that is really the gold standard for measuring any concept of bone loss. That's all I have right now. Hopefully I'm happy to add some stuff on at the end. We'll have some cases to show as well. Okay. Thank you. Thank you. And that next? Yep. Okay, so we have Dr. Provencher next, who's gonna talk a little bit about how to repair these. I should bring it up. Sweet. Awesome, thanks. Thanks a lot, Brett. It's an honor to be here in this great panel and learn so much from people like Brett and John. And I would say that the journey continues. My disclosures are available online. I'm gonna skip over a little bit of this stuff, but it's missed often in physical examination. It's vague shoulder pain. A classic patient comes in, 24-year-old, had a subacromial decompression. They're not better. They don't have impingement at a 24. They have something else going on. A lot of times, posterior instability. It's discomfort, it's vague, but it's also provocative. They don't do as many pushups. They don't do as much bench press. They have all kinds of other issues. This is a study we did looking at the difference between anterior and posterior instability, and we had 100 patients in each, and the primary complaint was instability, obviously, if you're out the front, and pain if you're out the back. There was really no primary mechanism and not a lot of subluxation, dislocation, actual events, a lot of repetitive microtrauma. And so you can sort of see this here of how these are totally different animals, probably because of the muscle forces, the scapula, the mechanics of the capsule, a lot of other things. It has to do with a lot of these stabilizers. The exam, this guy doesn't, he sort of doesn't like doing it. He's kind of shaking it off. He doesn't like it. He's like, ugh, he's kind of got that grimace, but he's like, I asked him to do it twice. He, there he is before surgery, but classic posterior labrum lesion. The posterior capsule is much, much weaker than the anterior capsule, and that's part of it. And then when you're starting to look at tear type and how to fix these, we've actually looked at how tear type matters. And this is a publication we did looking at shoulder and elbow score, SANE score, WOSI score, in terms of whether you had a full tear, chem lesion, or a bucket tear of the labrum. And guess what? Tear type matters. If you had these kind of chem lesions or flat buckets, you just didn't do as well as a clean labrum tear. Kind of makes sense, but the scores are really statistically significant. We also showed you got to probably address this capsular area. Chris Dewey, myself, many others did this here with me. And it was a really good overall study to show us we probably have some level of capsular dilation, because that capsule in the back is just not that great. So here's a classic chem lesion. You can see the crack here and how we're going to go about fixing this. And here's a classic flap tear. And these flaps don't really, sorry, these flaps don't have posterior cracks in anteriorly. They don't have cracks anteriorly. You don't have bucket tears. These are all posterior. So there's more flaps, more cracks, and more buckets posteriorly. More flaps, cracks, and buckets posteriorly. Completely different. And Brett has been a master at this, looking at glenoid dysplasia. A lot of times you can see a subtle fracture posteriorly here and you have to be able to address that as well. And if you see a fracture early, or you get a hint of a demon in the back and it's an athlete, fix it early. Because these are hard to address once you get posterior aversion, as Brett talked about. And that's probably some level of acquired stuff. And this is what I'm looking for, not just the capsular laxity on the right, but also the classic posterior labrum tear. These are all gadolinium, but with a good three tesla magnet, you can find this out pretty well. Bone loss, it's a problem. And it's much, much different than anterior bone loss. Just like the physical presentation, this is something else you have to address surgically. The front bone loss is off a cliff, about 90 degrees. We've shown it to be about 40 degree angle out the back, if you have bone loss in the back. And that's on average of a lot of posterior patients. And then this is where we're gonna try to decide, should we fix this? Well, Justin did a great paper and found that if you had bone loss, 15%, like we're looking at this just anteriorly as well, 25 times higher failure rate if you had bone loss posteriorly. So bone loss posterior is bad, maybe even worse than anterior, believe it or not. And so here's some of the controls and normals and what posterior instability looks like. You can see some of the tears, the patchless capsule. And this is what we're gonna address. The other thing you wanna address is if you have some attritional bone loss. And if you have this bone loss posteriorly, sometimes you have an attritional fragment. You have to manage that. And you also be able to need to know where that is and where you're addressing it surgically. And we've shown that this is probably much different. Decker did this with me, he's at the Air Force Academy now. And my partner, Peter Millage and Bradley, we looked at about 71 patients. And the mean location of the defect was different than anteriorly if you were to flip it in a mirror image. So it's a little bit higher. It's kind of in, if you look at it, it's almost parallel where the shoulder's gonna come out in line with the acromion. So you see how the shoulder's gonna clear the acromion, come out just parallel at that position at rate, we'll call it right around seven o'clock. So you're gonna keep that in mind. It's right around seven o'clock. You're looking at how these present. Again, you have the middle part and the upper part of the big problem. This is where you have to be able to fix it. And then we're gonna start going through these algorithms. This is something that we printed on and some many authors on the panel with me here. We looked at posterior instability and how we're gonna fix this overall. But basically the workhorse, this is what we did back in the late 90s and 2000s with one of my mentors, Tim Malone, who just recently retired in practice. But this is what we did. Look at these knots. You probably many people and younger folks in the audience probably haven't even seen these things, but knot discipline and how to tie this was a super key and how we did all this. And now we've really gone knotless. And so that's what I really like to do, which is better way to restore it. We've shown a really nice way to do that. You don't have any knot issues. And then we're also looking at bone loss reconstructions. And we'll talk about that later, but really gonna just focus on the arthroscopic where you can really focus on the additional pathology, Hagels, capsule tears, all the things that Brett showed really nicely. The return to function is really high if you do it well and get the anchors in the right place and placate the right amount of capsule. And if you address all the pathology that's there. We looked a little bit at patient position. I'm not sure it matters 100% posteriorly, at least for me and how I do things. And I know a lot of others lateral is pretty easy to be able to go posteriorly, inferiorly, superiorly, kind of around the world. But if you, whatever works well in your hands, I think is okay because it's also been shown by Brett Owens and John Dickens and others that it's overall probably doesn't matter. So portal placement, general, and this is a lateral decubitus, the posterior portal is in line with the lateral edge of the acromion, we have a posterior lateral portal, and then usually I just use a mid-glenoid portal, I don't use that second one right there, I just do the mid-glenoid which is just lateral to the coracoid. So basically three portals to do this whole case. Here's the long head of the biceps to the right, we're going to come in very low and very flat up, right above the middle glenohumeral ligament, wherever that spinal needle is, and be able to do the case. But the key is this posterior lateral portal, and so here's a, this is actually an anterior tear but I'm demonstrating so it's an alpsa tear, but it does extend around the back, it's got some cracks, but we're going to start in the back and just do this just like we would an anterior tear, but all of my anterior repairs start from the back, and so it's a very similar type of procedure, you have to be able to go around the world and address all the, and address all the pathology. And then this is the key move, and this is, helps me with anterior, inferior, multidirectional, but really posterior, is that posterior lateral portal, I'll show it on the next video, but it's basically just four centimeters right off the back edge of the acromion. So posterior lateral edge of the acromion, just go four centimeters direct lateral, there it is here, and show the spinal needle, I'm gonna be right about there, probably just miss this person's tattoo right on the edge of it, but it's just four centimeters lateral, and that spinal needle comes in, there's kits that you can use now percutaneously to be able to get in, a couple companies have different dilation kits that you can use, there's a bunch of companies out there that have these, and that allows you to get in. So here's a classic posterior tear, you don't see this pathology anteriorly, this is classic, you get in there and you start seeing some flaps posteriorly in a shoulder you're scoping, and in the shoulder and you see these things, you know you've got a posterior labral tear and you got to address it. So this is that posterior inferior tear, we're gonna start addressing it, we're gonna prepare the labrum using a combination of a shaver, I like using a very small, like 3.5 millimeter shaver, and we've written this technique up, but just doing everything from the front is key, it's really much easier, you see we're coming to that mid glenoid portal, if I'm critiquing myself here, I'd want that instrument even flatter to the glenoid, so even if I can get that flatter and come in posteriorly, and so now we're getting rid of the flaps, we're trying to get this, you can see it's a pretty extensive tear, but the predominant symptoms in this patient were posterior, as Brett Owens has nicely demonstrated in terms of how we have to separate this out. Now I'm bringing in the posterolateral portal for the anchor placement, you can see I can get really nicely anywhere, this is a 16 gauge spinal needle in some of these kits, so it's a little bit more robust, and then you're able to change it up to some nitinol dilation, which is the absolute key here and makes your life a million times easier, we're then able to change that over and put in a variety of anchor guides, and put all the anchors exactly where we need, and then put our anchors in, there's a much clearer view of it, so this is the posterior portal, this is the classic lateral portal, it's much different than a beach chair portal, I do both, beach and lateral, I personally think it's important to do both, well there's the classic anterior portal, just mid glenoid, just right off the coracoid, just lateral, I don't use the high glenoid one, that's the one right there I'm showing, I don't generally use that one in posterior, I really don't need it, that's one I use anteriorly, and then we come into the diagnostic arthroscopy, you can see this patient, look we got again, a flap, more frame, more cracks, more bucket handle tears, you see that, it's posterior instability, and you may have missed it, I know I've missed it in the past, and we've gotten much better at it, and so here's the anterior superior portal, we're gonna put that in, this is actually a switching stick, there's a handle here which can facilitate putting this in, and we're able to dilate this, put the switching stick in, so you're just really nice and gentle with the capsule, and then once the switching sticks are in, I always switch it up to the metal dilator, and then we'll put the cannula in, and as soon as I get that switching stick in, I don't use the sharp end anymore, I want to try to preserve the cartilage, and then you can use a variety of different cannulas, I also like a variety of elevator sets, this is one that I use that helps just prepare the back, this has actually been helpful because these were specific for kind of prepping up posterior tears, there's a lot of different instruments and tools you can change up here, but this, there's a lot of different companies that have stuff, but this one for me has helped because it's actually been really good to augment the preparation of posterior tears, it really makes it kind of easy, I spend about half my time preparing, and half my time fixing, and so you can see we're going to come in, we're going to come in, do this prep again, get this posterior labrum all set up, and then hooks from the back are key, and you want to have the right hook so that you can use this properly, there's a lot of variety of hooks out there you can use, we're just basically going to come in from the back, and feed the suture in, here's our anchor, a knotless type of construct, and what I'm trying to do here is tease out how much I want to take, I've looked at the MRI, I've looked at how much gaugé test they had, as Brett Owens nicely stated, and here I'm taking about maybe five, six millimeters, this is not the most hyperlaxed patient, we're going to feed this through, the key with the hooks are you always going to poke the capsule perpendicularly, and then feed it through and under the labrum, and then pass this all through. So when you look at a lot of Justin's work here, out of Pittsburgh, and Jim Bradley, and Justin was our fellow in Vail, we did a lot of this work as well, you can see overall really good return to sports and player satisfaction, and the arthroscopic repair really is the way to go, even in some of these challenging cases, I know we're going to get to some of these in a second, so I love the arthroscopic approach for this, it does very well with good techniques and a lot of knotless anchors. Thank you. Thank you, Dr. Provencher, and Dr. Owens, it's quite the body of work, you guys have taught us so much, and great, great start here. All right, we're going to have Nick come up here, he's filling in for Brian Waterman, as I mentioned, Brian had an issue with flights this morning, so he's going to do his best interpretation here, and I think he'll do a great job of basically looking at the throwers in this cohort. Thanks everybody. Yeah, Brian sends his apologies, his flight got canceled last night, so he won't be here until later today. I've seen him give this talk before, so I'll do my best to give it on his behalf, I'm his junior partner at Wake Forest. These are his disclosures, I personally don't have any disclosures. In talking about posterior instability in throwers, it's important to also incorporate the concepts around the slap lesion. Many people talk about this as an American disease, potentially from overexposure, or over diagnosis, or even over treatment, and we'll talk about later how these may not even be pathologic in many cases. He likes to talk about the posterior labral tear being the dark side of the moon, with recognition becoming more recent, and exploration becoming more recent than the anterior labral pathology. Historically, we talked about posterior labral tears with electrocution, seizures, hyperlaxity, and less commonly, athletic participation, but we've had increasing recognition of posterior labral pathology, with battered shoulder, contact injuries, and certainly with weight lifting as well. Battered shoulder or posterior instability caused by a swing is something that we've become better at recognizing. This occurs in the lead or front shoulder, where the shoulder is adducted, often reaching for a low and away pitch, and usually it's a swing and a miss with a traumatic event, but it can also be repetitive microtrauma over time. Shoulder instability on the posterior side is often more than just that 90 degrees of the posterior inferior labrum. We often see it with slaps as well, with extension posteriorly. We see 270 degree or 180 degree tears commonly, and extension from anterior tears to posterior tears, even with anterior instability, as was previously discussed. The type VIII slap tear, which is that slap tear that extends posteriorly, and you can see a video here at the bottom of a repair with an anchor posterior to the bicep. This is something that we always need to be aware of, and these may be slaps that require more surgical management, and may be less of the adaptive throwing slap that we see to be not pathologic or not clinically significant. There's some debate about whether the slap tear leads to the posterior labral tear, or whether the posterior labral tear can extend up around the back. The pathophysiology of the slap tear, I think, has been well described already, in terms of several different mechanisms, whether from biceps traction or abduction external rotation with the peelback mechanism, and that can certainly intuitively extend into a posterior lesion as well, but you can imagine a posterior lesion initiating and extending superiorly in the reverse, especially if it's not the throwing shoulder. There is some adaptive change in the thrower that contributes to increased load on the posterior labrum. There's the pathologic peelback mechanism, as I mentioned. Throwers can have glenohumeral internal rotation deficits or total motion arc deficits with excessive external rotation, capsular contractures that are asymmetric, and then certainly losses of posterior cuff or scapular stabilizers, scapular dyskinesis, or kinetic chain abnormalities can contribute as well. Clinical evaluation, I'll kind of breeze through this, because it was previously discussed by Dr. Owens, but I always want to look for hyperlaxity, sulcus sign, hyperabduction test, as was previously discussed, and then the load shift being certainly the mainstay, especially under anesthesia. Kim and jerk tests have been helpful in posterior instability to elucidate pain or clicking symptoms in the back. Biceps testing is also relevant, as these are often involved with superior labral pathology or slap lesions, too. And combination of tests is really the best way to elicit a more specific exam, as these tests can be sensitive but not specific. Scapular mechanics, as was discussed, is critical to examine in all of these patients. And evaluating scapular dyskinesis should be a part of every shoulder examination, particularly when there's a question of posterior instability or throwing-related posterior shoulder pain, or anterior shoulder pain, for that matter. We did look in our pitching lab at scapular dyskinesis in pitching. We saw patients with increased scapular internal rotation or protraction and decreased shoulder rotation velocity as a result. So where slap pathology or slap adaptation, rather, might be an adaptive change or an advantage for the thrower, there's no competitive advantage to scapular dyskinesis. So if that's recognized, that is not an adaptive change that's helpful to the athlete. Scapular thoracic abnormalities can be managed nonoperatively in many cases with dedicated therapy programs, but it often requires referral to a throwing center or somewhere that does have experience in managing these problems, because a typical program won't always correct these issues. There's been terminology in the literature of clinically significant labral pathology in throwers versus adaptation or clinically insignificant labral pathology, and it can be a continuum there. But certainly, we want to evaluate for the tension on the capsular ligaments and understand what normal adaptations can be seen, both with MRI and with the scope. So certainly, the Buford complex and labral foramen is common, but also superior labral instability or increased motion may be an adaptive change in these throwers. There have been studies that looked at adaptive bony changes in throwers as well, particularly those who had high volume of throwing in adolescence, and you may see glenoid abnormalities, as was discussed by Dr. Owens, in throwers that occur during development, whether that's with hyperplastic posterior labrum and hypoplastic posterior bone or overall retroversion. One study found 60% of pitchers had retroversion of the glenoid that was above what normal ranges would be. This study out of Japan looked at that as well, and you can see that adaptive change in the left-sided X-ray with the circle in someone who's a thrower compared to their non-throwing shoulder. Another thing to keep in mind with posterior pathology in throwers is the Bennett lesion or the exostosis involving the posterior aspect of the capsule labral complex. This is often involving the posterior band of the inferior lateral humeral ligament, but it can be seen in other areas around the posterior aspect of the shoulder. And these aren't always symptomatic, but they do often portend additional pathology, such as superior labral tears, posterior labral tears, or glenoid cartilage lesions. We talked about the Kim lesion briefly, or that incomplete concealed crack in the posterior labrum, and that's something to always be aware of. It may be harder to recognize on a non-contrast MRI, but you can see more aggressive tears in ones that mirror some of the pathology we see anteriorly, such as with associated cartilage defects, associated periosteal sleeves, or bone loss. There is the idea that this is a shared load in the anterior and the posterior aspect, and I think we should apply some of these concepts to the posterior as well. So when you have an anterior dislocation, you get posterior capsular stretch and that Bankart lesion, and you do see the inverse as well with posterior instability. Surgical management of posterior labral pathology and throwers has to be somewhat conservative to reduce the chance of over-constraint, which can impact their performance. Limited debridement is always an option and can be considered when the labrum is not unstable. There's pain symptoms without provocative instability, and some of those flaps or frayed areas instead of frank detachment of the labrum. Repair at our institution, we typically perform in the lateral position. It's helpful to have additional bumps underneath the axilla, which both push the scapula down and give a counterforce to that armpit lateral traction, which can really give you good distraction and great visualization of the inferior labrum. We liberally use the 7 o'clock portal to access the posterior inferior labrum, and at times the transcapularis portal as well. Here's an example of a spinal needle going in through that 7 o'clock portal, which gives you a great trajectory for anchor placement. It's a very safe portal if placed percutaneously in the correct trajectory and dilated appropriately. You can really get access for suture hook placement. You can get access for anchor placement without skiving, and you can really also get down to that 6 o'clock position, which is so critical in instability. We've gone to using knotless anchors with retentioning in many cases, both for the effects on preventing knot stability issues or knot migration issues, which I'll show in a subsequent slide, but also due to their ease of passage and preventing having to tie from that 7 o'clock portal, which can just be a cumbersome extra step. One thing I'll mention is that, and I wanted to mention on that slide, sorry, one thing I'll mention is that just like with fractures, this is an open reduction and internal fixation, so just putting in the anchors without appropriately elevating and reducing the labrum is not effective enough. So we emphasize appropriate elevation and mobilization of the labral tear, and then using a grasper to reduce the labrum onto the rim before securing that anchor. So reducing and fixing rather than just fixing in situ. Additional things that can be considered, particularly in patients who are hyperlaxed, are imbrication or closure of that posterior portal, particularly if you make a larger portal with a bigger cannula in the back. Creating an additional capsular tear in someone who has capsular laxity or insufficiency in the posterior aspect of the shoulder may contribute to further instability, and so we'll use an absorbable suture to repair our posterior portal in those cases. And again, the advantages of knotless fixation, which has become more common, helps to avoid knot migration, knot security issues, as well as that abrasion or hemeral head contact problem. Many of us, I think on this panel, have gone to knotless fixation. Certainly the historic standard of tying knots still applies if done appropriately. In our contemporary labral repair, we again use knotless fixation. We use either simpler mattress sutures, depending on how much additional advancement or reduction of labrum is required, limited suture contact with the cartilage surfaces, and retensioning to allow consistent tension. One of the main disadvantages of a knotted anchor is once you tie that knot, that's the tension you'll have. But often, as you continue to advance the labrum, retensioning the previous anchors is fairly helpful in restoring a consistent tension across each point of fixation. Postoperative rehabilitation for posterior labral pathology should be modified compared to your typical anterior protocol. The position of instability and load is different, and so make sure that your physical therapists have a protocol from you that emphasizes the differences in labral repair from posterior and anterior. Outcomes from posterior instability have really been quite good in the literature, and there are several series that this slide emphasizes two of them. Excellent return to sport, 90% to 94%, but some series have shown the same level of participation can be as low as 61%. So it's important to understand and counsel patients that we can definitely make you better, make your pain better, we can get you back to sport, but there is a risk of decreased performance, and some of that risk is technique-based for us. So we want to be careful of where we're tensioning the capsule, being mindful of the adaptive changes in throwing shoulder, and being cognizant that if we over-tighten someone's labrum in the superior aspect, or especially if we place anterior superior anchors, we could be affecting their career. Dr. Waterman has performed some of this research in the military population, which again showed relatively positive outcomes with low failure rates overall, but that's not directly applied to the throwers. Risk factors for failure, that's previously discussed a bit by Dr. Owens and by Dr. Preventer as well. Retroversion of the glenoid, glenoid bone loss may be as low as 13.5, but it's certainly at 15. So his indications, and I share a lot of this methodology as well, being his practice partner, but traumatic instability, provocative instability, low glenoid bone loss and retroversion, great indications for soft tissue stabilization in the post to your shoulder, more patient counseling and shared decision-making in the throwers, atraumatic or insidious events, borderline glenoid bone loss or hypoplasia, some retroversion and dyskinesis, which may warrant preoperative physical therapy. And then certainly some caution should be warranted with increased glenoid bone loss, dysplasia, global retroversion of the glenoid and glenohumerosteoarthritis. So in conclusion, incidental or post, incidental posterior labral pathology, either atraumatic or with repetitive overuse and microtrauma can be pretty common, and it's important for us to recognize that pathology and shoulder pain and not to just assume it's the internal impingement and cuff-related problems. Traumatic posterior instability is often combined with other labral pathology, and so it's important to understand that as well. Posterior stabilization is very successful, it has low rates of recurrence of pain and instability, but it may reduce return to sport if it's not done carefully. And then risk factors for failure, again, bone loss, glenoid retroversion, and hyperlaxity. Thank you. Great job, Nick, filling in. You're just as good as your colleague. Hopefully that's not recorded. Great job. Yeah, I think just like you mentioned and Dr. Burventure mentioned, it's so important you see some of these young people that are diagnosed with impingement, and some of those people probably really have posterior instability and slab tear, definitely not impingement. So we're going to move on to our illustrious director of this great conference, Dr. Dickens, Professor Dickens. He's going to talk about dealing with bone loss and posterior instability, which is certainly a hot topic. Looking forward to it. Thank you. Awesome. Well, thank you, Justin, for everything, and I'm excited to get the meeting off to a start here. So let's see. Is it? All right, so disclosures are in our app, so just a one-click plug if you haven't already done so, use the Engagefully app. So I think I'll start off by saying I learned a lot from this group here in terms of posterior instability. One of the things that, and I think Brett is right, is posterior instability, while it's not new, I think we are just seeing it, and possibly with kind of a change in how we're recognizing it, we're seeing it more and more. And so as we're starting to see it, we're starting to learn more and more about it. And so I just wanted to start with that, and I think one of the first things is when we see these folks, how is the nonoperative treatment sort of progressing with these folks, especially in the young athletes and the military being a part of that? We know that the nonoperative treatment in this group, and especially in a push-up population, is not necessarily successful. It's not as significant as the young anterior instability, but 48%, 50% almost are not successful with nonoperative treatments after about two years. If you follow those patients up in a civilian group, 10 years, 70% have had surgery. You know, this group and Matt and Brett and others, Dr. Bradley, have shown that regardless and probably even unrecognized instability in some of these earlier studies, arthroscopic labral repair is certainly the gold standard and we're not trying to kind of debate that. No question that that is a very successful surgery. But if we look in this non-operative group, we do know that at follow-up, and this is a series that we looked at relatively recently, we look at those failures, we see that failure of non-operative treatment is associated with progressive bone loss. Now, it's not dramatic in this retrospective study, so this is just looking at the time of initial presentation with posterior labral tear or posterior instability, about 2.5%, and that number increases about 4% over the course of a year and a half in those folks that have failed non-operative treatment and had repeat imaging. So maybe not an ideal study, but credit to Brett, and he had a large prospectively followed group at West Point, and these cadets, when they came in, were MRI'd at baseline, over 1,400 shoulders, and then followed in that environment. We had the opportunity to look at those folks, small numbers that had posterior instability, but if you look at those that had a single instability event posteriorly, they had 5% bone loss. You can see those measurements here in the top row, and then you had a group of those folks that had multiple recurrent instability events, and that's where you started to see some bony loss that was more significant, 16%, and you can appreciate that here in the bottom. All right, looking at a series of posterior labral repairs, and this is recurrent, repetitive posterior subluxation patients. The vast majority of these patients, when we look at posterior bone loss, probably don't have bone loss, so that 0%, not really measurable, but a number of patients, 50% have what I would describe as measurable bone loss. That's bone loss that is beyond 0% in the 2%, and then a smaller percentage of 13.5% in this group all had posterior labral repair in this population. So this was just when we were first starting to identify posterior bone loss, and this is, as Matt pointed out, the anatomy of posterior bone loss is distinct from anterior instability. At the top, you can see that posterior bone loss is more posterior and inferior. It's more oblique, as opposed to anterior bone loss, which is more perpendicular and anterior. You can also see in the bottom that it's more sloped, and we'll show that in some separate videos, but this is, as distinct from anterior bone loss, which is perpendicular to the glenoid, this is sloped, and it's inferior and oblique. So this is what Matt was showing earlier, and you can start to see that the slope of bone loss, over 40%, is certainly reaching a critical range, and that oftentimes goes hand-in-hand with glenoid retroversion, and then hand-in-hand with glenoid dysplasia. We talked a little bit about the acromion, and this is Gerber's paper that he, when he was comparing some differences in the acromion between anterior and posterior patients, you can see on the right-hand side there, a Latter Jay patient, and you can appreciate the oblique acromion. It has more coverage of the glenoid. It comes down more inferiorly, and on the left, a posterior instability patient, less acromial coverage, that is not coming down as far on the glenoid. It's higher, and it's flatter. So certainly, possibly a setup for instability, and you might ask, well, okay, great. It's non-modifiable risk factor. What are you gonna do? But I do think that there are some correlations that are important for at least considering how we might manage these, and maybe, as our algorithm evolves in terms of posterior bone blocks, how we might think about that. So we certainly, in our series, have looked at this in a series of different cohorts. We know that high, flat acromions are associated with failure of non-operative treatments. We know that they're associated with failure of arthroscopic label repairs, and we know they're associated with posterior glenoid bone loss. So currently, the indications for posterior bone loss, as I mentioned, they're evolving, and there's still much to be learned here, but this is, for me, in my hands, it's a revision posterior instability patient, and posterior glenoid bone loss in 20% is absolutely a bone block case. Revision posterior instability in the subcritical range, I would certainly be considering this over a revision arthroscopic procedures. This is not my go-to procedure for MDI or for primary instability treatment for many of these patients. How can we address this? Well, osteotomy is certainly an option, but we know that in the limited hands, and these are expert surgeons that have really done this, it's associated with high recurrences, glenoid fracture in over a third of patients in some series, high recurrence rates in some series, even after this procedure. So maybe less desirable. There's a number of different free bone block procedures. It can come from the scapular spine, as Brad mentioned, iliac crest, distal clavicle, and distal tibia, and there's a number of different advantages and disadvantages to these. The distal tibia certainly has articular congruity and cartilage, and I do believe that conveys some inherent stability when you match the articular cartilage and the congruity to the native glenoid. And the cost as well is certainly evolving as a problem, and perhaps frozen versus fresh grafts might be a little bit more cost sustainable. So I'll just kind of go through a little bit of the technique. I do think that a 3D model for these is helpful to really understand the anatomy of the posterior glenoid because a key portion for this is making a perpendicular flush glenoid cut. So this starts with preparing the graft, and again, this is a distal tibia. There's a number of different graft prep capabilities. You don't have to use a graft prep station, but I use this guide, which comes from a distal tibia set, and then I pre-drill and then pre-cut my graft. The majority of these are about 10 millimeters. I don't think in many of these that they need to be much larger. You can see the congruity there of the graft. 10 millimeters in the other most common size for me is actually less than that, so between seven and 10 millimeters. And then we pulse flush and then use PRP or whole blood. In terms of the arthroscopy portals, I think this is similar. So I have done both beach chair and lateral for me. I feel like doing this in the lateral position is very helpful. These are the positions. So I think for this portal, as was mentioned, this is high and outside, and I actually feel like this posterior portal being extra high and extra outside is really critical for this because this becomes your working portal and you need to be able to move inferiorly along the glenoid neck for the preparation. Then we have our glenoid delivery. So this is more medial probably than it even appears here, and this is in line with the glenoid articular surface and inferior, that's our graft delivery portal. And then certainly you have your posterior lateral accessory portal as was described by Matt, and this is for repairing our capsule. So with that, you can see this is the left shoulder. And we're viewing from anterior. We're working in that high and outside position, just removing prior anchors. I think here you can really appreciate the sloped glenoid. So all that kind of articular cartilage that's been worn away and the labrum that's more lateral to that, that's that kind of sloped bone loss that we're starting to see. So we're starting to elevate that and you can really see it here, prior anchors as well. And this is where I think visualization with a 3D model is helpful because we're taking this down to create a flush surface. This is the vast majority of this case is spent on this and it's hard to get in parallax some of the ensuring that you have a nice flush bed here for your native glenoid bone block. But once you have measured and you have your adequate depth and length, so generally speaking, these are 20 millimeters from inferior to superior and you have your depth, which is just above 10 millimeters. For me, we can create this posterior glenoid. This helps me deliver the graph. So I go medial to the capsule in the labrum. I have a traction suture and then I use this. This comes in, this has a little lip and I can place our pre-drilled holes in the nubs of the distal tibia graph delivery here. And then we can measure, place our K wires and then our cannulated screws here. Contrary to anterior bone blocks where these can require accessory portals, I actually feel that posterior screw placement is probably easier than using a suspensory type fixation. And again, you can see, I think the key portion here being the articular congruity. And if we get to it, I can show you some other cases, but I think that really taking your time there really helps to make sure that you have a good articular cartilage congruity. And then you can use the traction sutures that you've had and you can place your anchors if you wanna do a labral repair above that. And generally, I have done that just because many of these cases have had recurrent posterior subluxation and failed repairs. So I worry about the capsular volume and laxity that persists at baseline as well. Regardless, I still think that there's a lot of skepticism and maybe rightfully so for these outcomes. There's not a great series that looks at these, particularly with arthroscopic and particularly with distal tibias. But overall in the larger series, there's still recurrent instabilities. So between 10 and 12% and there's still revision surgery. So about 120%, so not an insignificant number. And more recently, there was a systematic review, again, all comers, and certainly there's some selection bias with many of these revision cases and distal tibia or bone block cases having more complex surgeries. But the take-home point here was the current instability in the systematic review all the way up to 63% revision surgery, almost up to three quarters and row scores between 60 and 90. The take-home point from this systematic review is caution when proceeding with the distal tibia. So I think that's where we stand now, but I do think that in the right patient with the right selection criteria, I do think this can be an excellent procedure. This is that case I was showing you earlier and this is a follow-up on CT scans. So we're starting to see some of that bony healing and progression back to return to duty. So in summary, I think posterior glenoid bone loss is present probably, we're recognizing it more. And posterior bone blocks, while potentially there's some concerning findings, I think do offer a great advantage or a great solution for some of these more complex posterior bone loss and revision posterior instability patients. Thank you. Thank you, John. If anyone has any questions, feel free to stand up or raise their hand and ask along here. One thing, John, just to follow up with that, this is not a super common surgery in something, early career surgeons like myself and others in the room are a little weary probably to undertake. Are your thoughts arthroscopically? Do you think it's actually easier? Tell us what you think if you start off. Is it easier to do it open your first couple cases or scopes better visualization? I mean, I think it depends a little bit on your background. So I personally feel like you get a better look at the glenoid and you have a better look arthroscopically at the reduction. You're not looking at a big deep hole and a lot of these patients have large deltoids. So I think arthroscopically, actually the only step that's different is just preparing the glenoid and taking your time to make a flush glenoid. Cut everything else is very similar akin to anterior distal tibias or other open options. So it's really just kind of the delivery of the graft after that. So I think if you've done an arthroscopic anterior, the graft delivery is easier. So it's really just preparing the glenoid posteriorly. I think for me, it was an easier approach. I would definitely do it in the lab ahead of time just to get comfortable with that. But I think for me, it's a little bit easier arthroscopically. Can you give us some tips about preparing that bone, the angle and everything? I would just say that not to be scared of the open too. So John's a better surgeon than I am. And I've been scared of doing them arthroscopically. I think I also just don't, not doing it very often, right? I mean, you start getting slick and doing 10 of these a year, I guess. I just don't be scared to do it open. I do, I want to get it right. I want to get my screws right. I want to get it flush. So first couple of weeks, I took the deltoid down. I took the whole posterior cuff down and you want to be able to see it. So I think, just don't be scared to do it right and do it open if you're concerned. Can you tell us some tricks you and Dr. Preventer, kind of the open technique, how you guys like to do that? And Dr. Preventer, have you transitioned more to scope or open? You kind of were doing both when I was a fellow with you. Yeah, I mean, I fully echo what Brett Owens says here. I started this all open. We knew open anterior. We knew how to fit. We knew that, at least for the distal tibia, it was a workhorse. We started this really at crest, to be honest, before we helped kind of come out of the tibia. But the tibia now is workhorse, like John's shown very nicely. And many people adopted, including you guys now in Pittsburgh and many others. But the open is great. And to Brett's point, you got to split the deltoid. There's a classic approach back there. It's a board's question. Terry's minor infraspinatus interval. You can go through there. But the trajectory is tricky. It's a deep, deep, dark hole. And even if you're open, it's a deep, deep, dark hole. So I quickly got to arthroscopically assisted and then all arthroscopic, because for me, it was just easy. It was like doing a rotator cuff. Rotator cuff open's fantastic, but at the end of the day, it's a long day. I can do it arthroscopically way better at cuff. And now it's just a little bit of learning. It's not that bad, actually. So do open, arthroscopically assisted, and in a couple cases, you got it down. Can you tell us a little bit about the tricks from the open standpoint, how to prepare the posterior glenoid and then also arthroscopically, that angle? It seems like that could be a little bit tricky to get the right angle, to get that hole width, the appropriate depth. Yeah, I think, first off, I think from a arthroscopic approach, number one thing that you should do is just make sure that you have that high lateral posterior approach, because that gives you your trajectory to visualize and then subsequently prepare the posterior glenoid. And then the next hard part is delivering the graft, like we were speaking about. And I think from an open standpoint, it's hard to get the trajectory, at least for me, kind of perpendicular, parallel to the glenoid with the screws and in a deeper kind of hole. So for the kind of mini open, little percutaneous graft delivery, that's well medial. And I actually kind of localized that with the spinal needle. I didn't show that, but I localized that with the spinal needle before delivering it. So you're viewing from, for me, my anterior superior portal, which is where I'm visualizing when I'm doing posterior work and then creating a very kind of posterior medial spinal needle trajectory that's in line with the glenoid and even just kind of slightly medial to that, because that's going to be your trajectory for your delivery and your graft. And then once you're in, you can use the... In this case, it's just a... The graft is on a graft delivery kind of instrument that's kind of secured with a... I use OPDS suture for that, which just helps keep it on there. And then you can make sure that that's flush with your glenoid. And once that's in, you can put your cannulated K wires and then drill over top of that. So for me, that's the ideal kind of preparation for that. But I think the other part is the other area, and this is why I use... I like to kind of really preoperatively plan for these. So getting your depth, so from anterior to superior prepared, so you know how much you're taking from anterior to superior, and then also from medial to lateral, so you know the depth of where, of how much that bone block is gonna be sitting. Right? It looked like you went underneath the labrum. Exactly, yeah. So that helps keep it medial for that exact reason. So I use that traction stitch to keep it lateral and then just come medial to the capsule in the labrum. And that's for that point, exactly. I put a traction stitch in the labrum and I just pull it out. And just pull it out, it seems easier. Just have a few go away. It really is pretty tight, unless you're trying to separate it. Look, if it's a ball, I mean, you really don't have a chance to connect the medial terminals with the lateral one. So, it's a nice circle. The other key is you make your graph really small, too. When you start this, you want your graph to, your graph's big, but you go, oh, I'm missing a bone, I gotta put this big thing in, and it's really hard to manage, it's hard to manipulate, so you have a nice, small, slick graph that I think facilitates the passage. And you don't need much. Yeah, I don't know. I feel like the error for me, any time, when doing, especially at distal tibia, is to put too much bone there, because you worry a little bit about graft resorption more, and I don't know that we know the answer for that posteriorly, but certainly anteriorly. And so, I think the bone, it doesn't take that much bone to get subcritical or critical bone loss. And so, if you're putting in a 10 millimeter bone block, that's pretty substantial bone loss do we really need that much. And if even just a couple millimeters smaller makes a big difference. Yeah, totally. It's five, six, seven millimeters is massive back there. It doesn't need much, and maybe 22, 23, top to bottom, that's a lot. And if you look at what we looked at the defects, and Justin helped to tell me this study, they're about that size, that's probably even too big. The other thing that's helped is 3D printing to help us understand it, and if there's a way you can get a 3D printout of it and potentially sterilize it, have it on the back table, almost like we do shoulder arthroplasty. I get one, I almost try to trick, don't tell I said this, try to trick the company, give me a 3D printout somehow, get it sterilized, and I got it on the back table, and I can do some bone wax, I can do some cement, it's pretty cool stuff to have that 3D printout on the back table. I can perfectly put on the graph, the tibia, and shape it. We have a debate this afternoon, Tokish, BD, no. It's 100% screws, and look, I will buy votes. Screws are way better, okay? I was gonna tell you, wait. No, actually, I think we're evolving on the sutures. The problem with the suture is there's medial displacement, and it's the shift. Compression's okay, we found, and even our studies, when we tensioned it to about 80 newtons, it did pretty well, but after, there was still the shear, which is the medial lateral translation of the graft, and I haven't long, others have shown less healing now with CT scan than buttons. I think we're getting close, but we're not quite there. Screws are the best. One thing, as you taught us, Dr. Bruncher, about that sloping and off-axis, tell us about where you guys position this bone block. Do you try to get a little bit lower and be off-axis a little bit, rather than just perpendicular? John or Brett? Just when you're putting your bone block, the angle you're placing it. Yeah, I think, so, that's where the templating piece is really helpful, because I do try to put the inferior aspect of the graft at the inferior aspect of the glenoid. So, what that means is you're probably, as you're preparing your glenoid recipient surface, you're probably taking more bone, approximately, so it sits flush. So, I do try to get it posterior. Now, I don't think it needs to be absolutely at the six o'clock position, but I do put it as far inferior as I can get it. Makes sense. I got a quick question, since we have an expert in the room here, Dr. George Davies. How successful are you in rehab of posterior? Let's, it's an athlete that needs it. Blocking linemen, pressing, bench, incline, push-ups, military, your background. Tell us your tips and tricks and how we can optimize this without surgery. As far as the bench, when I do the push-ups, bench pressing, things like that, obviously a wider grip, that way it anchors the humeral head to the glenoid. But the most important thing I do is what's called a reverse contrecoup concept. If we have an anterior instability of the shoulder, think about it, what provides a dynamic stability of that? What's your posterior cuff? Likewise, if somebody has posterior instability, we focus on a contrecoup concept of dynamic stability, of focusing on trying to create a new lateral ratio and having the internal rotators stronger than the external rotators, which they are anyhow, too, but we would try to bias that relationship even more. So by different positioning of the shoulder in different activities, you saw about 48% repair rate anyhow, but nevertheless, by positioning things in rehab, by creating a contrecoup concept of changing the dynamic stability is the things that we would try to do. So those would be a couple of tips. But I do have a question, I've been having a burning thing, I asked Dr. Dickens a year ago, we have a patient who has a posterior disability, they have a reverse pill sacs, it's pretty significant. Do you all do like a reverse REM massage, like a rockling technique to stabilize that? What do you do with that? Yes, I mean, I wouldn't do, it basically is the reverse REM massage, with the subscapular defect, and not necessarily like a McLaughlin, where you're actually transferring the lesser, but it's pretty easy to do, it really is. It is big enough, and certainly you can graft it, and I know we have a case potentially on that as well. John, you want to? Is that going to compromise when you do that reverse, is that going to compromise the subscap and the act of stabilization? Well, as you mentioned, yeah, being that contra-coup concept, the subscap is an extremely important stabilizer, but I have to look and see. I don't know that there's been enough reported that have done post-reverse REM massage strength testing, so it's an open area. While we have you, George, I'd love to, I would like to share with the group, too, and hear your comments on it. I've had some success recently with a shoulder pacemaker for this problem. I've had two failures that have been stable to my objective exam, and have had some, still able to pop it out the back, and still have symptomatic instability, and I've had great success with a shoulder pacemaker described by Baroda. I don't know if anyone else has used that for posteriors. It really, it's just something to think about. It basically is a biofeedback type, well, it's basically a STEM unit that has coordinated activity of the muscles, and can provide a coordinated response to activation, so I don't know if anyone's had experience with that. I mean, I think, broadly, I think the physical therapy, the rehab, is more important for posterior instability than the anterior instability, and we were kind of chatting before. I think these patients are more likely to have dyskinesia than anterior instability patients, and so I think they're, it's almost like they're teetering on the border of developing scapular dyskinesia just by having posterior instability, and then you add in a couple more variables. Maybe there's some laxity there, or other factors, and they're, all of a sudden, have two problems of posterior instability as well as scapular dyskinesia, and sometimes they go hand-in-hand, so I think, I have limited experience with it, but I think it's a great use for posterior instability. I couldn't agree more. I tried a couple patients with it. I've been moderately successful, and I probably was pushing the envelope in some bad gage, bad multidirectional, which is really how Philip Moroder kind of described the initial thing, was for bad multidirectionals, but look, anything we can do to get the muscles better and work a lot with therapy and posterior, massively important. The unit's cost, the unit's cost is $3,000. It's $3,000 for the unit, and it's not just the unit, too. You have to have a, we have one therapist at, of our eight or nine centers. We have one therapist at one location that is good with it, and so, again, I'm using it maybe once a year, if that, right, but it's just something to think about. It's not reimbursed in the middle. That's a big problem. Should be. George, you gotta help us with that. I have one question as an audience member, more than a panelist. I was recently listening to the ASCS podcast, and they were interviewing someone from Europe about the acromial morphology with posterior instability, and they had started to do acromial osteotomies to correct that. Have you seen or heard of that, and I guess, what are your thoughts on that concept? I mean, they've been done, mainly in Europe, but I would be much more likely to do a, like a Schiaparelli bone block in the back than I would to do that osteotomy. I just think with the, you know, with the nerve structures right there, it's a huge exposure. I mean, the concept makes sense. I'd just rather have some sort of block in the back. Again, that's just something that is, you know, to consider, right, on top of, you should go to that, having failed everything else we've talked about. Yeah, I mean, and for those of us who do arthroplasty, getting the acromion to heal in that setting is challenging, and so you really have to wonder, but I was just curious. Yeah, Nick, good, you know, it's a great point. The, you know, and just like you said on the arthroplasty, everything I'm almost doing the shoulder now is what am I not doing to compromise a reverse down the road, and the problem with posterior is it's probably a spectrum of pathology. Jill Walsh has taught us this. You get static subluxation. You get more retroversion. You get more problems. Brett showed this very nicely, but as you get out of the early, you know, the 20s, 30s, 40s, now you're starting to get a problem, and at age 38, 40, now you got 25 degrees of retroversion. That's not a great case for an anatomic. That's gonna fail early, and we know that now, so that's a, you know, everything I can do to preserve reverse down the road, because it's a continual posterior instability, and Jill taught us that a long time ago, so we gotta keep that in mind. You're treating a 20-year-old, but okay, maybe 30 years from now, you're gonna need a reverse, if not sooner. Great, let's get started on some cases in the last 20 minutes or so. Dr. Owens, do you wanna go through some of your cases here? I've got a few on here. This one's kind of a posterior instability, but more of a cartilage case, but this is one that's fresh for me. 21-year-old D1 linebacker. You know, he had dislocated during the season, returned to play, of course. Finished the season, had pain. This is the one cut that really shows it well, but this is MR, and you can appreciate the large articular cartilage defect, which comes all the way across to just about mid-glenoid. That's all I have, but these are the arthroscopic images. A colleague of mine scoped him, thinking it was just a loose body removal. Got in there, soiled himself, pulled a bunch of pieces of stuff out, called me from the PACU, and then by the time I got the kid back home from New Jersey, by the time I got him back, he's three weeks in a sling. He's in so much pain, and so anyone have any ideas on, you know, what do you do with this? This is a bad actor from the start. That MRI, you go back to that, and I don't know if you go, it's hard to go back on this. This is a, this is a, already, this is what we talked about. This is a B2 glenoid. If I see this in a 50-year-old, it's almost reverse arthroplasty. I can't do an almost anatomic on this. It's brutal, if they have arthritis, but that's the problem with posteriors. You got this, this plastic, plus their alignment, plus probably repetitive microtrauma. It's all a continuum, so it's a problem, and yeah, then now that you got a cartilage issue, then you get a lot of that extra cartilage, or bigger labrum. You get this kind of sequestrum of better cartilage and labrum there. You got hypertrophy of it, so it's a really good thing. The nice thing with MRIs, it's not terribly subluxed posteriorly. If it was, like, 70, 80, 90% posterior subluxation on that center glenoid, but I favor an arthroscopic repair for this first. I mean, I know you debrided it and everything else, but I would start an escopic, just like we talked about in my talk. See what they get out of it, but you are gonna need tune-ups on the shore going forward. Any ideas on cartilage? I actually asked Brian Waterman about this, and he used this technique, but leave me a show, we can go with it. Yeah, so initially, if that was your case, would you have fixed it and removed that loose body, or somehow tried to attack that cartilage? You know, he wouldn't, the other surgeon wouldn't describe it to me, but I think that cartilage fragment was attached to the labrum, and I think you could have saved a lot. Covered a lot with the repair, and then left the defect. He did, again, it was full thickness cartilage, but at least there was no bone loss, despite the mild dysplasia. So, and of course, he's a D1 transfer, he's a linebacker, wants to play, and it's now, this just happened in like April, right? So, we went in and actually- He made it through the whole season. He made it through the whole season, but yeah, they had surgery like March, and then I get him in like April, so of course he wants to play in the fall. So, actually, we went in, this is a view from the top. I don't know if this, there's a video, but it might be in the next slide, but he actually had a huge, full, you know, osteocondyle defect of the head, which was fascinating. I wouldn't expect to see that. And then you can, of course, see the glenoid. The bottom right is a video, actually. So, we pinned the OC fragment on the top with a couple of pins, and then we repaired the labrum, mobilized it, tried to close a lot of the defect, but we still had that full thickness cartilage, and I spoke with Brian Waterman about this, and he's one case, I think it was in VGSM or something, but we used biocartilage for this, and it actually filled in okay. You can see the upper right, that filling in. Of course, then the fiber and glue made everything kind of gooey, but he's doing well now. He's a couple months out, and we'll see about the fall. Did you advance labrum into the defect? We did, as much as we could. We knew we would still have something there to fill after this. It's much smaller after your labor repair than it was. It's just hard to access, and of course, his deltoid is like my booty, as it's huge. It's brutal. It's a long, that's the nine-centimeter cannula. It's a long cannula. Yeah, I mean, George, to your point, I mean, this is where we need you to help us get this line back for a couple more years, and if they got NFL aspirations, that's gonna be a tough draft pick. That's gonna fall in the draft. I mean, that's a huge problem, but if they function well and then do okay, it's gonna be great. The other thing I've done in this is a bone sponge, a bone disc, and sewed them in with the anchors, or also augmented with a proximal tibia autograft with a small auger. You just take an approximate tibia, like a seven-millimeter auger, and just pack in the autograft, jam it down a cannula, just like you do with a bile cartilage. You can go on to the next if you want. Sure. So this is a 17-year-old lats player. This is one that, again, the ED said he came out the front, and of course, everything's documented, but pretty clearly, he came out the back. You can even see a little small reversal sax defect on his head on the ax film, but he's clearly going out the back on exam. You can go ahead. He was literally because of his MR, and of course, you see, this is a GAD study. You can, of course, see not just a label tear, but also what looks like a posterior band IGHL or some sort of capsular disruption with extravasation of dye out. So we go on. This should be a video that plays. Again, regular cannula in the back. Then this is your seven o'clock portal there as well. There's a grasper showing that big capsular tear with a posterior label repair as well, and then play that slide again. This should be, again, we're showing that, and then hopefully, it increases speed. You can go back. It should play. So we did a label repair, then stitch that up as well. Brett, did you start from posterior? Some of these posterior cases that I've experimented with and kind of liked starting anteriorly with your viewing portal as opposed to posterior. Yeah, I started pretty traditionally coming in, and I don't usually ever really put a cannula through the traditional posterior portal, especially at the big eight, five. I just wanted to be able to, at that point, instrument a little bit better, and I usually will put a small cannula in my accessory postural part. It was an interesting case. Again, highlighted, you can't always have a label tear. You can't just fix that and go back. This was an obvious one, but it was one where you can't get both capsulars. Fortunately, the MRI showed it. Yeah, Brett, that's a great case, awesome work, and you can see that. That's a classic rent in the capsule to see with posterior. It's different than an anterior Hagel. That doesn't generally happen anteriorly. It happens posteriorly, and so just having that clear tear, you can see how you nicely got the hook under that tear, whereas a full traumatic tear, this patient will do well, and especially from our outcomes data, whether they have a Hagel or not, plus the labrum is really, he's gonna do fine. How often are you guys getting contrast? Is it, are you getting contrast MRIs with posterior instability more than anterior instability? It sounds like, Brett, you're getting a maybe more. I'm a big gadolinium guy. I know that's controversial, I guess, but I just like to, I think there's some subtlety that you miss without having that gad contrast there, so it's up to me. I get, obviously, if it's an acute guy, you can get him in quickly, you can do that, but sometimes there's delays, get him prior off or whatever, so I pretty much will order the gad study. I like gad. You can get a free test, like you get a really good cut, so it's good, but the gad is what we grew up on. CdHagelin comes out, it's so good every time you get it, but it's intervention, it's immuno-injection, patients come back, they're like, please don't do that again to me type thing. It's not the most annoying thing, so there's a cost to it, but it's diagnostically so secure. So here's one that you'll enjoy, George. 21-year-old guy, he actually works on a cruise ship, and so he's out at sea. Has a seizure, dislocates out the back, so to work comp, he goes to the ER twice with pain at different stops along the eastern seaboard. They don't diagnose him with anything. He comes back home and sees a primary care sports doc who didn't get x-rays, sends him for an MRI. This is a non-contrast MRI, right? I think it's a great case, right? And then, again, gets a quick call from the radiologist, soils himself, and then calls me on the phone. And so this is what you have. He's fortunately neuro-intact, he's got very little range of motion, 21 years old, seizure disorder, relatively under control, so he says, but he just seized. Not to cut Brett off, but this is the number one closed claim, medical-legal, from the Emory ER. Missed post-seizure dislocation. Why? Patient, George, super comfortable in internal rotation, right? Subscaps relax, they're internal, they wear a sling, oh, no issue, yeah, just kind of keep rehabbing it, keep stretching externally, and they keep making the reverse heel sacks worse. So number one claim. And so we were lucky to be able to reduce him in the OR, he's, again, he's a couple months out, but I was having a prior op. There's your reverse heel sacks, George, and that you asked about. And so everything was stripped off the back, we fixed that all arthroscopically, and I think, I hope the video shows, that is our reverse heel sacks. Reverse ramblosage right there. So I don't have, I have stills, and then the video of us sewing that subscap in. And he did really well. This is about a year out. You can go to the next slide, this is him, you know, at least, forward flexing. I just saw him about a month ago. He continues to seize, and he's got a horrible-looking contralateral coming out the front with huge bone defects on both sides, so. Looks like he's been okay. Do you have any tips to just be careful of the axillary nerve whenever you're grabbing subscap, or are you just visualizing anteriorly, making sure you're not getting too low and you're passing your sutures for that reverse ramblosage? Yeah, it's pretty high, usually. You really, you tend to be in the upper to mid subscap, you're not really getting all the subscap. Not too big of a concern. Honestly, I never even thought about the axillary nerve, but now you've given me something to worry about. You're the expert. The A word, I hate it. You know, the seizure patients, they're tough. And the problem is, when you're dislocated for a while, when you have other problems or you continue to seize, I love what Brett did, but at some point, you're gonna have to do a bone graft. Seizure patients need bone grafts in general because the soft tissue mechanics are completely stressed every seizing issue. And they always say, the neurologist says, clear, good, yeah, great. Then a week after surgery, they seize again. So it's always an issue. So I really like bone graft in these situations, but I think- And non-Latter-Jay. No Latter-Jay, please. No, no, no, no. Yeah, they'll pull the block off with the Latter-Jay. There's definitely a DTA all the way, front and back for these. Yeah, so we have a case of it. I don't know if you can- You're gonna pull yours up? Yeah, we can pull it up just as a segue. There's a, it's all the way to the end, but so the distal tibia fits the glenoid. We've kind of glommed onto the talus fits the humerus. So we've got quite a few, you know, pretty aggressive case series now of talus for reverse Hill-Sachs. And the reason is it's really hard, just like the glenoid, it's really hard to get a fresh glenoid. It's really hard to get a fresh proximal humerus or a fresh humeral head. So they sort of, we did all the studies with it again before doing it. And so this is probably about six, seven, eight years into it. They're not a ton of them, but using it for both reverse and regular Hill-Sachs now, and you can do plugs, you can do lemon wedges, whatever kind of fits in woodshop class. I'm getting there. A lot of slides here. Yeah. John, what have you done while we're getting this case up? I was just thinking, so I think the some, I agree with that without the latter Jay, personal experience from that. And then one of the things that, one of the things I think is helpful is I think that there's, I've had at least a number of seizure patients with large Hill-Sachs lesions without that much bone loss. And so I like the idea of grafting the humerus in those cases, because they're massive Hill-Sachs lesions. And I've actually done an open bank cart just because I don't, it's a compressive force on the Hill-Sachs if they do dislocate. It's not a shear or other force on the distal tibia or whatever it is on the glenoid. Recognizing that, you know, it's, I've done a subscap split. So they still have, you still have soft tissue concerns with a re-dislocation, but a distal tibia if they do dislocate. So tell us about your approach then. Yeah, that's an anterior case. Yeah. With a regular Hill-Sachs, do you want to take it all down or? Yeah, two approaches. I think you can use a direct posterior lateral split and access that. It's still challenging, but it comes off the posterior lateral border of the acromion. But, and you have to take down the infraspinatus, but you're looking right at it. It's a deeper hole. Or you can take a, if you're doing a formal anterior like approach, you have to take the subscap down in a full kind of arthroplasty type exposure. You don't have to take the biceps. So you can leave the biceps, but you can graft from posterior with a massively externally rotating. This is Dr. Preventer's case, reverse Hill-Sachs. Yeah, so this illustrates a lot, very similar to Brett's. This is a 35-year-old female. I get actually called from the emergency department and let's go to the next slide. She had fallen mountain biking, super active, super everything. And you know what? At least my ear unveils fantastic. You'd see a lot of orthopedic stuff. My ear colleagues are amazing. They only call us if they got a problem and meaning they need you. And so if you go back, yeah, if you go back to that Hill-Sachs, it's yeah. And this is, yeah, to Brett's point, the problem with the reverse Hill-Sachs, I think it's a bad name. I think we need to rename it because it's all cartilage. And the reverse Hill-Sachs is almost all cartilage because it's right up against the capsule. This is about a 40-degree defect of cartilage in loss of articular arc. So they got the CT. We brought it to the operating room, closed her dues, got some MRI, looked at everything else. And you know, that's where she is. It's a pretty big defect. Went in and Brett's gonna kill me because this is just me in the lateral. We're doing the lateral. You can see all the big tear and injury. We're gonna fix the posterior labrum in the lateral because that's just how I do it and can do it better in my hands. And so we fix the anchors. And then I roll her back. I go get a quick cup of coffee. We redrape in 10 minutes and open up the front. And we put in the talus allograft. So yeah, you can kind of advance, Justin. So, you know, be flexible in your aura. It only takes another five, 10 minutes. I just lean them back in the bean bag. You got great access. I use a Mayo stent. It's like I'm doing an open shoulder and an arthroplasty. Yeah, yeah, keep going, Justin. You can see it's just a really big, you know, high-energy injury. Keep going. Let's go to the, we'll go to the, yeah, keep going, keep going. We gotta wrap this up. So yeah, here's the talus. Basically, it's the medial side. You can also use the lateral side. I take down, I preserve the top of the, here, keep going. There's some better videos. I preserve the top of the, bottom part of the subscap, bottom two centimeters. Take down the top three centimeters and then put in the, I don't know why I'm saying that. Keep going. There you go, yeah, here we go. So here's the talus. He kind of cut some videos out, but. It fits almost perfectly up to about 40 millimeters. And it's all good, dense cortical cancellous bone. We're now doing plugs for this, if the plugs fit. Plugs can be a little bit of a challenge as you have to drill in them probably much longer in the right breadth than you would normally have to do. That's all headless compression screws and then fix the top three centimeters of the subscap. So it's not, none of this is for free. I mean, you gotta, subscap's an issue always with these. There's your CT in what, a year and a half or so. And you get a nice reconstruction of the tuberosity. So definitely have that in your ornitarium for some of these higher end cases. Can you use, what do you use or what tips do you have to fashion that to the right size? Back and forth to the back table quite a lot. Yeah. A bone wax model, a 3D printed model. And it's just, it's Woodshop 401. It's kind of fun, but it's back and forth, back and forth. And don't drop the graft. I almost did. Keep a couple of K wires in it. Great. I think we gotta wrap up here, unfortunately. Thanks everyone. It's not often we can get all these experts that taught us so much in the room. And thanks everyone for coming early in the morning. Thanks a lot. Good job, guys. Thanks.

posterior shoulder instability

arthroscopic bone block

failure mechanisms

risk factors

diagnostic procedures

contrast MRI

surgical techniques

portal placement

knotless anchor fixation

scapular dyskinesis

bone grafting materials

individualized approaches

dynamic stability