Thanks to AOSSM really for having me and thank you so much for not letting me follow JT. So, here are my disclosures which are not relevant. So, we all know that children's stability in the young populations is problematic and is particularly problematic with risk factors such as young age, male contact athletes, and we also know that bone loss amplifies those risks pretty significantly. And I guess the question we need to ask is what is critical bone loss in 2022? We know that bone loss is two flavors, glenoid and humeral sided. And we'll talk about sort of what glenoid bone loss is in comparison to traditional metrics versus recent literature and how much you can accept for soft tissue stabilization. And then our concept of the humeral bone loss continues to expand with bipolar bone loss and the glenoid tract concept. We know that glenoid bone loss occurs in a great majority of patients who have recurrent anterior instability and particularly patients who fail prior arthroscopic stabilization. And we all know this study from Burkhardt and DeBeer that if you arrive at the inverted pair scenario, you have a very high risk of failure following arthroscopic stabilization and that increases pretty significantly when you're talking about contact athletes including over 90%. Well, how much is too much? If you look at traditional metrics, this is a classic study with Utoi that was essentially reproduced by Gerber around that time. And I don't think there's any real controversy that if their bone loss is more than 20-25%, you need a bone procedure. But if you look at more recent literature, this is a paper out of Shin et al looking at cadaveric sectioning of bone and at 15% or more, soft tissue reconstruction did not reproduce normal kinematics. And then the same group looked at this clinically and they found that at 17.3%, that was their threshold for when an arthroscopic stabilization might not be a good idea. And then JT and his group looked at their active military population and they found that at 13.5%, maybe that's the threshold in which an arthroscopic stabilization would not be acceptable. And I think the interesting thing about this study is that even when they did not have recurrent instability, they still had unacceptable patient-reported outcomes independent of recurrence. And this same threshold at 13.5% was also reported by Dickens and colleagues as the threshold as to whether you might want to consider a non-arthroscopic procedure. So if you look at the summation of all these studies, the threshold for critical bone loss may be in what we would consider in the subcritical range in 13.5 and 17.3% and at least that target is moving. And then even more recent literature, maybe that's 10%. If you look at risk factors particularly of age and contact athletes. So I think the point is, is that this concept of critical bone loss continues to be really, really fluid. And of course we know the glenoid tract concept, including bipolar bone loss. And as has been alluded to, Giacomo Telli and Burkhardt, you know, came up with an equation to say, okay, what heel-sex lesion is going to be problematic for recurrent instability? And of course they termed the on versus off-track, which I'm sure all of us are very familiar with. And it's also worth noting that if you have glenoid bone loss, that decreases your glenoid tract and makes your heel-sex a much more problematic issue. So we know that the glenoid tract and the role of the remplisage is useful for off-track lesions. For off-track lesions, it will decrease the risk of recurrence pretty significantly and there are good midterm follow-up studies that demonstrate good return to sports, low recurrence, relatively good outcomes. And the question is, are all on-track lesions created equal? And our fellow Aaron Barrow just presented this, but we looked at this in 2021 and we came up with the term of distance-to-dislocation to describe how far the on-track lesion is from becoming off-track. And those with low distance-to-dislocation, we term a near-track. And we kind of thought of this more of a continuous variable rather than a binary concept. And as this was presented, when using receiver-operator curves, when the distance-to-dislocation was less than 8 millimeters, the failure rate was exceedingly high for these near-track lesions. And that became even more prevalent where the threshold became even less with younger age. And I think this makes some intuitive sense to most of us because a 1-2 millimeter on-track lesion is probably very different than a 14-16-20 millimeter on-track lesion. Well then, we just presented this as well. And we kind of looked at this in more granular detail. All patients who went to arthroscopic Vanguard alone, all on-track lesions, two-year follow-up, the closer you got to being an off-track lesion, the more likely you were to fail. And that inflection point was around 10 millimeters. And again, the interesting thing is for collision athletes in particular, if you have a contact athlete that's well on-track, you still had a substantially higher risk of recurrence even if you're on-track. And so this near-track concept may not even be a applicable to collision athletes. And so the summation of this study was really two things. It matters how far an on-track lesion is from being off-track. And then an arthroscopic Vanguard alone for collision athletes who are well on-track may not be a suitable treatment. And so for these patients, maybe there is something worth considering adding a REM plisage for on-track lesions or something that's a little bit more aggressive such as an open Vanguard or a Latter Jay. Well, what if you add a REM plisage with on-track shoulders? This has been presented at ASAS Fellows Day Symposium, but this was the question that was just posed. And in these patients in which we included an on-track shoulder in high-risk patients, so all these patients had on-track and the difference was REM plisage versus no REM plisage. In our high-risk groups, the ones who had a REM plisage had a substantially lower risk of recurrence in our control group. And the other additional find is when you add a REM plisage for these high-risk patients, it lowers the risk of recurrence by almost 99%. So again, these are for all on-track shoulders. This concept that contact athletes are problematic isn't really a new concept. This is a paper from Marciaro and Mazzocca essentially demonstrating for off-track shoulders with subcritical bone loss, the Latter Jay still does better than an arthroscopic Vanguard with REM plisage. And so we're all familiar with this algorithm. I think really the questions posed in the year 2022 are what is critical bone loss? Is it any, is it, it might be somewhere between 10 to 20%. Is there a role for doing a REM plisage for near-track lesions? So again, on-track shoulders that are not off-track. And does this algorithm even apply for contact athletes? So the take-home message of critical bone loss in 2022, one, 20% I think is still the textbook answer when you need bone procedure. Two, rethink where critical bone loss is in 2022. It may be anywhere from 10 to 20%. So really think about where the arthroscopic Vanguard alone is the right procedure. And when you're talking about bone loss in 2022, it's a bipolar concept. And so there remains some questions regarding whether, what should you do with a near-track lesion? What should you do with collision and contact athletes? Now changing gears really quick, the next question really is which surgery you're going to choose and there are really three flavors, right? Arthroscopic Vanguard, open Vanguard or some kind of bone procedure, Latter Jay or other. I think modern literature for some time is operating on the assumption that arthroscopic Vanguard and open Vanguard are similar or equivalent in outcome. But is that really the case? And I would contend that arthroscopic Vanguard is not a cure-all and you really should be thinking twice in considering these scenarios, subcritical glenal bone loss, near-track or off-track lesions, contact athletes in situations of the multiple recurrent dislocator. Our European colleagues have provided us compelling evidence that Latter Jay is a great procedure, low rates of recurrence, long-term follow-up. But I think the hesitation with this is that, you know, mainstream Latter Jay, we all can't be Joe Walsh and we know that even in master surgeons up to 25% complication rates and these can be particularly devastating in the youth population. And additional limitations of Latter Jay, you can have a large variation in coracoid size and you can still have a persistently off-track lesion following a Latter Jay. And there may be some bone loss that's over 40% and you can, you might need to consider other graft choices. And I think that's what's led to other research on other graft choices such as DTA, distal clavicle autograft, bone, arthroscopic bone block procedures. And I think more research is forthcoming regarding their comparison to the traditional Latter Jay. And then lastly, don't forget about the open Vanguard. We kind of went from A, arthroscopy to C, coracoid transfer. And then we kind of forgot about B, the open Vanguard altogether. Look at the pool of recent systematic, or recent studies including systematic reviews. Recurrence rate, 1.6% with Inviser. Pagnani, 2% recurrence. These are mostly contact athletes with bone loss. Other studies demonstrating very low rates of recurrence, 10%, 8.5%, 11 and a half years. And last I checked, these recurrence rates are much lower than most reported arthroscopic Vanguard failure rates. So at the end of the day, what you're going to choose is probably a risk benefit complication profile. So as you go from left to right, it's going to be a decision regarding the risk increase to the right, but also the rates of recurrence likely also decrease as you go to the right. And depending on the clinical scenario, there's probably a sweet spot for each of these procedures. So which surgery are you really going to choose? In the American algorithm, if you have no bone loss or no critical bone loss, you're probably choosing something soft tissue. If you are, if you're in the range of critical bone loss over 20%, we're probably choosing a Latter Jay or some other bone reconstruction procedure. But if you're in the subcritical range, 10, 13 and a half percent to 20%, the literature really is kind of all over the place and really could argue to do any of the procedures. And it's a really gray zone category. And obviously if you're European, it's very easy you're doing one procedure. I want to put in just a quick shameless plug for the OASIS trial of which many of you in this room are a part of. This is a multi-center trial. It's a civilian and military site, randomizing the patients in the 10 to 20% glenoid bone loss cohort to an arthroscopic open Bankart and Latter Jay. We've recently enrolled the first two patients. And we hope that the results of this study will shed some more light in terms of the gray zone scenarios in particular. So lastly, this is a treatment algorithm. I think it's useful in 2022 first to understand what the patient's expectations are. Second, understand what the risk factors for recurrent instability. And third, once the decision is made to go to surgery, what is the level of bone loss? And again, that comes in the level of glenoid bone loss, no bone loss, subcritical and critical bone loss, or pill sacs issues, whether that's on track or off track. And your decision making will depend on all of those factors. And I think there are certain scenarios we really still need more information. Contact athletes, near triclesion, subcritical bone loss. Thanks so much. Thank you.

critical bone loss

young populations

instability

recurrence rates

surgical options