Thanks, Matt. Those are great segues into this talk, which will kind of be a summary of all those things. I have no industry conflicts. So this talk, we'll talk about what things should guide our treatment in treating these osteochondral lesions of the tail or dome, and obviously, we'd like to think that our treatment should be guided by the evidence, but when you look at the evidence on OLTs, you have to ask yourself, how good is the literature? We know that level of evidence, one is the gold standard, looking at systematic reviews of RCTs or individual RCTs, but when you look at the level of evidence for osteochondral lesions of the tail or dome, as Pinsky did back in 2016, you see that 90% of the studies were level four, with a mean Coleman score of 53.6, with significant weaknesses in study size, study type, description of the post-op rehab outcome assessment, and description of the selection process, and the overall conclusion was that most studies assessing clinical outcomes of cartilage repair of the ankle are of low level of evidence and poor methodologic quality. So in most areas of orthopedics, when there's insufficient evidence from good data, how do you base your recommendations? And sometimes, under those circumstances, consensus-based expert opinion can help practitioners fill the gap and help clinicians to make their individual treatment decisions. So back in 2017, the end of 2017, we had a consensus meeting hosted by Dr. Kennedy and Dr. Ferkel, and hosted by this guy right here from Pittsburgh, and it included a lot of the leaders in the field, and as you can see from the picture, a tremendous number, and to gain consensus is a bit like herding cats, but we were quite successful in doing so, a lot of great discussion, and I would suggest that anybody interested in this look at the foot and ankle supplement from 2018, which was dedicated to the summary of this consensus statement. So we'll be looking at some of those during this talk. So what we'd like to know is what lesion characteristics are that should influence our approach, because if we know that some are gonna do well with a minimal treatment, then that's what we want to do, but if we know that some are not going to do well, then we really should be thinking about being more aggressive in our surgical approach. So some of the factors are certainly the size of the lesion, the location, whether it's contained in the presence or absence of a cyst, and our treatment decisions should factor in these parameters as we decide how aggressive are we gonna be. So talk about lesion size. This has been alluded to in the previous talks. If you look at some of the data, the studies that are quoted most often are this one by Choi, which showed that using microfracture for treatment of osteochondral lesions, the Taylor dome, if the lesions were less than 150 square millimeters, only a 10% failure rate, over 150 square millimeters, 80% failure rate. Similarly, this study back in 2008 showed that if the lesions were less than 15 millimeters diameter, no failures, only one success greater than 15 millimeters, and the 15 millimeters diameter correlates pretty well with 150 millimeter surface area. Now, Kennedy's group, Dr. Ramponi actually wrote the study, they did a systematic review of the literature, and what they looked at was 25 studies, almost 1,900 ankles. And again, it will show you that 88% of the studies were a poor level of evidence with poor inconsistent methodologies. They used the AOFAS score for an evaluation score, but there are no validated scoring systems for OLT. The conclusion of that study was that our current recommendations, as I just point out, are not supported by the clinical evidence, and that the current evidence would suggest that bone marrow stimulation should probably be reserved for lesions only about 10 millimeters in diameter. What about medial versus lateral? Most of the literature that I've looked at will tell you that lateral lesions tend to do better than medial, whether you do open reduction, interfixation, or fragment removal. My experience is that these patients do much better than medial, and I would even make the argument that papers should not be published grouping the two together, because I think that you're grouping one group, the laterals, that have a much better tendency to do well, and the medials are a completely different animal. What about containment? Choi's study showed that shoulder-type lesions, the uncontained lesions, had a substantially worse clinical outcome than those of the non-shoulder lesions. But interestingly, in their study, they didn't show any difference between medial and lateral. So when we looked at the consensus meeting, there was strong consensus, unanimous consensus, that bone marrow stimulation should be considered for surgical treatment of full-thickness chondral or OCLs that have failed conservative treatment, and strong consensus that the ideal size was, as we said, less than 10 millimeters diameter, less than 5 millimeters in depth, and that the ulcers that you use should be small. This goes along with some of the published data on treatment of osteochondral lesions using debridement and bone marrow stimulation. And Nick Van Dyke's group, this is from his group, published several of these electronic database analyses, and basically what they show is that whether you use OATs, bone marrow stimulation, or ACI, all three are effective treatment strategies. As you look for further support for BMS, there's plenty in the literature, as I've shown here. I'll point you to the DOMIN systematic review, bone marrow successful in 82% of primary lesion, and TOLL systematic review, mean AOFA scores of 90 at six-year follow-up. So in at least the medium-term follow-up, bone marrow stimulation does well. And do the results hold up over time? There's a little controversy on that, too. I know it was mentioned in one of the other papers. We know that fibrocartilage is inferior to articular cartilage, and when Rick Ferkel looked at this in a long-term follow-up with average six-year follow-up, he noted in 17 of the patients that had been evaluated five years previously that there had been deteriorations in the result. When Van Bergen looked at patients with follow-up of 12 years, what they noted, as you can see here, was that there was X-ray progression in about a third of them. But it's interesting that the mean AOFAS score, still at 12 years, was 88. So at least for a non-validated outcome score, it was still doing quite well. Batcher looked at 15 patients with arthroscopic microfracture, again, average follow-up eight years, pretty long. And they, interestingly, found no difference between the T2 properties on MRI scan and the repair tissue compared to native articular cartilage, despite the fact that we know that it's fibrocartilage. What about articular cartilage replacement strategies? Well, again, in lesions that are greater than 15 millimeters, I think that the data would show that you really need to start thinking of something other than microfracture, because the chances of you having success are much, much smaller. So again, these slides are courtesy of John Kennedy. Osteoarticular autografting certainly has, I think, the most support in the literature ever since Dr. Hengadi started doing them quite some time ago. And again, you all know this. This involves usually an open exposure on the medial side through a malaria or osteotomy debridement of the lesion, and then grafting from the knee. Again, those studies that they showed showed a not insignificant knee issue also post-operatively, although those symptoms are usually small. And again, good internal fixation, good-looking MRI scan afterwards. When you look at the OATS results, Shimazono reported in 2018, with an average follow-up of 26 months, better follow-up for the autografts than the allografts on the MoCART scoring. And Fraser in 2014 reported on 21 professional athletes, and 90% still competing at follow-up of about six years. Again, here, donor site symptoms in about 11%. So again, there are other options. This chondrocyte implantation was... The person that's probably done the most of that is Rick Ferkel. These are slides from him. And this involves articular cartilage harvest, chondrocyte expansion in the laboratory. They're injected under a membrane of periosteum. And this has been supplanted more recently by embedding them on a scaffold in the Macy procedure, which makes it a little bit easier than the tedious procedure of sewing down periosteum over the top. Pros of ACR, you presume we get articular cartilage as opposed to fiber cartilage. And you can reconstitute the bone with a sandwich procedure by putting bone graft in. The cons are significant, though it's a two-stage procedure. The ACI is technically difficult. The Macy is easier. But there's a big cost issue and insurance coverage issues. But Rick has good results and show that in medium to medium-slash-long-term follow-up of 70 months, that the AOFAS scores hold up and the patients are doing well. Talk very briefly about some other options that have been suggested more recently. Juvenile articular cartilage was looked into by Eric Giese and Chris Coetzee and others. It has the benefit of being prepackaged. It has a shelf life, so you can keep it on the shelf. And it's a relatively easily performed arthroscopic procedure where you debride the lesion, microfracture, put some fiber and glue down, put the cartilage, and then put fiber and glue over it. I think that the literature is not great on this. There's short-term follow-up. And again, when you look at a follow-up of 16 months and 78% good to excellent results, I think you have to go, well, OK, I could get that with microfracture, too. And so the proof would be in the pudding on those. Pros are that it's easy, arthroscopic, and presumably get articular cartilage. But the cons are literature support isn't great, cost. And I have never been able to get an insurance company approval for it personally. The ideal procedure would be arthroscopic, inexpensive, covered by insurance. And if not covered, at least not too expensive. And you've seen some of the things we're talking about here. There's autologous matrix-induced chondrogenesis, which has some support in the literature. There's bone marrow stimulation, and then covering with a collagen type 1-3 membrane. And in trying to figure out a cost-effective approach for the higher-risk lesions, you see some of these micronized articular cartilage things that we're talking about here, which again, as you can see, have no real good long-term support, but certainly, I think, are interesting at looking at for the future. And they certainly deserve some good studies, a level one type study where you actually do a little bit of prospective, randomized, and comparative studies. Again, these are courtesy of Arigeza, using the dehydrated micronized articular cartilage. Low cost. You can do it arthroscopically. But as I put it together, I would say this. Think of it in the Venn diagram. If you've got small, 100-millimeter or so lesions, I'm personally still sticking with microfracture, possibly with PRP or BMAC. I think when you start getting to the large lesions, you do have to start thinking about other alternatives. OATs, you can never argue against. OATs allograft probably has slightly not quite as good results. For big, big lesions, you think about bulk allografting for hemitalis. When you're in the middle, I think there's a lot of considerations. You have to look at the size, whether it's medial or lateral, the depth, and the level of containment. Those are ones where I might consider doing a bone marrow stimulation with something else, such as the allograft, autograft, or the biologics, or even an OATs, depending on the lesion. That's kind of how I put it together. Thank you.

osteochondral lesions

talar dome

treatment

consensus-based expert opinion

lesion size