I've been doing patella oceanographs since about 1997. We're going to talk about some of that experience. Disclosures are in the program as well, here they are listed. Historically described as far back as 100 years ago, so what's old is new. Maybe what we're doing to tweak the system biologically is different, but these have been going on for over 100 years. Pioneering work by Dr. Gross and Marvin Myers in the 70s kind of re-fired the kiln for getting these done with indications, outcomes, and some basic science. We know the rationale is that it's essentially a transplantation of an intact organ of highland cartilage articular, and it's damaged in that area of the joint, and the mature cartilage surface is transplanted along with a thin layer of supporting sub-contour bone, three to ten millimeters thick, depending on the variability of the contour of the shape, particularly important with patella. It only requires a healing of host allograft bone through allograft bone incorporation, what we call and learn about in medical school as creeping substitution, that's real important. So we don't want to have too much bone, it's just too much biologic work. Success of a fresh oceanograph is predicated on the survival of the viable chondrocytes to maintain the cartilage matrix in concert with the appropriate host bone interaction and healing. So why not frozen? It's been done, it can work, but it's temporizing, it doesn't last as long. The survivor is dramatically diminished when we freeze the cells. There aren't that many cartilage cells in a big block of cartilage. Despite various cryopreservation techniques, it just hasn't panned out as well as fresh allografts that have consistently shown in our literature superior chondrocyte viability, and it's all about the cells, as few as they are. So we favor fresh tissue despite the greater difficulties surrounding the logistics, the availability, the procurement, now males and females, gosh, it's like so many things going on, and the use of fresh graft material. I would note that it appears that men accept female grafts better than women accept male grafts. I don't have to tell my wife that. Indications, woo, they're important, isolated, focal, well-contained lesions in a physically active person. We don't do these in senescent patients. These are active patients who want to get back in the game, whatever their game is. Not suitable candidate for total knee, obviously, that's the far extreme, absence of all but not limited to inflammatory or advanced OA, uncorrected instability or malalignment, often these are combined cases, as Dr. Cole has shown us in the literature, immunogenicity, we're lucky, we're immunologically privileged with the cartilage, intact cartilage is immunoprivileged, it's not that provocative, as well as we know to test at this point, at least. Immunology of fresh OCI grafts is not considered clinically important or relevant, and there's no attempt made right now, maybe that'll change in the future, to match donors and the recipients through immunologic parameters. So fresh OCI grafts, Dr. Gross, back in 1998, I was just out of fellowship, I remember when this paper came out, the short of it was, don't just think about the cartilage. You can put new carpet in the dining room, but if the floor creaks, before you put the new carpet in, the floor's gonna creak after. You gotta worry about the alignment, the subfloor, the bone, the stability of the whole contraption. It's a unit, it's not just cartilage, it's cartilage and bone, and he looked at a lot of knees over a lot of time, and they had really good results, considering they didn't have any biologics to work with at that time. Again in another paper, graft survival ranged from one to 25 years, based on their time to re-operation, and that was coined as the failure. With stable osseous graft base, the hyaline cartilage could, you know, he could tell his patients back then, they could last upwards of 25 years, we don't promise that to patients, it's still a bridge building operation, like many things we do in sports medicine. The post-op rehab is important, you can't just finish the recipe and put the new brick of cartilage and bone in the knee, you have to treat it with respect, while it's biologically incorporated in the creeping substitutions going on. So we limit weight bearing when it's a weight bearing lesion, despite the fact that it's well contained, isolated, focal, and hopefully unipolar in 90% plus of the cases. Sports aren't allowed for at least six to nine months afterwards, because that really has to not just look good, it has to feel good, and we know with second looks that it takes a while, and with surrogate MRIs it takes a while for that creeping substitution to take effect. So all these things come into play. So robbing Paul to pay Peter with larger graft needs immediately almost negates autografts. So autograft potential complications, you could have collapse, it could be if you take a big enough wide fisheye lens picture, your lesion's right where your donor site is, you're like, who's winning the battle there? You have to have viable chondrocytes, obviously, and contour matching is important, just as we're learning it might be sex matching as well. Cartilage thickness mismatch is important too. People have tried in the patella specifically, I describe to my patients always, it's double stuffed Oreo cookies, and one gets hungry, and you're like, that's twice as thick as the cartilage on the condyle, so you can't take condylar cartilage and think you're gonna match the three-dimensional nature and contour of a patella lesion, especially if it goes across the central portion of the patella with the crown. Here's a complex case, but not atypical, a little instability, a little malalignment, a lot of cartilage damage, and a prior meniscectomy, kind of the great bad knee. The plan, we're gonna do an unloading osteotomy, because we want to improve the environment, otherwise we're just knocking our head against the wall. We're gonna use an allograft ACL, because we're bringing in allograft meniscus already, oh, and the patella, you can't negate the patella, this is a patella talk, so this is the focus. And this young gentleman, who happened to be a laborer, had a known grade four patella lesion, but by the time we got in there and got it approved with all this surgery and graft matching, he also developed a small groove in the trochlea, so we did some off-the-shelf cartilage work. So these are cases that are doable, they're outpatient still, it's just a lot of work rolled into one, a lot of codes, but you don't get paid as well, but you come out, when you do a lot of them, you can do it in under two and a half hours, you can do the HGO certainly in about 40 minutes, the transplant, of the meniscus and ACL prep, combined with the placement, about an hour and a half each, and then the OC is really quick, actually, and we'll go through the technique. So here's this guy's knee, pretty good-looking cartilage, but no meniscus, ACL hugging the PCL, but not the notch at all, so it's a non-functioning ACL. Prep a lot, it's all about prep work, then putting everything in is pretty easy, medial notchplasty, eminenceplasty, posterior horn retrosockets, with your technique of choice, you have to see, if you can't see, you can't put, if you can't put it in, you're gonna be scratching your head about an hour and a half into the case. Prep for the revision ACL, get all the sutures passed, the meniscus is already in, it's with bone plugs, so it's more anatomic in my hands, the meniscus is in, and then we open it up, flip it, the biggest part of the surgery for the quickest part of the case, bigger arthrotomy, flip the patella, and do what we've called for 20 plus years, a mega patella OCA, it's basically a new press-fit cork with bone and cartilage, with minimal bone, actually. Here's the guy, post-op day one, this is him, he had the HGO, the ACL, the patella OCA, he had a BTB that failed, so I extended that incision at the end of the case, everything was arthroscopic, and that's the extension northbound there, with my hand. We're just checking his incisions on day one, because he lived in Connecticut, which is a very small state, but he lived on the far side, so I wanted to see him the next day, he stayed in the hotel, and came back in, and he could actually do a straight leg raise, because he had sensory blocks, which you can do all this, and not negate the big part, the OCA graft, which in his knee was the elephant in the room, he had some instability, but he couldn't go up and down stairs, and he was a mover, a laborer, he moved, he was in a moving company, he didn't do a lot of the moving anymore, he owned the company, young guy. This is a patella chondrolesian case, this is a 38-year-old female, with a 3-month history of right knee pain, she was a softball player, I think she was a catcher, she worked now in septic tanks, so she was up and down equipment, digging holes in the backyards, and hopefully in the backyard, not the front yard, failed rest, activity modification, anti-inflammatory is the typical, pain localized to the medial aspect of her knee and the patella femoral joint, she had significant difficulties doing just normal work, and she walked with a significant limb. So this is her imaging, not too dramatic, patella stability, TTTG, everything was normal, she never had an instability event in her life, she was an isolated focal traumatic patella chondrolesian. On exam she had typical crepitants and catching, it's debilitating, you can't walk and you can't go up and down stairs, no instability, normal tracking, and medial compartment pain. So we knew, after our arthroscopic findings revealed this grade 4, 20 by 15 lesion on the lateral facet of the patella, so it didn't go across the keel, and a 12 millimeter grade 3, 4 chondrolesian, so we're going to hit her with a kitchen sink. We asked for a medial femoral condyle and a matricized patella. Here's her fibrillated crab meat coming off the dome of her cartilage on the patella, we've trimmed it back, you can kind of see the dimensions there a little bit. Here's her medial femoral condyle cartilage lesion, just prepping it up, trying to make sure we got the full size before we open it. Medical course, she's still complaining of medial compartment pain, after we debrided it, this is part one, we stage it, you can't just go out and buy $12,000 of grafts, you have to validate to you, the patient, insurance carrier, the need for these grafts, they're a precious gift of life that we take seriously. So here's stage two, right to the open arthrotomy, you know, we know what we have, we've measured it twice, we've looked at it, taken pictures, we've audited, they've arrived, it's gotten approved, we do the patella OC, we drill the base, we add some biologics for any mismatch so we don't have any gaps, and we do what's important in the past six years, adding biologics, we do this canaliculization is what we're coining it as, it's just retro drilling the backside of the plug, because that's just, to me, foam bone, it's a space holder. We want it to creepingly substitute, so we're helping it along. We're giving drill holes for imbibation of the pulse lavage to get the marrow elements out in its sweet, deep center, the Oreo spot of that cookie, so when we pulse lavage, we're not compressing the material, we're actually getting it a way out. Then we suck it dry, that's real important, so then we drip in our ACP, PRP, or BMA, or whatever you want to put in, a biologic, I think, is important to help jumpstart the healing that allows the canaliculization for impure vascularization, and it doesn't collapse, it's still strong, you can see it there on the left. Here we are dripping in, we suck out all the fluid from the pulse lavage, just normal fluid out of the bag, and then we drip in about three times as much PRP, it literally sucks it in like a sponge, so it's really a nice technique, just simple, not that expensive, but I think biologically very effective. Here's what the patella looks like, here's your medial femoral condyle, very happy camper. Back in 2017, I was still looking at our West Point cohort, and we looked at osteochondrograph transplantation of the patella, minimum two-year follow-up, we were talking to the Surgeon General trying to get money fenced off to keep the project going at that time. We had to show some durability and viability, and that was from 2010 to 2013, we had everyone that was, you know, kind of military age, over 18 and under 45, I think, in the end. Pre-opted data, we looked at their sex, BMI's were all pretty good, they were mostly active duty. They filled out a questionnaire, this was a long-term follow-up, many of them were deployed and doing all the things they're doing this last couple decades. Results, 14 patients completed the final outcome, average age was 32 as expected, 12 of 14 were very happy they had surgery, I added very, they were just happy. Modified Doburn Postel was 15.5, that's pretty good. In the end, three of 14 rated their involved knees as 100%, so they weren't perfect, and the SANE scores weren't great either, they were 68.6. These are hard-charging patients, with one of the most common non-combat injuries that gets people boarded out of the military, anterior knee pain, but these, we decided to take them on. In conclusion, we thought that oceolographed transplantation of patella was a viable option for young to middle-aged patients with significant patellar lesions, not unlike other reports in the literature. The last one I'll end with, recent case, 28-year-old, grade 4 patellar lesion, prior subtotal meniscectomy and a torn ACL, very common to get this, plan was a transplant, revision ACL, lateral lengthening, and an open mega patella, because she was tilting a little bit, but she was not unstable. Here's her meniscus, you can see the blue markings from the back table, the allograft, and here is her patella. That, obviously I'm going to show you our best one, but that looks like, you know, we took her patella that she had in her back pocket, a spare one for this knee, and put it in. You can see it's good, viable cartilage, it's a new patella. And we've done some second looks for different variable reasons. This one was actually a quick one, got stiff real quick, couldn't get into therapy, was a far-flung patient, clicking and popping, so we thought it was just a big plica based on some imaging, and we did arthroscopy. It wasn't the patella, it was a big, fibrous strand of collagen going across the patellotrochlear region, like a monster plica. Doing well now, I just talked to her, I'm down in Texas now, but we talked to her, called her on the phone, she said she had a SANE score of 95, so she's doing very good. Save the patella. Thank you very much. Thank you, Tom.

osteochondral allograft transplantation

cartilage damage

patella

fresh grafts

chondrocyte viability