My name is Brian Haas and I'm from UC Davis. I just want to thank AOSSM and also Cassandra Lee for inviting me to give a talk today for this conference. The title of my talk is Discoid Inferno Hot Takes on the Management of the Discoid Meniscus. I also want to acknowledge the PRISM Meniscus Research Interest Group, PRISM being Pediatric Research in Sports Medicine. I'm a member of the PRISM Meniscus Research Interest Group and I'm going to be talking a little bit about some of the research that we've been doing as it pertains to the discoid meniscus. So what is a discoid meniscus? A discoid meniscus is a failure of apoptosis and autophagy of the central part of the lateral meniscus during the first eight to ten weeks of development. Its incidence is around five percent of all lateral meniscuses. The discoid meniscus usually becomes symptomatic in the child sometimes as early as two years of age and usually it presents itself as a snapping knee and sometimes in the really young kids the parents will come in and say that their kid's knee is snapping. It can also click and cause mechanical locking and oftentimes in most patients becomes symptomatic later in adolescence when a tear finally develops. On physical examination these patients usually have mechanical symptoms which are most pronounced in extension and they will have a snapping of the joint when you extend the leg and they will also have joint line tenderness associated with any tears. The knee can also be locked or can actually have a lack of extension and is usually positive to provocative testing. In the workup of a patient with a snapping knee of course you want to obtain the AP and lateral of the knee and things that you're going to look for when you're thinking about a discoid meniscus as seen on the AP view is sometimes a widened joint space. Now not all patients have this but it can be there up to 11 millimeters. There's also some evidence of squaring of the lateral condyle, cupping of the lateral tibial plateau and sometimes there can also be a hypoplastic lateral intercondylar spine as seen here in this x-ray. When you are concerned about having the patient having a discoid meniscus you also want to obtain an MRI and the classic MRI findings and criteria to determine whether or not a patient has a discoid meniscus is a thickening of the lateral meniscus as seen on the sagittal plane greater than three sequences or on the coronal plane greater than 15 millimeters. An MRI can be used to determine whether or not the meniscus is complete versus incomplete and sometimes it's helpful to get MRI special meniscal sequences which go through thin slices to help determine if a patient truly does have a discoid meniscus. The classic Watanabe classification is one that most people are familiar with and it is the one that's been around for some time with the following classification type 1 being a complete tear I'm sorry being a complete discoid meniscus type 2 being an incomplete and type 3 is the Risberg variant as you can see here in this in these pictures. Minn-Coker's paper from AGSM in 2004 showed that in a population of children that had the discoid lateral meniscus 62% had a complete discoid meniscus and of those 70% had a tear and 28% had instability. I just wanted to review something that is I believe relevant to discussing discoid meniscus in terms of its treatment and just reviewing the meniscus vascularity and cellularity. We know from Arnosky's classic papers that vascularity is present in the entire meniscus at birth and then after that it does regress from there where at nine months the blood supply is in the outer two-third but by age 10 to 12 the outer one-third is where the blood supply is limited to. In regards to cellularity it is believed that children have overall more cells in their meniscus than adults and this may explain why children and adolescents have better healing potential than adults. In regard to the treatment of discoid meniscuses if the patient is otherwise asymptomatic and there's an incidental finding or the snapping is not too significant then the initial treatment is always observation. However unfortunately many of these patients ultimately go on to having symptomatic knees and the historical treatment of a discoid lateral meniscus was actually to take the entire meniscus out. This is historically where it was thought that the meniscus was too degenerative to really save and so the meniscus was taken completely out. Unfortunately studies ultimately showed that this was not a good strategy as these patients ultimately would have a pretty significant accelerated loss of cartilage on joint space and many leading to angular deformity and degenerative changes as seen here in this patient who had a complete meniscectomy at age two. The historic treatment once it was shown that taking out the entire meniscus was not the best way to handle things efforts have been changed over to saucerization which is essentially sculpting of the meniscus to try to make it shaped more normally and then repairing any type of instability and this treatment is based upon the Risberg classification where type one discoid meniscuses you try to saucerize it down to about a six millimeter rim and a type two arthroscopic saucerization to around an eight millimeter rim and then the unstable type threes you perform a reattachment and this is either arthroscopic versus open and you do a meniscal repair and apply sutures across the unstable part of the meniscus. Overall the saucerization has been around for some time as the treatment of choice for discoid meniscus however there's not really any good long-term studies in terms of how these patients ultimately do. Ultimately given the limitation in our understanding of the outcomes for lateral discoid meniscus the PRISM meniscus research interest group had a specific interest in trying to understand better about how to treat these patients best and as part of the PRISM meniscus research group we developed a new classification scheme which is arthroscopic which I'm going to go over here. I just want to acknowledge all the members of the PRISM discoid meniscus research interest group who contributed to this work. Essentially the PRISM arthroscopic discoid lateral meniscus classification system is the first arthroscopic classification and the point of it really is to help better identify and classify the discoid meniscuses in much more detail than what is what is provided with the Risberg classification which is really pretty rudimentary in terms of understanding the complexity of these patients. The arthroscopic classification system is as performed using both lateral and medial portals in order to evaluate the discoid meniscus and there's four essential things that are looked at. One is overall the width and the surface area, the second is height, a third is stability and fourth is the type of tearing and this is essentially a chart showing that and this has led to two recent publications one in AGSM the other one in arthroscopic techniques and I'm going to review those here in one minute. The meniscal width and surface area is essentially performed by looking at putting the camera in both the medial and lateral portals and looking at the overall surface of the tibial plateau which is covered by the meniscus and the classification is defined by an incomplete where the meniscus covers less than 90 percent of the tibial plateau whereas a near complete or complete is greater than or equal to 90 percent of the tibial plateau covered and in a series of arthroscopic reviews of discoid meniscuses it was found that approximately 50 percent of meniscus discoid meniscuses are incomplete and approximately 50 percent are near complete or complete when using this classification system. The second way to classify the discoid meniscus is to measure its height essentially where a probe is inserted into the medial and lateral portals and measured basically normal versus abnormal in terms of relative to normal meniscal height and in this classification system 46 percent are found to have normal height whereas 54 percent are found to have abnormal height. The next is assessing the stability of the meniscus and its meniscal capsular attachments and abnormal stability can be secondary to absent meniscal capsular attachment and can also be present but lax with deficient attachments. Essentially this was performed in both the medial and lateral portals where the meniscus translates past the midpoint or the apex of the convexity of the lateral formocondyle. Notable is also an enlarged popliteal hiatus which can be seen which was also measured. Essentially when looking at a group of discoid meniscuses 47 percent were found to have normal stability where 53 percent were found to have abnormal instability. The posterior half of the discoid meniscus is the most commonly found to be unstable in 29 percent whereas 19 percent have anterior instability and five percent are unstable in both positions. And finally the last part of the classification system that is measured is looking at the type of tearing that is seen in the discoid meniscus and essentially the classification system looks at both the tear type and the tear location. In this series there was 62 percent either had no tear or the tear was in the central portion or the saucerization zone and then those that had a tear 25 percent were noted to be horizontal and 13 percent were degenerative complex or radial. The location the posterior half was notable in 20 percent whereas 14 percent was the tear was both anterior and posterior and then finally localized anterior tears were rare in only four percent. And there's a video that was published as part of arthroscopic techniques which I'm going to attach here for your review. What we have so far with blocking and then maybe if we can attach that to the end of it. Also, that do you have any closing remarks or anything? Yeah, so. You're still recording, right? There's a way to, like, cut the video down, but. Yeah, I mean, here's the I still have more slides. I wasn't done. OK, I have a little bit more to go. I have, like, a couple more slides, but, um. That video is like, I mean, you can download it from that's what I'm thinking. I just because you have more than after that. Yeah. Let's end it right now and I'll tell Julie what we've done and then. If we can add that video in somehow, and then we could come up and do the 2nd part after. Does that make sense? Should I just do the 2nd part now? Um, then you have 2 parts and maybe some conversion. That's what I'm thinking. I can just do the 2nd half. OK, let's do the 2nd half right now. I'll just do that and then you'll have my recording and then I can show you how to get the video. It's it's it's downloadable on online. I just don't know how to do it. Like, OK, that's too bad. I was hoping you'd be able to hear it. Yeah, I did. I didn't hear anything. OK, all right. Start you start, like, from. After the video, you want me to just go ahead and start. OK. A table showing the frequency of discoid meniscus features is included here for your review. So one thing that we're going to be working on in the lab tomorrow, we'll be going over some of the surgical techniques that are important when taking care of a patient with discoid meniscus, but I'm going to review them here, essentially. The first is to identify the width, the surface area, the height, and the stability of the discoid meniscus, and it's important to use both the antero-medial and the anterolunar portals to assess the discoid meniscus, especially when assessing the stability. The antero-medial portal allows for more complete assessment, especially in anterior instability. Once this is performed, the goal is to saucerize the discoid meniscus to a width of approximately six to eight millimeters, and then it's also important to assess for instability and tears both before and after saucerization. Sometimes with the more complete discoid meniscuses, it is difficult to note any tears or instability until some of the saucerization is performed. Once the saucerization is complete, you should then work on repairing the instability and repairing any tears, and in general, these meniscuses can be very unstable, and so it can be helpful to first pass some inside-out traction sutures that can be wrapped around the meniscus outside the knee, and then you use those traction sutures to help reduce the meniscus so that you can do further repair. Once this is performed, you can then go ahead and use multiple techniques in order to repair the meniscus as one would in, say, a bucket-handle tear where you use multiple all-inside sutures such as a Fast-Fix, and then also using inside-out sutures in the mid-body substance. For the anterior instability, the inside-out traction sutures can also be helpful in reducing the meniscus, and in the PRISM group, we have noted that repairing the anterior instability can be performed well by placing anchors in the anterior tibia and then passing them around the anterior instability using inside-out traction sutures. Okay, I'm going to move on to discoid medial meniscus. The discoid medial meniscus is a rare entity, and it is not seen very often, even in pediatric sports medicine clinics. As part of the PRISM research interest group, we performed a multi-center case series of our discoid medial meniscuses, and these are the following findings. From a group of eight hospitals, there was a total of 21 patients, 9 female and 12 male, with 22 discoid medial menisci. The mean age at the time of diagnosis was approximately 12.8 years, and the most common symptoms, similar to a lateral discoid meniscus, were locking or clunking, which was present in over 50% of patients. Amongst these, a total of 12 discoid medial menisci were complete, or 55%, 8 were incomplete, around 36%, and 2 were indeterminate. Amongst the discoid medial meniscuses, tears were present in a total of 13 knees. Within these, the most common type of tear was a horizontal cleavage tear, with approximately 54% of the meniscuses having a horizontal cleavage tear. Of these, 5 discoid medial menisci were unstable, representing 23%, and the medial time from initial diagnosis to treatment of these was 13 months. Of these, all of them underwent arthroscopic saucerization, and of the 13 torn menisci, 7 were repaired. The median follow-up of these patients was approximately 24 months, and of these, 4 underwent reoperation. All knees which required reoperation had undergone repair for a posteriorly located tear, and there was a significant association between operative repair and the need for operation. The reoperation rate by tear type, tear location, and treatment is seen here in this chart. Thank you, that's the end of my presentation. If you have any questions for me, this is my email, bhas, h-a-u-s, at ucdavis.edu, and thank you for listening to my talk. I'll let Julie know about the insert video was was the thing. We just said all one bit all one recording. You're going to have to cut out like the middle part. Does someone know how to do that? I'm going to try. I think I just looked it up on the Internet and found out how to do it. Well, let's do it. OK, I'll do it with you. Alright, that way I'd have to be downstairs though, so we'll see. We should get upstairs and do it then. See. Timely, they're just talking until 4. Yeah, schedule. I've done video editing before, but I think when I just easy to like cut it this way, I think it's hard to cut out a middle part. I don't know how you do that. See, unless someone else hears about it, just go down. I'm going to see if she knows, but we can. It does. I mean, I think there's a forward, but I just don't know why the video wasn't clean on my end. I was picking it up. Yeah, it appeared. I heard you and everything and then it was like, started off. You would think that it would pick up. Yeah. Clearly, I know. So that was my idea. What is the only way to figure out how to make it work? Yeah. Okay, so what we did was. You played the video while Nora was at death. While we did MS team, but then when I played the video, she could see it, but you couldn't hear the actual. Oh, okay. Couldn't hear the sound video, even though I could hear it clearly fine from my computer. So, what we're so when I went ahead and did the whole recording, the issue is that the video is in the middle and so we need someone to take the recording. I just did and like, about the video, I don't care to bring the 2 together and put the video somewhere. I have a link to the video. They do that. Okay. Yeah. So, wait, but you want to put them in the drive box and then I'll download it and I'll send it to them. Well, I'm sure. Yeah, I mean, I'm sure. Let me, let me show you the link. Yes, or. Yeah, I think so. Brian, I'll stay a little longer. I believe that. Yeah. Silence on that. I went over there the other day after she said, how are we going tomorrow? Yeah, this is the name of that. Right? And then if you go to this, that's right here. Wait. Scroll down. Okay, so I downloaded that. Yeah. Yeah. It was not this good. Yeah, it's snowing. I wish. At $1, I don't know. Probably there's nothing that she's out somewhere. That's right. It's annoying. Yeah. She gets to that nobody else gets to don't don't tell me what needs to be done. I know what needs to be done. I just need someone to do it. Yeah. Right. Sorry, yeah. He has just arrived. He has arrived. He's not an extra yet. So let me get that. That's right. And I will, are you available? Just text me and I'll call you back. I have, like, there's other lectures I need to go back and listen to. Just text me and I'll call you back and then. Chad from our correct without about Riley. Yeah. In the game, he, he, he is he got the graph. Yeah, yeah. Yes, thank you. So many patients that I ignored and kind of pushed them along, and they just did get better with it. And I'm not going to say this is my fault. It's usually one of the things that I feel like I've had the most impact on my patients. Something that's fairly simple to do. It's become an easy procedure, especially with the transformation of the MCL. And it's a very simple procedure. It's become an easy procedure, especially with the transformation of the MCL. And it's a very simple procedure. So there's minimal data to say that we have to do it, because again, they've been living in Verus forever. So if your root repair doesn't change the Verus, and if you do a good repair, ideally they go back to living in Verus, but with a now a healed root. But I'm aggressive and I do the osteotomy, I love osteotomies. So that's also my bias, but five degrees or more for me is an osteotomy. Opening wedge or closing wedge? Great question. So my experience is medial opening wedge, but I've been moving closer and closer to converting to a distal femoral closing wedge, just so they can wait there and it's a more stable construct. But my training, I'm decent at medial opening wedge, and I just don't have the experience on the tibia, but I have the experience on the femur with the closing wedge. So that's a tool that's growing in my toolbox as I get a little bit more confident with that. I'd say not very often for the osteotomies, but sometimes it's clear that there's just too much load on that medial side. And I think that we're going to be using osteotomies a lot more than we used to. If you look at the full spectrum of meniscus tears, the minor repairs are going to have to be unloaded at times where I predict for the future. So I think osteotomies are going to continue to grow in number. But for the root tears, I have to say, I haven't done a lot of them. I don't see enough patients with significant enough there as to really, at least in my practice, move to an osteotomy. And I will say, I have a very healthy fear of osteotomy in the obese patients. Certainly, I did one on a patient who had a various thrust and had a post-traumatic corner injury. And it was a lot of sweating and watching, waiting for this thing to heal, and that's why I asked about closing wedge, because we did a lot of closing wedge osteotomies when I was a resident, but not something that I felt comfortable doing, lateral closing wedge on the tibia. I felt comfortable doing it, did one that's the proximal tibia joint, but in these patients, I would feel much more comfortable closing that down, putting the plate on, and I think being able to do the meniscal root probably a little bit easier with the closing wedge. But I have a very healthy fear of the osteotomy in the obese patient, because if that fails, that's a disaster. If your medial meniscus root fails, it is what it is. And so I look at osteotomies in those patients the same way that I look at knee replacements in my joint colleagues, that we have to lose weight before we can go that route. I think, you know, it's certainly a solved problem, right? I would say now, so nowadays I'm doing my osteotomies using PSI, so patient-specific instrumentation. I don't know if we have any of those companies here, but if not, we should get them here for the next course. But when you do it using, and there's several different companies, but you can ask the company on the HTO or VFO guide, in this case the HTO, to make a, to add an extra socket for your root. And so based on the CT scan, they can put a little slot, a three millimeter or 4.5 or whatever size tunnel you want to drill for your root, or two tunnels if you want it. They can build a slot into the guide, and all you do is drill your pin out, and based on the 3D planning with the CT scan, it goes to the anatomic medial root. And so then all the cost of using a root guide by any company, which can be tough in these tight bare skis, goes away, because you don't have to use a guide, because it's built into the HTO guide. So there's some advantages in terms of our ability to accomplish these tasks a little bit easier, whether it's opening or closing wedge. Do you have an upper age limit for your company? I know there's a high food care enrollment in the department, but on that issue, the base is over 65, over 70. So, you know, they asked if it's part of the status. The same question for the food response, HTO. Do you have an upper age limit for these cases, roots and HTOs? So I'd say for your patient, do it. You know, they've got good cartilage, they're well aligned, stable knee, acute incident, no reason not to do a guide. Not a lot, but there's some very happy 72, 73-year-olds who've had root repairs. And if you've got all those things in place, then the age is just a little bit. Fix those, because, you know, if you don't, you know, you're going to be sending them to your office. I would agree. I mean, I'm biased in Colorado now, which is different from where I trained in Chicago, but people ski in their 70s and 80s, and they don't want to stop. So I think it's a big discussion, though, with the patient, because I do put them on crutches for six weeks. And I also tell them, look, at this age, even if I get a great repair, it may not heal. You know, the blood supply is not great. It will augment, but it may not work. And if it doesn't work, I put them on crutches for six weeks. At that age, even if they're healthy and physiologically young, they're going to deteriorate a little bit. They're going to atrophy. Both legs are going to atrophy. That's going to take a hit on their body. So that's a long discussion for me, but I don't let age be the cutoff. But it's a much longer discussion about the potential downsides. Yeah, I agree. I think that the cartilage age, the physiological age, that's just mentioned, I think those are the drivers of that decision. You've got an older patient, their cartilage age is 30 years younger than their physiological age. I think everybody's pulling that. I do think, Eric, one of the things that I think the older people get, though, the rehab is harder. I think younger people recover quicker. They need less therapy, less time. And so having that discussion with family that, you know, this is a four-month, six-month, you really ought to be committed to a rehab process for a couple minutes. That's the whole comment about aging. I think they do rehab slower even if their cartilage is in great shape. You guys all have in mind in terms of your rehab after, say, a root repair, what are you doing for your roots? So six weeks of limited weight-bearing. I let them go put flat. I just think it's torture to go strictly non-weight-bearing. I would say half are compliant. The big individuals are not compliant at all. I use a big T-ROM knee brace. And, again, usually when they have these conical thighs, which so many times these root repairs do, they're not wearing those. I try to say, you know, no weight-bearing flexion beyond 90 degrees for three months. But, again, the compliance level when they come back, I think, has been seen as close to zero. And so, you know, that's what I tell them. That's what's on my protocol. But what they follow, I honestly couldn't tell you. It's a different beast in Colorado because they, especially my older patients, they have to do their workouts 50,000 times a day and surgery and recovery cannot interrupt that. I think we see something similar to that in California. But the last two years have gone to four weeks of non-weight-bearing if they can, touchdown if they can. I think that our constructs are stronger, and I certainly haven't had problems with that. I don't know how low we can go. But, you know, for root repairs that come together nicely, acute cares that are good solid construct and repair, I think four weeks is okay. A motor brace. I use a lung motor brace a lot. And if I have a patient who says to me, you know, I can't do the surgery immediately, I think we used to think of roots as an absolute emergency, you know, get it done immediately. But I think you can probably, you know, it's, it's, it's clear you can wait a little bit. And I put those patients in a motor braces too. And I use them a lot for post-op. I think like the quality of the surgery material, I think a lot of our therapy goals are what I call aspirational. You know, we have cones of shame. We can put her on dogs that will chew her incisions. We don't have cones of shame to stop our patients from doing full weight bearing. A lot of my patients are in their 30s, most of them are, and it's really hard to limit their weight bearing more than recovery room. Because I've seen these kids out in the parking lot after surgery sometimes and they're full weight bearing despite our recommendation. So I think the quality of fixation, if you're going to, if you think you want to put another suture in, probably put another suture in, I think your patient's probably going to stress it. The other thing I'm doing now with roots, I started doing this for about eight months, is centralizing them on the medial side. So Erin Critch has described this as, as blood and others, but you can do it arthroscopically now. And I think from a rehab perspective, potentially getting one or two or even three anchors, depending on how extruded that root, that meniscus is to begin with. You, you are almost load sharing your group repair with the centralization anchors. We don't know in terms of the long-term data on that yet, but the short-term data looks promising. So technically we could certainly try in the lab if anyone's not seen that or wants to try it out. But more to come on that, but that might help us. So, I think that, look at the tibia.

discoid meniscus

management

Brian Haas

PRISM Meniscus Research Interest Group

diagnostic imaging

saucerization

repair

arthroscopic discoid meniscus classification system