Okay. All right. Hello, everybody. This is Lee Pace. I'm in Connecticut, and I'm going to talk today about all the different types of meniscus repair, all inside, inside out, and outside in. Okay. These are my disclosures. Okay. I do need to give a shout out to our course chair, our course co-chair, Aaron Critch. He has talked about this and published on this a couple times now about meniscus repair principles. I think it's important to note anytime we're discussing meniscus repair that ABCs, anatomic reduction, biologic augmentation, and circumferential compression are the three tenets for any successful meniscus repair. It's very important that we lock out that synovial fluid so that we can get some good healing tissue. You can see that demonstrated in a couple of different techniques here. Okay. We have typically looked at meniscus repair via three different techniques, and that's obviously excluding root tears, but we've typically described the techniques as being all inside, inside out, and outside in. Those are correct descriptions of those repair techniques, but I would like to also offer in another way or an additional way to think about meniscus repair, and that's via these two classifications here, having a meniscus repair that's performed as a capsular-based repair or a meniscal-based repair. Capsular-based repair is detailed in this little graphic, is fixation that is based on the capsule. You can see here's the meniscus, and then here's two little fixation points on the capsule. That's a capsular-based repair, and then here is meniscal-based repair where you've got suture that is fully contained within the meniscus, and typically you've got a knot tied as the anchor point. This is all meniscal-based fixation. Here's a couple examples here down below of capsular-based versus meniscal-based fixation, and that can have some implications primarily on the lateral side, but it is an important distinction to make in addition to the other repair techniques. Now, when to do a specific technique? That's a big part of this talk. What are the considerations for a specific technique? There's several things that we need to look at. Obviously, location is important. Is it in the posterior horn, body, or anterior horn? For me, and maybe not for everybody, but at least for me, one of my considerations is medial versus lateral meniscus, and then obviously, tear type. What type of tear is it? Different tears call for different techniques. Let's look at this a little bit closer here. There are some positional indications here. As we alluded to earlier, the location of the meniscus, so if we have a posterior horn or body tear, we're typically looking at some type of all-inside or inside-out repair technique. The anterior horn, and sometimes the body, can be fixed in an outside-in, but usually, outside-in is used for the anterior horn. Then also, the location within the meniscus. Is it at the meniscal capsular junction? Is it in the red-red zone, or is it maybe in the red-white junction? Meniscal capsular junction tears, I usually will be fixing that with a capsular-based technique, either all-inside or inside-out capsular-based. Red-red zone, usually the same thing, at least on the medial side. Then further in, it doesn't matter if it's on the medial or lateral meniscus. If it's at a red-white junction, if it looks amenable, I am usually leaning more towards a meniscal-based repair technique for those type of tears, or I should say tears in those locations. Then again, as I alluded to earlier, medial versus lateral. On the medial meniscus, in the posterior horn or body, based on where that tear is located, again, I'm using either capsular versus meniscal-based, and again, that's going to be either all-inside or inside-out. Then anterior horn is almost always going to be an outside-in capsular-based repair technique. On the lateral meniscus, in the posterior horn in particular, this is where I spend a lot of time, especially with meniscus tears in association with an ACL injury. I am almost exclusively meniscal-based, like that posterior horn lateral meniscus. It's got a little bit of extra translation to it, and I think a meniscal-based repair provides a superior reduction and also preserves that native meniscal translation, whereas I think a capsular-based repair tends to almost extrude it posterior in the joint, and it also tends to crinkle it up a little bit. For me, the lateral meniscus posterior horn is almost 100% meniscal-based. Once we get into the body, I think that there's some more leeway there, and there's probably more opportunity for a capsular-based repair there. Then obviously, on the anterior horn again, it's going to be a capsular-based repair, typically an outside-in type repair technique. Now, let's go through a few different tear types, some specific examples here. This is looking at a medial meniscus in the posterior horn. This is a far peripheral undersurface vertical tear near the capsule. This to me is a perfect indication for some sort of all-inside capsular-based repair. Now, this is a little bit different tear. This is a little bit more of a complex posterior horn medial meniscus tear. This has two separate tears in it. A tear like this or a bucket handle tear, I am usually opting for an inside-out repair, something where I can place multiple fixation points with a very small footprint is typically how I'm fixing these because I think that these things, in general, more is better for these more complex tear types. Something small that you can do with an inside-out capsular-based repair technique. Horizontal cleavage, I know a lot of people like to use some sort of all-inside capsular-based repair, but I'm going to pause it to you guys. I think that doing a meniscal-based hay bale stitch is the best way to fix these. I'm going to have a video of this a little bit later, but I think this is really the way to go for these horizontal cleavage tears. Then our last example here is with a radial tear, and then Pat Smith and Aaron and the other folks at the Mayo Clinic have recently described, or I should say, I don't know if I want to say described, but at least categorized in a slightly different fashion, these sort of complex tears near the posterior root of the lateral meniscus, these lateral meniscal oblique radial tears. These I often will fix in a meniscal-based technique as well, but sometimes these will require a hybrid technique. I may be doing, for a complex radial tear, it may require a meniscal-based as well as an inside-out capsular-based technique to really bring that thing together. Sometimes you're using more than one technique, and these are examples of some of those tear types that I often will use more than one technique. Let's go over each repair technique now. Inside-out, I've put inside-out and outside-in together because the principles are basically the same. It's just a little bit different location, but the advantages of these techniques is they're still considered the gold standard. They've got good strength. They do give you good compression across the tear site, and they do give you, as I alluded to earlier, greater flexibility in repairing certain complex tears. The needles that are used that have the suture attached to them are typically quite small, so it's small perforations on the meniscus, and it does give very good primary stability. The disadvantages, particularly for an inside-out repair, is that it does need an assistant. There's potential for neurovascular injury, and obviously, if you're having to make a posterior incision, that creates more dissection and pain, which could lead to arthrofibrosis. It is obviously more time-consuming, and there are definitely some issues with potential imprecise needle passage to the back of the knee, which I will go over a little bit with the point of sharing some information that I think will be helpful to minimize imprecise needle passage. Technique articles. The posterior medial and posterolateral approaches are rather well described for inside-out repair, and these are two examples of some technique articles that are available that describe both sides. I'll make a quick comment about the lateral approach. There is some debate about splitting the IT band or going between the iliotibial band and the biceps femoris. In my experience, what I have done is I will just find the joint line, and I will incise that structure or collection of structures at the joint line. Some people, it may be through the IT band. Other people, it's going to be at that junction between the biceps femoris and the IT band. I think if you just find the joint line and center your approach there, wherever that happens to be, that's going to be the recipe for success on the lateral side. Now, we actually just published this earlier this year. This is a modified approach to inside-out medial meniscus repair, and I can't take credit for this. I'm just a messenger. I have Matt Matava to thank for teaching me this, but the classic approach for inside-out medial meniscus repair is to get down to the back of the knee and then develop the interval anterior to the gastrocnemius tendon and above the semimembranosus. We have this shown here. This is a cadaver, so this is not the typical incision size. In fact, mine's typically much, much smaller than this, but what we've got here in this upper left video, or upper left picture, excuse me, this yellow line is the joint line. This is the medial joint line. You can see the semimembranosus dissected out here. The gastrocnemius is here. You can see this is the interval that one would typically go into to place a scoop to catch needles. Now, the problem is this. When you're doing this dissection, the knee is typically flexed close to 90 degrees, but when you pass needles, the knee starts getting more extended. It's not typically flexed more than about 30 or 45 degrees, and what happens is in extension, the semimembranosus becomes much more parallel to the joint line, and then what it does is it deflects your scoop proximally, so you actually have a really hard time having the scoop low enough to catch your needles, and you can't see anything, so I think that probably plays more into the imprecise needle passage through the back of the knee than the needles going in different directions. I think that our scoop in a lot of situations may not be in the right spot, so what you do instead is you still develop the plane anterior to the gastrocnemius tendon, but you come below the semimembranosus. That way, when the knee comes into extension, that scoop is not deflected proximally, and you're right at the joint line, and you can catch your needles very easily, and I've got a video of it right here. So, we've got the scoop in place. You can see the incision. Now, watch where this needle comes out effortlessly right in the middle. Boom, right into the scoop. You can see it perfectly well. My assistant has a very easy time of grabbing that needle. This is a game changer for inside-out repair, and I think it has made my life so much easier in doing this, such that I don't worry about doing inside-out repair. It's just another thing that I do for the right tear types, okay? And here's an example of, I showed this picture earlier, but this is a complex medial meniscus tear, posterior horn with two different sites of a tear in it. So this is something that I'm going to use an inside out repair on, because I want multiple spots of fixation. And you can see here how I've stacked these things up to incorporate both tears into this. And again, these are placed about three to five millimeters apart, but can be placed very, very closely. And that's what you want to do. I mean, this is probably, you know, 12 or 13 stitches. If you count the ones you can see, plus the ones that are underneath the meniscus. You want to do a double stack vertical mattress. You want to lock out synovial fluid above and below the tear. Okay. Here's an example of an anterior horn repair. I will typically use a spinal needle, and then there are commercially available, flexible suture passing devices that can fit through the spinal needle that can then be retrieved and loaded with sutures or use that to shuttle the sutures back and forth. But again, you can see these vertical mattress stitches here, and then you can still effectively get below the meniscus to place stitches in a similar configuration there as well. That requires a little bit of practice to get used to that because sometimes it's a little blind, but it's a very doable technique, especially in the anterior aspect of the knee. Okay. So all inside capsule base. We'll talk about this now. This is probably the most commonly used technique in meniscus repair today. And these are all the commercially available devices that are out there. And a lot of the nuance of this technique is based on the specific device. So in an effort to be free of any sort of commercial bias, we won't really be able to talk about, it's hard to talk about nuance for these things in detail because a lot of it's based on the specific implement that you're using. But with that said, the advantages of this is it's quick, less assistance, or maybe no assistance needed, no extra incision, so therefore less pain. And it's got great primary stability. And I personally consider it great for the medial meniscus. The disadvantages are it's got, because there's an implant loaded in the needle, it's a larger board needle that's going through the meniscus. So you have less room for these implants for more complex tears, like the one I just showed. And the other issue is that most of these implants have a couple of peak anchors that deploy on the capsule. And those peak anchors, they don't always flip. And so sometimes I think what happens is they don't flip all the way. And then over time, they kind of just work their way back into the joint and you lose your fixation strength across the repair. However, there are some new implants that have anchors that are made of suture that can then deform. And I think those will probably be better. And I think that probably most of the manufacturers will start going towards that. And that will actually help this technique all the more. Okay, and here's a great example of a tear that I prefer to use an all-inside capsular-based repair device. And this is like a very simple, non-bucket posterior horn medial meniscus tear that you can see here. And I do believe I've already fenestrated the MCL to gain access. I didn't build the slide out about this, but if you can't see, you can't fix these things. On the medial side, if you can't see the tear, do a percutaneous fenestration of the MCL at the femoral origin with a spinal needle. Get the access that you need. These things heal. The MCLs, I should say, heal. There's actually now a couple of papers which have shown that. Mark Miller recently published on that, as well as, I believe, a Korean group has published on that. But I could be wrong about exactly where, but there's two papers. Okay, and here's this tear now being repaired. And again, it follows the same patterns. You need fixation on the superior and inferior aspect of the meniscus. So one of the issues that I've run into with these capsular-based devices is when you try to place the sutures on the undersurface, there's a lot of skiving that occurs. So the needle will skive, skive, skive. And if you look at my little diagram I've got here, this is a meniscus, here's the tear. You know, it's easy to come and place anchors above into the capsule and then on the superior surface. But coming underneath, it's really difficult to get the needle to enter in here and penetrate the meniscus and then take a second capsular pass. What usually happens is the needle skives, skives, skives, and then kind of makes its way up like this. And you get this very small bridge between where the needle penetrated and the tear. And what happens is sometimes that just pulls through and you actually haven't fixated the tear properly. So this is a little technique that I do where I will actually poke through the meniscus from superior to inferior here towards the inner free edge. And then being underneath the meniscus, sort of drag that thing along and poke through the capsule there and then come and take a second pass up top. And that gives me fixation above and below the meniscus to lock out the synovial fluid. So you can see the sutures underneath the meniscus there. And that's a really nice repair that we're able to achieve with four suture anchors there. Okay, and then here's a video of a undersurface tear. So not quite complete, but you can see the tear is right here. And so I'm gonna do the same thing where I place the first anchor. I go from top to bottom, skive along the tibial plateau. Skive might not be the right word, but move along the tibial plateau without injuring the cartilage. Place this anchor into the capsule here and then come on the superior surface and place my second anchor. So there you can see me sort of sizing things up. There I am sort of poking through the superior surface. And then I can see myself. Now I'm underneath the meniscus, able to poke through the capsule. I know I'm in a good spot. Deploy the first anchor. And then I know I'm checking. I can see my sutures are where I want them to be. I achieved what I wanted to achieve. Place the second anchor and then tension it down. So that's a really nice way to not have that issue with skiving and get yourself broad compression with these all inside repair devices. Okay. So now we'll finish up talking about all inside meniscal based repair. Okay. So the advantages are seen chiefly on the lateral meniscus where you can maintain normal meniscal translation while still attaining anatomic reduction. A single stitch can achieve 360 compression. Again, you avoid posterior dissection and it's also great for radial tears and horizontal cleavage tears. And in these situations, it's actually got superior biomechanics to some sort of capsule based device. The disadvantages is the knot tying can be consuming and you are unable to get far peripheral tears and a tight joint definitely can be challenging. Okay. But again, here's some examples. Again, longitudinal tears. Well, excuse me. I'm gonna start that one over. Okay. Okay. So there are several examples of different types of tears that are fixed with the meniscal based repair technique. Probably the most common one is a longitudinal tear in the posterior horn lateral meniscus seen commonly in association with an ACL tear. You can get circumferential compression with that thing. And I'll show an example, but it's also again, really good for these horizontal cleavage tears. As you can see here with these 360 Havel stitches, and that just takes one pass through the meniscus and then you just tie it. That's actually not that time consuming to do that. You might wanna edit that little thing out right there. Okay. And then radial tears. Again, the biomechanics favor meniscal based repair for radial tears. And this simple one on the upper, on the right hand side, you can see two side to side stitches. I can get that repaired all the way out to the inner free edge. Okay. And then this lower left, you can see this more complex stellate that's this Elmore tear pattern. And I'm able to bring those two ends together and achieve a much more anatomic reduction and restore the hoop stresses much, much better than if I tried to do something capsular based, which is again, just gonna push the meniscus back and not really help restore the cushion effect that we want the meniscus to have. Okay. And then not to spend too much time on the literature, but this is a study showing, looking at radial tears and with a meniscal based repair construct versus a capsular based repair construct. And basically any variety of meniscal based repair construct, even just a simple one was stronger than the inside out capsular based repair construct. So again, I think the biomechanics favor this for radial tears. Okay. And again, this is an example here of the most common tear type that you'll see that I fix with a meniscal based repair technique. This is the vertical tear post your horn while meniscus is seen here. And then you can see that, passing some sutures with one of these devices, then you can see afterwards what it looks like. And then I can tell you that these knots, they're small, this is 2-0 suture. So it gets mushed down into the meniscus. And a lot of times these knots actually, you can't even see them on second look arthroscopy. So they're not scuffing the cartilage, which is a very reasonable concern, but empirically hasn't played out. I think this is different from the shoulder because the shoulder is not a weight bearing joint. It's much bigger suture that can scuff the cuff, but in the condyles in a knee with a smaller suture that's weight bearing, these things get compressed into the meniscus and don't cause scuffing of the femoral condyle. Okay. And then here's some videos of some tear types that I've actually been able to fix that I would typically have fixed with another technique, but was amenable in this situation to meniscal based repair. So this is actually a bucket handle, medial meniscus tear that I fixed with an all inside meniscal based device. The tear was in enough that I had a cuff of tissue that I could grab into peripherally. So you can see here that I'm gonna pass the suture peripheral. You can see the little needle come up and there's the suture. And then I'm going to check and I stick a probe in there and I can see that I'm on the far side of the tear. And then I'm advancing. There's another suture pass there. And then here is the inner suture pass there. So you can see as I tie that together, I'm gonna get 360 compression. You can see this. Now I was able to get fixation above and below the meniscus using this meniscal based device. This specific bucket handle was amenable to it. So I didn't have to make an incision, use less suture and this healed beautifully. This patient did great. So it's amazing what you can use this stuff for. Okay. And then here is a discordant meniscus that had intrasubstance degeneration, AKA horizontal cleavage, that I use this device or this technique for repairing this in a hay bale fashion. You'll see this here in this video. So again, this requires just a single pass, pass your suture through and then just tie some knots. And it's fantastic fixation as it comes down, which you can see here. And then you can see, I'll pass another one here. Again, I usually try and put the device next to the last suture and that sort of spaces them appropriately. And then ultimately I placed four that you can see here. And again, that provides the compression of the tear without further extruding it towards the capsule. And it's less cut through on the meniscus with this sort of repair construct that's completely contained within it. Okay. All right. So in conclusion, you gotta be adept. I hope I've been able to highlight what's possible with meniscus repair, if you are aware and have spent the time to become capable with these different types of techniques. A good meniscus surgeon has several tricks because you're gonna run across a meniscus tear that is not like the others, that's gonna require you to think on your feet and do something that's a little atypical. And you wanna be comfortable with all these different techniques so that you can do that for those patients. For me, when deciding between inside out, all inside, outside in, meniscal based, capsular based, et cetera, there are several factors to consider. Medial versus lateral meniscus tear, specifically for me, maybe not for everybody. Peripheral versus interlocation, posterior versus anterior, and obviously tear pattern. Thank you guys very much.

meniscus repair

anatomic reduction

biologic augmentation

capsular-based repair

tear location

surgical techniques