Name: New Options for Anatomic Socket Creation in ACL Surgery
Uploaded: 2016-03-31T00:00:00Z
Channel: Arthrex

Not Hidden

English  - en

video

VPT1-00635-EN | B | New Options for Anatomic Socket Creation in ACL Surgery

Asheesh Bedi

Human

Presentation Videos

New Options for Anatomic Socket Creation in ACL Surgery

I think Doctor Cordasco just said it best in his talk, which is how good are we maybe really at ACL reconstruction? And I think all of us would agree that for different things that we do in sports medicine, it's a very effective operation. But one of the things that this company does very well is always ask the question of what can we do better? And I think if you look at the failure rate of these surgeries, it all depends on what you consider to be failure. Maybe it's only 5 to 10% of structural failure, but it all depends on how we define it. So if there's recurrent instability in the setting of an intact graft, is that really satisfactory for the patient? If they don't get back to their previous level of sport and have to give up certain activities because of some residual or subtle instability, is that success? And then certainly with all the focus on that we're talking about here at this meeting in Bio-Post and considering joint preservation with meniscus loss and cartilage injury that happens after a reconstruction, is that a success? So I think all good questions for us to be thinking about of what we can do. All of us recognize this concept, which is when we do an ACL surgery and something doesn't go right. And we've learned from techniques. The most common reason has been technical error and it reflects this socket malposition. Again, initially maybe from a lack of appreciation of the anatomy, maybe secondarily from a lack of appreciation of perfect techniques. So many of us have seen these these reconstructions which offer rotational instability despite AP stability on a Lachman exam. But I think it's humbling to recognize that this doesn't just reflect low volume surgery. Even high volume surgeons can make this mistake and just make it repeatedly. And in fact, a recent study actually suggested that academic hospitals may do may do no better. And I think this is the key for us to recognize that the importance of the anatomy largely again, credit to many of our our colleagues, Doctor Clancy, Doctor Fu and others that have identified the footprints, that there can be this vertical graft configuration, but I think it helps to step back to recognize that we're not graded on our X-rays. We are graded on the outcome for the patient. And ultimately we're looking to restore stability for the knee. They come complaining of this pivot shift which is the subluxation of the femur and the tibia. And that's really our goal. And because all of these pivot shifts are different, what we may need is different. This is just a good video borrowed from Charlie Brown that I think is instructive. No. Two of these pivot shifts are the same. And as I know, Doctor Henry and others will talk about here in this next session. Some of these need different approaches than others, and that may be a role for our all or InternalBrace or other reconstructive procedures. The footprint anatomy, I think, has helped us in terms of revisiting anatomy and then designing tools to to reproduce anatomy. We recognize this sort of bundle configuration, but I think the key here is to recognize this relationship in which fibers have some tension throughout a range of motion. And this is very difficult for us to achieve with tunnels and a single tube of collagen. And again, this, I think, leaves potential for us to continue to improve beyond just considering the anatomy. Well, why is that potentially important? I think we recognize when we look at reconstruction techniques, they have evolved over time. The two incision technique was independent drilling but potentially had some morbidities associated with the approach, but with still good surgery along the way, we went to Transtibial reconstruction, which can be effective but also has some pitfalls in terms of confounding and error on the tibia to then resulting in a secondary error on the femur. As we recognize here, medial portal techniques, or anteromedial drilling has allowed us to better approximate that anatomy more reproducibly without the second incision. We now, with Arthrex help, have some other approaches, including flexible technology, which I'll talk about, and then retrograde or FlipCutter technology, which has really improved and given us many facile approaches to still reproduce anatomy with variable trajectories. And one question may be does that trajectory matter at all? I do want to emphasize and be careful about saying that transtibial surgery is bad. I don't think that it's bad, and it can be done very well. There's a number of papers that have talked about using a good tibial tunnel technique to allow you to approximate the center of the femoral footprint and capture footprint fibers, but I think we have to be careful. It requires a very well placed tunnel and sometimes it can lead us to some pitfalls. These are some studies that have pointed this out. When you look at a trans tibial graft, even well done. Compared to the native graft on sagittal, coronal and axial planes, we don't often reproduce the obliquity as well as we would would like. And even when we are able to reproduce the anatomy and Aeperl and others have published this, which is to get to the right spot on the femur, often requires a relatively posteriorly placed tibial tunnel that results in this so-called posterolateral to anteromedial mismatch. And you can appreciate compared to a center, center, or anteromedial type reconstruction. This results in a loss of obliquity and rotational stability in all planes. When I was a fellow, we looked at this a little bit with Dave Walczak and looking at this tunnel expansion, which has often been thought to be a biologic phenomenon, that the graft has a bungee cord or windshield wiper effect. But I do think we appreciate what the trans tibial technique. There's the risk that the plane is placed somewhat eccentrically in order to approximate the femoral footprint. There's an iatrogenic re reaming when you pass the reamer through the tibia a second time, through that soft tibial bone. And the end result is actually time zero expansion, where the aperture of your tunnel is larger the day you put it in. Marc Steiner did this study, which has also helped us to to to recognize this, that if you connect the center of your footprint on the tibia and the femur with a single line, it results in a very unique trajectory, a very short and proximal tibial tunnel. And I think none of us would really drill this this way because of the risk of subchondral compromise and graft tunnel mismatch. And again, a number of studies have corroborated the importance of potentially independent drilling to minimize this complicating or confounding error. This was work done by Lou Frey and the group out of Duke, showing that in general, when you use an independent flip cutting technique, the ability to approximate the footprint and restore anatomy in vivo was better. And again, this correlated with better stability compared to a trans tibial technique. Well then you would ask the question if independent drilling is the answer and we've solved that with these new tools, then where is there room to be better. And this is kind of some of that humbling data that suggests there's more to more to learn. This is recent paper from a Danish registry that shows even when we used an independent drilling technique compared to a transtibial technique that was actually, paradoxically, at least at an early time point, a higher failure rate. So the question must be asked why? Is it because these graphs are actually functioning better and may be seeing more load, and that these transtibial grafts weren't doing anything, so they weren't failing? Or is it, in fact, that we have to consider some other things that we can continue to improve on? This is a slide from Aaron Critch, who I know is going to present soon, talking about isometry and strain patterns in the graft. And you can see when you look at these different graft configurations, they are different. And it begs the question that maybe we need to consider some of the other properties now that we understand the importance of restoring anatomy. We're looking at this a little bit at Michigan by looking at regional strain patterns in the graph. This is a technique where you can use a fleck pattern and look at strain patterns to appreciate where failures occur with cyclic loading. And we've combined that with a finite element model. Here you can see these are two different graphs, both of which approximate the same anatomic footprint on the femur. But does it make a difference if that tunnel is very oblique and drilled at 20 degrees, versus drilled with less obliquity at 40 degrees? Does that affect the mechanical properties of the graft? Well, I think this is where the innovation of this company is great because new tools can help to take those factors into account. We can prioritize the anatomy, but we can also pay attention to isometry and to mechanical graft properties. So the FlipCutter is one of those tools that allows for that versatility. Any trajectory for primary revision surgery, and as Pat just eloquently showed us, contained blind sockets for biologic healing. And again, the medial portal technique now has some evolution, as Jake shared with the flexible technology that can avoid hyperflexion, increase tunnel length for graft tunnel healing, but also facilitate your transtibial transitioning surgeon to be familiar with positioning. These are those tools. Here I would draw your attention to the center slide at the top which shows the spade tip pin. This is very advantageous as it essentially creates the tunnel for passing your TightRope or button without a second drilling step, so it can all be done as a one step, even with a soft tissue graft. Again, the handle that allows you to really pinpoint and choose the angle of your drilling. So again, to match the obliquity of your tibial tunnel, to avoid that additional killer curve at the femur where there's potentially graft stretch and failure. And then again flexible screwdriver technology for aperture fixation if that's your fixation of choice. This is just showing that step here that that Jake talked about earlier and why this might be advantageous compared to other systems. It's the lowest profile reamer. So you can bring it in right by the condyle and directly visualize that to assure that you're not injuring the cartilage. You can also pass it right by the PCL. And again, you can see the entire time that you drill because it does not require hyperflexion, which can bring the fat pad into view as you move forward. Here you can see this is kind of the end result of the tunnel that you can get there. Again, anatomically captured, again entirely done at 90 degrees of flexion. I can work very well for BTB or hamstring or soft tissue grafts. But again the key here is it doesn't just prioritize the anatomy but allows you to you to customize the obliquity of your tunnel to avoid that additional turn or angle in your graft. Doctor Cordasco already very eloquently demonstrated the FlipCutter technique, so I don't need to review that for the all epiphyseal technique, which is remarkably valuable in that population. But I would highlight the importance of this technique for revision surgery. As all of us are seeing more and more failures, we recognize the need to navigate around enlarged and previously placed tunnels, the hardest of which are tunnels that are partially in the right place but also partially expanded. You can see the challenge of this in a partially right tunnel with a previously placed interference screw. You would need to remove this to perform a conventional independent medial portal technique, creating a void and also potential for coalescence in the previous tunnel. Here we use the FlipCutter technique and introduce a precise tunnel. There again, to a half millimeter size can leave the screw in place because of the unique trajectory, and then don't have an issue in shuttling in a new graft and performing a revision reconstruction in a single stage technique versus staged and grafting. I think the important things is what are we are we finding? Well, with this technique, which allows us to prioritize both the footprint and the obliquity, we have something that looks a lot more like the native ACL versus our previous transtibial techniques. And again, I would combine this, I think, with biology, to recognize that we can augment repairs in the simple setting of a revision surgery, where we can drill independent tunnels when they're grossly placed, as here, things are easy. But as we're encountering more of these cases where we have reasonably well done tunnels and need to navigate around hardware or partially expanded tunnels, or now combined with associated secondary ligament instabilities, or even in cases of malunion. Again, the tools iBalance and others can help us to get there, but also replace these sockets in a standard way. I'd also mention don't hesitate to stage if these are expanded tunnels to which we we can't work, particularly in a, for example, a previous double bundle reconstruction. Don't hesitate to remove things. Graph things come back another day. This is one case I did that here for, in which they were large expanded tunnels that were partially correct. You can come back again with a FlipCutter or with a flexible reamer and drill native tunnels like no one has been there. I'll summarize by just the final key points, which are sometimes these partially right cases. This is a patient who had a previous ACL reconstruction with some instability. I think you can appreciate here the graft is structurally intact. But this is a functional failure in which there's residual instability. We can appreciate this subtle posterolateral to anteromedial mismatch in the posterior tibial tunnel. Again maybe not a failure. But if you grade yourself a little bit more harshly there's start of early chondral damage and associated meniscal injury. And here when you sculpt this patient you appreciate the graft is intact. But yet there's all of this exposed femoral wall in a well-placed femoral tunnel and a relatively posteriorly placed tibial tunnel. And again, with the flexible technologies and tools, we can actually place a graft sort of on top of a graft and essentially add a bundle, so to speak, to restore anatomy and treat pathology. So in summary, I think there's lots of tools and excitement on on how to place your tunnels anatomically with lots of different techniques that that match your, your surgical practice.

Knee

Product

Low-Profile-Fräser

New Options for Anatomic Socket Creation in ACL Surgery

Verwandte Seiten

Knie

Low-Profile-Fräser

Produkt