I'm sure there's some overlap with all these presentations today. So I'm supposed to talk why NPFL reconstruction is necessary, and I think the last couple of speakers have already indicated that that's part of the armamentarium. I don't have any conflicts with this presentation. So again, as it's been pointed out already, you need to figure out what the problem is with patella-femoral joint. It's often a combined problem, so you have to figure out what's necessary. So one operation is not going to do it. You need to have an armamentarium to treat all of these problems. So you can see you've got a variety of problems in terms of just instability, instability with arthrosis and advanced arthrosis, and so you have to kind of figure out if you need to realign and you need to stabilize the patella. And then the cartilage part of it is also important, and so I think you need to figure everything out. So again, I'm talking about NPFL, but really you need a whole series of surgeries available to take care of all the pathology of the patella-femoral joint. So this is an extreme case, a 45-year-old with a chronic dislocation of the patella. You can see here, and so he's going to need a little bit more than just an NPFL reconstruction. And here you can see he's got some dysplasia, and obviously we did a release on the lateral side. You can see the graft that we put there on the lateral side, and we did a tibiotubercle osteotomy, and we did an NPFL reconstruction. Now the anatomy of the NPFL is important, as John Forkerson just discussed, so you can be very critical of this tunnel position of the NPFL here is not really very good. So I'm going to talk a little bit about that as well. But this patient did well, and you can see the patella is reduced and his knee joint functions improved. Even though the surgery wasn't ideal, I think by addressing the whole picture, I think you're much more likely to succeed than just doing part of the surgery required. So the anatomy is very important, and again, I'm not going to go through the anatomy, but I did want to point out the same thing that John Forkerson was pointing out. If you see in this diagram from LaPrade, the NPFL and the VMO, I think it's a much closer relationship than what the diagram indicates. And you can see they're almost integrated. The VMO is overlying the NPFL, and that should be part of the surgery. So when you see the surgery, you can see why it's important to identify that junction of the VMO and the layer that you're putting the NPFL reconstruction in. The NPFL is not isometric, and again, this is one study just showing that depending on which part of the NPFL you look at, if it's the superior part or the inferior part, there's some lengthening and shortening of the ligament depending on the range of motion and the degree of flexion. So again, I think it's very important where you put that attachment site on the femur to try and minimize these differences in the abnormal movement of the NPFL. So again, everybody's talked about where to put the NPFL. I think one of the questions that comes up is in open physis, and if you should put the tunnel above or below the physis. I think it's becoming a little bit clearer, but again, I think with using soft tissue surgery or just using anchors versus drill holes, I think you'll avoid damaging the physis. So here's a case of a young patient with patella instability. You can see the physis are open, and again, locating the ideal location for the femoral attachment site, and using an anchor on this side for the NPFL, and then using anchors on the patella. So you can see the two anchor holes on the patella side, and again, the anatomic location on the femoral side. Just technically speaking about the indications for NPFL reconstruction, I think it's becoming more commonplace in first-time dislocators, especially if they have an indication for surgery. So this particular case, you can see there's a loose body there or a loose fragment. I think you're likely to do early surgery. So I think if you're going to do early surgery for a first-time dislocation, I usually do an NPFL reconstruction. Again, in terms of fixation, I think using the ideal location on the femur, I use a drill hole on the femur, as you can see here, with interference screw fixation, and then I use two anchors on the patella, and again, ideal location is important. This was a patient referred with a patellar fracture, and I think we've all gotten away from drilling holes in the patella, and now just using an anchor and attaching the graft on the patellar side, I think, is much safer and will avoid fracturing the patella. Many techniques, tension on the patellar side, you fix the femoral side, and then tension on the patellar side, as you can see in these two techniques here, I tend to do it the other way, where I fix the patella and then tension on the femoral side. I find it's much easier, it's much more reliable, and I'll just show that technique. When you look at the literature, again, it's important that, you know, this is again looking at drilling holes in the patella. You can see that in the studies where there was drilling of the patella, there's a much higher fracture rate, so again, avoiding drill holes in the patella is much more important than, and just using anchors on the patellar side, I think, is a much safer technique. Here's a patient with, obviously, some patellar instability, subluxation, and we did both a tibiotubal osteotomy and NP-FEL reconstruction, and again, if you look at the literature, where you look at bony procedures combined with NP-FEL reconstruction, I'm not sure that you can delineate which is more important, and so again, doing an NP-FEL surgery at the time of the bony surgery, I think, does help the surgery. So in this particular study, this is from New York, basically showing that isolated medial patellofemoral ligament reconstruction, despite the anatomic bony parameters, was successful in these patients. So again, doing NP-FEL reconstruction is an important part of the surgery. Here's a couple of studies and reviews looking at combined procedures. Again, combining NP-FEL with a tibiotubal osteotomy does improve outcome and stability. So when you look at all the literature, I'm not going to go through all the literature, doing an NP-FEL reconstruction does not take away from the surgery. If anything, it helps with the stabilization and the outcome of the surgery in these patients. How about generalized laxity? This was from Laurie Heemstra, and basically showing that joint hypermobility did not influence outcomes, and NP-FEL reconstruction was really a significant improvement despite the hyperlaxity. So just briefly, my approach, again, acute versus chronic. So if you have to do early surgery following a patellar dislocation, I generally do an NP-FEL reconstruction at the same time as the early surgery. If there are definite underlying predisposing factors, I'll add on the bony surgery at the same time. In chronic instability, again, I think you need to assess the underlying factors. You can do an NP-FEL reconstruction alone if the underlying factors are not that significant or severe, but generally if they have significant bony abnormality, I tend to do the bony surgery at the same time as the NP-FEL reconstruction. This is the technique I use. It's a two-incision technique. I do use x-rays and fluoro to assess for tunnel placement on the femoral side. You can use it for the patellar side as well, but I don't generally use fluoro for the patellar side. I use an allograft semitendinosus doubled, and again, I tension it on the femoral side and fix it with an interference screw. And again, this is the technique. This was described by Shottell. Basically a similar technique, two incisions, fix it on the patellar side, fix it on the patellar side, and then tension it on the femoral side. So here's the surgery. This is just something we did with the fellows yesterday. Just wanted you guys to see this is a cadaveric knee. So the incision's a little bit bigger than what you need, but I just wanted to demonstrate it. But I don't go intracapsular, so I stay in extracapsular here, dissecting under the VMO. You can see here, so creating a pathway under the VMO, making an incision over the medial epicondyle, figuring out exactly where the Shottell's point is, and then putting in a guide wire, drilling a hole, and you can see the sutures pass through the femoral hole there. And now we're preparing the patella. So I usually use a ranger, prepare the proximal half of the patella, put two anchors on the proximal half of the patella. These are 3.0 anchors with two sutures on each anchor. So there's basically four sutures that are going to hold the looped end of the graft. You can see there. So we're basically going to suture each one of those sutures going through the anchor, through the graft, and basically sucking that down to the bony surface of the patella. So you create a little bony trough in the patella and bring that end of the graft sitting there. And you can see the sutures. I haven't cut them yet, and you'll see the purpose of that in a second. So we're going to pass the graft under that VMO in the tunnel. It's a three-minute surgery. It's not that complicated, but I like this technique. I think it's very reproducible, and I think you get a nice graft. So here we have the sutures, and now I'm going to suture a second layer with those same sutures with the VMO and the periosteum of the patella going through that tendon graft. So you're basically getting two layers of suture on the patellar side. So here if you're pulling, you can see the patella is coming over. It's a very secure fixation on the patella. And the two ends of the grafts are separate, so it's easy to pass them into the bony tunnel. If you suture them together, sometimes it's too big, and it's hard to get them in the hole. But one at a time, you get them into the femoral tunnel. So you can tension each one separately, get the appropriate tension, hold the knee at 30 degrees, and then put the femoral fixation in. And then I put a couple of sutures there, closing the superficial fascial layer right at the tunnel where the hole was drilled. And there's the surgery. Again, the incisions are a little bit bigger than normal. You don't need to make them that big. So thanks for your attention. I think NPFL reconstruction should be part of your surgery. applause

NPFL reconstruction

medial patellofemoral ligament

patella-femoral joint

surgical techniques

tunnel placement