This is just the beginning of revision patellofemoral surgery. I could go on and on. I think I could talk about this all day, but I say it's fixing other surgeons' mistakes and some of mine as well. I consult for Barisal and Smith & Nephew, although I'm not going to specifically talk about it. And so as far as broad categories in this talk, I'm going to talk about failed MPFLs. And as far as what can fail, they can re-dislocate, they can fracture or have significant bone loss, arthritis can develop from lateral overload if you haven't corrected that at the time of your stabilization procedure. If you over-tighten the MPFL, you can have medial subluxation, or if you over-tighten it by putting it in the wrong location, that can cause significant problems. As far as failed TTO, you can have a fracture. I've had a number of fellows call me up a year or two into practice with fractures. They can go on to non-union. You can over-medialize them, or you can under-correct them. And then very briefly at the end, failed patellofemoral replacement, they can dislocate, and there can be maltracking. And I'm not even going to get into the patients who go on to need a total knee. So as far as MPFL and re-dislocation, if you look at this picture, or these pictures, hopefully they project well up there, but you really need to think about an osteotomy in a patient that you see here on the right. So if you see a patient, and you can see this is clearly a failed MPFL who had just re-dislocated, you can see from that lateral femoral condyle edema. But if you see an MRI that looks like this pre-op, this is not a candidate for the MPFL. So it's a failure of surgery, because it's a failure of indications, and this patient, I would argue, should have had an osteotomy. If you take a look here, the femoral tunnel was far too anterior, if you look at the image on the left. And so this patient was treated with a revit, and this patient did have an osteotomy. You probably can't see it on this projection, but you can see the screw holes from the old tibial tubercle osteotomy, and they simply didn't medialize the patient enough. But again, this patient underwent ultimately both a revision MPFL and a revision osteotomy. So if you see somebody in your office who comes in and has already had a patellar stabilizing surgery, don't assume that it's a failure necessarily. It's maybe a failure just because they weren't properly corrected at the first operation. Here you see this patient. You can see they've status post MPFL, and their patella is sitting perched on a very dysplastic trochlea. So again, the alignment wasn't corrected. And so the treatment for this patient is revision MPFL and an osteotomy. And these last three are similar, but whether you do the MPFL correctly or not, if you see a patient with this type of anatomy, you're going to end up doing revision patella femoral surgery. These patients can dislocate immediately. So if you take a patient and you just automatically do a lateral release or a lateral lengthening, you are at risk of taking a patient that may have been already fairly loose and making them looser, and they can dislocate immediately. And so if you look at this image, I'm basically centering the patella, and I'm pushing down on the medial facet with my index fingers. And I'm not really lifting up with my thumb. I'm just feeling that that lateral facet is everting to neutral. And so if they evert to neutral, I don't consider a lateral lengthening. I don't consider a lateral release. But be careful with this. And on that same note, if you are going to do a lateral release or you're going to do a lateral lengthening, be very careful when you set the tension for your MPFL. And we don't even like to use the word tension, but this is a time where it's very easy to over-medialize the patella if you've done a lateral release or a lateral lengthening. So if you put your graft in for your MPFL and it's not isometric, two things are going to happen. Either it's going to be too tight, and you're going to have to go on to manipulation, and then you're going to stretch out the graft or pull out the graft. Or the graft is going to gradually stretch over time, and you're going to end up with the same problem you started out with or a more miserable patient. So here you can see an example where the tunnel was put far too high. We like to use the phrase high and tight. So if it's too high, as they start to flex, the graft either needs to lengthen or they're not going to be able to fully flex their knee. So I would encourage you in the operating room when you're doing MPFL surgery, first find your anatomic position by palpation. Secondly, check isometry. And third, check fluoro. So I think in this case, if you had checked any of the above, you wouldn't have ended up with this position. But certainly, if you had checked isometry and if you had checked fluoro, you would have not had this position. So again, the graft is in the wrong location. It may be too tight. It can either stretch out or it can constrain the knee. And that's a very miserable patient. Here you can see a number of issues. It may be hard to see, but the tunnels on the patella were too dorsal, and the tunnel was too anterior and too proximal. And so what this led to was a stress fracture. The patient went on to have a patella fracture. I didn't do this surgery. There's some very long K-wires there, but great images despite that. Here far too proximal and too anterior. And what you note on the patella is significant bone loss in the patella, and this is going to make your revision very difficult. And so if you see a patient like this, this is when you look up John Fulkerson's work and you consider doing an MQ-TFL because you can pass that graft around the medial aspect of the quad tendon. I would not put any more holes in that patella. It's lucky that it hasn't fractured. And put it in the right place on the femur, please. So even if you start out with small patellar anchors, they can cause a big defect if the cyclic loading from a non-isometric graft occurs. So here you can see on CT as well as on MRI, significant bone loss. This patient unfortunately was 20 when I met her. She was referred by the trauma surgeon. There was a thought that she was infected because she had large recurrent effusions and she ended up going on to have an osteotomy as well as a complete resurfacing patellar allograft, which is the last thing I want to do in a 20-year-old. Again here you can see a non-isometric graft causing significant patellar bone loss. This graft was placed too anterior. The patient still has significant maltracking. Now you have to do an osteotomy as well as an osteochondral allograft for that patella. Again, an unfortunate situation that I think I've repeated over and over again. If you put the tunnel in the right place, none of these things would have occurred. Arthritis now. Arthritis obviously is not something that you're going to pick up on a two-year or four-year outcome study. So here's a patient 10 years after an MPFL. So the patient was stable. You fixed one of the problems, but they didn't treat the maltracking. Now the patient had significant pain and chondral thinning due to their maltracking. This patient was revised with an osteotomy for her pain and arthritis. I would argue if originally you'd done an osteotomy with your MPFL, you may have avoided this or likely would have avoided this scenario. Here the tunnel was anterior. It was stiff. It overloaded the patellofemoral joint. The patient actually had medial patellar chondral loss. What's the next step? You can have salvage cartilage surgery. You can do an osteochondral allograft and redo the MPFL. Or depending on the patient's age, you'd have to salvage this with a patellofemoral replacement. Here you can see this graft was too tight. You can see sclerosis in the medial facet of the patella. This patient actually had fairly good cartilage remaining, so she was just treated with a lateralizing osteotomy. But again, the placement is really important. It can cause a lot of pathology. So my pros for MPFL, and then I'll move to a few short cases for osteotomy. But with the patella, use small anchors. I use all suture anchors. I think those are nice because they're cortically based. It's like using a G4, but it's made out of suture. Consider a quad turndown for revision or an MQTFL. Really make sure you center it in the trochlea. This is one of my first points in this talk, but when securing the MPFL at 30 to 40 degrees of flexion, make sure that you're not inadvertently, immediately subluxing the patella. I am very aggressive about osteotomies. If the TTTG is high, meaning above 15, or you see any degree of maltracking, katam to champ above 1.4, 100% of the time I'll do an osteotomy. And even lower depending on how much of a J sign they have. For the femur, palpate it, check the isometry, and then check fluoro. I used to use a mini CRM. It's impossible to get a good lateral. I've gone to a big CRM, and it's made my life immeasurably happier. And then as far as an osteotomy, Baja, real quick, you can look at this image. This patient was treated with a femoral nerve block, which she had a significant dysfunction of her quad. You can see her katam to champ is about 0.2. So I would strongly advise you don't use femoral nerve blocks, and move these patients immediately. I let them bend to 90 immediately. I don't use a CPM, but I don't think that's an unreasonable option. I treated this patient with a patellar tendon lengthening, but this is an impossible problem to treat. Here you can see a fracture. This is a scary, scary case, because this was 10 years post-op. This patient had a distalization and healed distally, but never healed proximally. You can see that proximal fragment. She just bent down to get something underneath her kitchen sink. That proximal fragment broke off, broke the screw. This is 10 years, so she clearly healed it distally. This was fixed with a plate and multiple screws. Obviously, that plate had to come out, but she actually did just fine. Be wary when you do a distalization. Make sure that you get good bony apposition. The whole length of your shingle, I actually use a bone block proximally. If anybody has questions, you can come up and ask me about that afterwards. Here this is actually my case. It's really hard to see. I literally would have missed it, I think, if I couldn't feel the tubercle moving when I flexed Disney at six weeks. This was a distalization. Basically, that x-ray on the left, if you look really closely, it looks like the bone block had shifted proximally, which indeed it had. What happened was it had split right through my screw holes. Basically, I went back in. I used just two, three, five screws, one with a washer. Then you can see that, I think it's a fiber tape there, fixing it distally with a swivel lock, bringing it back down. He did just fine, but this patient was flexing his knee to 140. I think 140 may be a bit much on a distalization. Immediately post-op, he had absolutely no pain, but he actually had no healing either. Here this was an over-medialized osteotomy. This is T2 mapping. You see the MPFL tunnels actually placed perfectly. Don't get the impression that I only see completely misplaced tunnels, but there's overload medially. Again, you typically aren't doing an osteotomy in a patient who doesn't have an elevated TTTG, but if you do, make sure you're not over-medializing them. Then under-correction. Here you can see the screw holes from the previous TTO. I do a lot of revision TTOs because a lot of times it seems that the osteotomy is in situ. If you're going to bother doing a tabletopical osteotomy, actually move it. This patient was quite happy. You can see they're well aligned. The patella is well centered now in the trochlear groove, at least on the AP, but it required two osteotomies to get there. Very quickly, as far as patellofemoral replacements, if they have instability and arthritis, most patients as they get older and they become more arthritic, their instability symptoms decrease, but if they're still dislocating, I would strongly recommend when you do a PFJ to add the MPFL. In these cases, I do use a quad turndown. It's unlikely to see a patellar dislocation with a total knee because you can externally rotate the femoral component more. You can rotate the component a little bit on a PFJ, but in these very ligamentously lax patients who've had years of instability, be careful. If they're still dislocating, consider an MPFL. Here you can see some maltracking. This patient may have been doing just fine. You certainly will see this sometimes in a patient where you can see it's a perfectly flat patella cut, but they're sitting laterally in flexion. I am pretty aggressive about doing an osteotomy in patients with a very high TTTG before I consider a PFJ, and I don't do it at the same time because I've actually had patients get years out of their osteotomy even when I tell them it's not going to work at all. If somebody has significant maltracking, maybe consider doing an osteotomy first. Although I show you this case where I think I got a very good result even though they were sitting perched, essentially subluxed, and I did a lateral lengthening approach, so lateral approach to the operation, and slightly externally rotated the trochlear component and medialized the patellar component. Last and real quick, there are some implants that are quite small. You can see on this lower left image a very small trochlear component with a lot of exposed bone around it. This was a miserable patient, and the patellar component was just fine, and so she was revised just to a full onlay trochlear component and did great with the revision PFJ. Thank you very much. Thank you.

revision patellofemoral surgery

failed MPFL surgeries

fractures

arthritis

osteotomies