Chapters Transcript Role of Trochleoplasty Course: All Things Kneecap - Patellofemoral Issues, From Congenital to Degenerative All right, guys, thanks for hanging with us here. Nothing really to disclose with regard to this talk. So, as I go through my, you know, Danny was saying, once I'm more experienced, the more experienced I become, the more confused I become about the patellofemoral joint, and I think, um, you know, I, I feel like, uh, uh, Travolta here just like what, what's going on? The more I learn, the more confused this is. But let's see if we can make sense out of this one topic of troleoplasty. We're gonna go, uh, do a brief overview which Danny started us out with. A rationale for why we might consider a trochleoplasty. What are some of the indications, techniques, and maybe by the end of this talk you guys will feel a little bit better about it. So Danny already introduced troleoplasty to us real quick. What is trochleaa? We all know that we've been here all morning. Plasty means changing of shape. So basically troleoplasty is a procedure designed to address an abnormal shape or trochlear dysplasia. And there's two major types as Doctor Kaplan started us out with the non-deepening and the deepening. So the non-deepening types is the either bumpectomy or wedge resection, as well as lateral wall elevation, which is primarily of historical significance, and then the deepening ones are, uh, the two main types are thick and thin flap. Quick history. The original, um, uh, troleoplasty was that lateral wall elevation by Albee with bone graft interposition rarely used now. In 1964, Brastrom uh first described the association between patellofemoral instability and dysplasia, which we now know is a, a very important relationship. And the French first described a a changing of the trochlear shape to address instability in the late 70s. The most common, commonly known technique for troleoplasty is by the dujour and the Leon group, uh which was the modification of the mosa technique, and that is now known as the thick flap troleoplasty. And then some years later Bator and Gautier described the thin flap technique and then recently there's been some interest in arthroscopic. Real quick, we remember that the loss of soft tissue restraint is the key thing without which instability cannot occur, but we cannot ignore these as you guys been hearing all morning, these anatomic predispositions, the big 3 being the malalignment, the patella ulta and the trochlear dysplasia. So when we think about non-surgical treatment of of patellar instability, we know that the most significant predictors are being young and having trochlear dysplasia. So if you look at the combination of altered dysplasia at young age, you have an over 70% of risk of recurrence after first time instability. So then when we move on towards surgical treatment, right, and, and a lot of speakers here told you that MPFL. Dennis just uh described how MPFL reconstruction alone is a very powerful tool. So this is absolutely essential whatever your, uh, your tool is be MPFL and QTFL, a combination of the two, but when is it not enough and it's not enough when we have these bad players, right? tell all to malign and dysplasia and for the purpose of this talk, the trochlear dysplasia is one of the baddest players. So again described in 64 is an association with instability and you know in my practice um when I saw this number I was like no way I keep seeing, you know, every patient has dysplasia that's probably because of our practices focusing on instability because truly in the instability population as described by some studies upwards of 80% of patients will have dysplasia. As been mentioned, it is important for patella to engage in the trochlea to have that shape, to have that congruence when you don't have a congruent articulation. Well, Doctor Grecimer explained to us that articulation is never really congruent, but, uh, at least you have some congruence in the coronal plane early on in 20 to 40 degrees depending on whether you have volt or not. But if you don't, sometimes continuing all the way down into deep reflection, you still have dysplasia, you still have abnormal trochea, making it a lot easier for patella to dislocate. And you guys have seen the fact that there's a range of dysplasia from shallow to this cliff, and that's been uh classified by Dejour we can argue about whether or not the classification is valuable. It is the most commonly used one. some people are now moving away from using this classification classification just saying severe or not severe, but this is. The one you'll still see listed in radiology reports, etc. so basically shallow trochleaa with a sulcus angle over 140, 145 is a dejour A. A flat trochlear with a supra trochlear spur noted on X-rays is a B. C doesn't have a spur but has this hypoplasia medially and a convex, uh, lateral trochlear approximately, and then D has a cliff and is the worst kind. So I'm playing radiographs you guys I'm not gonna spend too much time with this. The key things I look for, I try to get a perfect lateral and I look for the crossover sign which is basically the trochlear rising above the uh uh proximal extent of the walls and the supra trochlear spur. If I see that, then I know that there's something wrong. Uh, you can also measure the, the depth. You can measure the height of the bump. Uh, the sunrise views can be difficult to interpret. We had a good, um, explanation of how if you don't position the patella correctly in a good lawn or merchant view, uh, you are not going to get the right image, uh, but we can oftentimes assess tilt and subluxation, but I don't really spend too much time measuring the sulcus angle. I think advanced imaging is key and we're gonna hear more about dynamic imaging, which I think is very important. But uh static imaging for now is still what we use, uh, whenever I can, I try to get a 3D image and analyze it to kind of see what how the 2D imaging matches what I see on the 3D and obviously there's no substitution to actually looking at it and there's uh now I've seen papers on creating 3D models to help us understand uh what this looks like cause it is a very complex anatomy. So, physical exam, you guys have seen some cool pictures. Now the two, I'm not gonna go through every exam for cell femoral stability. We heard about that, but The key things are the jumping J sign and the lateral glide past 30 degrees of flexion that you saw on Doctor Dennis talk how some people will continue having that instability and even all the way to 90 degrees. Uh, these are some of the patients, uh, this, uh, patient here was, I think Doctor Kaplan's recent case, uh, with a very obvious J sign, uh, jumping J sign even under anesthesia, and this is my. Patient, um, uh, who ended up having a, a troleoplasty with quite severe, um, instability, uh, you know, past 30 degrees of flexion and a positive, uh, jump in J sign and a study out of, uh, uh, Mayo, uh, recently published at AOSSM, uh, did notice that presence of the supra trochlear spur and high grade dysplasia particularly is associated with a jumping J sign. So traditionally, if you look at this uh JBGS reviews 2016, you see where the trochoplasty sits kind of at the bottom and listed as a salvage procedure, even though trochle dysplasia is listed right above it as as the main cause of the problem, but they still the answer is MPFL plus minus TTO and I would argue that, um, you know, nowadays there's definitely been a little bit more of a move of considering it as a first line treatment approach for some patients. I'm not advocating it for everyone, but I think for certain patients with severe dysplasia, it is uh an a possible approach. So why should you consider a trooplasty or rather what happens when you don't address significant trochlear dysplasia? These are some of my patients. This gentleman's 21 years old and he had a work injury, but he's, you know, he was uh. Uh, uh, from another country where they didn't really. Uh, follow him, and when you look at his knee, I mean, that's an arthritic knee at 21, severely arthritic with this almost bone on bone articulation in his lateral patellar, um, compartment. And this uh patient clearly had uh abnormal um uh abnormal trochlear shape which he's had his whole life. You can see his arthroscopic exam, the, the videos, the view from the superior lateral portal, uh, you can see he's formed a medial uh spur to compensate. You can see a long runoff proximately on the um on the trochla. You can see severe arthritic, uh, changes. And as this guy goes into uh um as he goes into flexion, About that. You can see how he's just grinding up along the lateral side. And so how did this happen at 21? I mean, he's definitely mal tracking, right? You can say he's mal tracking all we need to do is a TTO. OK, here's another one. Uh, this one is, uh, someone we operated on recently. She's 27. You can see she has clearly abnormal dysplastic trochlea. You see the, you see the spur approximately. And again, uh, from the superior lateral portal, you can see, uh, how she's just grinding down that lateral facet um of the patella and you can say, OK, it's all due to dysplasia. Trocha has nothing to do with it. Fine. Then I ask you about these two patients that I've seen. Significantly older, 34, clearly, it's not after a traumatic injury, it's just chronic instability. Look at their articulation. They have relatively normal grooves. Uh, and I can tell you I've seen a lot of these patients who are in their 30s and 40s. They have maltracking, they have some instability, um, uh, or typically mal tracking, and they have relatively normal or mild cartilage where they do not have severe arthritis. So I think a combination of bad trochlear dysplasia as well as um. Um, uh, mal tracking, uh, predisposes to arthritic changes, and I definitely think that's something that we need to keep in mind. So what, what's my way? What are my indications for considering troleoplasty as an initial approach to some of these patients? Obviously, salvage, it's still important when they've tried uh TTO and PFL and it's not working, then you gotta start thinking about that. But high grade dysplasia, B and above certainly and B andD particularly that have the supratrolear spur are on my hit list. Uh, if they have kind of that borderline, um, uh, TTTG and then we know that TTTG varies greatly with, with knee position, but if it's not that crazy 26, 28 millimeter, uh, mal tracking, uh, TTTG, then you start thinking maybe it's not really coming from the abnormal Q angle so much. If they don't have a significant alter that you need to distalize, uh, obviously, young age, you, it's hard to reshape cartilage once they, once you're getting older and unfortunately past 25 years older. Uh, for purposes of that and ideally no significant cartilage damage. So let's just go through the techniques real quick. This is the, that original LB osteotomy, which is lateral wall elevation. It's not commonly used anymore, but can be considered for the jour C where you get that hypoplastic and abnormally shaped lateral wall, also hypoplastic medial side, and you just want to raise the lateral wall to give it some restraint. Um, uh, again, the concern there is to create abnormal uh contact forces. The lumpectomy or a spur section is typically best used when their trochland may not be super severe, but does have a proximal bump that can lead to that ski jump and and help dislocate the patella before it even has a chance to uh engage. It can be done open or recently there's a nice article by Trasolini, uh, I think out of Mayo where they uh did this arthroscopic, um. Uh, arthroscopic evaluation, I think that's Aaron Critch's group, um, arthroscopic location of the spur. It's a little scary because it's covered by cartilage. So you have to find it on floral like that and then resect it, uh, with a shaver, or you can do it open, uh, with a little bit safer that way. Uh, this is a patient of mine that I did a bumpectomy some years ago. She was 32. She already had some arthritic changes. She had a prominent bump, uh, and you can see the difference before and after in addition to a TTO and uh MPFL reconstruction. She did well. Now, the classic uh tracheoplasty that we talk about a lot is the Leon or du jour technique of a thick flap or the barator thin flap which came about a little bit later. Uh, the modern instruments that we use help us, uh, uh, achieve these techniques. So what's the kind of indication from a deepening troleoplasty for me, it's a trochlea that's domed, um, you know, flat. Some people do flat, you know, if you talk to Lee Pace, anything that's not perfectly deep, it's gotta get a troleoplasty, but Uh, to me, if it's domed and there's a, uh, spur, uh, uh, past it, then I'm definitely considering, um, uh, deepening troleoplasty. The idea there is to remove the sulcus, uh, uh, by removing some canllus's bone and then impacting the cortical shell, and as Doctor Kaplan showed you, there's, uh, basically, um, the thick flap technique. Where you actually end up breaking the separation between the two shells and impacting them down and then I'll show you a video of a thin flap technique briefly where you uh elevate the entire trochlear as one so this is the thick flap technique uh here uh this is a patient of mine who was 17 has failed multiple surgeries. She started at 12 just an MPFL reconstruction. It was powerful enough to hold her for some years, but eventually. Uh, she started, uh, having instability again. She had a TTO and still had instability. You can see her severe dysplasia, her dejoy, she's basically perched on that cliff. And uh has a large spur. Uh, you can see the arthroscopic evaluation, her MPFL is holding just fine. You can see it there past the capsule. Um, and then what we did with her was a deepening trocheoplasty, and, and you can see how the spurs eliminated. The crossover is reduced, uh, so radiographically looks a lot better and clinically, she's done well. This is not her, this is another patient. That we did recently, again, you can see a severe trocheoplasty is a case that Doc Campbell and I did together. Um, some of the surgical pearls, you basically wanna mark out your new groove, uh, in, uh, in line with the uh center of your notch. I wanna get your elevation started, uh, using osteottones and the, and the some of the specialized devices. Very careful. We're trying to elevate 2 millimeter, uh, flap, uh, of cartilage and bone or really bone under the cartilage. We wanna eliminate the transitional bump. We wanna create a very smooth transition and you wanna use either your fingers or some kind of instrument to reshape the trochea. You have to be very patient, can't rush this uh surgery. And then you secure it with uh suture tapes. Uh, in Europe, they have viral tape. We don't have that here, so we just mix a lot of sutures together, and you can see a new groove created, and then I like to overse that uh intra-articular fat to kind of create a, a little bit smooth transition to help it heal with some fiber and glue. So, that's a, that's what a thin flap troleoplasty looks like and if you really have some, uh, you know, cojones on you, then you might try this arthroscopically, which I've been playing around with in my head. Uh, and that's a technique out of, um, uh, I, I believe, uh, Sweden by Lars Blonde, uh, and that's been described by some other authors, uh, and that can be done, uh, but, uh, I don't really have any experience with that. In terms of the outcomes between different techniques, the thick versus thin haven't really shown any difference in the, in the meta-analysis, and there are no really great head to head studies, obviously, because surgeons will do one or the other. In their preference, but overall there's been no difference in uh uh improving radiographic appearance, uh, as well as satisfaction rates and the overall redislocation rate is extremely low. The arthroscopic techniques again few um numbers reported, uh, and you can see even out of Blond's original study from 2014, uh, 1 of his first reports, he had quote. No complications, redislocations, or a fibrosis, but he did have subluxations when they did not address, uh, patients with a very high TTTG. You can see TTG of 28 or 40 millimeters. Obviously they need a TTO which they tried just uh troleoplasty that didn't work. And then patients, some patients had anterior knee pain for which they did a lateral release eventually. Another study recently uh reported a 1.5 year follow up with, with decent numbers as well. In terms of overall trocheoplasty outcomes and complications, this is the surgery that makes people nervous. I mean, you're digging up under the cartilage in this very important area that bears so much load with our daily activities. So we worry about complications and in reality they do occur, but, but not as much as people are. Scared of so this recent systematic review of uh uh 1 1000 knees with up to 25 year follow up, very low recurrent dislocation we know we're achieving great stability with the troleoplasty, um, uh, 2.4%, um, with residual sensation maybe of apprehension of maybe up to 8% in some cases, 7% a fibrosis, I think that's acceptable. However, look at the number of plofemoral arthritis, 27% in additional surgery 17. But the thing that you have to understand is um these studies that were analyzed here are are are very, very disparate in terms of both the numbers they report and the patient populations that they address you'll see some studies with just kind of teenagers and some studies and patients going all the way up into their 40s, so obviously you're gonna get some different degrees of arthritis and issues in these patient populations, and we definitely need better research on trochioplasty as such. Just so in summary, the outcomes of trochleoplasty that it's a pretty good procedure in terms of normalizing radiographic parameters, improving stability, functional outcomes, and return to activities, and there's no difference in thick and thin flap, but progression to arthritis is definitely a concern at long term and we have to kind of figure out the right patients to do it and uh, be aware of the complications. Don't be a cavalier if you're considering jumping into the world of troleoplasty. And just kind of putting it all together, um, the dysplasia, if you're treating patellofemoral instability or patellofemoral problems, they will see you more than you see it like that majestic snow leopard. Pay attention to the jumping J sign and the lateral glide past 30, uh, and on the X-rays, you know, start, start basic, start with your X-rays, get a good lateral supra trochlear spur in the crossover. I do consider it as a first line option now uh for select patients somebody who may not have that severe malalignment or alter who does have that high grade dysplasia with a spur and who's young and has normal cartilage. And when you're thinking of outcomes, will you tell your patients the outcomes are going to be good, definitely in the short term, they will are very uh likely to stay stable and uh but definitely be aware of long term progression to arthritis. Thank you and uh ask questions later. Published April 13, 2024 Created by Related Presenters Alexander Golant, MD View full profile
CME Knowledge Hub
