Next, we'll invite Petri Salampa from Finland. He will tell us trochlea dysplasia management in patellofemoral surgery. Where have we been and where are we going? Thanks very much for having me. It's a great honor to talk about trochlea dysplasia, one of my favorite procedures. Nothing to disclose. Physical examination is a key role in patellofemoral patients and especially in suspicion of trochlea dysplasia. The more severe is the J sign, the more likely there's a high degree of trochlea dysplasia. And even if you have a habitual dislocation or so-called tight J sign or jumping J sign or whatever, it's quite likely that there's no other surgical solution than trochleoplasty to solve this situation. From the de Jure classification, type B and D are the ones who have excess bone under the proximal trochlea. They have the bump deformity and those are the ones that we consider trochleoplasty. A and C are typically managed without trochleoplasty. There's a lot of surgical techniques described in the literature. 1987, a breakthrough, Henri de Jure's deepening trochleoplasty in which the cartilage is cut in the middle, the excess bone is removed and the thick flaps are depressed in a V-shaped manner and there's a new trochlea groove created. An alternative in 1990s by Dr. Perider, so-called thin flap trochleoplasty, which means that the trochlea subcontral bone is removed to an excess that only a couple of millimeters is left and then the flap is flexible and the cartilage does not have to be cut so it stays intact. So some pros and cons. If there's some cartilage wear, thick flap technique is more safe. In a thin flap technique, the cartilage needs to be relatively intact to be able to flex it without breaking it. Two meta-analyses of 1,000 trochleoplasties revealed only 2.4% of redislocation rate. However, patella femora OA was reported in follow-up in 27% of cases, stiffness in 7% of cases and 17% of cases underwent some sort of subsequent surgery due to some kind of complication. So I think this evidence tells us that the deepening trochleoplasty, it's a good outcome procedure with very low risk of redislocation. However, I think we should be going to a less invasive, less scar tissue formation and especially diminish the risk of arterial fibrosis OA progression in long term. I think we can also improve in our diagnostics and patient selection. Lateral trochlear inclination angle has been proposed by some authors to be a diagnostic tool for significant trochlear dysplasia. LTI less than 10 degrees, it's comparable as B or D type trochlear dysplasia and it could be also simplified whenever it closes the zero, the trochlea is then flat or even convex and this is very useful tool that I use in my daily practice. A temptating arthroscopic trochleoplasty has been introduced by Lars Blond and of course very minimally invasive outpatient surgery. On the other hand, still some disadvantages, it's technically more demanding to fix the flap and additional procedures such as MPFR reconstruction or lateral lengthening which is more often used nearly 100% of cases still require incisions. So I'd like to present my preferred technique which is a lateral approach miniopentrochleoplasty. It's a thin flap technique, aspirator technique, a modification in which I leave the lateral trochlea intact and remove the excess bone from the proximal aspect and then keep the lateral condyle height as good as possible to get the inclination angle corrected. And once it's flexible enough, fix it with a one bioabsorbable screw and the lateral retinacular lengthening is required nearly 100% of the cases. So this is an eight month post-op, not bad scars I would say and we haven't seen any issues with the stiffness because of the quite aggressive rehab protocol following the isolated MPFL style. Here's an example how the trochlea shape can be really changed into a better contour and these patients are young and after we have removed the bump deformity of course the tracking has been corrected very nicely and sometimes these patients are also very physically active before they had problems and they can even return to playing quite a high level. We did some further analysis of the cartilage healing and one year results were presented a few years back, actually in AAS meeting and we could see that we didn't face any significant issues on the cartilage healing and by then we could already see of course that the B or D type dysplasia was corrected as an A or normal trochlea and extremely important the lateral trochlea inclination angle significantly improved as well as the other factors. A couple of post-operative second look arthroscopies, we can see how well the cartilage is preserved. We're starting to have five year results very soon. So I'd like to summarize. The physical examination has a key role, j-tracking, patella tracking should be evaluated in any case of patella femoral patient, deepening trochleoplasty, it's the tool to correct the dysplasia, cartilage viability seems not to be a problem and I think we should aim from stage salvage surgery to first line treatment in this kind of young patients with a high degree of trochlea dysplasia, although we still face difficulties with skeletal immature patients with open growth plates. Thank you very much. Thank you.

trochlea dysplasia

patellofemoral surgery

J sign

trochleoplasty

surgical techniques