Next, we'll have Dr. Vidal presenting on Correcting Alignment, Are 3D Scans and Patient-Specific Osteotomies the Future? Thanks, Armando. Thanks, Brian. Excited to be here, and thank you very much for entertaining this topic. It's near and dear to my heart. So my charge is to talk about where is osteotomy going in terms of 3D planning and PSI. I don't have any disclosures as they pertain to this talk, but I think it's important if we're going to talk about where osteotomy is going is to understand the historical context of where we came from and how this started. So osteotomy is probably one of the oldest orthopedic operations. It dates back 2,000 years, really used for deformity initially, but it gained popularity really in the middle of the 20th century where there were limited options for knee osteoarthritis. Really it was osteotomy and arthrodesis, but it established the concept that offloading a joint or alignment can delay joint degeneration. Now the problem is that by the 70s, you start seeing a variety of different techniques, and coupled with that are mixed results, some of which are really not great, and you have the advent of modern arthroplasty, which really has excellent outcomes, and then osteotomy essentially gets relegated to the dustbin of orthopedic history. Now fast forward in the 80s, you start seeing really the invention of modern joint preservation. You have Dr. Steadman and Vail reporting on microfracture, first reports of ACI and osteochondroallograft. By the mid-80s, you start seeing reports on meniscus transplantation, and you see an explosion in terms of research on all the topics that we've been talking about this morning. Now coupled with that, you start seeing predicting what are the predictors of success or failure, the things we like to talk about, alignment, meniscus status, stability, and then you start seeing in a trailing fashion an explosion in research on osteotomy, how to implement it, outcomes, et cetera. Now the challenge is that HTO and DFO are really still stuck in the 70s, and this will look familiar to all of you that do osteotomies, is oftentimes we'd use plain radiography with the old acrylic films, but now we use digital radiography. But we're making these measurements. We may be off by a couple millimeters, and it really is imprecise, in my opinion. And then you couple that with the surgical implementation, and this will be familiar to people as well, where you use these awls. You kind of measure it with a metal ruler, and you say, yeah, that's pretty close, five or six millimeters. And then you use an alignment rod or a bovie cord, which is really subject to quite a bit of rotation, parallax, and I would argue surgeon confirmation bias. We'll put that rod wherever we want, just to say, I think my alignment's in a pretty good spot. Now the challenge, I think, is if you look at the outcomes in the literature about what is acceptable from a surgical accuracy standpoint, I think you'd be surprised to find that accepted tolerance is plus or minus 3 degrees. Now my average osteotomy is probably between 5 and 10 degrees, and I would argue that's an unacceptable range for a lot of the very sophisticated cartilage procedures that we're doing. And if you look at it critically, only 85% of patients actually fall within that range, and 15% can be widely off. Now people have looked at navigation to try to improve that. Navigation is no better, and frankly, may be marginally worse. And we're just talking about coronal plane. If you look at sagittal plane, and we talk about revision ACLs, et cetera, that'll be in the next section, our tendency is to increase slope. So we really have quite a bit of imprecision in accuracy in how we do this. So this is where I think we're going. I think that the technology needs to match what we're doing with articular cartilage repair. We'll use the, I've been doing this for about two and a half years, we'll use CT scans, we'll superimpose it on the long alignment film, and this helps you with your surgical planning in terms of understanding where the deformity is, what the slope is doing, the differential slope between the medial and lateral sides, and then you can plan your correction with quite a bit of precision. Now in addition to planning the correction, you can also execute in a more sophisticated fashion. So there are a couple of companies that do this, I have no financial interest in any of them, but the guides themselves are actually 3D printed, and this is a company that uses a novel technique where you use drill bits to actually create the osteotomy plane, and it's beyond the scope of this talk, but it allows you to create a hinge access that is variable, and actually unachievable in my opinion with a freehand technique. The milling of the plate, which is also patient specific, allows you to accommodate these fairly complicated procedures, revision ACLs, you see the screws are avoiding the ACL tunnel here, meniscus root tunnels, et cetera, and you can actually even build some of those guides into the osteotomy guide itself. I think it's best just to show you the technique, I think it probably captures it well, this is a very brief video, but you get a 3D print of the patient's tibia itself, again the guide is 3D printed to the tibia, and actually keys in, I'd say 95% of the time, very, very easily. You can still check and confirm that your osteotomy plane correlates with what the template is, so I'll often provisionally put it on, I'll put a pin across just to confirm that my osteotomy plane is where I want it to be, and usually, this is my fellow doing this, it's about a 40 to 45 minute procedure, so in addition to improving precision and accuracy, I think it creates a level of safety that is enticing, because I think a lot of people avoid osteotomy because they're worried about the complications and the morbidity. So the osteotomy is actually created with these drill bits, and then it's completed with an osteotome, so essentially it's like a perforated sheet of paper, and you just complete it to a predetermined depth. The guide then gets disassembled, it's a really novel, I think several people on this panel have been using this, or a variation, there are just two companies that I'm aware of that use computer-aided design for osteotomy creation. This thing becomes disassembled, and then the back of the guide actually acts as your jack to open up the osteotomy, which is again where you can create quite a bit of imprecision. And then, if anybody's read Dr. Noyes' article, probably 20 years now, from probably right around 2000 or so, he talks about the law of triangles, and we all know that if your gap angle, meaning that the angle between the posterior aspect of the gap and the anterior gap is not appropriate, you will increase slope, so then you can also ensure that your posterior gap and anterior gap are exactly to your template. I think that's the challenge, right? When you template one, you say it's five millimeters, where in the osteotomy is that five millimeters? But this allows you to be very precise with where the correction should be, and then you drill it, and then essentially the plate goes on, and the soft tissue envelope gets repaired over it, and the plate itself is patient-specific. In the interest of time, I'll just move forward. I think there's a lot of data that's emerging on this. We know the coronal plane is accurate, and the slope is preserved with these cases. We get accuracies that are within .1 to .2 degrees. We just completed a cadaveric study that we're reviewing the data. We're going to look at our clinical patients. We have well over 100 in our practice at this point, just to confirm in a clinical scenario that this holds true still. So in summary, I've used this for simple HTOs, DFOs, slope corrections, complex dual-level osteotomies, and even complex revisions of failed osteotomies or malunions from tibial plateau fractures, so very versatile technology. So my opinion, HTO and DFO have an increasingly important role in joint preservation, ligament reconstruction, still in DJD in the young and active patient. Accuracy and precision are the keys to success, and I think we need to leverage technology for that precision safety and to allow for concomitant procedures. Thank you. Thanks.

osteotomy evolution

orthopedic surgeries

3D planning

patient-specific osteotomies

3D printing technology