I do have a conflict that some of the hardware shown in this presentation I do receive some royalties for. If you're interested in a video demonstration of two techniques, a couple of my former fellows, Jonathan Shia and Dr. Vance have this video on the AOSSM website in their video library. So ACL reconstruction has been the topic today and obviously a lot of reasons for failure. I think a lot of good papers have been presented but I think the bony alignment and the bony anatomy is certainly a significant factor associated with ACL failure. And I've been doing reduction of the posterior slope of the osteotomy since 1996 where I went to Leon, my traveling fellowship and saw two cases that were performed by Philippe Noret of a deflection osteotomy with an ACL revision. And again, I think it's a developing area and we obviously have a lot more interest in the posterior slope and the association with recurrent ACL laxity in high-risk ACL patients. This was originally described in France by Michel Bonin. This was a PhD thesis that basically showed that if you had a posterior slope above 12 degrees, you had a significant increased risk of ACL tears. And so sagittal alignment has become more noticeable. This is one of my patients and you can see that obviously increased posterior slope and anterior subluxation of the tibia that's occurring. This is an older patient of mine and you can see the chronic anterior subluxation of the tibia even after ACL reconstruction because of posterior tibial slope. And again, many have looked at posterior tibial slope biomechanically demonstrating that increasing the tibial slope has abnormal increased stresses on the ACL. And again, it's hard to go through all the studies that have been performed but there's definitely a lot of biomechanical information that supports that anterior translation of the tibia is caused by increasing the posterior tibial slope. And again, the contact areas are changed and the anatomy of the knee is changed. Clinically, it's also been shown that ACL failure occurs much more frequently with increased slope. This was a long-term follow-up over 20 years of ACL reconstructions from Australia and basically showing that if the tibial slope was 12 degrees or more there was a significantly higher rate of failure in these patients. So when you combine young active patients with ACL tears and increased tibial slope, there's a definitely increased risk of failure. How about the tibial slope and the stresses on ACL grafts and ACL reconstruction? Again, a number of studies have been shown. This one by Imhof, again, showing that there's a significant risk. This study by Leprad and their group, again, showing that there's significantly increased risk and increased graft force with increased tibial slope. And early graft failure has been associated with increased tibial slope. And this is the results of that study. And so I think that you can increase the likelihood of ACL success by looking at the tibial slope. And both opening wedge and closing wedge techniques were described in this study. And this is a paper from David Dujour and the Leon group, again, showing the deflection osteotomy. And you should correct the slope if it's greater than 12 degrees, particularly in an ACL revision setting. And, again, I'll just show a few cases of mine. And, again, I think it's important to look at tibial slope when you're looking at these cases. The measurement of tibial slope has been talked about in one of the earlier papers today. And I think you can measure it relatively accurately in a short film, but you probably do it better in a long film. And you can do a staged osteotomy. You don't have to do an ACL revision at the same time. This is a case we did the osteotomy first and did the ACL revision second. Here's another case of a failed ACL reconstruction. You can see the increased posterior tibial slope. It's much more dramatic on a long-length view, as was presented today in one of the papers. And so here's the slope correction. And you can use fixation both on the medial and lateral side of the deflection osteotomy. You can do a tibial tubercle osteotomy, as was done here, and use the tibial tubercle as a bone plate as well, and put the tibial tubercle in the right location following the osteotomy. Again, you can stage the surgery in these revision cases. This is a case of multiple ACL revisions that continued to fail. You can see the wide tunnel. So we decided to stage this procedure. You can see the cartilage loss, meniscal damage. So the first stage, we did the joint preparation, and then the tunnel grafting, osteotomy, and then the second stage went ahead and did the ACL reconstruction. This is a very severe case, where you can see on the standing lateral x-ray, he's got anterior subluxation of the tibia. Also has a valgus deformity of the knee. So we did a stage procedure with a distal femoral osteotomy, and then the proximal tibial deflection osteotomy and ACL reconstruction at the same time. So in summary, I think you should consider a slope reduction osteotomy in these revision ACL cases with a slope greater than 12 degrees. You can use an opening wedge or closing wedge. I prefer a closing wedge osteotomy, because I think it is much more correctable with a closing wedge versus an opening wedge. But again, this continues to be a significant problem, and I think just food for thought for the audience. You know, how do you prevent an ACL tear with a high slope? And I think this is something that we need to continue to work on and look at ways that we can improve the outcome of these patients. Thank you.

posterior tibial slope

ACL reconstruction

ACL tears

biomechanical studies

slope reduction osteotomy