Good afternoon, thanks very much. It's great to be part of such a great panel, and greetings from Canada. I managed to escape. I'm not sure if they'll let me back in, though. Another disclosure I have, beside the standard disclosures, I do mostly soft tissue grafts, so I don't encounter this often, but I do use PTB for revisions, so I have encountered it in the past. So as you know, trans-tibial grafts, you had more tunnel length to deal with, so grafts weren't very often too long, and usually you had 25mm bone blocks. But now that we've switched to largely AM drilling, we run into this more often. The portals are down low, the tunnels are shorter, and sometimes I think we're down too low, and some of the biomechanical studies show that we're getting too low, but that's another subject. But anyways, we did a randomized clinical trial using hamstrings of AM versus trans-tibial. Not much difference, as you would probably be surprised at, but the mean angle on the x-ray was markedly different, 43 for the intermediate, 58 for the trans-tibial, so it does make a big difference. So you get into this situation where if you use your standard technique with a BTB graft, sometimes your graft is going to be sticking out the tibia, so that becomes a bit of a problem in terms of fixation on the tibial side. So this is your anatomy, and there's been some articles published on this, mainly with regard to allograft. The Rush Group has talked about graft mismatch, mainly when you're doing an allograft BTB, which we don't do much of anymore. And then Mendelbaum talked about it with his group in terms of mismatch, but they did study the length versus the height of the individual, the length of the graft and the total graft length. The total graft length is usually around 95 to 105, you have 25 millimeter bone blocks, and the tendon itself is 45 to 55, and as you might expect, the interarticular length varies with patient height. The average is about 45 for your tendon length, so that you can keep that in your head for an average height individual. And if you look at the different height measurements, there's the bottom, the average of being about 45. So male versus female, not much difference actually, 43 for the females and 46 for the males. And what about patella alta? Well, this is a challenging situation and you're going to have some long grafts, you're going to have some mismatch and the graft being too long. So in that situation, there may be different things that you can do, which I'll outline. So possible solutions, burying the graft on the anterior tibia, making a little trough, trimming the graft, and this is what I usually do now that I'm doing AM portals, I usually trim the bone blocks down to 20 millimeters, and you can add extra fixation as well. You can lengthen the femoral tunnel, make it a deeper socket by reaming all the way out to the lateral cortex, you can trim the bone blocks as I mentioned, and then change your femoral drill angle to make it just a little more vertical and get away from this. You can also make your tibial side a little more vertical. Extreme patella alta, though, you may end up with soft tissue on your tibia side and have to fix the soft tissue on the tibial side. So recommendations to stay out of trouble, make it part of your preoperative planning just like anything else, looking at the MRI and the plane x-ray and trying to visualize whether or not you're going to get into trouble. Draw out and template your tunnels, beware of patella alta, and be able to shift gears intraoperatively in terms of graft fixation, have backup fixation handy, and then you should be okay. Thanks very much.

graft length

trans-tibial ACL reconstructions

AM drilling

preoperative planning

backup fixation