Thank you so much. This talk is going to be about anterior glenoid reconstruction with bone block technique. Again, my name is Steve Barada. I'm from the Medical College of Georgia in Augusta, Georgia. I do have disclosures that are relevant to this talk. As you can see, I'm a consultant for both Arthrex and Xactech. This is our case presentation. This is a 30-year-old male. He had had a history of recurrent instability. He was treated at an outside hospital. You can see his distal clavicle. First, they had attempted harvest from that, but they felt the bone quality was not sufficient, and so they harvested the coracoid. However, the short length of the coracoid harvest only allowed for a single screw for fixation. This is their immediate post-op film. This is when the patient came to see me, four months post-op. He has continued recurrent instability, and obviously now at this point, this has failed to unite. So what now? Well, what now is we need to do some type of a revision bone block procedure, and that takes us into this talk, and we're gonna talk about DTA, distal tibial allograft. Ideal indications for this is obviously failed latergy, and in my practice, I see a lot of failed latergies, and so I think in the setting of a failed latergy, that is really the absolute indication for allograft distal tibia. However, there are some cases that we think even significant glenoid bone loss, however, for primary surgery, not in a revision setting, it's also a good indication for this. Relative instability in the presence of arthritis, for me, I really don't wanna distort a lot of the neurovascular anatomy, and so I'll do a DTA in that setting. Those historically, those patients, however, do not do fantastic once they already have arthritis, of course, but with the upcoming need for arthroplasty, less alteration of the neurovascular anatomy, and then there's this consideration for patients with non-ideal coracoid anatomy. What is non-ideal coracoid anatomy? Well, you can see the lateral bend, significant lateral curvature of the one on the right there, also large CA tubercles, or these knife-edge lateral borders that are gonna become the new articular surface. Maybe these are not great coracoids to be doing this case on, but the biggest disadvantage, if you're doing a DTA in a primary setting, is the intact conjoint tendon, so you really have to be careful for the medial retraction. You can see this case here, the CT cut lets you know this is gonna be a struggle. He has a very lateralized coracoid that's gonna really get the conjoint tendon even more lateral to the glenoid and really facilitate difficult exposure, so you can kind of have a sense going into this knowing from the CT scan, but back to our case, this is what we wanna reliably do. Take the X-ray on the left to the picture on the right, and again, really everything that we know about DTA can be attributed back to my good friend, Matt Preventer, who really came up with this and was the champion for this technique, so selecting a graft, we've looked at a lot of distal tibia MRIs, trying to make sense of the articular surface there and get a sense of kind of the lateral variation of the anatomy, but we found out that 85% of these will have a straight or nearly straight lateral border to allow the retention of the cortex. You can use that cortex to put your screws against in these type Cs with a really deep curvature. That's pretty rare, so we use non-laterality, non-sized, non-gender matched, fresh, which means never frozen allograft distal tibia. That means we have intact live chondrocytes, and you can see, you can get your rectangular graft here. It just has variations of how you're going to be able to get that based on the anatomy on the lateral aspect. So this is our biomechanical study here loading our distal tibia allograft that we had put up against a bone model substitute to see if retaining the lateral cortex, how much that mattered, and what we found was that the use of washers matters more than the retention of the lateral cortex. So now that we know that, we can make this graft completely cancellous if we have to based on that variability that I showed on the last slide, and then we just use washers, and we know that's even stronger than if we were able to keep that cortex. So there is a DTA graft preparation station available. You can also fashion the graft without it just by careful technique, but certainly this graft preparation station that Dr. Preventer developed does make this a lot more easy to prepare that graft. I like to start this before the patient comes into the OR. In most of my cases where I can preoperative template, so I know what the size of the graft is going to be. I have a separate back table set up, and I'm usually finishing up the graft by the time the patient rolls in the room. So I'm able to harvest this graft here from the lateral aspect of the distal tibia where that curvature normally fits very well. So if we're able to retain the cortical side, we want to keep that for our screw fixation. That cancellicide is going to go up against the glenoid neck. This is a big graft with a lot of surface area. So we do feel that pulse lavage, removing those marrow elements can really decrease any type of allergenic response, hopefully limit graft resorption. You can see the graft really does look pretty washed out after we use the pulse lavage. And then I like to use some type of biology to make this graft more likely to incorporate. So I'll use PRP. The patient wants to pay for that or for insurance will allow it. Otherwise, I'm just going to aspirate iliac crest and we'll use non-concentrated iliac crest just with a bone marrow biopsy. We're going to do that before we sit these patients up in the beach chair. This is a lot easier when they're supine, even in these patients who are thin like this person. And then we have that graft soaking in that. So again, here's our distal tibia. I do this through a standard beach chair approach. It's a pretty relaxed beach chair approach. So I can look down on the glenoid. This is a vertical instability incision. We're going to still go through the subscap split. In this revision setting, I use a split just above. So just superior to the previous split. That way if there's any conjoined tendon still scarred in, I'll leave that intact. I'm going to carefully separate this out and I want to be able to get this exposure. So how do we get this? We want to be able to create this nice flat bleeding bed of bone on the glenoid neck. So you can see with the marker, I've marked previous holes on the face of the glenoid so I can avoid those old holes with my new screws. For cases of considerable bone loss, I'm going to go ahead and use a larger graft. That graft, my typical graft is about 22 millimeters in height. These larger grafts of three millimeters, I'm sorry, three centimeters, I'm going to provisionally fix with K wires and then place my screws through them. So you can see here, I'm using a sizing guide to just confirm I have a nice flat bed. And then in these revisions, I like to pin this using small pins way out at the periphery. And then I will use a cannulated drill. I think the cannulated drill is nice, but I'm using solid screws. So again, a cannulated drill just to kind of really make sure I can pin that in place first and then over drill that. And then I'm putting solid screws in and I'm going to use washers again because of that biomechanical study with or without sutures around it for capsule repair. If they have capsule that I can bring back, I'd love to do that. And here you can see the fit of this distal tibia just fits the cartilage surface very nicely. The goal of the glenoid reconstruction is to replicate the contour in both the axial and the coronal plane. And so what that means is the orientation of the graft and our subsequent screw placement, especially in this axial plane, is going to depend on the amount of bone loss. So I don't really get hung up on making my screws completely parallel to the articular surface. I just really want my screws to be in a good position to get good graft compression. So sometimes in large bone loss, that means your screws are going to look like this to get the most, the maximum amount of compression of your graft. And then here we can see the, bring the humerus back in place, rotating the humerus. And the graft is of course, just a perfect fit for the contour of this glenoid. These cases are very rewarding and patients do very well after this, but you can see that fit is very nice. In the beginning, I would encourage you to get CT scans at the four month mark, getting CT scans before four months. It's hard to determine graft incorporation, but it's nice to give yourself feedback on these. I don't always do this now, but certainly in the beginning, I found this very helpful and you can really look at your graft placement, your screw placement, and really get a good sense and help yourself for subsequent cases. And so again, ideal indications, these failed latergies, large amount of bone losses. We do have some relative indications. And again, preoperative planning for the size of the graft, I think is important. Preparation prior to the patient entering the OR can really help offset the cost of this graft if you're working in a hospital or a surgical center. We don't need these to be matched. Again, I use these non-size match, non-laterality matched, and this graft can be cortical or cancellous. If I have to make it cancellous, I'll just use screws. And the advantage of utilizing articular cartilage, that's the big advantage of these grafts, as opposed to iliac crest. And we're still doing this through a subscap split, so the rehab with this honestly goes very well. We don't need to take the subscap down. These patients, we expect them to be able to get back full range of motion. You can see the orientation of that vertical nature of that incision there for the instability incision. Still delta pectoral interval, but it's through that vertical incision. And again, these patients can do very, very well. So thank you very much. Looking forward to meeting all of you at the course, and feel free if you have any questions to find me, and we can always talk about DTA. This is one of my favorite procedures to do. Take care, everyone. Travel safe. And so thank you very much. Please don't hesitate to reach out to me or any of the instructors that you meet during this course if you ever have any questions. And thank you again for attending.

anterior glenoid reconstruction

bone block technique

distal tibial allografts

glenoid bone loss

fresh allografts