as a novel option for a glenoid reconstruction. Thank you to my co-authors for their contributions here. So funding for this work was provided by Stryker. Glenoid bone loss remains a challenging surgical problem with autograft and allograft options described. The distal tibia has been described and shown good clinical results. And it does a nice job of reconstructing the glenoid in the superior inferior radius of curvature, but it doesn't really anatomically reconstruct the glenoid anterior to posterior. Furthermore, considering the availability of grafts as well as costs, it's important to consider other options as well. No prior work has really looked at the dorsal aspect of distal radius for reconstruction of the glenoid. We did a study to evaluate the dorsal articular surface of the distal radius and see if it matched the radius of curvature of the glenoid and compared this to the distal tibia. We also evaluated the bone mineral density of the distal radius and compared it to other graft options currently available. This was a cadaveric study of 18 specimens. Work was performed by two shoulder and elbow surgeons. We did CT analysis looking at radius of curvature in both the AP and SI planes, and then also looked at bone mineral density for these grafts. On our cadaveric analysis, we utilized a digital caliper to measure the anterior to posterior and superior to inferior radius of curvature. And this was measured at three independent spots that were standardized and independently measured by two surgeons. We also looked at the graft length in the superior to inferior plane. We then created 30% defects of the glenoid and randomly assigned three radius and tibia grafts to the glenoid to visualize our reconstruction. This is our method of harvesting the grafts. So you can see here on the dorsal versus volar side of distal radius, we measured out our graft length, made our cut, and then you can see on the right-hand side, the reconstruction. Looking at specimen length, so the distal radius on average had six millimeters more length relative to the distal tibia. And we hypothesized this can be used for larger grafts or larger defects. Furthermore, if we look at the radius of curvature, all grafts had a nice SI curvature, but when looking at the distal tibia and the anterior to posterior plane, it's relatively flat. This was confirmed on CT analysis as well. Here's kind of a example of our reconstruction. So on the left-hand side, you can see the distal tibia versus the distal radius reconstruction. But I think more importantly, looking at the anterior to posterior plane, you can see how on the left-hand side, the blue arrow shows the distal tibia is relatively flat where you do have a anterior curvature to the radius that provides that potential buttress to anterior translation. We also considered the fact that the distal radius is not a weight-bearing surface or weight-bearing articular surface the same way the tibia is. So there's some concern that maybe it doesn't have as good a fixation or bone quality. But on our bone mineral density analysis, we actually found it to be fairly similar to the native glenoid and not significantly different than the coracoid or the distal tibia. Furthermore, with this graft, you're actually leaving the dorsal cortical bone intact. So that can augment your fixation as well. So in conclusion, the distal radius allograft has a greater mean graft length compared to the distal tibia, and we think this has potential for larger bone defects. Furthermore, it has a more acute radius of curvature anteriorly, which can provide an anterior buttress. And we hypothesize, we haven't done this yet, but that the dorsal radiocarpal ligaments could be preserved and potentially utilized for anterior capsular reconstruction as well. The bone mineral density wasn't significantly different than currently available grafts. And this is a novel option that we should consider and further biomechanical testing is ongoing. Some limitations to this is obviously just a cadaveric analysis. So still need to consider clinical outcomes and biomechanical testing as well. And then looking at radius of curvature, no bones of the glenoid radius or tibia is a perfect sphere. So we are kind of estimating the radius of curvature here for each of these grafts. And then obviously this was 18 specimens. So there's still some variance in terms of allograft size and availability based on the demographic of the donor. Thank you very much.

glenoid reconstruction

distal radius graft

distal tibia graft

radius of curvature

bone mineral density