 We're going to start reviewing cases with a bang. Here's a sagittal projection. And I'm going to do a little drawing for you if you'll give me that luxury. I'm going to draw the humerus, which you see right here. Here's our beautiful humerus, rather simply defined. And then we've got the ulna that sits directly behind it. And that ulna has a coronoid process and an electronon. Now, I'm not very good at drawing the electronon, but there's our coronoid process. And so when we have a dislocation or a subluxation, the humerus is going to be pushed forward. And it's going to slam into the coronoid. And it may contuse it. It may fracture it. And there are innumerable structures that are here that may also be compromised. And we'll draw these in another color. So these may include some of the deeper fibers of the brachialis, the joint capsule, which I'll make in another color, perhaps purple. And either or both of these may tear. And if this displacement of the humerus is really violent, it may even start tearing tissues in the brachialis muscle itself. And once you see the brachialis muscle with a defect in it, you know you've got something really bad. Now, the other thing you want to do when you're looking at a major injury, and I realize I'm starting hard and then we'll work our way backwards, just to wake you up, is you look at the coronoid tip. And if it's a tip fracture, fine. That's a dislocation. But usually the more violent dislocations will get about 50% of the coronoid. And the really violent ones will get the coronoid at its base. And when you get the coronoid at its base, for instance, if you amputated it right here, you'd no longer have a groove for which the humerus to sit in. And you now have another major problem which is trying to stabilize the elbow after it's been reduced. Couple of other take-home points. Let's redraw again. And this time I'm going to tap into the radius. So you've already seen how the humerus will just lurch all the way forward, perhaps rupture the coronoid, and be sitting anteriorly. It may spontaneously reduce thereafter. You've seen that the coronoid may compromise. The insertions of the brachialis and the capsule may also compromise. But what about our poor little radius? So let's draw our humerus again, trying to do a little better job of drawing the humerus. And here is our radius, which normally would sit here. So now let's take our radius and erase it. And let's make our radius where it exists in a perch situation, a near dislocation. Now the radius is a little bit more posterior. This would be anterior. This would be posterior. So the radius is back, and the humerus is forward relative to the radial head. It sits right on top of it, and it may touch or also be sitting right on top of, or slightly fracture, the coronoid. Now when this happens, the radius is also rotated in kind of a supinated position. The other thing that happens is the humerus, which I haven't shown, is driven up this way. So not only is it posterior to the humerus, it's also driven more proximally, which I'm not directly showing you at this time, because I haven't drawn the ulna. Then let's see what happens in a dislocation. In a dislocation, I will draw your humerus one more time. And then after this, we'll look at the case. So I'll draw our humerus. My rudimentary drawing skills are on display. And now where is the radius? The radius is back here. Oh my. All the way posterior. This would be posterior. This would be anterior. There's a massive supination force, too. And then for our ulna, which I will draw in this time, here is our ulna with our electronon process. It's also in the back. So it's posterior, and it's also being driven straight posterior superior. So there's posterior forces. There's posterior superior forces. And then we've already discussed the forces on the front of the ulna. Now coupled with this, we're also going to have what I call wiggle-waggle forces. We're going to have forces in a dislocation that are going this way against the medial side of the elbow. So the forces will be going that way if there is a valgus force. Or forces may be going this way if there is a varus force. Or as they say in the Wizard of Oz, like the scarecrow did, it may go both ways. You may have a twist. So it may be both medial and lateral. Oh my goodness, you could end up rupturing everything. The front fractures the inside, the medial side, the outside, the lateral side. That's terrible. Does that happen? A lot. Now let's take a look at our case.