00:01
So to answer this question, i wanted to have this picture here so we can see exactly how bone repair occurs in each of the four steps.
00:11
So it's easy to memorize these steps, of course.
00:14
But i think once you understand, it becomes second nature and you don't have to think as much about what's going to happen next.
00:20
So that's why i want to go through each step so we can see exactly how to answer this question and to not memorize.
00:27
So the very first step of bone repair is going to be this hematoma formation.
00:34
So i like to think of the major themes that happen in each step.
00:39
So the first step is going to be hematoma formation as well as inflammation.
00:42
So i just want to explain a little bit about that.
00:45
So we see here in this picture, you know, once a fracture occurs, blood vessels are going to shear and rupture.
00:52
And this causes hemorrhaging.
00:54
So this hemorrhagic blood is going to clot over.
00:57
Time, hence the hematoma formation.
01:00
And then also simultaneously, you're going to have white blood cells come in here and basically clean up the debris of what's going on in this fracture.
01:09
So that's where the inflammation comes in as well.
01:12
You have this swollen, inflamed, tender bone occurred.
01:18
So that's the main theme here of the first step.
01:22
Now, second step, the main theme, i like to think of it simply as just, a soft callus.
01:28
Now we know it's going to be a fibro -cardiogenous callus that forms, but just think of it as a soft callus.
01:34
So the main things that are happening here is you're going to have fibroblasts come in that are laying down collagen fibers.
01:41
And you also have chondroblast coming in that are laying down this cartilaginous material...
