0:00

<v ->And then perhaps most interesting,

0:03

although the classic description

0:05

of a bone contusion or bruise,

0:08

talks about hemorrhage and edema,

0:12

there is another finding that you may see

0:15

and not just with bone contusions,

0:17

but with bone fractures as well.

0:19

And that area is a fat, okay?

0:23

Often surrounded by an inflammatory reaction.

0:28

These are areas of fat necrosis.

0:32

And if you look for them, you're gonna find them

0:34

in many of your bone contusions and fractures

0:38

shown here in this example.

0:40

Here's a nice case shown with a bone contusion

0:44

of the proximal tibia, these fat globules.

0:48

So let me end with a concept

0:50

that maybe with extensive bone injury,

0:55

there's hemorrhage and edema

0:56

in the fatty marrow necrosis and death of fat cells,

1:01

they are released,

1:03

they migrate away from the area of injury,

1:07

they undergo inflammatory reaction, okay?

1:12

And you can find this surrounding inflammatory reaction

1:16

with macrophages and giant cells.

1:19

They continue to migrate away,

1:22

and you can imagine that with massive injuries,

1:26

they may enter vascular structures

1:30

and lead to distant fat embolization,

1:34

a well known complication of major skeletal trauma.

1:39

So what I've done in my final lecture,

1:43

is to cover the subject of chondral, osteochondral

1:47

and subchondral injuries, I've tried to emphasize, anatomy,

1:52

pathophysiology, terminology, and MR imaging.

1:57

Let's turn the program over now again to Abdalla,

2:01

who is going to show us some final cases.