0:01

<v ->So now, let's go to that third case.

0:05

It's a nice case for sure. (laughs)

0:09

I'm not here to show you bad case, just good case.

0:14

And this is, and this third case,

0:17

I wanna show you

0:20

an elbow.

0:22

An MRI of the elbow

0:24

of a 14 year old boy referring an elbow trauma

0:29

one week before, while playing volleyball.

0:33

Well, another player fell over his elbow,

0:37

and after that, he started feeling pain,

0:40

and limitation of the joint motion, and it was performed

0:44

an MRI and then CT of this case.

0:47

So this is case 3A, and 3B.

0:50

If you go to the site, is case 3A and 3B.

0:55

So, I want to use this case to illustrate the imaging

0:59

of articular fluid inside

1:02

the Hemarthrosis, and the displacement of the fat pads.

1:08

So, first I'd like to,

1:10

we can notice here that there is extensive edema,

1:14

bone edema of the proximal Radius.

1:17

We can see here, a small fracture.

1:20

It's hard to see,

1:21

but there is a small fracture of the head of,

1:25

the radial head in this area right here.

1:32

One important thing here, that I'd like to show,

1:35

is there Isn't like, a huge,

1:40

there isn't an intraarticular gap,

1:42

or an intraarticular bone incongruency.

1:47

So this would, the orthopedic surgeon.

1:50

If there is a gap,

1:51

I think it's two millimeters or something

1:54

more than that, the orthopedic surgeons,

1:57

he sometimes will prefer conduct,

2:02

do a surgery in the patient.

2:03

So, in this case,

2:04

there isn't any sign of bone incongruency.

2:10

So it's a radial head fracture

2:14

but there is no incongruency of the bone,

2:19

and we can see the hemarthrosis here,

2:24

why is this hemarthrosis, and not just normal fluid?

2:29

Because here in the T1 image,

2:31

we can see a high signal intensity in this fluid.

2:36

So, if it was just normal fusion,

2:38

it'll have a low signal intensity.

2:42

Dr. Resnick is gonna talk more

2:43

about that in the next lectures,

2:48

but one thing that I'd like to emphasize here is this.

2:53

So, here we have Hemarthrosis, and here it looks

2:57

like we have a area of fat

3:01

above the hemarthrosis here.

3:04

And we can, sometimes you can confuse this

3:07

with Lipohemarthrosis,

3:09

but in this case, that's not Lipohemarthrosis.

3:12

This is just the anterior fat pad

3:16

that is displaced anteriorly, okay?

3:19

And when you have x-ray of this case,

3:24

this is what they called it, the sail sign, right?

3:30

On the lateral x-ray of the elbow,

3:33

we can see this fat pad displaced anteriorly

3:37

when we have joint effusion.

3:39

And this is the sail sign

3:41

on the x-ray on the lateral x-ray of the elbow.

3:44

And sometimes that's the only finding that will

3:48

help us to identify a fracture

3:51

in the elbow when we are dealing with x-ray, okay?

3:57

So, now let me show you the CT of this case.

4:02

I will do a reconstruction here just to here. Yeah.

4:11

When doing reform,

4:14

look, here we have, this is the joint afusion,

4:20

the hemarthrosis,

4:21

and here we have the fat pad displaced anteriorly,

4:25

the anterior fat pad displaced anteriorly,

4:27

and the posterior fat pad displaced posteriorly, look.

4:31

And here, look, look,

4:34

that's the sail sign beautifully demonstrated here

4:39

on the CT.

4:41

By the way, on the x-ray the sail sign

4:44

is still more beautiful,

4:47

because the elbow is flexed, right?

4:50

And here the elbow is extended,

4:52

so it's not the best.

4:54

It's not the best angle for the sail sign.

4:59

I think that's it

5:00

for my last case of this block, Don.

5:04

<v ->Yeah. Thank you.

5:05

We're going discuss in a little bit

5:08

about those elbow fat pads as well.

5:11

Thank you so much.

5:12

Its great cases.