0:01

Here is a knee of a teenager with joint pain.

0:05

So, as we sort of went through it

0:08

the first run, I couldn't really find

0:11

anything wrong with this patient.

0:13

And then, I noticed that there was a plica.

0:16

And there's a plica right over here.

0:18

This is at the medial aspect of the joint.

0:21

This is the sagittal fluid

0:23

sensitive fat-suppressed sequence.

0:25

Here's that sagittal fat

0:26

sequence that I love so much.

0:27

You can see the little string right here.

0:31

And that corresponds to, on the axial

0:33

images, if you will, this corresponds

0:36

to this structure right over here.

0:39

And boy, it looks awfully innocuous, doesn't it?

0:41

It looks like a tiny thing, it's not

0:43

bothering anybody, it's just hanging out.

0:46

But it's located at an unfortunate area.

0:50

If you notice, it's draped

0:51

right over that femoral condyle.

0:54

Right over here, draped right over

0:55

the femoral condyle, where the little

0:56

cartilage is present, cartilage is present.

0:59

So, people say, well, is it really

1:01

worthwhile to mention these little

1:03

plicae, uh, when we see them on MRI?

1:06

And this is a good argument for why it

1:08

is important, and I'll show you why.

1:10

You're actually not going to find

1:11

any cartilage problems on MRI.

1:13

It's beyond the resolution

1:15

of any MRI we have right now.

1:17

But I'm going to show you an arthroscope

1:20

of what this area looks like, and what

1:22

the sequelae of this very thin plica are.

1:27

So, this is the arthroscopic view,

1:29

and I'm going to show you this video

1:31

as, and I'm going to orient you here.

1:34

We're looking right here, this thing

1:36

is the plica, and you'll get a better

1:38

idea of how big it is, how long it is.

1:40

This here is the condylar surface,

1:44

the anterior condylar surface,

1:45

and this up here is the patella.

1:47

So, they put fluid in the joint and

1:49

extended it such that the patella is sort

1:51

of elevated away from your femoral condyle.

1:54

So, let's see what this video looks like.

1:58

And so here's the plica here.

2:00

And actually, you notice it's very sort

2:01

of wavy and it's emanating from the

2:05

superficial aspect of the joint coming down.

2:08

So, this is what that plica looks like.

2:10

Okay.

2:10

So, let me show you some still images.

2:12

So, here the plica has been elevated

2:15

away and you see this little

2:17

contour irregularity at the femoral.

2:20

This is the patella.

2:20

You can tell this is the patella.

2:22

And this is the femoral condyle

2:24

and there's a little abrasion here.

2:26

So, that little tiny plica, as it rubs

2:29

against the femoral condyle, causes

2:31

this irritation or problem and causes

2:33

quite a bit of discomfort and pain.

2:35

So, anytime you see a plica, I think you should

2:38

mention it in the report, particularly if you

2:41

see the plica intimately associated with some

2:44

kind of a chondral or cartilaginous surface.

2:47

So, what did they do?

2:48

They went in there and they, um, cut the plica.

2:51

So, here it is cutting the plica away.

2:54

And here it is after they've

2:55

debrided that plica area.

2:57

Okay, they've completely taken it

2:59

away and the patient was completely

3:01

asymptomatic after the procedure.