0:01

As that as background.

0:02

Let's go now to our basic types of meniscal failure.

0:06

We're gonna start with circumferential

0:08

or longitudinal vertical tear.

0:11

Typically what occurs is axial compression placed on the

0:16

superior surface of the meniscus.

0:18

Now what does that do? That produces hoop stress.

0:23

So the initial pattern

0:25

of failure is a microscopic tear,

0:28

and I'm gonna put it in this drawing

0:30

and you'll see why it remains microscopic.

0:33

Here you see it extending

0:35

and it contacts one of those longitudinal

0:38

circumferential collagen bundles,

0:41

which prevents it from extending in this

0:43

particular direction.

0:45

So it takes the path of least resistance

0:48

and that path of least resistance is this vertical

0:53

longitudinal, because it has kind

0:55

of an antral posterior dimension.

0:58

And you see this in the peripheral aspect of the meniscus

1:01

where you have these longitudinal circumferential fibers.

1:06

These types of tears are present often in young people

1:09

following injury.

1:11

And in those involved in a variety of sports,

1:14

a longitudinal vertical tear.

1:17

Now, let's go back to my drawing.

1:19

I kind of like this drawing showing you those red tubes.

1:22

Those are the longitudinal circumferential collagen fibers,

1:26

and I'm throwing in a radial tie fiber.

1:29

And let's go ahead and place in this particular

1:32

transparent meniscus, a longitudinal vertical tear.

1:36

And we're gonna make it a long one.

1:38

So here it comes in yellow.

1:40

The longer this longitudinal vertical tear,

1:44

the more radial tie fibers that are violated.

1:48

And what do the radial tie fibers do?

1:51

They attach the central

1:53

to the peripheral portion of the meniscus.

1:55

So if you have a long longitudinal vertical tear,

2:01

you may get displacement of the inner margin of the meniscus

2:04

with respect to the periphery.

2:06

And what you end up with is a bucket handle tear,

2:10

a displaced longitudinal vertical tear.

2:13

So here's my picture.

2:15

Three dimensional of a longitudinal vertical tear in the

2:18

outer half of the meniscus.

2:20

Here I'm just showing you what it looks like, right?

2:24

You can see where it's located

2:26

between those collagen bundles.

2:28

The lent of this tear relates to its AP

2:31

or circumferential dimension, right?

2:35

We come along and image it in one plane,

2:37

and that's what it looks like.

2:39

And let's stay in the same plane

2:41

and we'll image it again right here.

2:44

And what does it look like? It's boring. It looks the same.

2:48

And by that I mean not only is it vertical,

2:51

but it's the same distance from the margin of the meniscus

2:56

that is characteristic as these tears tend to extend

3:01

between the collagen bundles.

3:03

And if it moves away

3:05

or toward the periphery, it's vertical obl.

3:08

And that, in my view, requires more force.

3:11

So this is the easiest path, the path of least resistance.

3:16

And that is why in fact, this line

3:19

of abnormalities is at the same distance

3:22

to the peripheral margin of the meniscus.

3:25

So here's an example of one first image.

3:28

Second image is boring. Here's another one.

3:31

Alright, here's another one.

3:32

These look pretty much the same on all of the images.

3:38

Now, a longitudinal vertical tear involving the posterior

3:42

horn, okay?

3:44

Of the lateral meniscus where we have a region

3:47

in which the Pope tears tendon extends

3:50

obliquely across the joint.

3:52

That is an area that in many of us has no red zone.

3:56

So that is why in some classification systems,

3:59

this particular type of tear in this location

4:03

gets particular emphasis.

4:07

If we look at a longitudinal vertical tear involving the

4:10

very periphery of the posterior corn of the medial meniscus,

4:16

we are talking about something that has been classified

4:20

as a ramp lesion.

4:22

Now I can tell you, if you read all the articles on ramp

4:26

lesions, you're gonna get a little bit mixed up

4:29

because there isn't in fact definite consistency on

4:33

what a ramp lesion is.

4:35

But let me give you some ideas about it.

4:38

We see it with tears of the anterior cruciate ligament.

4:41

Originally, I learned about it

4:43

as a double vertical peripheral tear involving the posterior

4:47

horn of the medial meniscus with chronic ACL tears.

4:52

Now in fact, that term ramp lesion is applied either

4:55

to chronic or recent pairs

4:58

of the anterior cruciate ligament.

5:00

And whether or not there are double

5:02

or single points of failure,

5:05

and typically that failure is at

5:08

or adjacent to the meniscal capsular junction

5:12

near the posterior horn of the medial meniscus.

5:16

There are certain characteristic findings, two

5:19

of which have been emphasized in the literature.

5:21

I'm showing you examples of what they look like.

5:24

Irregularity of the posterior margin of the posterior horn

5:28

of the medial meniscus.

5:30

And number two, fluid filling the region

5:34

between the posterior horn of the medial meniscus

5:37

and the joint capsule.

5:38

So this is what you are looking for.

5:42

Now, there is a third finding that I find very useful,

5:45

and that is marrow edema in the subj tibia.

5:50

Alright, whenever I find this particular finding,

5:54

particularly when dealing with a

5:56

Patient who has an anterior cruciate ligament tear,

6:00

I've learned, you've gotta look right above it.

6:03

You wanna look for meniscal pathology, you wanna look

6:06

for ramp lesions

6:08

because that can tell you, it kind of is a, a flashlight,

6:12

a bulb that kind of tells you there's something right

6:15

above it, and you're gonna be looking for partial

6:18

or complete pairing near or at the Meniscocapsular junction.

6:23

Now, another point about these longitudinal vertical tears,

6:28

excuse me, they're not always strictly vertical.

6:31

They can be vertical OBL as I show you in the diagram.

6:36

And if they are vertical obl, yeah,

6:38

they'll look vertical in the one plane,

6:41

but they can look horizontal in another plane.

6:44

So be aware of that.

6:46

You may in fact misread these as horizontal tears.