0:00

Another area that's very interesting

0:03

that we should comment on the popal meniscal ligaments.

0:07

In all of us, there are two or three of these

0:10

and you can see them nicely,

0:12

particularly in sagittal images, which I'm showing you here.

0:16

Uh, these are three sagittal images starting most laterally

0:21

and then extending a little, not quite as far laterally

0:24

as we head toward the central aspect of the joint.

0:28

The first one we see is the antal inferior

0:31

popliteal meniscal ligament.

0:33

This is what it looks like connecting the posterior horn

0:36

of the lateral meniscus for the capsule

0:38

around the diving popple tendon.

0:42

As we go a little bit more centrally, we see the second one,

0:45

which is the postero superior.

0:47

There may be a space between these two.

0:50

We call that the popplet hiatus.

0:53

And then here is another image, slightly more medially,

0:57

and we can see a sub popliteal recess in this area.

1:01

A second space, far medially.

1:04

You may end up seeing the third popliteal meniscal ligament.

1:09

Okay, the pop, this is the postero inferior not present

1:13

everyone, so there may be three of these.

1:17

Now you can have developmental deficiency of these ligaments

1:20

or traumatic events that lead to tearing of them.

1:24

And this is something that you should look for, particularly

1:27

when dealing with pairs of the anterior cruciate ligament.

1:32

Here's an example for torn

1:35

inferior poppie meniscal ligament.

1:37

This was in a cadaver.

1:39

You can see the superior displacement

1:41

of the lateral meniscus here in a patient.

1:44

You can see this lax torn, uh,

1:48

a**l inferior poppie, uh, meniscal ligament.

1:52

And note the elevation of the posterior horn

1:55

of the lateral meniscus.

1:58

Sometimes this produces an interesting finding,

2:01

and this was a patient that was examined

2:03

with lateral knee pain.

2:05

I want you to look at the top two images.

2:07

Clearly all of the popliteal meniscal ligaments

2:11

or torn, there's a gap between the posterior horn

2:14

of the lateral meniscus

2:16

and the capsule then discovered what an mr

2:20

that was done one month earlier when the knee was locked

2:23

in this same patient.

2:25

And at that time, you can see there had been displacement

2:28

and inversion of the posterior horn

2:31

of the lateral meniscus lying adjacent to the anterior horn.

2:35

So this sort of abnormality can produce intermittent locking

2:40

of the knee involving the posterior horn

2:44

of the lateral meniscus.

2:46

Now, when we deal with tears

2:48

of the anterior cruciate ligament, one

2:50

of the things I've learned is you always have to study

2:53

in detail the posterior horn

2:55

of the lateral meniscus. There are a lot of things

2:58

That attach to it.

2:59

And here's my drawing, kind

3:01

of a sagittal drawing in the poster lateral corner,

3:04

showing you some of the things that may attach

3:07

to the posterior horn, including

3:10

the meniscal femoral ligament or iceberg.

3:13

I'm adding here, by the way,

3:15

that the Humphrey ligament may also be present,

3:17

and I want to call your attention to the fact this is

3:21

how you spell Humphrey.

3:23

He did not have an E in his name, so

3:26

that's the proper spelling of Humphrey.

3:29

Now, when the lateral meniscus translates forward

3:33

at the time of a tear of the anterior cruciate ligament,

3:37

as the tibial plateau moves forward, it is my belief

3:41

that the more common abnormalities you see,

3:44

peripheral failure.

3:46

This can take a variety of forms

3:48

and we have interesting names for what we may see.

3:52

This is a pop fatal meniscal ligament pull

3:55

with failure in the region of all

3:58

of the popliteal meniscal ligaments.

4:00

In a patient who has classic bone features of an ACL tear,

4:06

this is a berg rip.

4:08

You can see where the iceberg ligament attached

4:10

to the posterior horn, it has ripped away a piece

4:14

of the meniscus.

4:15

Again, in a patient with an ACL tear,

4:18

I'm not showing you a third one, we call the Humphrey hitch.

4:24

As opposed to that, when the lateral meniscus remains in

4:28

place, I think more often you see radial uh,

4:33

or essential problems,

4:34

and that may take the form of radial tears

4:37

or root ligament disruption.

4:39

Here's an example where the posterior horn

4:42

of the lateral meniscus remained in place.

4:45

Here's a large radial tear, okay?

4:48

Sharp deficit in the tip of the meniscus.

4:51

Classic features of an ACL tear.