0:00

It's my privilege now to be able to introduce our,

0:04

our next speaker to you.

0:05

It's the first time he's participated, uh,

0:08

in the course this year, and that's Brady won,

0:11

and I'm really thrilled to do this.

0:13

Brady is the current, uh, chief of the division

0:16

of Musculoskeletal Imaging here at UCSD.

0:20

He's a clinical professor of radiology,

0:23

but that doesn't summarize ably how good he is.

0:26

I haven't told you this directly, Brady,

0:29

but you are a spectacular bone radiologist

0:32

and one of the best red

0:34

bone radiologists that I've ever met.

0:36

Uh, whenever I bring up something,

0:38

you always can cite the articles that, uh,

0:42

this particular observation may have appeared in.

0:44

So I, I really appreciate your clinical expertise

0:49

and I've assigned you a difficult topic to begin with,

0:53

and that is the lateral ligaments.

0:55

And after that, you'll have a case discussion.

0:58

So, Brady, it's all yours.

1:01

Thank you Dr. Resnick, uh, for inviting me

1:03

and for the kind introduction while I, I may,

1:06

if I may retort, while I may be well read, it's mostly

1:09

because I've read the articles, uh,

1:10

that you have written, uh, Dr.

1:12

Resnick, so right back at you.

1:15

So, um, to my chagrin, I'm looking at the title

1:18

of this article and, um, listening to Dr.

1:21

Resnick, uh, give us a nice, wonderful review

1:23

of the medial part of the knee.

1:25

I realized I should have also labeled this lateral

1:28

supporting structures, um,

1:29

but this was the title I was given, so I will roll with it.

1:34

So in terms of the lateral part of the knee, it can be more

1:39

or less simplified into two major components.

1:42

Um, a little bit more anteriorly,

1:44

we have the antral lateral complex, comprised

1:47

of the iliotibial band

1:49

and the antral lateral ligament, also known

1:51

as the mid third lateral capsular ligament.

1:54

And as we roll around to the posterior aspi,

1:56

the knee we'll encounter a complex structure referred to

2:00

as the postal corner, which I know can be scary to a lot

2:04

of radiologists, um,

2:05

and orthopedists when they try to evaluate this area on MRI.

2:09

But we're gonna go through this step by step

2:10

and hopefully break this down

2:12

so it becomes a little bit easier

2:14

and less challenging when you look at MRI.

2:17

So let's start first with the, an lateral complex or a LC.

2:22

There is actually a consensus group

2:23

that got together several years ago to really describe

2:27

what exactly is the anterolateral complex.

2:30

And even though the name is complex, there's not a lot

2:33

of structures to really think about.

2:35

Really, two major structures, the ileal tibial band

2:38

or tract, which could be subdivided into its deep

2:42

and superficial portions.

2:43

The deep portion is also known as the Kaplan fiber system,

2:47

and then followed by the antola ligament,

2:50

or again, the, uh, mid third lateral capsular ligament.

2:57

Now, Dr. Patria had reviewed, uh, pathology

2:59

of the iliotibial band by the hip,

3:02

and we know it is a complex structure by the hip as well.

3:05

It's associated with multiple muscles,

3:07

primarily the tensor fascia, lotto muscle,

3:10

and the gluteus maximus muscle.

3:12

And at the hip, we know it has a whole host of functions,

3:14

both flexion extension and abduction

3:17

and rotation by the knee.

3:20

We know that it inserts onto a bony

3:23

prominence at the ant lateral aspect

3:25

of the proximal tibia referred to

3:27

as gerdes tubercle at the knee.

3:31

It does have quite a few functions,

3:33

mostly resisting excessive internal tibial rotation relative

3:38

to the femur, but also does play a role in addition

3:41

to the ACL to resist anterior tibial translation.

3:47

The a LL on the other hand

3:48

and the ant lateral capsule only provide minor restraint

3:51

to internal rotation.

3:55

So we're pretty well, um, uh, we,

3:58

we can look at the Ilio TIB band fairly well on MRI

4:01

and primarily it's going to be coronal images as well

4:04

as our axial images.

4:06

And we can see this fa uh,

4:07

strong fibrous AP neurotic band again,

4:10

inserting on this bony prominence known as Gerdes Tubercle.

4:14

And this is something you can also palpate on clinical exam.