0:00

So here we have an axial T2-weighted image showing the

0:04

patella anteriorly. Easy for you to get oriented.

0:07

And let's look at layer number one,

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our most superficial layer which consists of the iliotibial

0:15

tract and its anterior expansion, which is right here.

0:21

And it's going to insert as we follow it down

0:23

onto Gerdy's tubercle in the tibia.

0:26

And there's the anterior expansion best seen along Gerdy's tubercle.

0:31

So now let's go up a little bit, back to where we were,

0:35

and the superficial portion of the biceps femoris.

0:38

So here's our big biceps muscle. Let's follow it.

0:41

Here's some superficial biceps femoris.

0:44

And then this posterior expansion right here. And the tissue,

0:47

this wispy tissue immediately anterior to it is part

0:51

of layer number one for the LCL.

0:55

Layer number two,

0:57

it consists of the quadriceps retinaculum anteriorly.

1:02

So let's go to the quadriceps up high. Here's the quadriceps.

1:06

And there is the quadriceps retinaculum,

1:09

coming off the quadriceps tendon.

1:11

And then two patellofemoral ligaments or retinaculum

1:15

more posteriorly, which we won't point out right now

1:17

since they're variably seen.

1:19

Like the medial side,

1:21

layers number one and two will merge or fuse together along with

1:26

the patella, just like they do on the medial side,

1:30

which has been articulated in a separate educational vignette.

1:34

Layer number three, the deepest layer.

1:38

It consists of the lateral joint capsules.

1:41

Let's move over to the coronal projection for a moment

1:44

and includes attachments to the lateral meniscus.

1:48

Here's one of them right here.

1:50

And the lateral capsular ligament,

1:52

which is seen as this linear structure right here.

1:55

There's the meniscofemoral ligament riding along the cortex

1:58

of the tibia. Now we see it separated from it.

2:02

And so these deep meniscocapsular components and the lateral capsule

2:11

the medial capsule provide layer three on the medial side.

2:17

Now, the LCL,

2:18

which is sometimes used as a synonym for

2:21

the fibular collateral ligament,

2:23

takes off right up here near the lateral femoral condyle/epicondyle

2:29

and sits above the origin of the popliteus hiatus.

2:32

We follow it down. It's usually linear or slightly arc-shaped.

2:37

It's located posteriorly.

2:40

As you can see, we're in the posterior aspect of the knee,

2:43

and it's located, although hard to appreciate between the superficial

2:48

and deep divisions. I might blow that up a little bit for you.

2:52

I'm going to blow it up. Deep division and superficial

2:56

division right here of the capsule.

3:00

It is considered a layer number two structure.

3:03

And that's somewhat confusing.

3:04

It comes on down and meets with its friend, the biceps femoris,

3:09

to form the misnamed,

3:11

now I'll zoom out, to form the misnamed conjoint tendon,

3:15

which sits on top of and inserts on the fibular head.

3:20

So, the LCL is a three-layered structure.

3:24

Some of its anatomy is very analogous to the medial side, some not.

3:28

Probably the least analogous is the fibular collateral

3:31

ligament or lateral collateral ligament.

3:33

And you could join us with other vignettes on this subject,

3:36

including the posterior lateral corner.