0:00

Knee anatomy,

0:02

cruciates the PCL on MRI.

0:05

Let's return to the coronal projection for a moment to see where we are.

0:09

We're down low at the insertion.

0:12

There is the insertional footprint of the PCL.

0:14

It's fairly broad.

0:16

There is a medial bundle, a posteromedial

0:19

and an anterolateral bundle.

0:21

This patient does not have a very prominent meniscofemoral ligament

0:26

of wrisberg, which is not uncommon seen in about 20% of individuals.

0:31

Before we scroll the axial, which is probably my least favorite projection

0:35

for the PCL, let's scroll the coronal for a moment.

0:38

I want to show you one other thing.

0:40

Look at the inferior fibers of the PCL.

0:43

We've got our medial bundle and our lateral bundle.

0:46

But these inferior fibers may sometimes separate out and produce

0:51

some confusion for when they're really separate. This structure right here may be

0:56

confused with a loose body or a bucket handle tear.

1:00

Now let's scroll back and forth.

1:02

The way to avoid this pitfall is to follow the fibers back up to the PCL.

1:07

Separate.

1:09

Together.

1:10

Separate.

1:11

Together.

1:12

Now, let's turn our attention back to the axial.

1:15

We're going to ride our PCL from posteroinferior to anterosuperior.

1:21

We're below it, all bone.

1:24

Now the insertion.

1:27

And now let's ride it forward.

1:29

Let's keep going.

1:31

Here's the PCL, which is a more rounded, thicker structure in cross-section.

1:37

The ACL, more linear.

1:39

It's along the inner wall of the medial femoral condyle.

1:42

And there is the very broad footprint of the PCL, which is complex and broken

1:47

down into 16 zones or regions, which is far beyond what we want to discuss today.

1:52

But do remember that the PCL is fatter, more round, more bulky than the ACL.

1:58

And because of its configuration, in which the medial fibers and the lateral

2:03

fibers may turn or twist or cross between each other, the PCL, when it tears is going

2:09

to tear more often interstitially like this, and it'll blow up like a balloon.

2:16

Whereas the ACL, which is more like

2:19

a celery stalk configuration, more parallel, will often tear with a cut like this.

2:28

Now, if the PCL is cut and separated, you have to be worried about a more serious

2:33

catastrophic injury, including a knee dislocation or a complex pattern of knee

2:38

injury, or potentially a fracture in the posterior aspect of the tibia.

2:44

So different appearances of the tears, the PCL and ACL based on anatomy.

2:50

Let's move on, shall we?

PCL: Axial on MRI

HIDE

Prev Next

Interactive Transcript

Pro Tip: Click on a word in the transcript to jump to that point in the video

0:00

Knee anatomy,

0:02

cruciates the PCL on MRI.

0:05

Let's return to the coronal projection for a moment to see where we are.

0:09

We're down low at the insertion.

0:12

There is the insertional footprint of the PCL.

0:14

It's fairly broad.

0:16

There is a medial bundle, a posteromedial

0:19

and an anterolateral bundle.

0:21

This patient does not have a very prominent meniscofemoral ligament

0:26

of wrisberg, which is not uncommon seen in about 20% of individuals.

0:31

Before we scroll the axial, which is probably my least favorite projection

0:35

for the PCL, let's scroll the coronal for a moment.

0:38

I want to show you one other thing.

0:40

Look at the inferior fibers of the PCL.

0:43

We've got our medial bundle and our lateral bundle.

0:46

But these inferior fibers may sometimes separate out and produce

0:51

some confusion for when they're really separate. This structure right here may be

0:56

confused with a loose body or a bucket handle tear.

1:00

Now let's scroll back and forth.

1:02

The way to avoid this pitfall is to follow the fibers back up to the PCL.

1:07

Separate.

1:09

Together.

1:10

Separate.

1:11

Together.

1:12

Now, let's turn our attention back to the axial.

1:15

We're going to ride our PCL from posteroinferior to anterosuperior.

1:21

We're below it, all bone.

1:24

Now the insertion.

1:27

And now let's ride it forward.

1:29

Let's keep going.

1:31

Here's the PCL, which is a more rounded, thicker structure in cross-section.

1:37

The ACL, more linear.

1:39

It's along the inner wall of the medial femoral condyle.

1:42

And there is the very broad footprint of the PCL, which is complex and broken

1:47

down into 16 zones or regions, which is far beyond what we want to discuss today.

1:52

But do remember that the PCL is fatter, more round, more bulky than the ACL.

1:58

And because of its configuration, in which the medial fibers and the lateral

2:03

fibers may turn or twist or cross between each other, the PCL, when it tears is going

2:09

to tear more often interstitially like this, and it'll blow up like a balloon.

2:16

Whereas the ACL, which is more like

2:19

a celery stalk configuration, more parallel, will often tear with a cut like this.

2:28

Now, if the PCL is cut and separated, you have to be worried about a more serious

2:33

catastrophic injury, including a knee dislocation or a complex pattern of knee

2:38

injury, or potentially a fracture in the posterior aspect of the tibia.

2:44

So different appearances of the tears, the PCL and ACL based on anatomy.

2:50

Let's move on, shall we?

Report

Description

Faculty

Stephen J Pomeranz, MD

Chief Medical Officer, ProScan Imaging. Founder, MRI Online

ProScan Imaging

Lesson

MRI Mastery Series: Knee Pre Course Activities

Lesson

Knee - Anatomy of the Supporting Structures

Lesson

Supporting Structure Anatomy: Focus on the Posterior Corners

Lesson

Case Review: Supporting Structure Injuries

Lesson

Meniscus MRI

Lesson

Pivot Shift Injuries and Meniscal Pathology

Lesson

More Meniscus Tears with Case Examples

Lesson

Applying What You've Learned

PCL: Axial on MRI