PCL: Axial on MRI
HIDEInteractive Transcript
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?
Stephen J Pomeranz, MD
Chief Medical Officer, ProScan Imaging. Founder, MRI Online
ProScan Imaging
© 2024 MRI Online. All Rights Reserved.