0:00

The next case is a 30 5-year-old man

0:02

with bright knee injury while snowboarding,

0:04

uh, one day prior.

0:06

And again, we're gonna go from medial to lateral.

0:10

So, uh, right off the bat I see that there's this edema and,

0:13

and these, um, medial supporting structures.

0:16

This MCL, you can see that, uh, there's, there's fluid

0:20

where it, it should attach a bone.

0:22

And this corresponds, oh, oh, yeah, this is the, um,

0:25

this coronal, uh, what had they had motion.

0:27

So here's the propeller.

0:32

And so there's, um, a complete tear of the, uh,

0:35

medial collateral, uh, ligament.

0:36

This is the superficial portion,

0:37

otherwise known as the tibial collateral ligament.

0:39

It's torn at the femoral attachment.

0:41

The deep medial meniscal femoral, uh, ligament is also torn.

0:45

And so this, uh, MCL is torn, uh, on the sagittal.

0:48

You can appreciate that.

0:49

There's also signal, increased signal, um, at

0:52

where the posterior oblique ligament is.

0:54

And this is a triangular shaped ligament.

0:57

And as we go, uh, posterior to the

1:02

tibial collateral ligament attachment,

1:03

you can see this posterior oblique, um,

1:05

ligament attachment is also, uh, abnormal.

1:10

Now, going back to the sagittals, as we scroll lateral,

1:15

you can see the body of the medial meniscus here.

1:17

We're getting into the, uh, posterior horn.

1:19

Um, there's no increased signal in this area.

1:23

And so this, uh, ramp area looks okay,

1:26

but notice that there's, um, abnormal alignment.

1:31

The medial tibial plateau is slightly anteriorly sublux

1:34

relative to the medial frontal condyle.

1:35

And there's gapping of this, uh, joint space.

1:38

As we keep going.

1:42

You can see the PCL is here.

1:44

The ACL is completely torn at the proximal attachment.

1:49

And as we get towards the, uh, next slice,

1:53

you start seeing the posterior root of the lateral meniscus.

1:56

And this entire area is, is quite abnormal.

2:00

So the, you can see the tibial attachment of that, uh,

2:03

posterior root, and there's some

2:05

fibers that are, that are still there.

2:07

But there's a, a, a gap here between the posterior root

2:11

as it attaches to the lateral meniscus.

2:17

And in this case, uh, there was a ligament of Humphrey

2:20

as well as a ligament of berg.

2:22

And all of them are discontinuous as they,

2:27

uh, all, uh, both of those meniscal femoral ligaments,

2:30

as well as the, uh, posterior root

2:32

of the lateral meniscus are all discontinuous

2:33

as they meet up with the, the,

2:36

the lateral meniscus, uh, proper.

2:39

And you can see that there's, um, extrusion of this, uh, uh,

2:44

lateral meniscus.

2:45

And here you can see nicely on the coronal

2:50

where there's this, uh, gap here.

2:53

You can usually appreciate

2:54

that quite nicely on the axial as well over here.

2:59

And in, in this case, there was also posterolateral,

3:04

uh, corona injury, uh,

3:08

including the antola ligament.

3:10

This will be covered in subsequent days.

3:11

I, so given all of the structures

3:15

that were disrupted in this case, the, uh,

3:17

surgery was much longer than,

3:19

than your typical arthroscopic surgery.

3:21

This thing took, uh, four to five hours with the number

3:24

of things that they had to repair.

3:27

Um, but focusing on the posterior root

3:28

of a lateral meniscus, you can see that, um, this is the,

3:32

uh, arthroscopic correlate.

3:34

Uh, this is the posterior horn of the, uh, lateral meniscus,

3:37

the lateral femoral condyle that would be, uh,

3:40

interrogating this area over here.

3:43

And you can see the disrupted margin of the, um,

3:46

posterior root of that lateral meniscus.

3:51

And this is the retrograde drill from

3:53

that transtibial pullout repair

3:55

and the final product, uh, with three sutures.

3:59

So, uh, this was already covered,

4:01

but the posterior root of the lateral meniscus, uh, there's,

4:04

uh, short and long fibers

4:06

and, um, there's been studies that have been, uh, performed.

4:09

There's, uh, uh, of all the root ligaments,

4:12

this has the most variable, um, sized, uh, area.

4:16

Um, some only, some studies only report the shorter fibers,

4:19

and in fact, that's where they do their repairs.

4:21

And so that's the only, that's the most important portion.

4:25

We had looked at this, uh, with high resolution MRI before

4:28

and on a sagittal oblique image through the posterior horn

4:31

of lateral meniscus, at least of this, uh,

4:32

cadavers that we looked at.

4:34

We noticed only, uh, one attachment.

4:37

So very, one, one large footprint.

4:39

But that footprint had, uh, short fibers and long fibers,

4:43

but it was just, uh, one big footprint.

4:45

And so, uh, that's generally

4:46

what I consider just one footprint with short

4:48

and long fibers.