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0:29

Today. We are honored to welcome Dr.

0:31

Rodrigo Aguiar for a lecture entitled MRI of ACL Terrace.

0:35

Dr. Aguiar completed his radiology residency at the Federal

0:39

University of Piana, Brazil,

0:41

an MSK imaging subspecialty training at U-C-S-D-E-U-A.

0:46

He is on the MSK staff at D-A-P-I-P-R

0:49

and professor of Radiology at Hospital Desk Clinicas,

0:52

federal University of Piana.

0:55

At the end of the lecture, please join Dr.

0:57

Aguiar in a question q

0:58

and a session where he will address questions you may

1:01

have on today's topic.

1:02

Please remember to use the q

1:04

and a feature to submit your questions so we can get to

1:06

as many as we can before our time is up.

1:09

With that, we are ready to begin today's lecture. Dr.

1:12

Aguiar, please take it from here. So,

1:15

Today we are gonna talk about the lesions, the, the, the,

1:19

the, the, how can, we can evaluate the, the, the ACL,

1:24

the lesions of the anterior cruciate ligament.

1:26

And just to give you a notion

1:29

or, uh, where, from where I'm speaking, I'm speaking

1:32

for this place here, uh, city of kci,

1:34

but the south part of Brazil.

1:36

So it's not like this, right? Uh, I'm not on the beach.

1:40

Uh, the good weather in Brazil in is in this

1:44

area right here, right?

1:46

I am in the south part of the country that looks

1:49

like this picture here.

1:50

By the way, this is a picture of, uh, famous park, uh,

1:54

of my city in the winter.

1:56

So we, we look, uh, my city looks more like, um,

2:02

a city from like, Argentina, Uruguay, than a city

2:06

for a city from Brazil, that you, maybe you have some idea

2:10

that this is all about Brazil.

2:13

But here's where I'm, uh, speaking from Ric Chiba,

2:17

by the way, that's great for work.

2:20

'cause, you know, the cold weather pushed us to work,

2:24

and, uh, you don't have like, time, uh, or beach, uh, to go.

2:29

So that's the place where I'm talking, uh, to you today.

2:34

So, uh, talking about the anterior cruciate ligament, uh,

2:38

the ACL is one

2:39

of the most common common damaged ligament of the human body.

2:43

Some papers, they, they, they, they, they describe,

2:46

that's the most common ligament.

2:47

That's, uh, that's thorn. But I, I don't know.

2:50

I think that like the anterior tail fibular ligament,

2:53

you know, uh, at the ankle, uh, it, it gets like, uh,

2:57

the first place, not the ACL,

2:59

but it's a very commonly, uh,

3:02

damaged ligament of the human body.

3:04

It can lead to meniscal and chondral lesions,

3:07

and finally to osteo osteo aosis osteoarthritis.

3:12

And the majority of the, uh, knee ligament surgeries

3:17

are surgeries about the anterior cruciate ligament.

3:20

So that's why we need to know more,

3:22

and we need to give the correct diagnosis of an ACL tear,

3:26

uh, when we are evaluating an MRI of the knee,

3:30

and according to this paper here, for example, uh,

3:35

100 to 200,000 ACL injuries,

3:39

they occur annually in the us, for example,

3:42

and the monetary burden of the,

3:46

the ACL lesions or the ACL tear, it's about the direct

3:51

and the indirect costs.

3:53

Uh, it's about $7 billion annually just in the us.

3:58

So, uh, uh, there is a lot of, uh, uh,

4:02

things on the table when you, when you talk about ACL

4:06

and we are evaluating, uh, the ACL ligament, right?

4:10

So talking about a, a little bit about the anatomy,

4:13

the biomechanics of the ligament.

4:16

So, uh, first about the functions of the ACL, uh, eh,

4:20

the ACL is the primary restrictor

4:23

of the anterior tibial translation.

4:25

It's a secondary restrictor of the internal tial rotation.

4:29

Rotation, particularly the posterolateral band, right?

4:33

The acl, uh, it's formed by, let's say,

4:36

there is some controversy in the literature,

4:39

but, uh, general, generally speaking, the most common, uh,

4:42

knowledge today is that the ACL is formed by two bundles,

4:46

the endometrial bundle and the poster lateral bundle,

4:49

and the posterolateral bundle.

4:51

It's, uh, it works also as a secondary restrictor

4:55

of the internal tibial rotation.

4:57

Another function of the ACL is that the ligament, uh,

5:01

it works as a secondary restrictor of the vagus

5:04

and virus of the knee, especially when the

5:08

collateral ligaments are torn.

5:11

So, talking about the bundles of the a c,

5:13

the two bundles of the ligament.

5:15

Here, you can see these two bundles in this draw,

5:18

in this drawing, the inter medial bundle

5:20

and the post lateral bundle, the femoral footprint

5:24

of the ACL has a vertical direction,

5:27

and the tibial footprint has a horizontal direction.

5:30

So, uh, the ligament has a rainbow like appearance,

5:34

or it tweets around its own ax

5:38

because of this different, uh, directions

5:41

of the femoral footprint and the, uh, the,

5:44

and the tibial footprint.

5:45

And that's good, right?

5:47

Uh, the ACL, it can, uh, bears

5:49

or it can stand more, uh, uh, more load

5:53

because of this configuration

5:55

that I'm showing here in this drawing.

5:57

So, the anter medial bundle, uh, put that in mind, right?

6:01

That's important. And I'm, I'm gonna show you that, uh, in,

6:04

in on the MRI in a moment, the, an medial bundle, it has,

6:09

uh, uh, upper,

6:11

in an anterior origin at the femoral footprint in comparison

6:15

to the post lateral bend.

6:17

Okay? So, and this is the, this is the way

6:21

that we see the MRI of the knee.

6:23

So that's why I'm showing, I'm showing you this, uh,

6:26

configuration of the femoral footprint

6:28

with the knee in extension.

6:30

For example, when the atropic surgeon, uh, uh, uh, it go

6:34

to a arthroscopy, for example, the knee is not in extension,

6:38

and this relationship, it is different.

6:41

But I'm showing this relationship in extension

6:44

because that's the way that we

6:46

evaluate the MRI of the knee, right?

6:48

So here is, so this is the femoral footprint

6:51

of the ACL are talking about the tibial footprint

6:54

of the ligament, the inter medial band bundle.

6:59

It has a inter medial insertion.

7:01

That's why it has it, uh, this name

7:04

and the poster lateral band,

7:06

it has a post lateral insertion, right?

7:09

And I'm talking, I'm gonna talk in a minute about an

7:12

important relationship between the anterior, uh,

7:16

root ligament of the lateral meniscus

7:18

and the ACL, particularly the posterior lateral band they

7:23

insert together, uh, at least in some percentage.

7:27

At least in some part. Okay?

7:29

So, talking about the femoral, uh,

7:31

the tibial footprint right now.

7:32

So here is the, in this drawing here, here's the area

7:36

of the tibial footprint of the ACL,

7:39

and this is the area of the tibial footprint

7:44

of the anterior, anterior, uh, root ligament

7:48

of the lateral meniscus.

7:50

And you, we can see that they share a common area of, uh,

7:55

of footprint in this region right here.

7:57

So keep that in mind.

7:59

Some pitfalls that we see on the ACL in the ACL, on the MRI

8:04

of the ACL, and on the MRI of the anterior, uh,

8:07

root ligament of the lateral meniscus meniscus, it happens

8:11

because of this common, uh, footprint that they share, uh,

8:16

on, on, uh, on the tibia.

8:19

So, uh, the inter medial bando of the ACL, it, uh,

8:23

inserts more anteriorly

8:24

and me, me, medially on the tibial footprint

8:27

and the poster lateral band.

8:29

It inserts more posteriorly

8:31

and laterally, uh, on this, uh, tibial footprint.

8:35

And talk a little bit about the location

8:38

of the ACL in relation to the capsule

8:42

and to the synovia.

8:44

This is an important point.

8:45

The ACL is, uh, intracapsular ligament,

8:49

but is extra synovial, right?

8:52

The si the syn synovial fluid, it doesn't touch

8:57

directly the fibers of the ACL.

8:59

And that's important because, uh, in case of ACL tears,

9:02

for example, that the synovial fluid, it touched the fibers

9:07

of the ACL, it, uh, preclude it, uh, uh,

9:11

impair the normal healing of the ligament.

9:14

So the, uh, synovial membrane, it works as a protector

9:18

of the anterior cruciate ligament.

9:21

And when the synovial membrane is torn in, like in case of,

9:25

uh, ACL tears, for example, uh, this contact

9:28

of the synovial fluid with the ACL, it's, uh, it, it, it,

9:33

it, it, it, it doesn't let the ligament, uh,

9:37

heal by itself.

9:39

So, uh, this intracapsular,

9:42

but astro synovial, uh, configuration, it's similar

9:46

to the long head of the biceps, the syn novo membrane.

9:49

It's important to protect and to regenerate the ACL

9:54

and the vascularization of the ACL.

9:57

It comes from, uh, this, the, uh,

10:00

posterior artery right here, the geniculate artery that, uh,

10:06

uh, va vascularized the, uh, uh, posterior, uh,

10:11

crochet ligament and the anterior crochet ligament.

10:13

Right? So, let's see some images of the MI, uh,

10:18

of the ACL on the MRI, right?

10:20

So here, uh, we can see the anatomy of the ACL,

10:23

the two bundles, uh, the, the two bands.

10:26

We can see these two bands right here.

10:27

So this is the axial plane. In this axial plane.

10:31

Here is the beginning of the intercondylar notch, uh,

10:35

at the posterior femur.

10:37

So these first fibers that we see here, these are, uh,

10:41

uh, fibers.

10:42

The inter medial bundle from the inter medial

10:44

bundle of the ACL.

10:46

These are fibers of the inter medial bundle.

10:48

This second fibers here, that's more inferior,

10:52

inferior, and posterior.

10:53

These are fibers of the posterior lateral band.

10:56

So we can see these two bands on the MRI of the knee.

10:59

Most of the time. We can, uh, differentiate

11:03

between the inter medial, uh, band

11:05

and the poster lateral band here in the coronal plane.

11:08

Same thing. This is the inter medial band of the ACL.

11:13

This is the posterolateral band of the ACL.

11:15

We can see these two bands.

11:17

They go, uh, up here to the,

11:21

to the posterior and superior portion

11:24

of the intercondylar notch at the femur.

11:27

And they, uh, at the, uh,

11:28

at the femoral footprint right here.

11:30

So we can see the, the two bundles of the ligament.

11:33

Notice the closed relationship between

11:36

the posterolateral bundle right here

11:38

and the anterior root ligament

11:41

of the lateral meniscus, right?

11:43

I'm gonna show this in a better image in a moment. Here.

11:47

We can see this, uh, this is a coronal oblique of the ACL.

11:51

So you can see the inter medial band right here, right?

11:55

This is the intermediate band, uh, femoral footprint,

11:59

tibial footprint of the leg of the band.

12:01

And this is the intermediate band,

12:03

and this is the poster lateral band.

12:06

And notice that the insertion of the tibial insertion

12:10

of the poster lateral band, it comes together

12:13

with the anterior root ligament

12:15

of the lateral meniscus right here, right here in this area.

12:20

So this is the, an Miral band,

12:22

and this is the posterolateral band.

12:24

And we can see these two bands in almost all

12:29

MRIs of the knee.

12:30

Okay? This, uh, the s plane, it's a good plane

12:34

to evaluate the direction of the fibers,

12:38

but it's not a good plane to, uh, separate

12:41

the inter medial band

12:42

and the post lateral band here, you can see

12:44

this fi fibers here, probably of, probably the,

12:49

an medial band.

12:50

And here, more posteriorly, uh, these

12:54

probably are the fibers of the poster lateral band,

12:58

I'm sure about the, about this, uh, about the, the, the,

13:03

the, the, the morphology right here,

13:04

because I compared with the other planes.

13:08

So when I'm showing these images right here for you, it's

13:12

because I, I, I did a, a, a cross section

13:16

with the other planes to be sure

13:18

that this is the intermediate band,

13:20

and this is the poster lateral band, right?

13:23

But the Sal plane, it's a great plan to

13:27

evaluate the direction of the ACL

13:30

to see if the ACL is parallel to the blooming sat line.

13:34

That's important. That's an important anatomical mark to

13:38

evaluate, to see, uh,

13:39

if the ACL is okay on the MRI of the knee.

13:43

So about the mechanisms of lesion.

13:45

So we, we talked about the anatomy a little bit,

13:49

about the biomechanics of the ligament,

13:52

but now let's talk about the mechanisms of lesion.

13:54

That's important because if we know the mechanisms

13:58

of lesion, we can, uh, uh, we can, like, uh,

14:02

we understand the main lesions, and we can look, uh,

14:06

and look for these main lesions when we see some, uh,

14:11

patterns of bone marrow contusions, for example.

14:14

So, let's talk about the mechanisms of lesion right now,

14:17

and, uh, uh, talking about the mechanisms

14:22

of lesions of the ACL.

14:24

Uh, the direct trauma, it's responsible for 20 to 58%

14:29

of the ACL tears.

14:30

And the indirect trauma is, uh, it's even more important.

14:35

It's, uh, responsible for 42 to 80%

14:40

of the ACL tears depending, uh, on the, the literature

14:44

that you are seeing, that you are studying.

14:47

So talking about the mechanism of e lesion,

14:49

this is the main mechanism of lesion of ACL.

14:53

Tears is the PIVO shaped mechanism of lesion, also known

14:57

as the valgus knee collapse.

15:00

And, uh, how this lesion happens, uh,

15:04

generally speaking, the foot is, uh, stuck on the ground.

15:08

And, uh, there is a v of, uh, semi flexed knee

15:13

with internal rotation of the femur

15:15

and external rotation of the tibia.

15:18

Okay? When, uh, with an axi load, uh, all,

15:22

all of this, uh, uh, all, all of this loads,

15:26

they come together, all of this, uh, uh,

15:30

situations come together.

15:32

And, uh, there is also, uh, a quadriceps anterior traction.

15:36

And when it happens, uh, there is a tear

15:39

of the anterior cruciate ligament.

15:41

It generates a tear of the anterior cruciate ligament.

15:44

And when it happens, the first thing that, uh, occurs, uh,

15:49

is, uh, anterior translation of the tibia, and the,

15:54

and the lateral bone os the, the lateral contusions

15:57

of the lateral bone, OSUs contusions, they occur.

16:00

So we see edema on the

16:03

femoral condyle on the, like in the central part

16:06

of the femoral condyle,

16:07

and the posterior portion

16:09

of the tibial pla lateral tibial plateau.

16:12

So these are the contusions of the pivotal shift mechanism,

16:16

the first impact, or the cup lesions,

16:19

because, uh, remember the lesion, uh, this mechanism

16:23

of lesions occurs with vs.

16:25

Of the knee. So that's why the lesions, they happens,

16:29

or they occur first at the lateral side,

16:31

because the medial side is open.

16:33

So the lesions they occur, the bone, uh, lesions,

16:36

they occur at the lateral side.

16:38

After that, the tibia, uh, will come back

16:42

to its normal place.

16:43

But when it come back to its normal place, uh, this, uh,

16:48

this valgus, it's hyper corrected, let's say

16:51

that it's hyper corrected.

16:53

And we can, uh, have lesions at the medial portion

16:57

of the femur and the medial portion of the tibia.

17:02

So we have the medial ulcer contusions,

17:05

or the countercoup lesions.

17:07

So these are, uh, that's why, uh, the lesions of, uh,

17:11

the bone marrow edema, uh,

17:13

they occur at the people shaped mechanism of the a c tear.

17:16

And that's the way that we, uh, we'll see the,

17:20

the bone marrow contusions on the MRI of the knee.

17:23

Here we can see a lesion, a complete tear

17:26

of the anterior cruciate ligament, right here and here.

17:29

This is the later of Hedy.

17:31

This is the later of tibial plateau.

17:33

And we can see the bone marrow, uh,

17:36

edema at the central portion of the lateral femoral condyle.

17:41

And this other bone marrow edema with a contusion fracture,

17:45

with an impaction fracture right here at the posterior

17:49

margin of the lateral, uh, tibial plateau.

17:53

These are like, uh, uh, the hallmark of the,

17:56

the people shift lesion.

17:58

Every time that you see this pattern

18:01

of bone marrow edema at the lateral compartment of the knee,

18:05

you, you, you should, uh, go

18:08

after, uh, the, uh, a lesion

18:11

of the anterior cruciate ligament.

18:12

It should go after, uh, the lesion

18:14

of the anterior cruciate ligament,

18:15

because this is the pattern of the p shift mechanism, uh,

18:19

the bone marrow edema.

18:21

And if the lesion, it's like the, the, the, the, the,

18:24

the force, it's, uh, higher enough.

18:27

We can also see lesions at the la at the medial portion

18:31

of the, the knee.

18:32

So here at the medial femoral condyle,

18:35

we can see this bone marrow edema at the central portion

18:38

of the medial femoral condyle,

18:39

and also on bone marrow edema at the posterior portion

18:44

of the medial, uh, tibial plateau.

18:46

Okay? By the way, this bone marrow edema at the posterior

18:49

portion of the medial tibial plateau,

18:53

it's also a marker of a very, uh, common lesion

18:59

of the posterior horn, of the medial meniscus.

19:02

That can happen, uh, that can happen with an ACL tear

19:06

that is at the ramp lesion.

19:09

So when you see this edema at the posterior portion of the

19:13

video uht plateau, you should, uh, you should,

19:18

uh, double increase the suspicion of, uh, ramp lesion,

19:23

uh, the posterior horn of the medial meniscus.

19:26

Uh, uh, the ramp lesion is another lecture.

19:29

Uh, there is a lot of things to,

19:31

to talk about the ramp lesion

19:32

and other lesions that can occur together with the lesion

19:35

of the anterior crucial ligament.

19:37

I'm not going over this today.

19:39

Today is just about the anterior cruciate ligament.

19:42

So let's continue talking about that.

19:45

Here in the axial plane.

19:46

You can see the patterns

19:48

of the bone marrow contusion at the femoral,

19:51

at the lateral femoral, uh, condyle,

19:53

and the lateral tibial plateau.

19:55

Here are the patterns

19:57

of the bone marrow contusion at the medial femoral condyle

20:01

and the medial tibial plateau right here.

20:03

And here is the complete air

20:06

of the anterior cruciate ligament that we can see, uh,

20:10

very well in this case here.

20:12

Well, uh, another mechanism of lesion that I want to

20:17

talk to you about, the lesion of the,

20:20

the anterior cruciate ligament is the

20:22

hyperextension mechanism, right?

20:23

Because everybody knows

20:25

that the hyperextension mechanism is the mechanism of lesion

20:29

of the PCL tear of the posterior cruciate ligament,

20:32

but it is also a very important mechanism of lesion

20:38

of the anterior crucet ligament.

20:40

So, uh, I, I see many cases in a day in our

20:46

weekly basis, uh, of patients with, uh,

20:49

anterior cruciate ligament tear with, uh,

20:52

hyperextension mechanism of lesions.

20:55

So keep that in mind, the hyperextension mechanism.

20:58

It can cause tear of the posterior cruciate ligament,

21:01

but it can also cause tears

21:02

of the anterior cruciate ligament as well.

21:05

So, uh, in this type of, uh, mechanism,

21:10

the bone mar edema is different from the

21:14

vo shift mechanism of lesion, the bone mar edema,

21:17

it occurs at the anterior portion of the hemon

21:21

and the tibial plateau, uh,

21:23

because of the hyperextension mechanism of lesion.

21:26

So, and this is well known as the kissing lesion,

21:30

because that's what happens right here, uh, by the way,

21:34

with the people shift mechanisms,

21:35

it's also a kissing lesion, but the, it's a kissing lesion,

21:38

uh, during the mechanism of lesion when the bone

21:40

and the, the bones are in different positions, right?

21:43

But with the hyperextension mechanism, they stay, uh,

21:47

the bones, they stay at the, almost the same position.

21:50

So it's very easy to see the relationship

21:53

between these two areas of bone marrow edema.

21:56

So this is the classic kissing lesion.

21:59

Uh, just so keep in mind

22:01

that the anterior crucial ligament hyperextension mechanism

22:04

is also, uh, uh, a type of mechanism

22:08

of lesion of this ligament.

22:11

So, uh, this is a very nice paper talking about the bone

22:15

marrow contusion patterns of the knee, uh,

22:17

from the radiographics for 2000.

22:20

And, but one thing that I'm Brazilian, right?

22:23

So I understand something about soccer, okay?

22:26

And, uh, something that, uh, that, uh, when I,

22:31

I saw, I, I saw this paper, uh, one drawing that, uh, that,

22:36

uh, keeps my attention was this drawing here about a

22:40

patient, like a, a player kicking the ball

22:43

and doing a next, uh, a hyperextension of the knee.

22:47

But that's not the way that happens really, in the,

22:50

so in soccer with soccer players,

22:52

or almost in all other, uh, uh, sports,

22:58

uh, what happens here is the, uh, that's the kind

23:02

of the mechanism of lesion.

23:03

The play is kicking the ball.

23:05

And some part of the open op opponent player blocks the

23:09

movement of the, this play that's kicking the ball.

23:12

So when the, like in the, in this example,

23:15

when the thigh is blocked, so the leg, it can hyperextend.

23:21

So this is the hyperextension mechanism that causes, uh,

23:25

ACL tears, maybe PCL tears in athletes,

23:28

in soccer players, for example.

23:30

And so that's what this part here is the part

23:34

that was missing in this paper here

23:36

to make sense about the hyperextension mechanism of lesion.

23:40

So this is the way that, uh,

23:42

causes the hyperextension of the knee.

23:43

This is the original, uh, drawing of the paper, right?

23:48

So it's like, uh, for us that understand soccer, eh, we,

23:53

I couldn't understand how this could happen with a, like,

23:56

professional or soccer player.

23:58

But what happens is this, is this something blocks the fight

24:03

of the player, so it causes the hyperextension of the leg.

24:07

So this is an example of a hyperextension mechanism that,

24:11

uh, ca caused a tear

24:14

of the anterior cruciate ligament right here.

24:16

So we can see this bone marrow edema at the anterior portion

24:19

of the medial femoral condyle in the medial tibial plateau.

24:24

Here we can see the complete air

24:26

of the anterior cruciate ligament.

24:29

And one thing that I, I've seen a lot is that, uh, some part

24:34

or, uh, uh, uh, big part of this hyperextension mechanism

24:37

of lesion, uh, the lead, the vector is not straight,

24:41

like anterior posterior.

24:42

It's something diagon diagonal, like, uh,

24:45

and I'm gonna show you this example here for, uh, we can see

24:49

the, the, the kissing lesion at the anterior portion

24:53

of the medial femoral conia at the anterior portion

24:56

of the medial tibial plateau.

24:58

And look here at the posterior, at the post lateral corner

25:02

of the knee, we can see a complete tear of the,

25:06

of all structures of the post lateral corner of the knee,

25:10

including, uh, a fibular fracture right here, okay?

25:15

Caused by this hyperextension mechanism of lesion

25:19

that was somewhat diagonal,

25:22

and it damaged the,

25:24

the anterior cruciate ligament right here.

25:27

And also, uh, the post lateral coronary of the knee.

25:31

So this was like, this was the vector.

25:34

The vector of this hyperextension mechanism

25:36

of lesion was not a straight, an posterior vector like this.

25:40

It was some diagonal from medial to lateral.

25:43

So it caused the rupture of the anterior cruciate ligament

25:46

and the lesion, the, the rupture of all the structures,

25:50

basically, of the postal cord of the knee.

25:53

So that's about the, uh, the first part

25:58

of this lecture,

25:59

and about, uh, about the anatomy, about the biomechanics,

26:03

and about the mechanisms of lesions of the ACL.

26:07

So now we can go, uh, let's go to the lesions right here,

26:12

and we can, uh, I can explain you better, uh, the, the me,

26:17

the, the patterns of the, of the imagery of the, of the,

26:21

of the anterior cruciate ligament tear and, and so on.

26:25

So first, let's talk about, uh, the strain

26:28

and partial tears of the anterior cruciate ligament, right?

26:31

Not the ariat.

26:32

Let's start with big steps,

26:34

talking about the strain and partial tears.

26:37

So, uh, when we, uh, when the patient has a strain, uh,

26:42

of the ACL, uh, what happens, uh, on the MRI is

26:46

that we can see a high signal intensity inside the ligament,

26:50

but without discontinuity, discontinuity

26:53

of the ligament, right?

26:54

So it can be challenge sometime challenging sometime

26:58

to distinguish between, uh, a strain

27:01

of the a CA lower grade partial tear of the acl.

27:04

Sometimes it's difficult to make this, uh,

27:07

this call if it's a strain or lower grade partial tear.

27:11

The good news is the bottom line,

27:13

both lesions are treated clinically.

27:16

You are gonna start the, the toic surgeon.

27:18

Uh, they will treat these lesions clinically first.

27:22

Um, if there is no, uh, instability, if,

27:28

to be frank, it doesn't matter to that much

27:30

to the orthopedic surgeon, uh, in our older pa uh, patients,

27:34

we have to keep in mind that the degenerative chains

27:39

of the ACL, okay, uh, if we are seeing, uh, uh,

27:43

on high signal intensity within the anterior cruciate

27:48

ligament without discontinuity discontinuity in a older

27:51

patient, especially if this li if the ligament is thickened,

27:55

we with no history of trauma,

27:57

we should think about the generalship change.

28:00

Okay? Uh, things get nasty when, uh,

28:04

older patient has, uh, trauma, right?

28:06

Because, so it's a little bit harder

28:09

to define if you are seeing like a string, uh,

28:14

uh, low grade partial tear

28:16

or degenerative change of the ligament.

28:18

But generally speaking, it's just a very, uh,

28:22

little percentage, uh, of patients that we see with lesions

28:27

of the anterior cruciate ligament.

28:28

But keep that in mind.

28:29

Keep, uh, things can be a little bit nasty when we see, uh,

28:34

traumatic lesions in older patients.

28:37

And here is an example of, uh, a pa a patient with, uh,

28:42

with a knee torsion,

28:45

with high signal intensity within

28:47

the anterior cruciate ligament.

28:48

But we can see that the fibers are preserved.

28:51

There is no discontinuity of the fibers.

28:53

We can see that in the S plane. It's not the best plane.

28:56

See at the Corona plane here, we can see at the Corona plane

29:00

that the fibers are still here.

29:02

There is no rupture, there is no tear of the ligament.

29:05

Here is the coronal bleak plane that we can see

29:09

the anterior cruciate ligament right here.

29:11

High signal intensity, high signal

29:13

intensity inside the ligament.

29:15

But there is no discontinuity of the two bundles.

29:18

The, uh, an medial bundle

29:20

and the post lateral bundle, the two bundles are here.

29:24

Um, there is no, this, uh, it doesn't seem to be, uh,

29:28

partial tear of the ligament.

29:30

And talking about the partial tears of the ACL, uh, we can,

29:35

the, the clinical

29:36

and the radiological diagnosis

29:39

of the partial tear can be difficult, right?

29:41

It can happen in 10 to 28% of case of ACL tears.

29:46

They are partial tears.

29:48

Uh, the patient are, uh, generally speaking, uh, he

29:52

or she has less instability, uh, bone marrow lesions

29:57

or the bone lesions that I've, uh, I, uh,

30:00

I just show showed you, uh, a few minutes ago.

30:03

They are less frequent.

30:04

We in patient, uh, uh, with patients with partial tears,

30:08

probably the, the, the, the mechanism of trauma, the force

30:13

wa is, was lower.

30:14

The load was lower than to with patients

30:19

with, uh, complete tear.

30:21

And, uh, uh, one thing that is, uh, uh, important

30:26

to know is in, is that, is that in a flex, the knee,

30:29

the tension is higher in the inter medial band.

30:33

So the intermediate band, it works with the knee inflection.

30:37

And when the knee is flexed, there is a higher chance

30:40

to rupture, let's say first the intermediate band,

30:44

when the knee is extended or prox,

30:47

or very close to the extension, uh, the band

30:51

that is, uh, can be compromised.

30:55

First is the post lateral band.

30:58

So the post lateral band, uh, the in extended knee,

31:02

the tension is higher on the post lateral band.

31:05

And remember, the post lateral band is also important

31:09

for the rotator stabi stability.

31:12

Uh, the medial rotatory stability of the knee, okay?

31:15

The inter medial band,

31:17

it's more just about the, the anterior draw.

31:21

But the post lateral band, it also works.

31:24

It also, uh, has its function as, uh, a stab,

31:29

a stabilizer of the medial, uh, rotation

31:33

of the, of the knee.

31:35

So let's see this case here.

31:37

Uh, a case of partial tear of the poster lateral band. Okay?

31:41

So here we can see the

31:45

inter medial band is this band right here, okay?

31:49

We can see the femoral insertion right here,

31:53

and the chibo insertion of the endometrial band right here.

31:57

But the postal band is totally blurred.

32:00

We can't see the, the band right here.

32:03

It's, uh, or it's obscured. It's blurred.

32:06

And when we, uh, evaluate the Corona OBL plane,

32:10

we can see the intermediate band right here,

32:12

the intermediate band,

32:14

but we cannot see the poster lateral band right here.

32:18

It's I irregular. It's not homogeneous. We just can't.

32:23

We just see very well the intermediate band right here.

32:26

So this is a, uh, partial tear of the, uh,

32:29

anterior cruciate ligament is the tear

32:31

of the poster lateral band here at the axial plane.

32:34

This is the intermediate band.

32:36

This is the intermediate band.

32:37

This is the intermediate band.

32:39

It goes from the femoral footprint to the tibial footprint,

32:42

right here, and here in the area

32:46

of the post lateral band.

32:48

We can't see the band right here,

32:50

the post lateral band right here.

32:52

So that's a partial tear of the anterior cruciate ligament,

32:55

the post lateral band.

32:57

Uh, in the clinical practice, I've seen more partial tears

33:02

of the post later band than the inter medial band, right?

33:07

And, uh, uh, the literature, they say

33:10

that the post lateral band, it's

33:13

somewhat more important than the inter medial band

33:16

because of this, uh, the, uh, the rotatory instability

33:21

that it provides in comparison to the inter medial band.

33:25

So here in the Sal plane, we can see the fibers

33:28

of the inter medial band right here,

33:30

and this high signal intensity, uh, in the area

33:33

of the anterior cruciate ligament.

33:35

But here, we cannot define, which is the intermediate band

33:38

and the postal band.

33:40

I'm just telling you that

33:41

because I can't see the intermediate band fibers in the

33:45

other, on the other planes, right?

33:47

That's why I'm talking to, I'm telling you

33:49

that this is the intermediate band,

33:52

and we cannot see the post lateral band.

33:55

So now let's talk about the complete tears, uh,

33:59

and about the complete tears, uh, at the MRI of the knee,

34:03

we have, we can see some direct findings of the ACL tear

34:08

and some indirect findings of the tear.

34:12

Okay? So the direct findings of the IACL tear, uh,

34:18

are, uh, le are images related to the

34:22

ligament lesion itself.

34:24

Uh, and the indirect findings are lesions related,

34:29

for example, with the mechanism of lesion

34:32

with the anterior draw of the femur of the tibia.

34:36

So this creates some indirect findings that can help us

34:41

to identify the ACell tear, or to be sure,

34:45

or to be more certain that we are dealing with a lesion

34:50

or insufficiency of the anterior ate ligaments.

34:53

So, uh, as I told you, uh,

34:57

the indirect findings are signs

34:59

of the ligament insufficiency, like the anterior draw

35:02

of the, of the tibia, and the mechanism of lesion.

35:05

So let's talk first about the direct findings, right?

35:09

Like, uh, the direct findings,

35:11

it's like we see the tear of the ligament.

35:13

So that is the direct finding that we try to, uh,

35:18

see, that we try to find, uh,

35:21

when we are evaluating the MRF knee.

35:23

So we can see, uh, ACL fibers discontinuity

35:27

with the, uh, the fibers can be irregular.

35:30

W uh, they're remaining, uh, the, the, the, the,

35:35

the, the fibers, uh, the proximal

35:38

or distal fibers of the ACL, they can become, uh,

35:43

have a wavy pattern because of the complete tear of the ACL.

35:48

Uh, and we can, you can see a high signal intensity

35:51

on the fluid sensitive sequences on the area

35:54

of the ACL tear.

35:56

Uh, another sign that we can see on the MRI

35:59

of the knee is the empty notch sign, uh, uh,

36:02

especially at the proximal third of the ACL.

36:05

Most of the time, the lesions of the ACL,

36:07

they are located at the proximal third, uh, uh,

36:10

about 70% of the time.

36:13

The lesions are, they occur at the proximal par

36:16

portion of the ACL.

36:17

And we can see this empty knot sign on the Corona plane,

36:21

and also on the Axo plane.

36:23

I'm gonna show you the, uh, this sign for you in one moment.

36:27

So, uh, the lesions of the ACL, they can, uh,

36:32

they can occur, uh, without the rupture

36:36

of the synovial membrane.

36:38

We call this, uh, intra synovial sheath, ACL tear.

36:43

So this kind of like, uh, complete tear, they tend to

36:48

preserve the, the direction of the ACL tear.

36:52

Even if the ACL is torn, uh, the direction can be preserved

36:56

because of the, the synovial, the,

37:00

the synovial sheath is not torn.

37:02

And sometimes you can see some healing of this type

37:07

of ACL tear.

37:08

It's r right? It's rare. It's not normal.

37:11

Oh, I can count on my fingers the case that, oh,

37:14

I'm gonna show you a case of this in a moment also,

37:17

but I can count in my fingers

37:19

how many cases I've seen about like intra synovial

37:23

shield, ACL tears.

37:24

That's not the usual.

37:26

The usual is this, it's a competitor of the ACL with, uh,

37:32

some kind of, uh, change of direction of the ligament.

37:37

Stu some, most of the time, the, this, uh,

37:40

the distal ligament stamp, it falls down,

37:42

it horizontals at the,

37:46

at the tibial plateau near the, the, the tibial plateau.

37:49

And sometimes you can see the inversion, uh, inversion

37:54

of the ligament stamp, uh, ligament stamp

37:57

and case like that.

37:59

We can, uh, it can cause an impingement of this stamp

38:04

and preclude the normal extension of the knee.

38:07

And I'm gonna talk about a little bit about

38:09

that in a few minutes.

38:11

Almost 70% of the ACL tears are proximal tears, right?

38:14

So keep that in mind. Also, here is the most common side

38:19

of meniscal of the ACL tear,

38:22

or the, at the femoral footprint,

38:24

or at the proximal third of the ACL.

38:27

These are like, uh, these two areas are like, they account

38:31

for more than 70% of the a l tears.

38:34

So here's an example

38:35

of a complete ACL tear at proximal third

38:39

of the ACL, very close

38:42

to the femoral footprint of the ligament.

38:44

Here you can see at the transaction

38:46

of the ligament here in the axial plane here in the coronal

38:50

plane, that's the area of complete a c tear right here.

38:54

You, we can see, notice that the, the distal stump,

38:59

it's getting more horizontal than normal.

39:02

Here's the blooming SAT line,

39:04

and the here, this is the, uh, distal stump

39:07

that it's getting more horizontal in comparison

39:11

to the normal ACL.

39:13

So here's the, uh, axial plane, the sagal plane,

39:16

fluid sensitive sequences.

39:18

Here is the DP sequence showing the

39:21

complete tear right here in this region.

39:23

And here is the Corona BL showing the complete tear

39:27

of the ACL in this region here, close

39:31

to the femoral footprint.

39:32

Here is another case.

39:34

Uh, sometimes the rupture is not well defined

39:38

as in this first case that I've shown, showed you.

39:42

Sometimes it has a more like, uh, they call,

39:46

uh, uh, the literature.

39:47

They call this a clown like appearance, right?

39:50

We can see that the ligament, uh, it's, uh,

39:54

it's not okay, it's irregular.

39:56

We cannot see the fibers,

39:58

but, uh, we cannot see the lesion, the, the, the, the,

40:03

the area of the lesion very well as the first case.

40:07

This is, uh, the, a clown like appearance of the ACL tear.

40:10

But here is the complete tear of the ACL.

40:13

Here's the, uh, TT two, uh,

40:16

s plane fluid sensitive sequence.

40:18

Here's the PD sequence showing the tear look, uh, notice

40:22

that the, the pro, the gal stump,

40:25

it's getting a little bit more horizontal,

40:28

but, uh, the, with this type of, uh, tear

40:31

with this cloud-like appearance, sometimes it's hard

40:34

to identify the stop

40:35

because everything is degenerated and torn,

40:40

and we cannot see the right.

40:43

Uh, the, the area of the, the,

40:46

the tear itself very well defined here is in the Corona,

40:49

the exo plane, this count, like appearance tear

40:53

of the ACL at the middle, middle, middle,

40:56

approximate middle third of the ligament is the area

40:59

that's more compromised here,

41:00

that the tear is in this region.

41:02

Here's the al plane showing the lesion of the ACL,

41:07

complete tear of the ACL, uh, going, uh, almost, uh,

41:10

until the, uh, distal third

41:12

of the ligament here in the coronal plane.

41:14

We can also see the complete tear of the ligament.

41:17

This cloud-like appearance.

41:18

Uh, we cannot see the ligament,

41:20

the fibers in the normal location right here.

41:25

And sometimes the ligament, the distal stop,

41:29

it can be averted,

41:30

and we can, uh, it can cause entrapment of this, uh,

41:35

distal, uh, stamp.

41:36

And it can, uh, preclude

41:39

or it can, uh, uh, it can be difficult for the patient

41:42

to extend the knee

41:44

because of this, uh, configuration of this migration

41:48

of the distal stamp of the ligament.

41:51

Look here, complete tear of the ACL.

41:53

And this is part of the, uh, averted st stump of the ACL.

41:58

But be careful, right?

41:59

Sometimes when we see this image here, we, you have

42:03

to check if the, uh, meniscus

42:06

or the meniscal, if they're okay,

42:08

because sometimes the image like this can be a meniscal

42:12

fragment, like, for example, a bucket handle tear.

42:16

So, uh, just don't, uh, if you see this image here, you have

42:20

to look for lesions of the menis, uh,

42:23

media meniscus, lateral meniscus.

42:25

See if the patient has a bucket handle tear.

42:29

Because most of the time, when you see,

42:31

when you see this type of, uh, image, here, you are dealing

42:34

with a, uh, a bucket handle tear

42:37

and not an averted, uh, ACL stump.

42:41

Okay? But keep that in mind.

42:43

So here in the, uh, the PD sequence,

42:46

we can see the ligament averted right here in this region.

42:50

This is the Corona plane,

42:51

the Corona oblique plane showing the complete tear

42:54

of the ACL and the area of the aversion

42:59

of the ACL stump.

43:00

Sometimes it can be

43:02

one di differential diagnosis can also be a

43:07

cyclops lesion, right?

43:08

Sometimes it looks like a cyclops lesion.

43:11

That is some kind of fibrosis after fibrosis.

43:14

That focal arthrofibrosis that can, uh, happen, uh,

43:19

in this region right here.

43:20

It can be par surgical.

43:22

Sometimes it's not par surgical,

43:24

but it's another differential diagnosis

43:26

that you have to keep in mind.

43:28

Okay? So talk a a little bit about the

43:33

intra shift there.

43:35

That, that I told you that it can, uh, heal.

43:38

And I'm gonna show a case when it happened.

43:43

So, this, uh, is a case of, uh, ACL tear day one.

43:47

This is the complete tear

43:48

of the ACL here in the Corona plane.

43:51

Uh, this is day one.

43:53

Here's the complete tear

43:54

of the ACL in the Corona oblique plane in

43:57

this area right here.

43:59

So this is day one. Now, six months later, we can see,

44:03

still see the complete air of the ACL right here.

44:08

Uh, but, uh, notice that the, the direction of the ligament,

44:12

uh, the, the distal stump is not horizontalized.

44:15

It's almost, it's like, uh, a parallel

44:18

to the bluma line, right?

44:20

So this is the area of the complete air. Here.

44:23

We can see a kind of, uh,

44:24

empty notch sign here in this region right here.

44:27

So this is with six months.

44:29

This is with six months with the complete tear of the ACL.

44:33

But look, see that the, the fibers, the, the gal fibers

44:38

of the ligament, they keep the direction, uh, right?

44:43

Okay, so here is the s plane also showing this tear of the,

44:47

uh, ACL six months later.

44:49

And now I'm gonna show you one year later, look,

44:52

one year later, one year later,

44:54

we can't see the lesion anymore.

44:56

We can't see it's, it's healed.

44:59

I'm not saying that's the, the function

45:01

of the ligament is preserved, right?

45:04

Probably that's why the patient, uh, is, uh,

45:09

it's, uh, return to the, to the clinic to do a new exam.

45:14

Uh, it's healing, but sometimes it heals.

45:17

But the functionality is lost.

45:19

And ev, but, so even if it's healed,

45:22

the orthopedic surgeon has to,

45:27

to, to operate this ligament, to reconstruct the ligament,

45:30

because the functions lost even cases with, uh,

45:35

uh, ACL that, uh, was healed.

45:39

So this is one year later, we can't see the lesion anymore,

45:43

uh, on the Sagal plane.

45:44

On the Corona plane. We can also, uh, look,

45:47

we can't see the lesion anymore.

45:49

We can't see the lesion anymore.

45:51

Uh, look, the Corona oblique plane,

45:53

we can see the ligament right here.

45:56

We can't see the gap, uh, as we could see at day one.

46:00

And, uh, and at six months.

46:03

So this was a ligament that healed.

46:06

One year later, probably it was, uh, inter sheath,

46:10

uh, ACL tear.

46:13

And, uh, the, uh, the sheath was preserved.

46:17

So the syn novo fluid, it not embedded the, the,

46:22

the stumps of the ligament.

46:23

So in the ligament, it could, uh, without this, uh,

46:27

interference of this synovial fluid,

46:30

the ligament could heal.

46:32

But again, sometimes it can heal,

46:35

but it can, it, it, it's not stable, it not works well,

46:40

and the patient has to have the ligament reconstructed.

46:43

Anyway, so this was one year later.

46:46

Okay, so we talked about the direct findings

46:49

and to, uh, finish up, uh, this lecture,

46:53

I'm gonna talk a little bit about the indirect findings.

46:55

Sometimes we are in doubt if the patient has a cell tear

46:59

and these indirect findings, they can help us.

47:02

Um, one indirect finding is the anterior draw, right,

47:06

the distance between the posterior cortex

47:08

of the lateral femoral condyle

47:10

and the lateral tibial plateau.

47:12

It should be, uh, it should measure until five millimeters.

47:16

More than that, this is a sign off anterior draw.

47:20

This case here, for example, a case of ACell tear, the,

47:24

the measure was 11 millimeters.

47:26

So this was a case with anterior draw of the tibia.

47:31

Uh, another finding is the hyperangulation

47:36

of the posterior cruciate ligament.

47:38

Uh, generally speaking, when the,

47:41

when the tibia it's, is in, in its normal position,

47:46

it's not anterior anterior, the

47:50

posterior cruciate ligament, uh, it axis it goes, uh,

47:55

it points to the femur.

47:57

Uh, in case of anterior, uh, anterior draw of the tibial,

48:00

uh, it causes, uh, PCL hyperangulation

48:04

or a booking of the PCL.

48:07

And this axis of the PCL, it points posterior

48:11

to the femur, right?

48:12

So the distal line, the distal PCL line passes posterior

48:16

to the post posterior distal femoral cortex in cases

48:20

of, uh, a c tear.

48:22

And this is, uh, secondary side of ACell tear, basically

48:26

because of the anterior driver of the tibia.

48:29

Uh, it's a specific sign, but it's not sensitive.

48:33

Uh, but it's something that can help you, uh, here as exam.

48:37

Here's an example of a normal, uh, PCL angle,

48:41

and here, uh, hyperangulation of the PCL in a case

48:45

of a chronic base, uh, a chronic, uh, a c tear right here.

48:51

So, uh, another sign,

48:52

or another indirect find

48:53

that can help us is the ratification, uh,

48:57

of the lateral collateral ligament, right?

49:00

Uh, the, with the anterior tibial draw

49:06

the, uh, distal insertion

49:09

of the lateral collateral ligament, it goes forward

49:13

and it, the, the normal insertion, it,

49:16

it has a different plane,

49:18

but the femoral insertion of the ac,

49:20

the lateral collateral ligament, it has a different plane

49:24

for a coronal plane from, for, uh, the,

49:26

the distal insertion, right?

49:28

When the patient has a ACL tear,

49:31

and it, uh, the patient has, uh, anterior driver

49:34

of the tibia, uh, the ACL, it, the, the femoral,

49:38

the proximal insertion,

49:39

and the distal insertion, they tend

49:41

to be at the same corona plane,

49:44

at the same plane at the Corona plane.

49:46

So with the anterior tibial translation,

49:48

the a l becomes parallel to the coronal plane.

49:52

So we can see the ACL in one

49:55

or two slices, for example.

49:57

Here's a normal, uh, a normal patient with a normal ACL.

50:02

We is, we have to see the

50:05

lateral collateral ligament in 1, 2, 3, 4 cuts

50:10

to see all the, uh, lateral collateral ligament.

50:13

Now look, this patient with, uh, complete of the ACL,

50:17

we can see the, uh, the lateral collateral ligament in just

50:22

one, uh, one slice at the coronal plane.

50:25

Because the tibia, uh, is, uh, anterior

50:30

to the normal position,

50:31

there is an anterior driver of the tibia.

50:34

So, uh, another sign that help us to identify,

50:39

uh, instability of the tibia, anterior draw

50:42

of the tibia is the uncovered lateral meniscus sign.

50:46

What happens, normally speaking, the posterior horn

50:49

of the medial meniscus, it should be, uh,

50:54

in this area right here, the posterior portion

50:56

of the lateral, uh, the posterior, uh, cartilage

51:00

of the lateral tibial plateau.

51:01

Okay? So a vertical line from the posterior margin

51:05

of the lateral tibial plateau cannot touch the lateral

51:08

meniscus posterior horn.

51:10

If it touches the posterior horn of the lateral meniscus,

51:14

it is a sign of anterior draw of the femur,

51:18

and it's a sign of an ACL insufficiency, right?

51:22

So that's what happens.

51:23

So now this line, it touches the posterior horn

51:26

of the lateral meniscus in one paper, uh,

51:31

they showed that 18% in patients with a C tear

51:35

and 0% in the control group without patient tear.

51:38

So again, it is specific, but it's not sensitive.

51:42

Uh, here's an example of a com complete tear of the ACL.

51:48

And here we can see this posterior line

51:51

of the tibial plateau touching the posterior horn

51:54

of the lateral meniscus.

51:55

And by the way, there, by the way,

51:56

there is also a vertical tear

51:58

of the lateral meniscus right here.

52:01

That's a zip lesion or a rip lesion.

52:04

Uh, again, a lot of things

52:05

to talk about the companion lesions

52:08

that can happen with ACell tear.

52:11

But just keep in mind now, in this moment,

52:14

this uncovered lateral meniscus sign.

52:17

And here's another case, a complete tear of the ACL.

52:20

Uh, when we trace this line posterior to the

52:23

lateral tibial plateau, we can see that this line,

52:26

it touches, crosses the posterior horn

52:30

of the lateral meniscus.

52:31

So again, this is a sign of ACL insufficiency.

52:36

This is a sign of A ACL tear,

52:38

and here, uh, PD with fat suppression PD

52:41

with fat suppression showing the, the, this sign,

52:45

uh, in this case.

52:47

And we are finishing,

52:49

I'm finishing the lecture in my lecture in the

52:52

next, uh, five minutes.

52:54

But I still want to talk about some, uh,

52:57

important topics right here at the end of the, this lecture.

53:01

And one of these topics,

53:03

it's about the tibial intracon bone fusion.

53:07

Most of the time, the lesion, or the rupture,

53:10

or the tear of the a c, it occurs at the ligament itself,

53:14

but sometimes, especially in young patients,

53:17

it can occur at the tibial footprint, not at the,

53:22

uh, at the interface between the ligament and the, the bone,

53:26

but in the bone itself.

53:28

Okay? So this is a bone of vision

53:31

that we can see in younger patients.

53:33

So in it's more common in children

53:35

and adolescents, uh, it can cause a fast

53:39

and intense hemo, heor, osis,

53:42

and inflammatory changes in comparison

53:45

with the other types of ACL tear.

53:47

So here is a case with a huge, uh,

53:52

bone fusion CL bone fusion, uh, caused from, uh,

53:58

from the ACL instead of the, the, the, the tear of the ACL,

54:03

the, like, let's say that the weak point was the bone.

54:07

Uh, so it caused a bone marrow a,

54:11

a bone fusion in this region here.

54:13

So, uh, when you see, when you see, uh, bone marrow fusion,

54:17

a bone fusion of the tibia at the ACL footprint,

54:22

in case like that, uh, you should, um, uh, you should look

54:27

for, uh, you should know how are

54:31

the meniscal root ligaments,

54:33

because sometimes the meniscal root ligaments,

54:35

they are also in this, uh, volt bone fragment, right?

54:40

For here, for example, this is anterior horn

54:43

of the middle meniscus, uh, maybe half

54:48

or part of the anterior horn

54:49

or of the anterior root ligament is in this, uh,

54:53

bone fusion right here.

54:55

But look at the, uh, at the anterior horn

55:00

or the anterior, uh, root ligament of the lateral meniscus.

55:04

It goes straight to the bone fusion right here.

55:09

So the anterior root ligament

55:11

of the lateral meniscus is also in this bone fusion.

55:15

We can see that here in the coronal plane.

55:18

Here is the, oh, look, this is the arterial root ligament

55:22

of the lateral meniscus.

55:23

And this, uh, inserts is straight on the bone

55:28

of fusion, uh, caused by, uh, traction of, uh,

55:33

ACL in this patient right here.

55:35

And you should report that in your,

55:38

uh, in your exam.

55:40

You should put that in your report.

55:42

Uh, uh, what structures are in, uh,

55:46

are inserted in this bone of vision.

55:50

Okay? And to finish up, I'd like to talk a little bit about,

55:54

uh, the second, second fracture.

55:56

The second fracture, uh, it's a fracture

56:00

that occurs at the interlateral portion of the

56:04

lateral tibial plateau.

56:06

Uh, in this region right here, uh, this is the area

56:10

of insertion of the interlateral ligament

56:12

and the posterior fibers of the iliotibial band,

56:16

of the iliotibial tract.

56:17

Okay? And this is a marker of the ACell tear.

56:21

Most of the time when you see a second, uh, fracture,

56:24

this patient also has, uh, ACL tear.

56:27

Sometimes you see that on the x-ray,

56:29

and you can, uh, infer

56:33

that this patient has a high, uh, probability

56:37

to have a tear of the anterior cruciate ligament.

56:40

So this bone fragment, it measures until 10 millimeters.

56:44

It can be difficult to see on the MRI

56:47

because sometimes there is no bone marrow edema, and the,

56:51

and the bone is too thin, the cortex here, uh,

56:54

sometimes it's just the cortex that goes away,

56:58

and it's too thin to identify this bone marrow edema.

57:02

And it's not pathognomonic of an ACL tear,

57:05

but it's very common in this condition, very common

57:08

with the ACL tear.

57:10

So here is an example of this patient has, uh, ACL tear.

57:14

And here this is the I Tial band right here,

57:17

and here in the posterior portion of the iliotibial band.

57:21

And here at the area of the insertion of the,

57:25

an lateral ligament, we can see this bone

57:29

of fusion right here.

57:31

This is the second, the second fracture. Okay?

57:35

So keep that in mind.

57:37

That's another secondary finding

57:39

or indirect finding of ACell tear.

57:42

So, uh, uh, game over. No, it's not game over.

57:45

There's a lot of things to talk about the ACell tear, a lot

57:48

of like, uh, uh, companion, uh, lesions that can happen,

57:54

uh, with the ACell tear.

57:55

But my time is over, and I think that's okay.

57:59

That's, uh, that was great for today.

58:02

Um, um, from tba, Brazil,

58:07

I'd like to thank you, uh, modality, MI online

58:10

for the opportunity to be here.

58:12

Thank you, Dr. Rasnick.

58:14

Because I, uh, I am, I, I'm be one of the staffs, one

58:18

of the, the, the teacher of his team on the next, uh,

58:23

course that will, uh, that will be some,

58:28

if I'm not mistaken, in October this year here

58:30

on the modality.

58:32

Um, and that's it.

58:34

Thank you for the opportunity,

58:35

and I hope you all, uh, got something, uh,

58:40

useful for this lecture today.

58:42

Uh, thank you so much, Dr. Aguiar.

58:44

Um, and at this time, uh, we will open the floor

58:47

to questions if our audience members have any,

58:50

and you may submit your questions

58:52

through the q and a feature.

58:54

It looks like we have a couple in there already. Dr.

58:56

Aguiar, if you're able to pull up your q and a box.

59:00

Okay, I hear with my q and a box,

59:02

and the first question that I, that I, uh, uh,

59:06

I see here is from Moray Solomon.

59:09

And he, he is asking, uh, is there a difference

59:14

between rampal lesion and meniscal capsular separation?

59:17

Okay, this is a good question.

59:19

Rampal lesion, uh, it has,

59:21

there is some controversy in this topic,

59:24

but generally speaking, ramp lesion, it's a lesion

59:27

that occur at the periphery of the posterior horn,

59:30

of the middle meniscus in case

59:33

of ACL tears, okay?

59:36

And the meniscal capsular separation in this region is

59:42

one of the types of the ramp lesion, okay?

59:45

In case of ACell tears, okay?

59:47

But if you see, uh, a meniscal separation, then there is

59:52

no ACell tear.

59:53

Don't call that ramp lesion, just call

59:55

that a meniscal capsule separation, okay?

59:59

Don't call that ramp lesion. Ramp lesion.

60:01

You just call if you see a ACell tear, uh,

60:06

together in this patient.

60:09

Um, let's see. Second question.

60:11

He came, uh, send me this one.

60:14

ACell tear in between the synovial sheath seems

60:19

like inter synovial tear, not intra synovial tear.

60:24

ACL lives outside the synovial normally.

60:26

Thanks for the talk. Okay, good observation.

60:29

Uh, uh, that's was like the, the,

60:34

the terms that, that I've got in the literature,

60:38

but, uh, it's something that to, to think about.

60:42

Uh, and thanks for the tip. Thanks for the tip.

60:45

Uh, about, like your thoughts about this.

60:48

Um, tu

60:52

what about chronic tears?

60:54

Is it possible to say if it was partial

60:58

or complete tear without the previous MRI exam?

61:00

How do you describe when we can't see the gap,

61:03

but you know, that it has been torn previously?

61:08

Do you always say that this, you always say

61:10

that the surgeon should test clinically in that cases?

61:14

Thanks and congratulations for the lecture. Thank you, atu.

61:17

Um, um, about the, the chronic tears, uh,

61:21

we don't have like the edema to help us.

61:23

Sometimes it's difficult to see if there's some continuity,

61:27

uh, of the fibers or not.

61:30

And I, I, I, I, I, I tend to use like,

61:34

the direction of the ligament if the ligament is straight,

61:38

or if I see some fibers going straight, like parallel

61:41

to the esad line.

61:42

Uh, generally speaking, I, I, I say that, that

61:45

that is a partial tear.

61:47

If I don't have the, the previous exam, it's hard sometimes

61:50

to define if it was a complete error with a,

61:54

with some healing associated.

61:57

Uh, but, uh, in cases when I'm in doubt,

62:02

I put this doubt in my report,

62:05

and I always like, uh, uh, I, I always, uh, put in my report

62:10

that this finding should be, uh, correlated like clinically

62:15

to test insufficiency of the ligament,

62:17

because that's a good way in, uh, for you that,

62:22

'cause sometimes you can't be sure about what's happening,

62:25

but it's also good for the orthopedic surgeons

62:28

because sometimes, uh, you give them some leeway,

62:31

you give them some space to say, okay, I tested

62:35

and it was insufficient when I test it, so I will, uh,

62:40

operate this ligament.

62:42

Because sometimes when you don't see,

62:43

or don't you when you don't say nothing, uh, it can be hard

62:48

to the orthopedic surgeon to explain, let's say

62:51

for the insurance plan plan that he, uh, he wants

62:56

to perform a surgery in this patient.

62:58

So when you put that on, on your report, you also help them.

63:02

Uh, most of the cases, uh, uh,

63:07

Hamesh Zoo Z car.

63:10

So sorry about my, my, my, my, my French here, uh,

63:14

because people from all the, the, the world, so it's hard

63:19

to get the name of everybody, right?

63:21

Right. But, uh, let's say no.

63:26

Okay. Can you elaborate about pre-op

63:29

and post-op care of a C tear?

63:32

Uh, it's, uh, for this lecture, it's too much.

63:35

I think I should like, uh, uh, make a,

63:38

or present like a lecture about the post op ACL,

63:42

because, uh, this is, uh, a, it's a broad topic

63:46

to talk right now.

63:47

Sorry, Ramesh, uh, uh, Hamed, uh,

63:52

talked about the a c graft injury.

63:54

Yeah, that's a, that's a topic about the, uh, uh,

63:58

postoperative ACL, uh, tear, for example.

64:02

And you should see, let's say, uh, for how long, uh,

64:06

this patient, uh, is operated

64:09

and there are like the,

64:12

some specific patterns depending on what's the age

64:15

of the graft of the ACL, what graft was used.

64:19

So again, uh, for this, uh, session today, uh, it's, uh,

64:24

I need to make another, like another lecture to, to be more,

64:28

to talk more about this topic, really.

64:32

Uh, good day jam, uh, jam Christian, good day.

64:37

Uh, it's, is it necessary

64:38

to always include a separate ACL plane on

64:41

the MRI for the knee?

64:43

Um, it, I think that the Corona bl plane is

64:47

a very good plane to evaluate ACL, right?

64:50

Uh, generally speaking now in the, uh, the facility

64:54

that I work, we don't use any specific plane

64:58

for the ACL, but I miss it.

65:00

If I could, I would like come back

65:02

and return with the ACL, like the oblique plane,

65:07

Corona BL plane in our routine.

65:10

But we don't use, and hopefully we start doing like 3D MRI

65:15

and we can reconstruct in any plane that we want.

65:18

But if you have time, uh, if you have you schedule, uh,

65:23

allow, allow is, allows it, I recommend use,

65:28

uh, specific o especially the, the oblique Corona,

65:32

the Corona oblique plane for the ACL.

65:36

Uh, Dr.

65:41

Ebra, uh, asked about the partial ACL tears.

65:45

I talked a little bit about the partial a c tears,

65:49

but, uh, what i, I can tell you about that.

65:52

It's like, uh, if you can't put which bundle is to

65:57

in your report, that's great.

65:59

If you cannot, uh,

66:00

if you're not sure about which bond store, just put

66:03

that there is a partial ACell tear.

66:06

And, uh, what, uh, what it would be.

66:09

This, the decisive for the patient is the, is the clinical

66:14

exam by orthopedic surgeon to decide if the patient, uh,

66:19

goes to surgery or not.

66:22

Uh, uh, anonymous attendee.

66:26

What do you think about stress resonance imaging

66:28

for evaluation of chronic partial anterior

66:30

crucial ligament injuries?

66:32

I don't have, uh, experience with, uh,

66:38

with stress resonance imaging,

66:40

but I think that's a good idea.

66:42

Right. Uh, it's like, uh, I've seen some works,

66:45

some papers about that.

66:47

They, uh, they have like great results, uh,

66:51

but I don't have experience to tell you,

66:53

but I think it's, it's, it's worth a try.

66:57

Uh, how do you describe if, uh, agata,

67:00

how do you describe if you can't see the gap,

67:03

but ACL is swollen

67:05

and the fibers does not follow the bloomin cell line?

67:08

It's, it, this is like the cloud-like pattern that I,

67:11

that I've talked, uh, in the lecture.

67:14

Right. I would describe that there is, uh,

67:16

the ligament is irregular heterogeneous

67:19

that we cannot see the continuation of the fibers.

67:23

Uh, it can be,

67:25

or I will, I would suggest, uh, a complete tear

67:29

of the ligament and

67:34

hamre ham.

67:36

Uh, sorry about my pronation again.

67:38

Uh, thanks so much for answering my question.

67:40

Please make a lecture about the private post care.

67:46

Okay. Uh, I, I, I'm gonna talk with the,

67:49

the organizers about that.

67:51

Uh, okay.

67:54

I, I think we got all of our questions, Dr.

67:56

Aguiar, I think, I think we're good to go.

67:58

So thank you so much for your lecture today

68:00

and taking the time to answer questions,

68:02

and we would definitely love to have you back

68:04

for another lecture for sure.

68:06

Okay. Uh, it was my pleasure to be here with you today,

68:09

and I hope that everything, everybody, uh, I helped, uh,

68:13

everybody to, to get a little bit better at the evaluation

68:18

of the MRI of the ACell Tears,

68:21

and have a great day, everybody.

68:24

Absolutely. And thank you to everyone

68:26

for participating in our noon conference.

68:29

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68:30

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68:33

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68:36

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68:39

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68:42

M Mahesh will deliver a lecture entitled Imaging Pregnant

68:45

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68:47

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68:49

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68:53

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