0:01

Let's take a collision case in a 21-year-old

0:03

and look at a series of axial images.

0:09

A T2 spin echo with fat suppression on the right,

0:12

a PD with fat suppression on the left, a little more

0:15

water weighted, a little better edge detail with

0:18

regard to the ligamentous relationship to the labrum.

0:23

But we're going to be interested in this case

0:26

with regard to labroskeletal relationships.

0:31

Labroskeletal relationships right there, labrum skeleton.

0:34

ligamentous labral relationships and

0:38

even periosteal bone relationships.

0:41

So there's a lot going on here in the axial projection.

0:45

Let's start up high.

0:45

There's a tremendous amount of swelling.

0:48

And as in The Wizard of Oz, I'll ask you to pay no attention

0:51

to the edema behind the curtain in front of the scapula.

0:55

Yes, there is a large effusion.

0:57

The patient has had a violent injury.

0:59

And yes, there is a Hill Sachs lesion.

1:02

Whose diameter we would assess by drawing a

1:06

best fit circle around the humerus and seeing

1:09

what percent of our humerus is involved.

1:13

And probably, once again, about 15%.

1:15

Not a lot of depression.

1:17

And we would scroll up and down to find the biggest

1:19

area of involvement and the biggest area of depression.

1:22

We're not going to do that right now.

1:23

We're going to focus on the labra.

1:26

Our 21 year old football player is certainly

1:29

going in the gym and doing this, right?

1:31

He's bench pressing, he's pushing, maybe he's a

1:34

lineman and he's pushing and what has he done?

1:36

He's created a tiny little partial rim tear in the back.

1:41

A so-called reverse Perthes lesion or Kim's lesion.

1:46

A small little separation, sliver-like or pouch

1:50

like, between the labrum and the underlying glenoid.

1:53

Where do we see that?

1:54

In virtually every young athletic boy that

1:58

participates in these kinds of activities.

2:02

But that's not why we're here.

2:03

We're here to see that portions of

2:06

the anterior glenoid are devoid.

2:08

They're laid bare.

2:10

They're laid waste by the absence of this fragmented labrum.

2:15

Let's keep going down, shall we?

2:18

Yes, we still see a labrum, but

2:20

no, it is not properly attached.

2:23

It is separated by this.

2:25

Bright, white, traumatic fissure.

2:28

And does that fissure go all the way through?

2:30

You bet it does, right there.

2:32

Let's make it even bigger, so you can see a little better.

2:35

Goes through right there.

2:37

Now I'm going to zoom out a little bit.

2:40

So this patient has A Bankart type lesion.

2:45

Now, to make matters worse, the lesion is

2:48

entering right at the base of the Hyaline

2:52

cartilage and even involves the Hyaline cartilage.

2:55

Had it gone on to the glenoid and involved the labrum

3:01

and the Hyaline cartilage, which I'm drawing here

3:03

in blue, had it gone in and done this, involved the

3:08

hyaline cartilage and partially gone into the labrum.

3:11

We would've called it a GLAD lesion, a

3:14

glenoid, a Glen labral articular disruption.

3:18

Or, had it simply stayed right here, at the base of the

3:23

labrum, or maybe just clipped a little bit of the labrum

3:25

at the base, we would have called it a guard lesion.

3:27

A glenoid articular rim divot.

3:31

But, unfortunately, neither of those is the case.

3:36

What we have is a labrum that we've

3:38

already established is torn, right there.

3:42

And right there, and not so much right

3:45

there, but a very deep tear right there.

3:48

But it goes through and through, so it's a true Bankart.

3:52

It has involved the base of the Hyaline

3:54

cartilage, so it's got some complexity to it.

3:59

And it also has torn the capsule.

4:03

So the capsule is torn, this balled up, irregular, ill

4:07

defined, fluffy gray signal relative to the labrum.

4:11

And it's on multiple cuts.

4:13

It's swollen right here.

4:16

So there is a labrocapsular injury.

4:21

Has there been a periosteal injury?

4:23

You bet there has.

4:25

The periosteum is markedly elevated right there.

4:28

We'll blow it up on the right-hand side on the T2.

4:31

And right there.

4:32

Let's take a look at the capsule on

4:34

the T2 where it's a little clearer.

4:37

It looks like the ring of fire.

4:39

It's irregular.

4:39

It's complex.

4:41

It's not linear like it should be.

4:44

It's torn.

4:46

So we have a capsulolabral injury, a labroskeletal

4:50

injury, a periosteal skeletal injury, right there,

4:56

and we also have a labrocartilaginous injury.

5:01

So we might call this a quadruple lesion.

5:04

If there are only three of them, a triple lesion.

5:07

If there are only two of them, a double lesion.

5:10

And at some point later, we'll talk about the

5:12

Perthes lesion, which is known as a single lesion.

5:17

Let's take the coronal projection, just for giggles, to

5:20

make sure that we don't have an axillary abnormality.

5:25

And do we?

5:26

Well, not on the humeral side.

5:28

But we certainly do on the

5:30

glenoid side, make it even bigger.

5:35

Look at what's happened to our labroskeletal junction.

5:39

It is separated with a medialized cleft all

5:43

the way out the inside, separating the inferior

5:47

labrum from the bone, along with the glenoid.

5:51

The capsule that's attached to it, the

5:53

IGHL, is attached to this piece of labrum.

5:56

What's all this?

5:58

Fragmented capsule, fragmented periosteum, dissecting blood.

6:03

So not only is this an anterior lesion with triple or

6:08

quadruple characteristics, it's an inferior extension

6:12

of that labral tear that started at 3 o'clock, Went all

6:16

the way to six o'clock, and we're not done just yet.

6:21

Let's look at our superior labrum.

6:23

We know it's a weightlifter, so just to be

6:26

complete, even though this isn't part of the macro

6:29

instability story, we know the patient has micro

6:32

instability with a reverse Perthes or Kim's lesion.

6:35

And do they have little SLAP

6:37

lesions from doing military presses?

6:39

They sure do, because you should never

6:41

have clefts going in this direction.

6:44

We'll From inframedial to supralateral and the

6:47

superior labrum in the back of the shoulder.

6:50

Sulci are allowed in the front, but not in the back.

6:53

So the patient has a chronic SLAP

6:55

lesion to make matters more complex.

6:58

Are we done yet?

7:00

No, we're not.

7:02

Let's have a look at the sagittal projection.

7:06

So, my sagittal projection, I like

7:08

to look at the glenoid bone stock.

7:10

And it's pretty good.

7:11

We can see a small divot at the

7:14

hyaline bony interface right here.

7:16

But it's pretty smooth, and pretty round, and if

7:19

we draw a best fit circle, we do have a circle.

7:22

So we really don't have any bony, glenoid bone loss.

7:26

And this is probably the best way on MRI to assess it.

7:30

Now we do have quite a bit of activity here

7:33

anteriorly, because we've got blood, we've got

7:35

periosteum, and we've got capsule in the front.

7:39

So that concludes our discussion of this

7:43

patient that has a Hill-Sachs lesion we see in

7:46

the back, A complex Bankart lesion with not

7:49

one, not two, not three, but four components.

7:53

Labro bony, labro ligamentous, labro periosteal,

7:59

and labro hyaline involvement, making it a

8:04

quadruple lesion or Bankart variation in

8:08

the anterior and anteroaxillary region.