0:00

This next 69-year-old patient is

0:03

going to give you a brain freeze.

0:05

There're so many findings present.

0:07

He fell.

0:08

He dislocated.

0:10

Let's scroll our T1 fat-weighted image on the left, our

0:15

water-weighted fat suppression image in the middle,

0:18

and our clean-up T2-weighted spin echo image on the right.

0:23

There are quite a few findings that strike you immediately.

0:28

For instance, you can't find a biceps or a biceps anchor.

0:31

It's gone.

0:32

Almost all the structures of the rotator

0:34

cuff, maybe some infraspinatus fibers present.

0:37

But other than that, infraspinatus gone.

0:40

Supraspinatus gone.

0:42

Subscapularis, some mid to upper fibers

0:45

okay, lower fibers, they're gone.

0:48

We've already said the biceps is gone.

0:50

So a multitude of findings.

0:52

The AC joint has osteolysis.

0:55

And probably has had a partial

0:57

resection or Mumford procedure.

1:00

So, lots of things happening here, including

1:03

impingement-related changes, troughs

1:06

and pitting of the greater tuberosity.

1:09

But this patient dislocated.

1:11

And here is the area of the Hill-Sachs,

1:13

slightly off the 12 o'clock position.

1:16

Uh, let's bring down, for a minute,

1:18

we'll take away our T1-weighted image.

1:20

Let's bring down our axial for a moment.

1:23

I'm gonna blow it up just to make it a little bit bigger.

1:26

So you can see some of the abnormalities.

1:28

For instance, these fibers of the subscapularis are off.

1:32

You can't find a biceps.

1:34

The posterior capsule is torn and injured.

1:37

A very nice view of the hyaline

1:39

cartilage on the humeral side.

1:41

A small little ding right there.

1:44

And then some smooth hyaline cartilage.

1:46

That's the good news on the glenoid side.

1:49

Let's go up to the Hill-Sachs lesion.

1:51

It's not that big.

1:52

It's pretty small.

1:53

It's certainly not depressed.

1:55

And typically defects that affect the humeral head

1:58

that are 20 percent of the circumference or less at

2:02

their level, they're usually clinically significant.

2:06

When they get about 25%, they can be significant, but

2:10

if you have a good capsule, or you've got remplissage

2:14

or capsularophy, they're usually not problematic.

2:17

Um, just sheer circumference measurements, and we're gonna

2:21

get into more complex measurements in later vignettes.

2:24

But if you've got, say, 40 percent of the

2:26

circumference involved, that usually is an ominous

2:30

sign, prognostically, for recurrent dislocation.

2:34

So let's get off our, let's get off our Hill-Sachs

2:37

horse for a moment, and go back to our coronal images.

2:42

I'm not gonna spend a lot of time, on the

2:45

sagittal image in this case, because all the

2:47

interesting pathology is in the axillary region.

2:51

So let's go to the back, posteriorly in the coronal

2:54

projection, where we can see the takeoff of the

2:57

infra-posterior axillary band of the glenohumeral

3:00

ligament, and the humeral attachment is not normal.

3:04

So, there is at least a partial tear of these structures.

3:08

You can see it on the T2 in the form of, of grayish signal.

3:12

There's a nice black ligament.

3:14

And then there's a gray, scarred portion of the ligament.

3:18

Now, it's helpful to get these infra-axillary tears

3:21

acutely, because when they scar down, they can

3:24

simulate ligaments, and you can easily miss them.

3:26

In a haggle discussion, I mentioned to you that

3:31

when you have very nasty infra-axillary, uh,

3:35

ligament injuries, you can get these big pouches.

3:38

These pouches, especially if they're

3:40

distended, can prolapse down.

3:42

This one is and forms this pseudomass down here.

3:47

If it's distended, it can even encroach on the neurovascular

3:50

bundle and contribute to brachial plexus syndrome.

3:54

So now as we move forward a little bit, we see to better

3:58

advantage the attachment of the anterior band of the IGHL.

4:02

Yeah, there's a little high-ish.

4:03

Signal in it, but it's attached, but the middle of

4:08

the stretched IGHL is torn, right there in the center.

4:14

So, at least the antero-axillary portion of

4:18

the IGHL, which normally doesn't make this big,

4:21

giant, pouch-like loop, is bisected right here.

4:24

There's the bisection right there, to

4:26

give you a little bit of eye candy.

4:30

Now, if that wasn't enough, oh, there's, there's more.

4:33

There's so much more.

4:36

Let's ignore all this swelling and bursal fluid and

4:41

extravasation of fluid out of the joint capsule,

4:44

which is busted and tracking into the axillary space,

4:48

tracking into the soft tissues, and let's go to the

4:52

glenoid side of the infra-axillary glenohumeral ligament.

4:58

Let's go right to the middle.

4:59

That should be attached to this structure right here.

5:04

In fact, let's use the T1 as a drawing tool map.

5:09

So there's your glenoid in orange.

5:13

And let's give, give ourselves a labrum.

5:15

Let's make our, well, we should make our

5:16

labrum blue because that's cartilage.

5:18

Let's make our, our labrum yellow.

5:21

And we can't see our labrum on T1 because

5:23

it's so edematous, but we do see it over here.

5:26

So let's pretend we do see it.

5:28

And let's make it right there, and then coming

5:31

off there, we should have a nice ligamentous

5:35

structure, the labral-ligamentous complex.

5:38

Which we'll use as a nice light purple.

5:41

So you should have something that looks like this.

5:44

Then it should come down, it should

5:46

fold over on itself nice and tightly.

5:48

And then insert on the humeral neck.

5:51

That's what the anatomy should look like.

5:54

Oh, but that's not, that's not occurring, is it?

5:59

for a minute before we scroll.

6:01

That is over here.

6:05

See, that structure should be over here.

6:08

So the glenoid side of the infra-axillary

6:13

glenohumeral ligament is detached from the labrum.

6:16

That is a true glenohumeral avulsion of

6:20

the glenohumeral ligament, or gaggle.

6:22

Now, more commonly, this comes off

6:25

with that, sort of a pseudo-gaggle.

6:27

So you can have an isolated detachment of the

6:30

axillary labrum with the ligament attached to it.

6:35

Rarely, this'll come off, and that will come off this.

6:40

That's the least common of the three.

6:42

The most common, though, is the

6:44

labrum coming off with the ligament.

6:47

In other words, the yellow coming off with the purple.

6:50

That's not happening here.

6:51

The yellow has stayed on.

6:53

The purple has come off.

6:55

To make matters worse, we have transected

6:59

the ligament in the middle of, of its course.

7:03

And we've also got some posterior injury.

7:06

If we scroll back posteriorly, as we showed you originally.

7:10

The posterior band of the inferior

7:13

glenohumeral ligament was torn, too.

7:14

So we had a component of a reverse haggle or a raggle.

7:18

So this is a threefer, right?

7:22

We've got, we've got a raggle, reverse haggle.

7:25

We've got an axillary cut or a tear

7:28

of the axillary portion of the IGHL.

7:31

And we've got a gaggle, all three, compounded

7:35

by rotator cuff tears out the yin-yang.

7:40

Everywhere, almost every structure

7:42

involved, compounded by plastic deformation.

7:46

Now let's take our color away and scroll.

7:48

Plastic deformation of this big structure

7:52

now that is distended and stretched, allowing

7:55

capsular fluid to extravasate down and around

7:59

into the axillary space creating this big pouch.

8:03

If you did an arthrogram and distended this shoulder.

8:06

You might see the pouch distend with some scar or

8:09

you might spill your contrast right through this hole

8:13

into the axillary space and that wouldn't be good.

8:17

By the way, when you have an explosion, an implosion,

8:21

I mean massive injuries with lots of swelling and

8:24

you're looking at your scan and saying who's who, who's

8:28

where, who's the batsman, who's on first and second,

8:32

that's the time to call up your T2 weighted image.

8:35

Because that's going to clean things up for

8:37

you a little bit, and it certainly does.

8:40

There is the glenoid side of the

8:42

ligament, which should be here.

8:44

There's the ligament.

8:45

There's the defect.

8:47

That should be attached to that.

8:49

There's the pouch.

8:51

And there anteriorly is the attachment of the

8:53

humeral side of the inferior glenohumeral ligament.

8:58

Three for one.

8:59

Raggle, gaggle, axillary ligamentous tear.