0:01

This is a 49-year-old man.

0:02

He's a weightlifter.

0:04

Congratulations at age 49.

0:06

He's very muscular, and you should notice that right away.

0:09

No fatty infiltration in large

0:11

muscles, but he's not 20 years old.

0:15

And what's the difference?

0:17

Well, the difference is obvious, but

0:20

20-year-olds have acute dislocations.

0:23

The incidence of acute collision type unidirectional

0:29

dislocation diminishes with age, even in weightlifters.

0:32

Even in people that are active.

0:34

People that are active that are 40, 50, 60 years old tend

0:38

to have remote bouts of macro unidirectional instability,

0:43

or not, but bouts of micro-instability of varying degrees.

0:49

So the odds of them having, at age 50 or

0:51

60, multi-directional micro-instability

0:54

compared to the 20-year-old are much higher.

0:58

And that's important because there are two basic

1:01

spectrums, or two basic continuums of instability.

1:05

At one end of the spectrum is the major

1:07

traumatic dislocation first-time event.

1:11

And at the other end, there's either no

1:14

antecedent trauma or remote antecedent trauma.

1:17

And that's what we have here.

1:18

Now how do you know whether you've had remote

1:21

antecedent trauma when you were 24 years old?

1:24

Well certainly, history might help.

1:26

Or you can simply look at the architecture.

1:29

Let's look at the architecture on this T1-weighted image.

1:31

T1-weighted image.

1:32

Nice and round.

1:34

When we get to the back of the shoulder

1:36

though, look at the top of the humeral head.

1:39

It looks a little bit serrated.

1:42

A little bit flattened.

1:44

And that's, this suggests to us that, actually

1:48

this is anterior, this suggests to us that the

1:50

patient has had supra-inferior instability.

1:55

In other words, that the humeral head has

1:58

at some point been bounded up and down.

2:01

Yes, this is anterior because there is the coracoid.

2:03

So you can see I made a quick

2:04

mistake there, even I make mistakes.

2:07

We also notice the glenoid remodeling.

2:11

Anteroinferiorly, the glenoid is serrated, it's irregular,

2:15

there are some spurs, there's a small spur off the humerus.

2:18

Another sign in a weightlifter who's active,

2:22

who's a strong guy, of micro-instability.

2:27

So now let's look at the sequela of micro

2:29

instability, which will include what I call

2:32

partial labral tears, less profound labral tears.

2:38

And what do they consist of?

2:39

Glad lesions, guard lesions, fissures, cysts, slap lesions.

2:43

Let's have a look.

2:45

Let's take all three water-weighted images.

2:48

I'm gonna put up the sagittal water-weighted image on

2:51

the far right, the coronal water-weighted image in the

2:54

middle, and the axial water-weighted image on the left.

2:58

Let's start out with the axial, because

2:59

that's what you're most comfortable with.

3:01

And we go all the way to the back, and

3:03

we see a little bit of signal here.

3:04

Is that fluid or is that a tear?

3:07

No, it's outside the labrum.

3:08

It's fluid.

3:08

All right.

3:09

Let's keep going, shall we?

3:10

Let's go forward on our coronal.

3:13

We see recesses between individual structures, like the

3:18

biceps and the rotator cuff and caracohumeral ligament.

3:22

So we've got this laminar pattern, but no slap lesions.

3:26

As we come down, things look a little bit busy.

3:29

I think it's time to go to the axial projection.

3:32

Let's scroll our way down.

3:34

There's our biceps up high.

3:36

We go down, we see labrum.

3:39

And any fissures and separations of the labrum

3:41

from the glenoid up high should go away.

3:44

Do they?

3:44

No, they don't.

3:46

In fact, one in the substance of

3:48

the labrum becomes more prominent.

3:51

There's swelling of the hyaline cartilage at its base.

3:55

Not surprising, because we already

3:57

know there's glenohumeral arthropathy.

3:59

And our lesion has busted out anteriorly.

4:03

As a small anterior paralabral cyst.

4:07

Is that all?

4:08

No, that's not all.

4:10

We've got a small little erosion in the glenoid.

4:15

take a look at the posterior labrum.

4:17

Is it normal?

4:18

No, it's not normal.

4:20

It's not detached, but it's got evidence of

4:22

an old, healed, scarred, partial rim tear.

4:26

I'm gonna make it bigger, so you can see it.

4:29

Right there.

4:30

How do you know it's not hyaline cartilage?

4:32

Because hyaline cartilage doesn't go all the way out.

4:36

Let's take a look at the capsule.

4:38

Capsule's right there.

4:39

It comes around.

4:41

It's got a little bit of synovial thickening in it.

4:43

It's redundant.

4:45

So there's a little bit of capsular plasticity.

4:48

There's an old chronic labral tear.

4:50

There's a little bit of arthrosis in the inferior quadrant.

4:54

We clearly have a tear in the labrum.

4:57

Perhaps not through and through.

4:59

Part of it's healed.

5:00

Part of it's cystic.

5:01

Part of it's busting out anteriorly.

5:03

It's creating.

5:05

Inflammation in multiple directions of the shoulder.

5:08

The rotator cuff is intact and this is a weightlifter

5:12

with multi-directional micro-instability as

5:16

opposed to the single collision event athlete.

5:20

Let's have a look at another one, shall we?