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Okay, this is a 21-year-old pitcher who

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complains of decreased range of motion.

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Perhaps he's guarding.

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And we've got a series of coronal images before you.

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A T1 fat-weighted image on the left.

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In the center of the ring, T2 spin

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echo image without fat suppression.

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In the blue corner on the right-hand side, we've

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got a proton density fat suppression image.

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We're on instability.

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Could be micro, could be macro

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instability, could be combinations thereof.

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So, many of you have locked onto this signal

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in the suprapostralateral humeral head.

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And thinking instability, you might think Hill-Sachs.

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But you'd be wrong.

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Hill-Sachs is going to be located in the 12 o'clock

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position or within 2 to 5 millimeters thereof.

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Can they be lateral?

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Yes, they can.

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But are they etched?

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Are they notched?

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Do they have a sharp edge to them?

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Well, only if they're hatchets, you

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know, with recurrent dislocation.

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They'll look something like this.

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But they won't look like erosions.

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And typically, in overhead athletes, especially

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pitchers and javelin throwers and volleyball players,

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from continued abduction and external rotation,

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the humerus is going to swing out, and this area

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is going to come in contact with the acromion.

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When that happens, you develop a trough.

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Underneath that trough, you often develop

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pseudocysts or intraosseous ganglia.

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These are signs of impingement.

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They are not signs of a Hill-Sachs lesion.

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So if you automatically go down the road of a

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Hill-Sachs lesion, you're going to end up over

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reading Bankart and macro instability lesions.

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have labral ligamentous disease and not have a Hill-Sachs.

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And one of those times is when you have an

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overhead athlete, you have big-time deceleration,

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uh, injuries with high-velocity activities.

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And unfortunately, these patients, all these

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overhead athletes have signs of impingement with

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troughs and pits that simulate Hill-Sachs lesions.

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And I've seen people operated for these lesions as

2:28

labral pathology when no labral pathology exists.

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But in this case, labral pathology does exist.

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Let's look at all three images.

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The T1-weighted image.

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The architecture of the glenoid is normal.

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The architecture of the inferior glenohumeral ligament?

2:47

Ill-defined.

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Gray.

2:49

Swollen.

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Let's look at the T2.

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The ligament proper.

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In other words, here is the axillary band of the IGHL.

2:58

It's intact.

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Let's look at it anteriorly.

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It's still intact.

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A little bit redundant, folded on itself.

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Let's go to the back.

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It's a little droopy, as it often is in a throwing athlete.

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And here's how neat it becomes.

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Stretched, but it's intact.

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Now let's go to the uber-sensitive PD image.

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And the labral ligamentous relationship

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to the glenoid is disrupted.

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The labrum. Remember, you should never have

3:32

signal going all the way across the labrum,

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medialized towards the center of the patient.

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That is a sign of a tear.

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So the labral ligamentous complex has pulled off, yanked

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off, detached from the inferior aspect of the glenoid.

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And it's through and through.

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And it involves the periosteum.

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It has to.

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Because there's periosteum right here.

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So right at the junction of the periosteum

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and the labrum, it has come out.

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So now let's look at the axial projection.

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We have two axial projections.

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Let's put them up in conjunction with one coronal.

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There's one, there's the second.

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And now let's scroll.

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I'm gonna blow them up a little bit, so

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they're a little easier for you to see.

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The one on the right is a gradient echo, the one

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in the center is a proton density fat suppression.

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And, I am sure that many of you are looking at this

4:31

thinking, "Oh, that's got to be a Hill-Sachs lesion."

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And on the PD, it's kind of ill-defined, so it takes the

4:36

T1-weighted image to define the character of this lesion.

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It takes the coronal to define the

4:42

position of this lesion in an impinger.

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Let's start up high, everything looks fine.

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The labrum is smaller up high.

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As we go down, the labrum should get bigger and blacker.

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And it does.

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It gets bigger and blacker than the superior labrum.

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It gets bigger and blacker than the posterior labrum.

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Yes, there are some small linear fissures inside,

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none of which are giving rise to paralabral cysts.

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None of which are giving rise to focal areas of swelling.

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Yes, there's a little bit of swelling around the labrum.

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So these are probably small wear-and-tear type fissures

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that have occurred in the labrum in this throwing athlete.

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There's also a small little rim dit

5:27

at the base of the labrum right there.

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Not uncommon, very shallow in throwing athletes.

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Now when they're really deep, they may

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give rise to something known as a GLAD

5:38

lesion, a Glen labral articular disruption.

5:40

But that's not the problem.

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The problem is down low.

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So look at this potential pitfall.

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You're scrolling in the an inferior

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aspect of a labrum, and it looks.

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Hunky-dory.

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Nothing is separated.

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Nothing is detached.

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And the reason is, you're not in the region

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where the labral ligamentous injury occurred.

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That's down here, in the axillary space.

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So this is a tricky case.

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It's tricky because The injury in this throwing athlete

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is axillary rather than anterior or anteroaxillary.

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It's tricky because he's an impinger, and the impingement

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related trough is simulating a Hill-Sachs lesion.

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This is very dangerous.

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When you call this a Hill-Sachs lesion, it's

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very embarrassing when it turns out not to be.

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Especially if there's no problem

6:35

in the anteroinferior labrum.

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Now over time, these non-displaced lesions,

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if the patient isn't properly rested, will

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become flat out, very detached, bankrupt.

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So they'll separate.

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In other words, let's put up the coronal again.

6:50

This will eventually separate.

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If you rest the patient, this can granulate

6:55

in, it can scar in, it absolutely can heal.

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Now as the degree of displacement increases,

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The anteroinferior glenoid becomes bare and

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if the patient continues to dislocate, what'll

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happen is this area will just gradually erode

7:13

down and become flatter and flatter and flatter.

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So you'll lose some glenoid bone stock.

7:18

Another reason to recognize that

7:21

the patient has instability.

7:24

And with repeated dislocation, you'll start

7:26

to see hyaline cartilage flaps and these

7:29

flaps may detach from the glenoid fossa.

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So there's a progression.

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If this goes unchecked, the progression is, glenoid,

7:36

sorry, the labrum floats away, the extent of the

7:39

labral tear progresses from the bottom to the

7:42

top, the patient starts to wear away the bone,

7:46

the patient starts to wear away the cartilage, and

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the cartilage separates from the underlying bone.

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So, tricky case, impinger, pitcher,

7:56

infraro axillary, Bankart type lesion.

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Let's move on to another one, shall we?