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I'd like to tackle with you a high-performance

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athlete, a ballet dancer who uses her hips

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in extreme internal and external rotation.

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But before I do, let's talk about the

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potential causes of intra-articular

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pathology, especially in a ballet dancer.

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As we'll see, the labrum will be our focus,

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but we would be searching for things like loose

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bodies, signs of femoroacetabular impingement,

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capsular abnormalities, oft-overlooked

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abnormalities of the ligamentum teres.

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Here's our labrum off to the side.

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And abnormalities of the chondral surface.

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There's an important list of

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extra-articular abnormalities.

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We're going to cover it at a later date.

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And there's an important list of mimickers,

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such as sports hernias, and athletic

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pubalgia, and osteitis pubis, that we'll

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cover in usually male performance athletes.

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But in this category, we already have a thought

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in our mind of what the pathology should be.

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In a ballet dancer with hip pain.

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And it should be either labral pathology

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or abnormalities of the ligamentum teres.

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We can easily exclude abnormalities

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of the ligamentum teres by

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looking at the ligamentum teres.

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There it is, and we'll learn

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that it has both two heads.

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An ischial head and a pubic head.

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That is a story for another day.

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But here is our labrum,

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attached to the calcified layer of cartilage

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and the rim of the acetabulum, transitioning

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into the adjacent hyaline cartilage.

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It goes around the hip, deepening the

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cup, and securing the synovium within the

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joint, along with the hip joint capsule.

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As we scroll through the garden variety,

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easy-to-perform, T1-weighted image.

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Most of you will note the gray signal intensity

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between the small, triangulated labrum.

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And yes, they are triangular in younger

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people, but change shape as age advances.

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And that gray signal could either

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be some hyaline cartilage, a

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tear, or a sulcus or variation.

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That's a difficult distinction to make.

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But at first glance, on this

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water-weighted image, water signal

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intensity doesn't fill in this space.

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So your initial thought would most

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likely be, this is not a tear.

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As we continue to scroll the T1-weighted image,

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which is my preferred image to look at the

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outline of the skeletal anatomy, and I use

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it a lot like an X-ray, I see a few things.

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First I see this funny-looking notch, which

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is a fusion point for the normal triradiate

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cartilage that evolves to form the acetabulum.

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And that's normal and okay.

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A story for an anatomic day.

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We also have a small ridge along

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the lateral aspect of the femur.

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You know that the femur should be a ball.

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It's a ball-and-socket joint.

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Well, our ball has a little cliff on it.

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That doesn't belong there.

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Now for somebody like me, that's not as

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active as a ballet dancer, maybe as active as

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a belly dancer, that wouldn't be a problem.40 00:01:49,255 --> 00:01:51,625 As we scroll through the garden variety,

1:51

easy-to-perform, T1-weighted image.

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Most of you will note the gray signal intensity

1:59

between the small, triangulated labrum.

2:02

And yes, they are triangular in younger

2:05

people, but change shape as age advances.

2:09

And that gray signal could either

2:11

be some hyaline cartilage, a

2:14

tear, or a sulcus or variation.

2:17

That's a difficult distinction to make.

2:20

But at first glance, on this

2:22

water-weighted image, water signal

2:24

intensity doesn't fill in this space.

2:27

So your initial thought would most

2:29

likely be, this is not a tear.

2:32

As we continue to scroll the T1-weighted image,

2:35

which is my preferred image to look at the

2:38

outline of the skeletal anatomy, and I use

2:41

it a lot like an X-ray, I see a few things.

2:45

First I see this funny-looking notch, which

2:48

is a fusion point for the normal triradiate

2:52

cartilage that evolves to form the acetabulum.

2:56

And that's normal and okay.

2:58

A story for an anatomic day.

3:02

We also have a small ridge along

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the lateral aspect of the femur.

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You know that the femur should be a ball.

3:14

It's a ball-and-socket joint.

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Well, our ball has a little cliff on it.

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That doesn't belong there.

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Now for somebody like me, that's not as

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active as a ballet dancer, maybe as active as

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a belly dancer, that wouldn't be a problem.

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But for somebody that is abducting and

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doing splits in the air and on the ground,

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that is a problem, and your suspicion

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should automatically be heightened that

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something is likely wrong with the labrum.

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So let's pick out an axial projection.

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We have not yet given any contrast.

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This is an axial T2-weighted image.

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It is used to assess the capsule,

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which is this darker tissue around the

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outside that helps secure the joint.

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It is used to look at the insertion of

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the ligamentum teres on the fovea capitis

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in this area known as the pulvinar.

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It does a reasonable job of showing you

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the small, very small, triangular-shaped

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dark labrum, but here's the problem.

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If the labrum is injured and it has a little

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bit of blood, blood is dark, labrum is dark.

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If the labrum is injured and it has a little

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bit of scar, scar is dark, the labrum is dark.

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Therefore, the T2 axial image, while

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having many strengths, is not an

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optimal way to see a labral tear.

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Now, most labral tears can be

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followed superior to anterior.

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That is where they usually occur

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in this group of individuals.

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And, in fact, in most athletes in the United

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States, the labral tears are in the front.

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However, in most athletes in Japan,

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the labral tears are in the back.

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Because many of their sports

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activities are related to squatting.

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So if you extrapolate a little further and

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you think about an American baseball catcher,

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their labral problems will be in the back.

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But most of the other athletes have

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their labral problems in the front.

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Here is an axial, less T2-weighted image.

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It's a T2 without fat suppression.

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And still, we see the labrum as

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a small, triangulated structure.

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Without a clear-cut abnormality and are

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able to follow it from superior to inferior.

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There is our ligamentum teres.

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We're focusing on the two most likely

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areas to be affected in a ballet dancer.

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We're using our brain and some common sense.

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Let's go to the sagittal projection.

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This sagittal projection is

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incredibly useful in the hip.

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In some parts of the body, for instance, the

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wrist, it's the least favored nation projection.

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But for labrum, it is a critical projection.

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For 20 percent of the time, the labral tear

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will only show up in the sagittal projection.

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Now this case illustrates not only a labral

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tear in a high-performance athlete, but an

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incredibly subtle, difficult example of such,

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to urge you into the subsequent series of

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educational programs that we have before you.

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That little tiny cleft that you're seeing

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in the anterior superior labrum with

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a little bit of swelling underneath.

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That's a labral tear.

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And the sagittal projection was

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the only projection to depict it.

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Let's go down the line a little bit.

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We have actually injected and done

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an MR arthrogram on this joint.

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We've got the non-arthrographic image coronally.

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That's suppressed.

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Let's go a little bit further and

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pull up the arthrographic image now.

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I'm going to blow it up so you

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can see it a little bit better.

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And I think many of you would

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be wondering about this signal.

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Is it a cleft, a normal

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variant cleft, or is it a tear?

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Now one sign you can use that unfortunately

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is not present here, if it, if it goes three

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quarters or more depth, and this is right on the

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border, then you should be suspicious of a tear.

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Most clefts deepen in the anterior inferior

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aspect of the acetabulo femoral complex.

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We're not in the anterior inferior aspect.

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We're up high.

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So if this were a cleft, it

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should get deeper as you go down.

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It shouldn't be this

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conspicuous in a young person.

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Almost 75 percent depth.

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So between that and this funny ridge that

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we've already identified on the femur,

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Your suspicion is still heightened.

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We said that sometimes the sagittal

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projection is the only projection

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that shows certain labral tears.

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And here it is.

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The patient has had a heavily water

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weighted, fat-suppressed image so

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that the bone is absolutely black.

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The water that has been placed

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in the joint is absolutely white.

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The hyaline cartilage, here.

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The capsule, a thin, dark slit, here.

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And hyaline cartilage of the femur here.

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Should add up to about 3 millimeters.

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I tell you this because the third.

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Diagnosis, which is unlikely, but.

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Possible, would be an injury to the.

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Hyaline cartilage in a ballet dancer.

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The hyaline cartilage throughout the.

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Hip should add up to about 3 millimeters.

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In a healthy, young, 18-year-old.

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Girl, which this is, and it does.

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So you might say, you put contrast.

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In the joint. Where is that contrast?

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It's not in the upper part of the joint.

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It's lagging through this thing we call.

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Gravity in the lower part of the joint.

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So it isn't really enhancing.

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Up high like we would like.

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A little bit of exercise.

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Would take care of that.

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But nevertheless, we shouldn't.

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Have this irregular, jagged.

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Signal going through and through.

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To the superficial portion of the labrum.

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And out the anterior margin of the labrum.

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This is anterior, this is posterior, and.

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It is those two slices only that show the.

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Character of this small labral tear in a.

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High-performance athlete that is flexing.

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Abducting, adducting, and externally rotating.

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So-called plié, in ballet dancing that is.

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Producing extreme symptoms. As a result of.

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Her activity and this funny looking little.

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Ridge along the outer aspect of what should.

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Be a smooth cup, but is no longer smooth.

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If that scares you, it should, because.

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We want you to dive deeply into the.

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Labrum with us to make sure that you're.

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Able to make this diagnosis and not over.

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Call ones that are normal variations.

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Let's move on, shall we?