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Now we have our most favored nation

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projection, the coronal projection with

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arthrographic contrast introduced into

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the joint to highlight the anatomy.

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Let's begin with the skeleton.

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The acetabulum, with its labrum, covers

0:15

the femoral head right at its drop-off.

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That proper coverage is one of the first things

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I look at in assessing the coronal projection.

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If the acetabulum is too far medially, we

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say that the coverage is insufficient or

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undercovered and the patient most likely has a

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variation of developmental dysplasia of the hip.

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There is a measurement for this

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that we'll discuss at a later date.

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I also look at the tapering of the

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femoral head-neck junction to make

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sure that it's symmetric and that there

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are no acquired or congenital bumps.

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When there is symmetric tapering,

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this is known as sphericity.

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But when the neck is too broad or

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bumpy, it's known as asphericity.

1:00

We have our transverse ligament, our

1:02

inferior recess bounded by the capsule.

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Here's a small synovial fold or foveal fold.

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The capsule is filled with some contrast,

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and the ligamentum teres comes up

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and inserts on the fovea capitis in the

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region of the femur with its two heads.

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We've got hyaline cartilage, the collapsed

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joint space, the fluid isn't distending

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it in this location, and more hyaline

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cartilage with a crease in the acetabulum,

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which is a normal developmental fusion

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site for the triradiate cartilage.

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Out laterally, on our water-weighted

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image, we see the capsule with virtually

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no fluid in a young person, interposed

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between the capsule and iliofemoral

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ligament and the underlying acetabulum.

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But fluid may creep into this space

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as one gets a little bit older, and the

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capsule naturally becomes more pliable

1:57

and strips a little bit away, and we may

2:00

see 2 to 4 millimeters of fluid interposed

2:03

between the labrum, the acetabulum, and

2:05

the capsule, and that's okay, as long

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as there are no other secondary signs.

2:12

We're able to depict the end of the capsule

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here and here, and draw a line between

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the two. For everything above that line is

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going to be intra-articular, as fractures.

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And everything below that line is

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going to be extra-articular, the intra-

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articular having a more grave prognosis.

2:34

So, this is a basic introduction

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to our coronal projection.

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The muscular insertions and origins

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you can get out of a textbook.

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Obviously, the greater trochanter.

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A very busy place where the gluteus

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medius, and more anteriorly, the minimus

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insert, along with the external rotators.

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But that will be a story for another day.

2:55

And finally, in conclusion,

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let's scroll our labrum.

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A beautiful, dark, thorn-like,

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homogeneous structure, tightly

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attached in the back to the acetabulum.

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Let's move to the front.

3:11

Sorry, that is the front.

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Tightly attached in the front to the acetabulum.

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Let's move to the back.

3:17

And there it is also,

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tightly attached to the acetabulum.

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In a young individual, I don't want

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to see any clefts that are more

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than 25 percent depth of the labrum.

3:29

And here I have one.

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In the anteromedial to superior aspect of

3:34

the acetabulum, I do have such a cleft.

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And that cleft, by the way, is a partial

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thickness labral tear in this young individual.

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So you've seen the good labrum, and

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you've seen the not-so-good labrum.

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And the rest of the anatomy is cold stone.

3:52

Thank you.