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So this is a 42-year-old woman with a

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history of prior labral repair, and the

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patient has pain, pain with weight-bearing,

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and I'm sure her pain is quite substantive.

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So let's begin with our coronal orthogonal

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unilateral T1 spin echo image without contrast.

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And the first thing you should notice is the,

0:26

is the irregularity of the free acetabular edge.

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In concert with that, you should notice

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that the acetabulum doesn't appear to

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be long enough or broad enough to cover

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the drop-off of the head-neck junction.

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In other words, there's not enough tissue

0:47

out laterally to hold the head properly.

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And that is probably one reason why the

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patient developed an acetabular injury

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that got repaired in the first place.

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The acetabular roof, which has

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quite a bit of horizontality to it,

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is a little bit less horizontal than usual.

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It's not vertical, but it

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is a little bit oblique.

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The T1-weighted image also shows a

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somewhat stuttering gray appearance to

1:19

the labrum with some small erosions in

1:22

the acetabular roof, not unexpected.

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Now let's move over to our unilateral

1:29

fat suppression, water-weighted sequence.

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And we have a large hole, or gap, between the

1:38

acetabulum and the capsule, which is formed

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by the iliofemoral ligament, which is a

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thick condensation of the capsule that wraps

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around the side and the front of the hip.

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Here's the rest of this capsule,

1:53

or iliofemoral ligament, which has a

1:57

triangular type origin, more proximally.

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And then it comes down and around, and in

2:03

part, merges with the transverse ligament.

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So let's scroll the sagittal projection,

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in this patient who has a labral repair.

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And on prior vignettes, you've learned

2:13

that a contiguous black triangle should

2:16

droop or hang down from the acetabulum.

2:19

And we don't have that, do we?

2:22

We've got a defect between this

2:25

triangle and the acetabulum.

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So our labral repair has failed.

2:32

We've got a labral tear.

2:35

We don't see that as well in the coronal

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projection, but what we do see is a large gap

2:40

between this tissue and this tissue,

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which represents acetabulum, labrum,

2:48

detached piece of labrum, capsule,

2:53

hole in the capsule, stripping of the capsule.

2:57

In contrast to a prior case you've seen in a

3:00

vignette called large paralabral cyst in the

3:04

right hip of a 38-year-old aerobics instructor

3:08

or personal trainer who had a paralabral

3:11

cyst as opposed to a capsular rupture.

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This is a capsular rupture.

3:18

Now, let me take you to the coronal

3:20

projection after we've given contrast.

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We put contrast into the joint.

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Here's your sagittal.

3:29

Here is a coronal T1.

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and look at how much more difficult it is.

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On the coronal T1 with contrast,

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let me see if I can grab another

3:42

coronal sequence with it.

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Well, we'll probably have to

3:47

go with this one right here.

3:50

Let's look at our coronal T1.

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And yes, we do see a labral tear,

3:56

but it's a little harder to appreciate

3:59

that this is actually a capsular rupture,

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as opposed to just some cyst that is communicating

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or filling with intra-articular contrast.

4:10

In other words, the diagnosis of

4:12

capsular separation, in my opinion,

4:15

is much more easily made without the

4:18

contrast being introduced into the joint.

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Of course, if you were able to watch

4:23

it extravasate through, it'd be easy.

4:25

Now, the labral tear is seen right

4:29

here as a somewhat complex area of

4:32

signal alteration, superolaterally.

4:35

But one could easily confuse this as a

4:38

paralabral cyst coming this way, as opposed

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to a capsular rupture coming this way,

4:44

if you did not have that pre-contrast image.

4:48

So this case illustrates two important things.

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One, that there's a capsular rupture.

4:54

And two, that the diagnosis of the

4:57

capsular rupture is more easily made on

5:00

the non-arthrographic image than it is

5:03

made on the post-arthrographic MR image,

5:06

which is unnecessary and time-consuming.

5:10

And indeed, the patient has both

5:11

a labral retear and a capsular rupture.

5:15

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