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Now we're here with a middle-

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aged to younger patient who's got

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bilateral hip pain and grinding.

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And we've started off with some bilateral

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imaging, and we said there are two

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good reasons to do bilateral imaging.

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One, just to get a view of the

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morphology and compare the two sides

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of the hip, the right versus the left.

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To look for other areas of potential

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pathology that may masquerade as hip pain.

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And unfortunately, you may also be tasked

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with seeing every single other structure

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on the image of which there are 30, 40, 50

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different structures, including prostate,

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colon, iliopsoas muscle, spine, etc.

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But there's probably a third reason to get

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bilateral imaging that we haven't discussed.

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And that is to see the orientation and angles

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that were properly acquired

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for your other sequences.

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Now in prior vignettes, I showed you how to

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obtain a radial sequence off of a sagittal.

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This is an orthogonal coronal.

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And now I'm going to show you how to

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acquire an oblique axial off the coronal.

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So let's look at the right hip first.

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So I'm going to try and put the hip in

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the plane of section, and now let's look at

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the right hip, and you can see the axial,

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which is a thin section, gradient echo,

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3D slab, with 1 mm cuts, with 50 percent

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overlap, is angled along this long axis of

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the hip. It is not a straight orthogonal.

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This is really an ideal way, not just

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to look at the labrum, but also to look

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at the lack of sphericity or presence

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of sphericity of the head-neck junction.

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Now what do I mean by sphericity?

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I mean that the head is tapering

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into a gradual, thin, delicate neck.

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And we'll talk more about this in the left hip.

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But we want to see that transition.

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For patients that have very broad

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necks, or bumps in their necks,

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are more prone to pathology.

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But let's focus on the angle right now.

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We've got a long axis image that is

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ideally suited for acquisition of an

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alpha angle, but it's also ideally

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suited for assessment of the labrum.

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So let's scroll up and down.

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We're down, we're up.

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Let's go down and pay very careful attention to

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the labrum. We've put no contrast in this joint.

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And the joint has a tiny bit of fluid,

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but I would describe it as relatively dry.

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Let's keep going, shall we?

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Keep looking, keep looking.

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And wow, we have just stumbled, mumbled,

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and crumbled into a crumbling labrum.

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And where are we?

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Just above the labral, sorry,

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just above the femoral equator.

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We're right here.

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So in the anterosuperior, not in the most

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superior, but in the anterosuperior aspect

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of the hip, we've got ourselves a labral tear.

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And no amount of contrast is going

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to improve upon that diagnosis.

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Let's keep looking, shall we?

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The labral tear is still there.

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It's still present.

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And now it's gone.

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Perhaps there's just a little slit of

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it left in the anteroinferior quadrant.

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We're not all the way inferior yet.

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Actually, I take it back.

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It's still present.

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There it is, right there.

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It goes all the way into the

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anteroinferior quadrant.

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I apologize.

3:44

So it goes from anterosuperior,

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fades away for a bit, I've lost

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it, and now it's come back again.

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As a very well-defined slit in the right hip.

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It's a pretty interesting labral tear.

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There are also, although not shown here,

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innumerable, but very tiny, paralabral

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pseudocysts from this tear that were visible on

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a PD SPIR bilateral study as part of this exam.

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Let's go on to the left hip.

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The same angulation is used.

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Let's start up really high.

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And we actually see some of

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these cysts on the left side.

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So we know immediately there

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has to be a labral tear.

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And let's continue down now.

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Here is the triangulated labrum.

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There's our paralabral cyst, which

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is dissected from below and come up.

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How do we know that?

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So, of course, we're going to run

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smack dab into that labral tear.

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But let's keep going, shall we?

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And as we work our way down, there is a

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well-defined, linear, sharp discrepancy

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between the labrum and the underlying

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acetabulum, where most tears occur.

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It's right there.

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You might say, would I call that

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a labral tear without contrast?

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You bet you would.

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You bet you should, especially

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with those paralabral cysts.

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But it's not just on one, one millimeter cut.

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It's still present.

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Let's keep going.

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It's barely visible, and,

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but it's still present.

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There it is.

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It's a partial thickness tear

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as we get a little bit lower.

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So it doesn't quite have the top to bottom

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excursion of the tear on the right side.

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But it is definitely and unequivocally a tear.

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No sulcus.

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No sulcus is going to go all the way

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through the labrum and out the front.

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No sulcus is going to have that very

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linear knife-like pattern with that

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obliquity from lateral to medial or

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from posterolateral to anteromedial.

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A sulcus is going to be shallow.

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It'll have a little curvilinear top to it.

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And it'll never be associated

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with paralabral cyst formation.

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Now, if you wanted to perform an

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alpha angle on this patient, there

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is a very subtle bump right here.

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You might take a line, you would bisect

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the femur, your second angle would go right

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at the top of this bump transition to the

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femoral head, and this would be your alpha

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angle, which, by the way, is greater than

6:30

55 or 60 degrees, and it is abnormal.

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But I'm showing it.

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Primarily, for the proper angulation

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for axial obliques in labral assessment

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acquired off a direct coronal orthogonal

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to bring forth the diagnosis of bilateral

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labral tears with paralabral cysts,

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which accounts for the patient's clinical

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syndrome of bilateral hip pain and grinding.

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Thanks.