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We're here with a gorgeous magnified picture

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of the labrum, the acetabulum, and the capsule.

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And let's use our drawing tool to

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help you analyze the individual

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components of labral injuries.

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Let's start out in this area that's

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a slightly different shade of gray.

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And let me pick a color here.

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I think I'll choose blue.

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And this is all hyaline cartilage.

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The hyaline cartilage is going to have a

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transition zone into fibrocartilage.

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And one of the most common types of

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tears is a separation right about here,

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where you see it's a little bit lighter,

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between the labrum and the hyaline area.

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This is an area of disruption that is

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often vertically oriented or inclined.

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Now the labrum may then tilt upward,

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like this, or just completely

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displace, or it may just sit there.

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Depending upon how big and

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how deep this injury is.

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This is one of the most common

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types of acute traumatic labral

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injuries in younger individuals.

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Sometimes when that is very severe, and that

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usually occurs with a twist, with an impaction.

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So, in other words, if you fall on your

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knee with a twist, that'll result

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in this type of tear in a young person.

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You may also flip the labrum up and

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strip away this capsule here, so the

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capsule may also begin to detach from

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the underlying bone and periosteum.

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That is a very serious abnormality that requires

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surgical intervention, usually by arthroscopy.

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Now let me reinitiate my...let me

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get my eraser out here for a moment.

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And let's look at some other

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types of labral injuries.

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I'm gonna draw for you a meniscus in the knee.

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And I'll use the color blue again.

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And I'll try and make it

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a little 3D-ish looking.

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Now when you have a meniscal injury in

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the knee that is vertically oriented,

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it can be vertical in the outer third,

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or it can be vertical and be in the inner

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third, but in a different orientation.

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The one in the inner third

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is known as a radial tear.

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And what that looks like in the knee,

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if you put a triangle right through

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this area, is something like this.

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And then, at the tip,

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it's all what I would call mushy.

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It's filled in with other stuff,

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so it's no longer a meniscus, and the

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meniscus is, as we say, truncated.

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So what happens in the labrum of the hip?

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Well, in the labrum of the hip,

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you can mush the tip of the labrum

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in any one of a number of ways.

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You can have a vertical injury,

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and then it just flips off and detaches.

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You can have a large, macerated,

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horizontal injury, and then the labrum

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eventually rips off and detaches.

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So the concept of radial injuries at the tip of

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the labrum is much more amorphous, even though

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strictly speaking, you'll read in the literature

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something analogous to what we see in the knee.

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That's a hard concept to really

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digest when you're looking at an MR.

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So for simplicity's sake, and I'm using the

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color green now, whenever I see the tip of

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the labrum just truncated off like someone

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came in with a knife and chopped it like some

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celery, I'm going to call that a radial tear.

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So there's a little bit of difference

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between it and the meniscus.

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A little more liberalism, although

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nobody likes to hear a liberal drone

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on for too long, as my son would say.

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And let's look at some other

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kinds of tears real quickly.

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Let's pick another color.

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A very common type of tear that we see

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in adults over a period of time

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is the straight vertical tear.

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Now we've already seen the meniscus

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of the knee, there are two types of

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vertically oriented or up and down tears.

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One radial to the arc of the meniscus,

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and one parallel to the arc of the meniscus.

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The common type of vertical tear

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in the labrum looks like this.

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Straight up and down, and I'd like to use

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a different color, let's go with orange.

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Straight up and down, like this.

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Very common to see these tears in

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people that are 50, 55, 60, 65 that are atraumatic.

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It is very uncommon at the top of

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the hip to have a sulcus there.

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So if you have a vertically oriented

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abnormality, especially if it's 50%

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depth or more, especially if it's not

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smooth and sulcated with a nice round top.

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It's probably, in fact, it's most likely

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a tear of chronic long standing duration.

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And these tears may progressively propagate as

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one gets older and eventually in degenerative

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hips or people with delayed developmental

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dysplasia, it may go through and through and

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now the labrum may detach and lop off and

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add to the symptoms that the patient has from

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other problems like DJD and chondromalacia.

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This is the most common type of tear that

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you're going to see in the adult, elderly

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individual without a specific episode of trauma.

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The last type of tear I'm going to talk about is

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one that parallels the long axis of the labrum.

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It is a little counterintuitive,

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and it runs this way.

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It runs parallel to the long axis of the labrum.

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Now you'll hear people talk about this

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type of tear as a longitudinal tear.

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That's a bit confusing

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because we have a longitudinal tear in the

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meniscus that really doesn't quite match it.

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And it usually occurs right

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in the center of the labrum.

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Now I don't have any objection to using

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the term longitudinal because it's

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running along the long axis of the labrum.

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You'll also hear people refer to these

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as longitudinal horizontal tears.

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You'll hear them referred

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to as horizontal tears.

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And frankly, I don't care which one you use,

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as long as you convey that the tear is running

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along the center of the long axis of the labrum

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and frequently these tears will then bend like

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Beckham and go right into the hyaline cartilage

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and you'll see a line into the hyaline space so

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that there is a hyaline to labral transition.

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And these are often very symptomatic tears.

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More on the types of labral tears

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and their implication in the next

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small vignette in this series.