0:00

Let's move on now

0:01

and, uh, we're gonna move on to the, uh, acetabular side.

0:07

And here we deal with pincer impingement.

0:09

I'll show you where that term comes from,

0:12

and such entities as acetabular protrusion

0:15

and acetabular retroversion.

0:18

Now, as recently described in the literature,

0:21

acetabular protrusion occurs when the femoral headline,

0:25

this line labeled h crosses the ileal issue line,

0:30

which is this line.

0:32

Now, in my view, I don't like that particular term.

0:35

I think that's more a better term as femoral head intrusion

0:39

because the size

0:42

and status of the cartilage will influence when in fact

0:46

that femoral headline crosses the ILE issue line.

0:51

But still, this is the modern definition

0:53

of ace, the protrusion.

0:56

There is another term that has been recently introduced,

0:59

which is Cox Profunda.

1:02

Here, the acetabular fosil line, which is this line, right,

1:07

touches or crosses the ileal is issue line,

1:11

which is this line in my view,

1:13

this is acetabular protrusion,

1:15

but the proper term for this now is Cox Profunda.

1:20

Now, many years ago,

1:21

we looked at the hip morphology in women compared to men,

1:25

and I can tell you

1:27

that Cox Profunda can occur normally in women.

1:31

All right? It is uncommon to see this particular

1:35

appearance in men, however.

1:39

So here is a normal picture radiograph on your left.

1:42

Here's an example of Cox Profunda. Okay?

1:46

You can see that, and here on a transverse image is showing

1:50

you how thin the acetabular floor might be.

1:55

Now, I look for this on the transverse images.

1:59

You can see it in other planes as well with Mr Imaging,

2:03

but I don't have a measurement for you to say

2:06

what is pathologically thin,

2:08

but this is paper thin, something that you may see.

2:12

So if we compare here, the normal

2:16

to Cox Profunda, you can appreciate that

2:19

with certain positions of the hip, the femoral neck

2:23

may contact and,

2:25

and injure the acetabular labrum anteriorly

2:29

and drive the femoral head posteriorly leading

2:33

to cartilage damage involving the posterior

2:36

aspect of the hip joint.

2:38

Here's an example of that. All right.

2:41

Uh, you can appreciate here the thin acetabular floor,

2:46

the narrowing, not pretty images,

2:47

but you can see the narrowing of the cartilage in the back.

2:51

Typical Cox of profunda with

2:55

acetabular cited primary femoral acetabular

2:58

Impingement.

3:00

And to complete our story on the acetabular side,

3:03

there is acetabular retroversion.

3:06

In normal well positioned images of the hip,

3:09

you will find the anterior acetabular rim medial

3:13

to the posterior acetabular rim.

3:16

But in some persons, the anterior acetabular rim superiorly

3:21

is seen lateral to the posterior acetabular rim.

3:25

This is called acetabular retroversion

3:28

or acetabular superior retroversion.

3:32

Here's the normal anterior acetabular rim,

3:35

posterior acetabular rim.

3:37

Here with the yellow arrow is the an acetabular rim crossing

3:41

over the posterior acetabular rim.

3:44

All right, acetabular retroversion,

3:47

and some people have said, when you look at it carefully,

3:50

you can draw a figure of eight sign.

3:54

So here again with acetabular retroversion compared

3:58

to acetabular aversion, you can see

4:01

how the labrum might be injured.

4:05

This looks like a pincer effect, hence

4:07

that term has been utilized.

4:10

There are other forms of acetabular morphologic changes

4:15

that can lead to pincher type impingement.

4:18

For example, a posterior acetabular wall shown here

4:23

that extends more lateral than the center

4:26

of the femoral head.

4:28

That is a prominent posterior acetabular wall.

4:31

So two types of impingement can impingement, developmental,

4:36

perhaps related to delayed physio closure,

4:39

resulting in a bump that will lead to tearing

4:43

or separation of the, uh, superior

4:47

or anterosuperior labrum with often cartilage abnormalities.

4:52

That might include delamination

4:55

and pincer type impingement

4:57

where the femoral neck will crush the, uh, labrum

5:02

and drive the femoral head posteriorly.

5:04

The cartilage abnormalities posteriorly.

5:08

There is another form of, uh, impingement

5:11

that has been described recently.

5:14

Anin iliac spine is the culprit here,

5:18

typically following mal united fractures with enlargement

5:22

of the anterior iliac, uh, anterior in IAC spine.

5:25

There may be a form of impingement that may occur

5:30

where the femoral neck contacts the, uh, proximal femur

5:34

during flexion of the hip,

5:36

and people have described a bump in these cases known

5:40

as distal cam, uh, impingement

5:44

occurring a little bit more distally.

5:46

The alpha angle would look normal in such a case.

5:50

And then finally, also femorals tabular impingement.

5:53

Intrinsic abnormalities like degenerative thickening

5:57

of the ligament of terries can also produce hip impingement.