0:01

Let's move on and talk, uh,

0:02

briefly about some bone abnormalities

0:04

that are kind, kind of interesting.

0:07

Tomorrow. I'm gonna talk about elbow instability,

0:11

and you're gonna learn about the elbow lock.

0:14

The elbow lock is the relationship between the

0:17

humorous and the ul.

0:19

They are locked. The tr

0:21

and trochlea notch owing to their shape are locked in place.

0:26

So when you develop stress in the baseball pitch,

0:29

or over time, cortical thickening may occur in the two

0:34

components of the elbow lock.

0:36

The humerus has shown here and in the ulnar,

0:40

but the radius, which is not part of that elbow lock,

0:44

typically does not demonstrate this particular finding.

0:48

I call this feminization of the humerus, alright?

0:52

Because it begins to look like a femur.

0:54

Look how thick, how thick in fact, that, uh, cortex is.

0:59

The first time I I saw this was on a film panel

1:03

and they showed me a case and being well-trained.

1:06

I looked at it, it looked even worse than this.

1:09

And I made the incorrect diagnosis.

1:11

I made it with confidence by the way of Paget's disease.

1:15

Turned out it was a, a rodeo rider. And I said, well, wait.

1:18

They, they, they're on the, the ball about 15 seconds.

1:21

How can they possibly develop this stress?

1:24

But they practice on these mechanical balls.

1:27

And so you get this in tennis players, in rodeo,

1:32

uh, people were, are in rodeos.

1:34

And you certainly get this in the baseball pitcher

1:37

and the ulna may participate in it.

1:40

A number of stress fractures occur in the throwing shoulder.

1:43

The classic one is in the scapula.

1:45

Here's the typical example.

1:47

It's linear, often obliquely oriented as shown in this case.

1:52

Here's another one with some bone proliferation.

1:55

At the site of the fracture,

1:59

there is a particular fatigue fracture

2:02

that involves the humerus in baseball, pitchers

2:05

and other, uh, athletes involved in throwing sports.

2:09

This is what it typically looks like.

2:11

It is associated with a fracture line, cortical thickening,

2:15

perote reaction,

2:17

and sometimes extensive marrow edema

2:21

stimulating the appearance of infection or tumor.

2:26

And then the other condition that may

2:28

or may not be associated with a, uh, stress fracture,

2:32

fatigue fracture is the condition we call post-traumatic

2:37

osteolysis of the clavicle.

2:39

Now, this particular condition can occur following a single

2:43

injury or repetitive stress.

2:46

And in some reports,

2:48

the classic finding is marrow edema dominating in the

2:51

clavicle, but occasionally involving the adjacent acromion.

2:56

In some of those cases, if you look closely,

2:58

You'll see a linear region in the clavicle as shown here

3:04

representing a stress fracture.

3:05

But something I've learned,

3:07

whenever you have marrow edema, you unmask trabecula.

3:11

And it's very easy to put an arrow on any prominent

3:15

trabecula and call it a stress fracture.

3:18

So these are overdiagnosed as well.

3:21

You don't always have a stress fracture

3:23

with post-traumatic osteolysis of the clavicle.