0:00

Let's turn now to contusion.

0:02

So contusions are different.

0:04

Uh, they are a direct blow to the muscle

0:07

and they heal relatively quickly.

0:09

Now, they may have a lot of blood associated with them.

0:13

So again, you may not have the history

0:15

and it can be hard without the history to tell

0:17

what it is you're looking at.

0:19

So in the main findings

0:21

that should suggest a contusion is bone edema, deep to it,

0:27

lot of soft tissue swelling, superficial to it,

0:30

and a lot of hemorrhage in the muscle.

0:32

But honestly, it can be difficult to tell them apart,

0:35

especially in a case like this, where the hematoma is, uh,

0:38

close to the tendon fibers.

0:40

So history becomes really, really important

0:44

to know whether there's been a direct blow,

0:46

'cause it's gonna change the prognosis here.

0:49

Now, many times, uh, we can recognize that the injury is,

0:54

um, is a contusion, uh, because of those ancillary findings.

0:59

I don't think bone edema is all that common.

1:02

This was a case, uh, given to me by Don, uh, for direct, uh,

1:06

blow that has some muscle damage at the surface of the bone.

1:09

A lot of contusion.

1:11

Uh, but you know, it's not, it's not always present.

1:14

It's really helpful if it's there,

1:15

but it's not always present.

1:17

Um, and the reason we can see this is that

1:20

as the tissues are compressed,

1:22

the muscle undergoes compression against the bone surface.

1:26

So the muscle edema may not be superficial.

1:29

It may be quite deep, uh, near the bone, uh,

1:32

as you see in this example.

1:34

Similarly, the hematomas don't have to be superficial.

1:38

They can be deep 'cause that muscle is being compressed,

1:41

uh, against the bone.

1:42

This is just a nice example of a patient

1:45

who sustained a direct injury, uh, to the thigh

1:48

who has a subacute hematoma.

1:51

Uh, and here you can see on the T one weighted images,

1:55

the high signal from the meth hemoglobin, which tends

1:59

to dominate around the periphery in a hematoma,

2:02

unlike in neoplasms,

2:04

where we'll often see the meth hemoglobin more centrally,

2:08

uh, due to tissue necrosis, uh, in the middle.

2:11

But certainly with these kinds of cases,

2:13

it's always a wise idea to follow them,

2:16

to make sure this, uh, resolves.

2:18

Uh, you know, if the patient has had no history of trauma,

2:21

then certainly this would be worrisome.

2:23

Uh, there's an underlying lesion, such a tumor

2:26

or a vascular malformation, uh, that's leading,

2:29

uh, to hemorrhage.

2:31

Here's just another example.

2:32

In this case, you can see the tendon damage associated

2:36

with it, with this weighty

2:38

and irregular, uh, uh, tendon in the, uh, semi menos

2:43

and the large, uh, hematoma

2:44

with the high signal predominating

2:47

around the periphery in this case, also related

2:50

to a direct blow to the posterior uh, thigh

2:54

hematomas are great to follow with ultrasound ultrasound's.

2:58

Also really good, good in the acute phase, uh, trying

3:01

to tell if the hematoma is drainable.

3:04

Uh, sometimes with large hematomas, uh, our, uh, uh,

3:07

orthopedic surgeons may attempt a drainage, uh, for patient,

3:12

uh, for patient comfort, trying to get some faster healing,

3:15

uh, within the, so ultrasound is really terrific

3:18

and it can be used serially, uh,

3:21

to follow these, uh, hemorrhages.

3:23

Now one thing to keep in mind is hematoma in the muscle is

3:27

not like that in the brain.

3:29

Uh, hematomas in the muscle are often associated with a lot

3:33

of parenchymal hemorrhage, such as we see in this example.

3:36

The hematoma is quite small,

3:38

but there's a lot of parenchymal bleeding nearby.

3:42

And you can think about the muscle really

3:44

behaving like a sponge.

3:46

It can absorb lots of blood with potential

3:49

for significant blood loss.

3:51

And I can tell you this is easy to miss

3:53

because that bright subacute blood, when it's high signal,

3:57

it's easily confused with fat

4:00

and you think it's just normal fatty striations.

4:03

But notice that on the fat saturated images, it stays bright

4:06

so you know it's not fat, and that's intramuscular bleeding.

4:10

This is a chronic bleed that has all kinds

4:14

of problems going on.

4:15

And this is something to be aware of in chronic bleeds, is

4:18

that the patients may start to form myositis specific hands.

4:23

This is a sort of a poorly understood, uh,

4:25

condition exactly why this this happens.

4:28

But the area of myositis specific hands in this patient,

4:31

we can see this low signal shell.

4:34

And I can tell you on Mr.

4:36

It's really hard to tell this low signal shell of bone

4:40

from the hemosiderin at the edges of a, uh, patient,

4:46

uh, who has a chronic, uh, hematoma.

4:49

So it's an easy, uh, diagnosis to overlook.

4:52

Uh, one thing that can help you is that these areas tend

4:56

to enhance very avidly if you give contrast.

5:00

And you should certainly look

5:01

for these if you see any calcifications on your x-ray.

5:05

Uh, this is another case from Enrique.

5:07

This was a professional of, uh,

5:09

soccer player from the Chilean team who had been kicked.

5:12

This is about five weeks, I believe, or maybe three weeks

5:16

after, uh, the injury.

5:18

And at this stage it's enhancing very avidly.

5:22

And this is the one month follow up, uh,

5:25

showing the characteristic ossification

5:28

of myositis Pacific hands,

5:30

but a difficult diagnosis to make during the Octa phase.

5:34

'cause the bone margins are really thin

5:36

and hard to tell from a fibrous layer or from hemosiderin.

5:40

Uh, this is a case given to me by Mark, uh,

5:43

Murphy at the a RP of a Myositis Certificants.

5:47

And you can see the huge amount

5:50

of inflammatory disease around this.

5:53

This is located in the lower subscapularis. I'm not

5:56

Sure if this patient had had a dislocation.

5:58

This is not my case or why it formed in this location.

6:02

Uh, but it's very nice example showing the

6:04

shell ossification.

6:06

And because of where he works, he has access

6:09

to the histology and pathology on, on these, uh, cases.

6:13

And this is a nice section from the periphery of it,

6:17

showing the mature ossification at the margins

6:20

of the myositis certificants.