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Let's take a look at this 24-year-old professional

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athlete, large man, inversion injury with

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the foot in a somewhat neutral position.

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Let's start out with the axials because

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that's where a lot of the information is.

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And I'm going to show you this massive

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anterolateral hematoma, which shows up as an area

0:25

of clinical ecchymosis, and that is totally scary.

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Okay, now let's do what I would do if I was

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sitting alone by myself reading the case.

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And I'm going to put up all my sagittals.

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So I've got three sagittals.

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You probably only really need two.

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And I'm going to blow them up just a little bit.

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On the left, in the left corner,

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where in the blue trunks, is my

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proton density fat suppression image.

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My all-purpose sensitive sequence to

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look at where all the, uh, all the hot

1:00

spots are, and there's a lot of them.

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The foot is massively swollen on the lateral

1:05

side, but I'm particularly interested

1:07

in fractures and the fracture pattern.

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I have very little signal change in the

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posterior malleolus because if I did,

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if I saw periosteal swelling, periosteal

1:18

hematoma, or fracture back here, I'm starting

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to think more of a high ankle-type injury.

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I am also scrolling around, I'm going over

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to my gradient echo and my T1-weighted image.

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To see if I've got any bodies inside

1:32

the joint on the gradient echo image.

1:34

Yes, there is a large, uh, large

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os trigonum that, that fractured.

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Uh, or, or a lateral talus process that

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fractured, maybe an old Shepherd's fracture.

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And then on the far right,

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I've got my T1-weighted image.

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And that in particular is the one

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where I'm scrolling and trolling, to

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use a popular social media word. I'm

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trolling for osteochondral defects.

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And I don't have any.

2:00

Okay, that's good.

2:02

Now that I've kind of worked my way through the

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sagittals and I've also done a pretty brief but

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comfortable inspection of the peroneae, which

2:11

are often injured in ankle sprains, which we

2:15

are very suspicious of because of the hematoma.

2:18

I'll quickly slide over to the

2:20

medial side and look at the retro and

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inframalleolar posterior tibial tendon.

2:26

It looks very good.

2:28

It looks excellent.

2:29

Okay, while I'm at it, I've got a bird's

2:32

eye view of the sinus tarsian canal.

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The canal's more medial, more of a hole.

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The sinus tarsi is more lateral, more open.

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And in the sinus tarsi, I've got trouble.

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Big trouble.

2:44

I've got a lot of swelling.

2:45

I've got some irregular fibrillated dark

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tissue that suggests that the subtalar

2:53

ligamentous anatomy has been affected.

2:57

by whatever happened to this gentleman.

3:00

Okay, before I go back to my

3:02

axial, let's put up a coronal.

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Now, what are we going to get out of the coronal?

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This is a heavily fat-suppressed, water

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weighted coronal image, and we'll get

3:14

another perhaps better view of the

3:16

bones, and especially of the talar dome.

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Talar dome, perfect.

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But we do have an injury to the bone, specifically

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the distal aspect of the talus, right up against

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the navicular, and what are we going to call this?

3:32

Well, it was pretty hard to

3:33

see in the other projections.

3:35

Let's look at the T1 before

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we decide what to call it.

3:38

We missed it on our first scroll.

3:41

It was there.

3:42

Nothing's displaced.

3:44

There are no discrete lines.

3:46

There's very slight flattening or deformity.

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So we are going to call it

3:50

a microtrabecular injury.

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Or you could go so far as to use the

3:54

F-word, microtrabecular fracture.

3:57

But nothing more than micro.

3:59

It's intramedullary, it's enchondral, it

4:02

involves the spongy bone, nothing is avulsed.

4:05

You'll trace the cortex to make

4:07

sure that it's even and smooth.

4:10

It's a little bit edematous here because

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it's gray, but nothing's pulled off.

4:15

And even if there was a small fleck, that

4:17

wouldn't affect the management in this case.

4:21

Alright, let's go back to

4:21

our single coronal image.

4:25

Wow, look at that collection of blood.

4:30

We're in trouble.

4:32

What else are we going to get

4:33

out of the coronal projection?

4:34

Thank you very much.

4:35

We'll get the deltoid.

4:37

The deltoid is almost always swollen

4:40

in somebody with an inversion injury.

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Because when you invert, you're

4:45

gonna compress the deltoid.

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Much like you would compress an accordion.

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And when you bleed into that compressed

4:51

deltoid, people call that a tear.

4:55

Now, deltoid injuries shouldn't

4:57

concern you all that much.

4:58

You shouldn't fret over them because

5:00

we almost never operate on them.

5:02

They almost always heal themselves.

5:04

And in fact, an operation on

5:06

the deltoid may be a bad thing.

5:08

So you might say, deltoid swelling,

5:11

contusion, sprain, hematoma.

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Yes, it's a little busy, but if you're

5:15

starting to really drill into the deltoid

5:18

in an inversion injury, you're probably

5:20

wasting your and other people's time.

5:23

Let's go back to the other

5:25

strengths of the coronal.

5:27

Another strength of it is to look

5:29

at the calcaneofibular ligament.

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It's a very tough ligament to see.

5:33

Now that right there is not a deltoid.

5:37

The calcaneofibular ligament.

5:40

It actually masquerades as the course

5:42

of the ligament, but it's going to the

5:44

Achilles, that's not the calcaneofibular ligament.

5:49

That's a deep bundle of another ligament.

5:54

So it's, it's not the one

5:56

that we're searching for.

5:56

Where's the one we're searching for?

5:58

Right here.

6:00

And it's gonna course towards the

6:02

posterior aspect of the calcaneus.

6:04

It ends right there as a stump.

6:07

We can't follow it any further.

6:09

So our calcaneofibular ligament, even

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though we're neutrally, sorry, even

6:13

though we're slightly plantar flexed, in an

6:16

optimal position to see it, we don't see it.

6:19

We don't see it because it's ruptured.

6:21

What else can we glean from

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this coronal projection?

6:24

What's going on over here?

6:25

Well, we said there's blood, but normally

6:28

there's an infralateral retinaculum.

6:30

So let's talk about the subtalar ligaments.

6:34

Immediately, we've got the

6:36

talocalcaneal interosseous ligament.

6:38

It's intact, it's thin, it's

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dark, it's delicate, it's normal.

6:43

The next ligament over, probably

6:45

the most important stabilizer of the

6:47

subtalar space, the cervical ligament.

6:51

It's fat, it's irregular, it's

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ragged, it's nasty, it's torn.

6:58

He's got a subtalar injury.

7:00

Now let's go over to the next group, the extensor

7:03

retinaculum, which contains the stem ligament

7:06

and also known as the frondiform ligament.

7:11

Oh, it's filled with blood and we can't

7:12

see anything that is linear and obliquely

7:15

coursing over on the lateral side.

7:17

It's fat, it's torn.

7:19

And the blood and fluid of the subtalar

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space coming out to mix with the large

7:26

hematoma on the lateral aspect of this

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patient's ankle that's going up and down.

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So now it's time to go back to the axial

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projection and see what else is going on.

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And I'd like to do that in a separate vignette

7:43

and save you some time so you can turn this

7:44

one off and move on to part two if you wish.