0:01

All right, so let's move on to our next case,

0:05

a companion case.

0:08

Um, this is a 60-year-old man

0:11

who had chronic left ankle pain.

0:15

So here I'm showing you the axial T ones, axial pd,

0:18

fat suppressed, and then the coronal T one.

0:22

And let's also pull up the sagittal T ones.

0:29

So just like in our last case

0:32

as we're scrolling on the axial images, um,

0:36

here it looks like the perineal tendons are dislocated from

0:40

the retro mall groove.

0:42

In this case, it looks like both brevis

0:45

and longus are laterally dislocated.

0:49

Um, here I'm trying to search for something

0:52

that resembles a normal superior perineal ret macular.

0:55

I, I don't really see any normal tissue overlying the

0:59

perineal tendons in this location.

1:03

Um, one

1:04

of the questions I think somebody asked in the pre-course

1:07

survey was how you distinguish acute from subacute, um,

1:11

from chronic injuries.

1:12

I think the question was about ligaments,

1:14

but I think we can apply similar principles

1:17

to the retina aula as to the ligaments.

1:20

Um, usually if I'm seeing a lot of 10 synovial fluid

1:24

or soft tissue edema in the region of the pathology,

1:27

I would favor it to be a more acute or recent injury.

1:30

And then if I see a structure that's missing or thickened,

1:35

but I don't see a lot of surrounding soft tissue edema,

1:38

then I would favor the injury to be more chronic.

1:41

Uh, here I think we have another good, uh,

1:45

reason why we should suspect

1:46

that the RET macular injury allowing the

1:49

dislocation is more chronic.

1:50

We can see that the calcaneus is, uh, previously fractured,

1:55

now healed, uh,

1:56

but mal united, uh,

1:59

if we look at our sal images, we can see, um,

2:04

if we tried to measure a boar's angle,

2:06

it would be quite flattened.

2:08

And then looking at our posterior calcaneal facet,

2:10

there's some residual articular surface incongruity from the

2:14

way that the fracture healed.

2:18

If we look at our coronal images, you'll see that the, uh,

2:23

calcaneal body looks laterally extruded, um,

2:27

healed in this, um, deformed position,

2:30

and that's causing some narrowing of the normal space

2:34

between the distal fibula and the calcaneus.

2:38

And then pulling up our coronal fluid sensitive images,

2:42

you'll note that there's a little bit of cystic change

2:45

and edema, uh, at the opposing surfaces of the distal fibula

2:49

and the calcaneus.

2:51

So this patient has a component of, um, sub

2:55

or lateral hind foot impingement here.

2:59

So injuries to the CPA Peral reticulum, um,

3:03

for example in our last case, those are usually related

3:06

to a sudden dorsiflexion injury

3:09

or sometimes an inversion injury.

3:12

But they can also be associated

3:13

with calcaneal fractures like the one

3:15

that we're seeing here.

3:17

Other causes of injury

3:19

to the perineal reticulum are gonna be related to fractures

3:23

of the distal tibia.

3:25

Um, sometimes they can occur if you have a congenital foot

3:28

deformity or, uh, sometimes you can have injuries

3:32

because you have crowding of the retro mall or groove.

3:37

So for example, if you have an anomalous, uh,

3:40

peroneous Cortes muscle, like the one that Dr.

3:43

Resnick showed in his previous lecture,

3:45

or if you just have a low lying peroneous brevis muscle

3:49

belly that's crowding that space, it can predispose you

3:52

to these RET macular injuries.