0:00

The next case is a 49-year-old woman with

0:04

second metatarsophalangeal joint pain in the

0:07

left foot for three months and no known injury.

0:10

So a proton density on your left and

0:12

a, and a gradient echo on your right.

0:15

How do we know it's a gradient echo?

0:16

The TE is very short.

0:18

The TR is very short.

0:19

The TE is very short, and

0:22

it says, T2 adage.

0:26

STAR stands for gradient echo,

0:30

and or susceptibility-weighted sequence.

0:33

And adage means additive gradient echo image.

0:36

Some of you may know, know it by the term merge.

0:40

Uh, medic.

0:42

M.

0:42

F.

0:42

F.

0:43

E.

0:43

If you are a Philips user and, um, you know,

0:49

let's do some scrolling now again when I hear

0:52

uh, that a woman has pain in her second toe.

0:58

I don't think of a lot of things.

1:00

You know, I've got a pretty

1:01

limited differential going in.

1:03

So in other words, you know, I'm like a

1:05

clinician going into the exam room examining the

1:08

patient except I've got imaging, which frankly

1:13

is as good or better than any physical exam.

1:15

Let's face it, you know,

1:17

when you're in the ER and you suspect

1:19

appendicitis, you don't do this anymore.

1:21

You don't palpate the right

1:22

lower quadrant very much.

1:23

Maybe for five seconds, you go

1:25

right to CT and you get the answer.

1:28

So in the, in the days of my

1:31

training, that was considered

1:33

bad medicine.

1:34

Today, that's considered good medicine.

1:37

So you see how things have changed and evolved.

1:43

disease, stress fracture, which isn't usually

1:47

the second, it can be, but I mean, it's not

1:49

isolated to the second, set a better way.

1:52

And, and a plantar plate problem.

1:54

Those are the three things on my mind.

1:57

And one thing I will do is I'll look at the

1:59

long-axis coronal, and I will make sure that

2:03

there isn't a long, a second long metatarsal

2:06

head, which predisposes to all kinds of

2:09

problems and we'll do that in a moment.

2:13

I think it would be helpful if we picked out

2:15

maybe, um, one of these sagittals and then

2:21

cross-referenced it so we can see where we are.

2:23

So let's cross-reference it with this.

2:26

This is a long-axis axial view that looks more

2:29

coronal and, um, you know, that'll kind of

2:33

get you oriented so you can see where you are.

2:36

For instance, here's a line.

2:37

I know it's hard to see on your screen.

2:39

Right now we're at the fourth.

2:41

So let's go over to the fourth.

2:42

We're just starting to make it over there.

2:43

Let's go to the third.

2:45

Here's the third.

2:47

And so far in the third, which by the way,

2:50

isn't where the pain was, it was in the second.

2:53

But, you know, we've got a nice reference.

2:56

We've got the plantar plate.

2:58

Of the third here, the plate separates

3:01

from the flexor tendon right there.

3:04

So it goes right up on there now.

3:05

Sometimes you'll have just a tiny

3:06

little nubbin of a defect right here.

3:10

It's either a little sulcus or recess like that,

3:13

or sometimes it's even a little deeper due to

3:15

wear and tear, where you get some plantar plate.

3:20

Separation from the cartilage attachment so it

3:23

gets a little frayed, and I don't mind that,

3:26

but I don't want to see a through-and-through defect.

3:29

I don't want to see any retraction of

3:31

this tiny little structure right here.

3:34

And then remember also that it is, it goes across.

3:38

So if this is the metatarsal head.

3:41

And my right hand is the plate.

3:44

The plate has width, right?

3:45

It goes from side to side.

3:49

So it has a medial-lateral orientation,

3:51

just like the rotator cuff of the shoulder

3:54

has a retraction dimension going this way

3:57

and a length going anterior to posterior.

3:59

So, you know, you're 3D thinkers,

4:01

you're the best 3D thinkers on the planet.

4:05

And, you know, we start to look

4:07

around on this long-axis view and we

4:09

immediately realize we got a problem.

4:13

And I don't know if you've seen the

4:13

problem yet, but I want you to look.

4:16

Because some of you who looked at this

4:18

case maybe didn't see the problem,

4:20

the patient has micro instability.

4:23

And how do we know that? Because the collateral

4:28

ligament on the lateral side is deficient.

4:32

Here's what it should look like.

4:34

And here's what it does look like.

4:37

So that is either allowing the total wiggle

4:40

or something else allowed the total wiggle and

4:43

degenerated that collateral ligament, which,

4:47

you know, chicken and egg, which came first.

4:50

I don't know the answer to that.

4:52

I think that's a good question for our

4:54

foot surgery colleagues but I don't

4:56

think they'll know the answer to it either.

4:58

So now let's go back to our third.

5:01

Mandatory.

5:01

So we've got a great plate and

5:04

now we're coming out of the plate.

5:05

Actually still more plate.

5:06

My apology.

5:07

We're still in the plate,

5:09

right on the free edge of the plate.

5:10

It's gorgeous.

5:12

The cartilage surface.

5:14

Is gorgeous; looks just fine.

5:16

Yeah, there's a little spur,

5:17

but you know, she's 49 years old.

5:19

She's probably been in a few high heels in

5:21

her day, and I don't mind that; that's okay.

5:25

Now, that's a little very early away; just

5:28

about everybody in their 50s has got that.

5:31

Now we start to move over to our collateral;

5:33

it's awfully swollen on our sagittal gradient

5:36

echo, and why am I leaving the gradient echo up?

5:39

Because it has very robust signal to noise.

5:43

And even though I can't see the slice

5:45

thickness on this one, let me say,

5:47

I think it's going to be about 1.2 millimeters.

5:49

140 00:05:50,555 --> 00:05:51,885 So it's very thin.

5:52

Even this T2, TE3000, TE84 is still

5:57

pretty thin at two and a half millimeters.

5:59

So this is going to be ones.

6:01

Yep.

6:01

I can see it right here.

6:02

1.4 is what it is.

6:03

148 00:06:05,114 --> 00:06:06,505 So let's keep going into the

6:06

center of our of our plate.

6:08

Where is the plate?

6:10

Once again, we've got that, uh,

6:13

mashed potato thing going on here.

6:15

Look at this squiggly wiggly

6:17

morass of tissue right here.

6:20

And there's no plate.

6:21

We're almost right to the

6:22

center of the metatarsal.

6:24

See, there's our line.

6:26

Things are looking awful.

6:27

Let's go back over to this

6:29

media to this lateral side.

6:31

We never, never come up with a plate.

6:34

So we're all the way to the midline.

6:36

No plate.

6:37

And now we're going across to the other side.

6:39

And we see a semblance of a plate right there.

6:42

That's kind of rolled up in a ball, and maybe

6:46

when you get all the way out to the free edge,

6:48

there's a little bit of attachment to the plate.

6:50

So, the plate tear is full depth.

6:54

It's almost complete from lateral to medial.

6:58

It's associated with deficiency

7:00

and chronic tear of the lateral

7:03

collateral ligament of the second MTP.

7:07

And now let's work our way into the first.

7:10

Now, we didn't get there, but the first metatarsus,

7:14

I just wanted to point it out medically.

7:17

Nobody, you know, who is an adult woman who's

7:20

been walking around in elevated shoes

7:22

is going to have a normal first plate.

7:24

They're always degenerated.

7:26

They're always a little fibrillated.

7:28

Their attachments are often, uh,

7:31

detached in a microscopic fashion.

7:33

So you're going to see some signal there.

7:35

So unless you're dealing with an athlete with

7:38

turf toe, etc., I don't get terribly excited

7:42

about first plant or plate irregularities.

7:46

Um, unless I've got some other

7:47

really strong supportive findings.

7:49

So we've got exactly what we expected.

7:53

Um, we have a second metatarsal plate disruption

7:57

and another little key finding, which was

7:59

described by my friends, uh, Dr. Go, I think

8:03

Rolando Go from UCLA and a beautiful paper at

8:07

a time when it was completely unrecognized.

8:10

Um, he said

8:13

that when you see this circumferential ring of

8:16

fire around the second metatarsal head, um, and

8:21

you don't see free birds or a, or a fracture,

8:25

then it's a plantar plate tear to proven otherwise.

8:28

One last caveat is if you have that swelling,

8:33

and you see the plantar plate present, I would

8:36

recommend you do the following, and I know you

8:38

can see me, take the toe, bring the patient

8:41

back, dorsally tape the toe. They may scream a

8:45

little bit. You may have to give them a little

8:47

bit of sedation or pain medicine. Tape the toe

8:50

backwards, and very often you'll see the plantar

8:53

plate pop right off. It's just kind of laying

8:55

there in the passive position. These dorsal

8:58

stress tape views will help you a great deal.