0:00

It's a 58 year old woman complaining of right posterior hand

0:05

pain and a history of carpal tunnel, uh, surgery.

0:10

And most of you correctly picked up on some changes in the flexor

0:15

macula and some changes in the peritus soft tissues. For instance,

0:19

these circumferential areas of high signal represent fluid

0:24

in the, uh, extensor sheaths. And if you look very carefully,

0:28

there's a similar phenomenon anteriorly. This is real.

0:32

There's some fluid in the flexor sheaths. Now,

0:35

sometimes when you have fluid in say, rheumatoid or related conditions,

0:39

you'll see actual synovitis. Um,

0:43

most of these sheaths are synovial lined in the foot.

0:47

Not all the tendon sheaths are synovial line. For instance,

0:50

the Achilles is not synovial line. So that can get a little bit confusing.

0:55

What's also confusing about this case is that the,

0:58

the history of posterior wrist pain kind of dominates the

1:03

introduction. And so you would have to come up with this explanation,

1:07

namely that there's teno synovial or peritendinitis fluid accumulation in the

1:11

extensors. If you're gonna correlate with the history, there's also,

1:15

and if you correlate with the T one on your right,

1:18

the fat weighted image right here, you'll see that the capsule is distended.

1:22

And this little gray sliver and this little sort of round sliver right

1:27

here, uh, that's what very mild, uh, synovitis looks like. Now,

1:32

synovitis does not automatically mean you have, um,

1:35

inflammatory arthropathy 'cause you can get mechanical synovial hypertrophy.

1:41

And likely that's what's happened here.

1:43

A lot of you are looking at this round object in the capitate,

1:47

which most people have. It is a, because the capitate is a central bone,

1:53

it is subject to friction from all sides.

1:56

So this is a friction induced intraosseous ganglion. Uh,

2:01

you'll see them on conventional radiographs all the time in the wrist.

2:04

It's of no consequence.

2:06

I often comment on it just so people don't get excited about it,

2:09

and sometimes I forget to 'cause I see it in almost every case,

2:14

and it's not really relevant to the patient's, um,

2:17

clinical syndrome 99% of the time. Now,

2:21

the main finding in this case is not on the dorsal surface,

2:25

which makes it challenging. And, um, perhaps explains why, uh,

2:29

quite a few of you did not, uh, tap into the major finding.

2:35

The major finding is that the patient has had a carpal tunnel release.

2:40

And I'm gonna use my pen here.

2:43

One of the descriptors for carpal tunnel release is that you get a

2:48

bhap fibro fatty cleft. So there's the B, there's the middle of the B,

2:53

and there is the other part of the B. Um, and

2:58

Then the cleft is right in the middle.

3:01

You can kind of see that on the T one weighted image,

3:03

there's the b there's the fibro fatty cleft, there's the fat,

3:07

and then there's the other portion of the b. Now around the median nerve,

3:13

which is right here, you should have a rim of fat on the T one.

3:18

So that is lost. It might say no big deal,

3:21

somebody was in there releasing the carpal tunnel space. Of course,

3:24

you're gonna get a little inflammatory tissue there, and that's okay. You know,

3:28

that by itself would not bother me. Now the nerve is normally gray and,

3:33

and there is the gray nerve.

3:34

That's what the nerve should look like on the T two weighted image.

3:38

That's what it should look like on the T one weighted image,

3:41

although it is obscured by the post-surgical granulation tissue.

3:44

Let's keep scrolling as we get to our fibro fatty cleft where we did

3:49

a flexor vernacular release, which by the way,

3:52

you can do under ultrasound now non-invasively. And, uh,

3:56

that is done in several major centers around the United States,

4:01

uh, popularized by, um, Dr. Nazarian in, in Philadelphia. And,

4:06

and then wait a minute, all of a sudden, and without warning,

4:09

look what happens to our median nerve. It goes bright on us like a light bulb.

4:13

Now it is not supposed to do that. Not only does it go bright, it gets bigger.

4:19

So when I'm looking at nerves longitudinally,

4:21

and right now I'm looking at them in cross-section,

4:25

I don't wanna see the nerve do this.

4:29

I don't wanna see the nerve get bulbous, almost like it has an aneurysm.

4:33

And that's exactly what's happening here. So the nerve is swollen.

4:37

I also do not wanna see the nerve go, go bright on me.

4:43

I don't wanna see it go white on me, so I don't wanna see this.

4:46

And that's exactly what's happening here.

4:48

So there has been a focal injury to the median nerve.

4:53

It's not transected, but it's injured. Now here's, here's a weird thing.

4:58

Sometimes when the nerve has been injured on a chronic basis,

5:03

and this applies no matter where you are in the body, we're talking Mr.

5:07

Neurography. Now sometimes the nerve will get smaller,

5:12

so-called neuro esis of the nerve. So the nerve will,

5:16

will be indented almost like it's scarred, it'll shrink.

5:19

And very often when this shrinkage occurs, what do you get at that site?

5:23

You don't get white, you get black or dark gray,

5:28

something like this.

5:33

And that's paradoxical fibrosis o o of the nerve.

5:37

So these are the things you should be looking for. Swelling with high signal,

5:42

not on a stir, not on a spur, not on a gradient,

5:46

but on a T two spin echo,

5:47

which this is so bright signal in the nerve on a T two

5:52

spin echo without nerve transection is consistent with a

5:57

traumatic neurotic phenomenon of the median nerve at a site of carpal tunnel

6:02

release. Now, when I look at carpal tunnel release,

6:05

I wanna see that that cleft go all the way to the hook of the handmaid.

6:08

And it does.

6:10

And then I wanna see it back at the level of the pisiform and maybe not so much.

6:15

So they,

6:16

they probably could have taken the release back a little further to the pisiform

6:20

level, but I, I'm more concerned that they,

6:22

they don't release it at the handmaid level. And they did.

6:25

So this could have had a little more release, more proximally,

6:28

and that probably should have been commented on.

6:31

But no doubt this is a major finding.

6:35

Now what do you do about it? There's not a lot that you can do at this point.

6:39

Um, you can try nerve stimulation, you can inject steroids,

6:43

being very careful not to hit, hit the nerve directly.

6:46

Now another thing you can see here is that there is in the deeper fibers of the

6:50

thenar eminence, there's some atrophy and fatty replacement.

6:54

Now let's keep going on these axials and see if there's anything else.

6:58

We've already established that there's flexor peritendinitis or teno

7:03

synovitis. There's extensor the same thing.

7:07

Here are the extensors and they're all,

7:09

they've all got a little fluid around them.

7:11

And here's a little pearl when you fracture the wrist,

7:14

because the periosteum of the dorsum of the wrist communicates with the sheath,

7:20

the sheaths will always distend.

7:23

So you shouldn't call that tina synovitis,

7:25

you should call it reactive fluid secondary to a fracture.

7:29

Now this patient doesn't have a fracture that doesn't apply here,

7:33

but that's just a pearl for the future.

7:36

And you can see a fair amount of fluid around the extensor carpe ris.

7:40

The extensor carpe ris sub sheet is right there and it stays, you know,

7:45

pretty nicely where it's supposed to. If we go a little more towards the groove,

7:49

we didn't get there, but it's in, it's in the right place.

7:53

Now let's turn our attention to the coronals,

7:57

see if there's anything there of interest. So let's take a look at

8:03

the triangular fibrocartilage for a moment.

8:08

And I admit it's a little difficult to see at low field,

8:11

but there it is right there.

8:12

And you can see there's some tissue thickening right here.

8:15

Now this right here is hyland cartilage. That's normal,

8:19

but this tissue thickening is abnormal and there's fluid in the distal radial

8:24

ulnar articulation.

8:26

So this patient has a chronic central third perforation

8:30

of the triangular fibrocartilage. Once you see that, you should look for ul,

8:35

no malacia doesn't have it.

8:37

You should look for lu triquetral ligament tear doesn't

8:42

have it, uh, to see if the patient has, you know,

8:44

some type of ulnar lunate abutment syndrome.

8:50

Let's see, what else do we have in this case? We've got some generalized carpal,

8:54

uh, capsulitis that, that fluid that's present there.

8:57

That's a term I use frequently unless I see frank synovitis.

9:01

There's our intraosseous friction related ganglion. Uh,

9:05

of the capitate.

9:07

We've already established that there is fluid in the D R U J,

9:11

there's some fluid in the carpus, there's some fluid in the flexors,

9:14

there's some fluid in the extensors and there's fluid in the metacarpal

9:19

phill joints. There, there, there, there, and there.

9:23

The white stuff shouldn't have that either. So why is that there?

9:27

I'm not really sure. I don't know the answer to that. But if this, um,

9:33

is, is a woman, which it is, and I I didn't have another explanation,

9:38

I would absolutely vet this patient for a rheumatologic disorder.

9:43

And remember, people with rheumatologic disorders, including RA,

9:48

will get secondary carpal tunnel syndrome. Now,

9:52

that wasn't mentioned here and it probably should have been in, in the,

9:55

in the official report. So that, that is something to consider.

9:59

There's no good reason why this patient should have fluid in the carpus,

10:03

fluid in the sheath and fluid in the cps.