0:00

This is a 45-year-old male who has a palpable soft

0:04

tissue mass along the dorsal aspect of the foot.

0:08

And let's put up the sagittal,

0:10

heavily water-weighted image.

0:13

This is not a difficult case, but you'll notice

0:16

that the lesion has a very tubular appearance,

0:20

going up and down for quite a distance.

0:24

And that suggests a specific diagnosis because of

0:27

its intimacy with the extensor tendon mechanism.

0:31

Which includes, in the axial projection,

0:33

the tibialis anterior tendon.

0:35

Next to it is the extensor hallucis,

0:37

and then the extensor digitorum and peroneus tertius.

0:41

You can see how this winds its way around

0:44

the tendon in the axial projection.

0:46

Let's blow that up a little bit.

0:48

It's fairly circumferential, but its true

0:51

tubular nature is not as apparent,

0:54

even on the coronal, as it is on the sagittal.

0:57

So, your first response to

0:59

this should be a tenosynovitis.

1:02

Then the next thing you ought to do is

1:04

call up something that is T1 weighted

1:07

and see if there's anything in it.

1:09

You know, is it purely proteinaceous fluid?

1:12

Is it pure fluid?

1:14

Or does it have synovium or blood inside it?

1:18

And it is not pure fluid,

1:19

because it's pretty close to muscle.

1:22

In fact, it's a little lighter than

1:23

muscle, so it's got to be proteinaceous.

1:25

Yet, it doesn't have any

1:26

synovitis or pannus inside it.

1:30

So your differential diagnosis for something

1:32

like this is mechanical tenosynovitis,

1:35

R.A. J.R.A.

1:36

38 00:01:37,080 --> 00:01:37,360

1:37

I showed you in this teaching set

1:40

a case of granuloma annulare that

1:43

involved the the tendon sheath.

1:46

Psoriasis with giant distention of the,

1:50

of the sheath can produce a sausage digit.

1:53

And then you've got weird things like amyloidosis,

1:56

which can occasionally occur in the tendon sheath.

1:59

But this is a mechanical tenosynovitis,

2:03

very straightforward, circumscribing the tibialis anterior tendon.

2:06

49 00:02:08,590 --> 00:02:10,449 Dr. P out on this one.

Tenosynovial Cyst

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0:00

This is a 45-year-old male who has a palpable soft

0:04

tissue mass along the dorsal aspect of the foot.

0:08

And let's put up the sagittal,

0:10

heavily water-weighted image.

0:13

This is not a difficult case, but you'll notice

0:16

that the lesion has a very tubular appearance,

0:20

going up and down for quite a distance.

0:24

And that suggests a specific diagnosis because of

0:27

its intimacy with the extensor tendon mechanism.

0:31

Which includes, in the axial projection,

0:33

the tibialis anterior tendon.

0:35

Next to it is the extensor hallucis,

0:37

and then the extensor digitorum and peroneus tertius.

0:41

You can see how this winds its way around

0:44

the tendon in the axial projection.

0:46

Let's blow that up a little bit.

0:48

It's fairly circumferential, but its true

0:51

tubular nature is not as apparent,

0:54

even on the coronal, as it is on the sagittal.

0:57

So, your first response to

0:59

this should be a tenosynovitis.

1:02

Then the next thing you ought to do is

1:04

call up something that is T1 weighted

1:07

and see if there's anything in it.

1:09

You know, is it purely proteinaceous fluid?

1:12

Is it pure fluid?

1:14

Or does it have synovium or blood inside it?

1:18

And it is not pure fluid,

1:19

because it's pretty close to muscle.

1:22

In fact, it's a little lighter than

1:23

muscle, so it's got to be proteinaceous.

1:25

Yet, it doesn't have any

1:26

synovitis or pannus inside it.

1:30

So your differential diagnosis for something

1:32

like this is mechanical tenosynovitis,

1:35

R.A. J.R.A.

1:36

38 00:01:37,080 --> 00:01:37,360

1:37

I showed you in this teaching set

1:40

a case of granuloma annulare that

1:43

involved the the tendon sheath.

1:46

Psoriasis with giant distention of the,

1:50

of the sheath can produce a sausage digit.

1:53

And then you've got weird things like amyloidosis,

1:56

which can occasionally occur in the tendon sheath.

1:59

But this is a mechanical tenosynovitis,

2:03

very straightforward, circumscribing the tibialis anterior tendon.

2:06

49 00:02:08,590 --> 00:02:10,449 Dr. P out on this one.

Report

Faculty

Stephen J Pomeranz, MD

Chief Medical Officer, ProScan Imaging. Founder, MRI Online

ProScan Imaging

Lesson

Foot & Ankle MRI Mastery Series: Pre-Course Activities

Lesson

Foot & Ankle MRI Mastery Series: Introduction

Lesson

Foot & Ankle MRI Mastery Series: Protocols and Sequences

Lesson

Foot & Ankle MRI Mastery Series: Anatomy

Lesson

Foot & Ankle MRI Mastery Series: Mid-foot Anatomy

Lesson

Foot & Ankle MRI Mastery Series: Case Review

Lesson

Foot & Ankle Masses

Tenosynovial Cyst