0:00

So let's move now to the areas that we're going

0:03

to discuss in the Pine Foot.

0:05

When, when you look at, at this algorithm

0:09

for diagnosing etiologies of heel pain,

0:11

it's really remarkable how many different things can,

0:15

can cause heel pain and,

0:16

and we imagine how skilled our clinicians have to be

0:20

and why the role of imaging becomes so very important

0:23

with respect to identifying what's causing

0:26

hind foot or heel pain.

0:27

Don and Karen have already talked about some of these.

0:30

We're going to focus on plantar fasciitis,

0:34

posterior impingement, and the haglin deformity.

0:37

Uh, as we think about, um, a few different areas

0:40

that we commonly encounter with respect

0:43

to hind foot or heel pain.

0:45

So when we're thinking about the plantar fascia,

0:48

we've got the central and lateral segments as well

0:51

as a medial segment, those emanating from the

0:54

calcaneus moving distally as we think about pathology

0:59

that we encounter here, common to see

1:02

that in the central segment record.

1:04

One interesting an uh, anatomic detail is that

1:08

as you think about the achilles tendon,

1:10

there's actually a component of what has been described

1:13

as the peron

1:15

or some fibers of the Achilles

1:18

that are continuous along the posterior margin

1:20

of the calcaneus

1:22

and contribute to the central cord plantar fascia.

1:26

Now this is probably familiar to you

1:29

because there's a similar system when you think about the

1:32

pre patellar quadriceps continuum

1:35

with the patella in the knee.

1:39

So very similar. You could almost consider the calcaneus

1:42

here as a patella with this

1:44

achilles coming across the continuation, um,

1:48

across the OSS osteo structure to contribute

1:50

to the plantar fascia.

1:52

So this gives us sort of link within the kinetic chain

1:56

and structural change of

1:58

what happens when you've got Achilles pathology

2:01

plantar fascia pathology all the way up

2:03

as you consider what's happening with the gastroc and sous.

2:07

So that sort of makes sense I think when we consider

2:10

combinations of pathology

2:11

that we encounter across those areas.

2:15

So the plantar fascia

2:16

and Hein foot four foot alignment is so interesting

2:20

and we're not gonna talk about, um, Hein foot valgus

2:24

and pest plaintiff, but, but that's super interesting

2:27

and I wish we had time to get into it,

2:29

but maybe at another course.

2:31

So when you're thinking about a lateral view of the foot

2:34

and mechanical axis of the foot,

2:36

think about the hind foot axis coming along the course

2:40

of the calcaneus through the tus,

2:42

and then the angle that that makes

2:44

through the midfoot and the forefoot.

2:46

If we were to construct a sort of triangle, the way

2:49

that we would maintain this arc is

2:52

through the plantar fascia that's sort of been referred to

2:55

as a tie beam, this whole thing, the windless mechanism.

2:59

So you see that the plantar fascia becomes a very important

3:03

secondary stabilizer of the arch of the foot.

3:06

Remember we talked about that longitudinal arch?

3:09

You have to have an intact plantar fascia to hold together

3:13

this construct of the hindfoot axis in the full foot axis.

3:17

So super, super interesting.

3:19

So when you think about dorsi flexion, you kind

3:23

of wind the plantar fascia.

3:25

It results in this appearance of the foot.

3:27

And of course when you think about insufficiency

3:30

of the plantar fascia as one

3:32

of the arch supporters, what happens?

3:34

Well, that's the plaintiff's alignment

3:37

and one of the three major arch supporters of that, again,

3:40

that longitudinal arch of the foot is the plantar fascia,

3:44

the other two spoiler alert spring ligament

3:47

and the PTT maybe for one of our future talks together.

3:51

So again, this idea of a windless mechanism

3:53

as you dorsi flex the forefoot.

3:57

Just an example here of the specimen photograph,

4:00

low signal intensity, achilles tendon,

4:03

perhaps seeing maybe some of those fibers

4:05

of the perone contributing in here,

4:07

that nice thick central cord plantar fascia.

4:11

As we look in the short axis dimension,

4:14

you can see the proximal two distal components showing the

4:18

central and lateral cords.

4:21

And of course, when we think about SEPTA arising from the

4:24

junction of the central portion

4:25

with medial lateral portions,

4:26

we divide plantar musculature into medial lateral

4:30

intermediate groups.

4:32

Remember that goes all the way into, uh,

4:34

the distal aspect of the foot.

4:36

And when you think about plantar compartments, the level

4:38

of the forefoot, you've got the great toe separated from

4:41

second, third, and fourth metatarsals from the fifth MTP.

4:46

And when you have inflammatory changes

4:49

that affect the great toe

4:50

or that affect the fifth toe, uh,

4:52

sometimes you'll see this like very well delineated

4:55

inflammatory change that surrounds first MTPR fifth MTP.

4:59

And it's this beautiful example of

5:01

how plantar compartments really extend all the way

5:04

distally into the flow foot.

5:07

So as we're thinking about plantar fasciitis,

5:10

we've got some clinical diagnostic criteria, fixed heel pain

5:14

that's aggravated after morning rise

5:17

or waking up in the morning prolonged and strenuous activity

5:20

and can relieve with rest or unloading.

5:23

So the etiology, as you can imagine, can be mechanical

5:26

and traumatic, degenerative or systemic in nature.

5:30

Um, and this has been described as the most common form

5:34

of heel pain in adults.

5:37

So here you're seeing a very thick

5:39

and slightly irregular central cord plantar fascia.

5:42

As you look in the short axis images

5:46

here in a different patient, you're seeing the thickness,

5:49

some altered signal intensity,

5:50

but something we always need to look

5:52

for the high signal intensity in the soft tissues

5:55

surrounding that central

5:57

Cord extending here to the lateral cord

5:59

and in some cases involving the muscle.

6:02

I also always take a careful look at the plantar fat pad

6:06

as well for altered signal intensity, both, um,

6:10

low signal intensity that's isolated on the non-fat

6:13

suppressed as well as low and high signal intensity.

6:16

So remember that the fibrosis in the fat pad can also cause

6:20

abnormal mechanics back there and can lead to pain.

6:26

As we're thinking about plantar fasciitis,

6:28

there have been some descriptions in the

6:30

literature of measurements.

6:32

I have to say I'm not a big fan of measuring things.

6:35

I'd rather look at the caliber of the structure, um,

6:39

look at it at the emphasis, follow it

6:42

to see if there's caliber change, then look

6:44

to see if there's osseous and thise changes

6:47

or altered signal intensity.

6:48

Those things vary very important.

6:51

So I'm not a fan again

6:52

of measuring in this case altered T one signal intensity

6:56

osseous irregularity.

6:58

As we move to the fluid sensitive sequences, here,

7:01

you see increased signal intensity, but it does not rise or

7:05

or increase to the level of simple fluid.

7:08

Look at the plantar fat pad, e faced signal here,

7:12

associated high signal here.

7:14

And then of course in the image on the bottom we're seeing

7:16

an enthesophyte that's common in patients

7:20

who have quote unquote plantar fasciitis

7:23

or the clinical entity of plantar fasciitis.

7:25

And we'll talk about the enthesophyte in greater detail.

7:29

And just shortly, so in this case,

7:33

as you look at the central core plantar fascia,

7:35

this was an acute tear

7:36

or rupture, completely discontinuous, no retraction,

7:40

and likely, uh, there was some degree of degeneration here

7:43

with then a superimposed load

7:46

or traumatic event that resulted in the rupture.

7:48

You see a little bit of thickening here.

7:50

The distal aspect of that central core doesn't look too bad.

7:54

And of course some high signal intensity in the soft

7:56

tissues, no altered signal intensity in the marrow.

7:59

And we do have some altered signal intensity within

8:01

the plantar fat pad.

8:04

Here is the, uh, discussion of inviso formation.

8:09

Don was the senior author on this beautiful paper

8:12

that looked at anatomic pathologic sections

8:15

and really kind of put to rest the idea of

8:17

where the enthi light is.

8:18

In the majority of cases,

8:20

it does not extend into the plantar fascia,

8:23

but rather it's associated with the muscle

8:25

and the muscular attachment there.

8:27

However, that phy has certainly been associated with,

8:32

uh, pain in, in the setting of, uh, its presence

8:36

and also plantar fascial thickening and structural change.

8:39

And we're going to talk about the association of a nerve

8:43

that is in, uh, very close proximity to the plantar aspect

8:47

of the calcaneus and the plantar fascia.

8:49

So certainly that could place mass effect on the nerve

8:53

that passes, uh,

8:55

Adjacent to it here an example

8:59

and a nice illustration showing, uh,

9:01

the tibial nerve here dividing into medial

9:04

and lateral plantar nerves.

9:06

And then we've got the inferior calcan nerve

9:09

that crosses from the medial to the lateral side.

9:13

Should see that here in the region of the calcaneus

9:17

between it and the plantar fascia.

9:20

So in this case you see

9:21

that the fat is a face in that region.

9:23

We don't see high signal intensity within their nerves.

9:26

Sometimes we'll see it in morphologic changes.

9:28

Well, although it's a very tiny nerve.

9:30

But here you see gross thickening of the plantar fascia,

9:34

you see a portion of a plantar phy.

9:37

And the secondary findings here of the impingement

9:39

or mass effect on that inferior calcaneal nerve is

9:43

to see fatty infiltration

9:45

or atrophy of the abductor digi plenty,

9:47

which we do in this case.

9:49

So when you see central cord

9:53

or plantar fascial abnormalities and phy formation

9:56

or you see altered signal intensity within the nerve,

9:59

be sure to do this secondary check

10:01

of looking at the musculature.

10:04

Uh, looking in the coronal imaging plane

10:05

or short axis plane through the hind foot is a nice way

10:08

to be able to do that

10:09

and you'll easily identify areas of volume loss or fatty

10:13

and filtration fibromas with respect

10:18

to plantar fascia

10:19

and pain in the plantar fascia can certainly occur.

10:22

So remember when I said I don't necessarily like

10:24

to measure plantar fascia, but look for caliber change.

10:27

So in this case,

10:29

clearly a distinct change in the overall morphology

10:32

and caliber of the central core plantar fascia.

10:35

Nice linear, low signal intensity, very uniform. And here.

10:38

Then you've got this kind of bulbous concentric areas

10:42

of thickening with intermediate signal intensity

10:45

to high signal intensity on the short, uh, te

10:48

or the T one weighted images.

10:50

In some cases, you're going

10:51

to see high signal intensity in these fibromas

10:54

and even enhancement.

10:56

There's been reports in the literature that toxic,

11:00

that show this high signal intensity

11:02

and enhancement in the fluid sensitive sequence.

11:05

So don't let that throw you off.

11:07

Plantar fibromas can have that appearance, uh,

11:10

and it's important for you to report that.