0:33

All right, well thank you so much for the introduction and, uh,

0:37

we'll go ahead and get started. Alright,

0:41

so I am using a, um, I'm a, I'm, I'm at Home Workstation. I'm using a,

0:46

a free software called ros. It's kind of like Cyrex, which I used to use, but,

0:50

uh, Cyrex isn't free anymore. So this one seems to work pretty well,

0:55

but I'm not gonna be getting too fancy with the packs. Um,

0:59

so this first study I'm gonna share with you, um,

1:02

I'm gonna share with you kind of the same way I, uh,

1:04

go over cases with my fellows, um,

1:07

which is what I really enjoy doing is going over these cases at the,

1:10

at the workstation. Um, so this first case is a,

1:14

it's a beautiful knee, m r i. This is a young man, uh,

1:18

who had a history of knee pain after an injury.

1:22

The clinicians suspect he had some ligament injury.

1:26

The original injury was sustained while doing a pole vault about, uh,

1:30

three weeks ago. So when approaching the knee,

1:35

I, uh, I really like to start off by looking at the bone and joints first,

1:39

looking at the marrow signal, the presence of effusions,

1:42

these kind of things to get a, an idea of the big picture. So,

1:47

scrolling through here, you know, right away we get the, uh, we see this,

1:52

uh, very characteristic pivot shift type bone marrow contusion

1:57

pattern. Um, and what we see here,

2:00

this is what I actually call an osteochondral fracture at the condyle patella

2:05

sulcus of the lateral femoral condyle.

2:07

And I call it that you can actually see a little area of interruption of the sub

2:10

chondral bone plate there in addition to the extensive regional marrow edema.

2:15

And then there's the corresponding, uh,

2:18

contusion of the posterolateral aspect of the tibial plateau.

2:23

I also like to scrutinize this area here 'cause sometimes you'll actually see a

2:26

fair amount of depression back there,

2:28

more of a fracture than just marrow contusion.

2:31

And that's something that I like to communicate to the orthopedic surgeons when

2:35

I see that. So of course, in the pivot shift mechanism,

2:39

the pivot refers to the valgus stress, which causes the, um,

2:42

tension on the medial supporting structures of the knee shift is that anterior

2:47

translation of the tibia With respect to the femur leading to these impaction

2:51

injuries here, a lot of times during the, during this, um,

2:56

process of injury, there will be sort of a co counter coup injury, uh,

3:00

at the medial aspect of the tibial plateau, the poster medial aspect.

3:04

We do see a little bit of that here.

3:06

There's also contusion at the medial femoral condyle.

3:09

We'll look at that a little bit more in a second.

3:11

A little bit of an unusual pattern there. Um, always look at the fibrillary syl.

3:16

I don't see any contusion there in this particular case.

3:20

Uh, next up I look at the ligaments. So this is not a, uh,

3:25

diagnostic dilemma.

3:26

Here we see disruption of the central fibers of the medial of the anterior

3:31

cruciate ligament, abnormal lax morphology of the A C l.

3:37

And I always like to,

3:38

especially when I'm going over with the trainees to look at the a c l in all

3:42

three, three planes.

3:43

And here you really see that interruption in the mid portion there. Uh,

3:47

also some tearing at the, at the origin and the notch

3:52

and always like to look at it on the axial view as well.

3:55

There's some tearing proximally here. And, uh,

3:58

just some disruption in the mid portion

4:02

when we're talking about anterior translation. Um, by convention, we,

4:07

we evaluate that at the mid portion of the, uh,

4:10

lateral part of the tibial plateau.

4:12

And we do see some anterior translation of the tibial with respect to the femur,

4:17

kind of the M r i equivalent of the drawer sign,

4:21

the posterior cruciate ligament we see here is intact.

4:26

Then move on to the medial supporting structures and we can see that there's

4:30

definitely some problems with the medial supporting structures of the knee.

4:33

In terms of the superficial part of the M C L, you can see it's quite thickened.

4:38

It's got abnormal signal and morphology and there there are some areas of,

4:43

uh, attenuation and tearing there. This is like a type two injury,

4:47

I would say. As far as the deep portion of the, uh,

4:50

of the medial collateral ligament,

4:52

we nicely see here the deep meniscal tibial ligament. However,

4:56

the meniscal femoral ligament, uh, is disrupted. We don't see it.

5:00

There may even be a little sliver of bone separated here.

5:04

The radiograph would show you a little avulsion fracture there and that's

5:07

probably why we have this extensive contusion pattern at the medial femoral

5:11

condyle. Moving over to the lateral supporting structures.

5:17

So we can come anteriorly.

5:18

We've got the ileal tibial band inserting at gertie's tubercle

5:23

more posteriorly. We'll see the, uh,

5:26

lateral collateral ligament and sometimes when you have a lot of anterior

5:30

translation of the tibia, you'll actually be able to see the,

5:33

the lateral or fibular collateral ligament all on one slice,

5:36

which is a abnormal finding. It's intact distally,

5:40

but you do see that abnormal signal and thickening proximally.

5:42

So there is some sprain of the proximal aspect of the lateral collateral

5:46

ligament and the biceps femoris tendon looks, looks alright

5:58

as far as the extensor mechanism, the quadriceps and patellar tendons,

6:02

they look pretty reasonable in terms of effusion.

6:07

There's a pretty moderate sized effusion and we see a little bit of thickening

6:10

of that medial pica. Moving on to

6:17

the menisci,

6:18

you can see that there's some major problems with the posterior horn of the

6:22

lateral meniscus. Uh, really a complex tear there.

6:25

And there's also some injury of the posterior lateral joint capsule there.

6:29

I don't see a normal appearance of the popliteal meniscal sles

6:35

and, um, we can look at it on the coronal view as well.

6:41

Here we really nicely see a radial tear.

6:43

This is actually in the anterior horn of the lateral meniscus. Um,

6:49

and I actually like to look for radial tears. Also on the axial images,

6:54

we don't always get the right slice, but sometimes we do get a little fortunate.

6:57

And here you can really nicely see that radial tear of the anterior horn.

7:06

And we can also see posterior horn tear, which is,

7:11

it's pretty complex.

7:15

The medial meniscus

7:20

looks pretty good.

7:25

And, um, I won't be mentioning maybe every single normal finding on every case,

7:30

but, uh,

7:31

I don't see any obvious other than this area of osteochondral injury here,

7:35

any other areas of, uh, significant chondral abnormality.

7:41

So that's my approach to sort of a routine anterior cruciate ligament

7:46

tear case. Um, let's go ahead and pull up that, uh,

7:51

first multiple choice question. So,

7:56

deep notch sign corresponds to injury of what structure?

8:02

Yeah, lateral femoral condyle. Very good. Alright,

8:06

so we're move on to our second case. Alright,

8:10

second case. This is, um, another young person who had,

8:15

has right knee pain for two days after a fall.

8:18

And we're also evaluating for internal derangement.

8:24

So again, we're looking through the, uh,

8:26

starting off by looking at the marrow signal for contusions.

8:29

I do see a little contusion here at the, um, medial aspect of the patella.

8:36

Otherwise, bone marrow signal looks pretty reasonable.

8:40

There is a small, small to moderate joint effusion,

8:44

and here we see that area of contusion again.

8:47

Now this is kind of an interesting case in that when I see contusion at this

8:50

part of the patella, um,

8:52

I usually think of a lateral patella dislocation that usually comes along with

8:57

a, um, corresponding con, uh,

8:59

contusion or fracture at the lateral aspect of the, uh, femoral condyle,

9:03

which I don't see at all in this case.

9:05

So sometimes you can see in the case of a lateral dislocation,

9:09

isolated contusion of the patella. Um,

9:12

alternatively this could have been just a direct area of,

9:15

of trauma or direct area of impact.

9:18

There does seem to be a low grade or partial injury of the reticulum at its

9:23

patella attachment.

9:28

So let's, uh, go ahead and move on to the ligaments.

9:34

So in this case, we do have a nice intact, a c l. So you can see this,

9:39

um, an medial bundle of the, an anterior cruciate ligament, uh,

9:43

nicely paralleling that bloom and sat line. Normal orientation of the fibers,

9:48

posterior cruciate ligament also looks good.

9:50

We see a little ligament of humphrey there.

9:56

Moving on to the medial supporting structures of the knee.

9:59

We do see a little bit of a problem here.

10:01

Now the superficial fibers of the M C L are intact,

10:05

but there is a little bit of edema, superficial and a deep to the M C L.

10:09

So that's characteristic of a low grade sprain. Uh,

10:12

it is a little thickened as well. And again,

10:15

i I don't see a normal appearance of the deep meniscal femoral component.

10:20

So I, I do suspect that there's a tear of that deep portion of the M C L.

10:28

And so as far as the medial supporting structures of the knee,

10:30

we have a injury of the superficial portion of, of the M C L,

10:34

the deep portion of the M C L, the medial reticulum.

10:38

And there is another structure of the, uh, um,

10:42

of the medial supporting structures actually in the,

10:45

the posterior medial corner of the knee that I wanna highlight here.

10:48

And that's what's called the posterior oblique ligament.

10:51

That's part of the posterior medial corner,

10:53

which is an area we don't talk about too much.

10:55

We do see it is a little bit thickened and wavy back here.

10:58

This is the posterior oblique ligament. There is a fluid around it. So this,

11:03

this is consistent with a posterior medial corner injury.

11:07

The structures that make up the posterior medial corner of the knee, uh,

11:10

those supports. You got the posterior oblique ligament,

11:13

the oblique popliteal ligament, which is more central. The, uh,

11:17

semimembranosus tendon, which is this very broad insertion here, you know,

11:22

we got our medial head of the gastroc anemia tendon here,

11:25

the semimembranosus tendon here. And of course this, uh,

11:30

fluid, uh, outpouching, there is a, is a baker cyst or a popliteal cyst.

11:34

By definition it extends between these two structures.

11:38

Looks like it's leaking fluid inferiorly by the way.

11:41

Semi menos does have some abnormal signal in it, some tendinosis,

11:45

probably other structures. The, um,

11:48

that support the poster medial corner or the poster poster medial joint

11:52

capsule itself and the posterior horn of the medial meniscus.

11:57

Here again, we see some of that edema about the, uh,

11:59

superficial aspect of the M C L.

12:06

So going back to our ligamentous review it band looks okay,

12:11

co later collateral ligament is intact. Biceps,

12:15

femoral tendon looks okay. Um, so no problems there.

12:23

Extensor mechanism, there is a little bit of tendinosis of the quadriceps.

12:27

Tendon insertion is probably a little zaphy there,

12:30

which we would see better on radiographs, a patellar tendon looks okay,

12:42

So pretty straightforward case there. Um,

12:46

let's go ahead and, um, take a look at the menisci first before I, uh,

12:51

before I move on. Lateral meniscus looks pretty good.

12:54

What about the medial meniscus?

12:58

So we've also got an injury of the, uh, we got a lot of edema around this area.

13:02

We've got injury of the posterior oblique ligament and we also have a injury of

13:06

the posterior horn of the medial meniscus.

13:08

Overall pattern here is somewhat complex,

13:10

but predominantly a longitudinal horizontal type pattern.

13:14

It does extend to the undersurface or the, uh, inferior meniscal surface.

13:19

Can look at it on the coronal view,

13:21

you see actually extends into that posterior root ligament.

13:24

So that is another thing we wanna mention in the report when we, uh,

13:28

discuss this particular tear. Uh,

13:30

when the posterior posterior root ligament completely tears,

13:34

it's a bad prognosis for, for that compartment of the knee.

13:37

There's not really a whole lot that can be done at that point. For now,

13:40

the cartilage looks pretty good in this compartment.

13:46

Alright, let's go ahead and pull up the, uh,

13:49

multiple choice question for this case.

13:54

Alright, let's see. Let's see what we got. Yeah, so all these are, uh,

13:59

structures you mentioned. Uh, posterior oblique ligament. There was some, uh,

14:02

injury there. Oblique popliteal ligament. Another, another one,

14:06

semimembranosus tendon. We noticed some thickening,

14:09

some tendon otic changes there.

14:10

Poster medial joint capsule is another component in addition to the posterior

14:15

horn of the medial meniscus. Alright,

14:21

alright, here's our next case.

14:24

This is a middle aged female patient. Um,

14:28

this was referred to us, um, by a foot surgeon,

14:33

an orthopedic, uh, foot expert. And he's concerned about, uh,

14:37

adult acquired flat foot that this patient had, uh, uh, had presented with.

14:44

So what I'd like to do is, um,

14:47

go over the approach to the patient with adult flatfoot deformity. Um,

14:52

there's kind of a checklist approach that I like to take to make sure I mention

14:55

all the relevant findings.

14:56

'cause there's often quite a bit going on with these patients. Of course,

14:59

we like to start off with radiographs. Um, we can see the findings of, uh,

15:04

midfoot sag and pest planus, uh, talo navicular uncovered these kind of,

15:09

uh, radiographic findings. And then we move on to the Mr M R I.

15:13

And so let's talk about the, again, I always start with the bone and joints,

15:17

and that includes, uh, signal alignment, uh, effusions, all of that.

15:21

There is a small ankle effusion. Um,

15:24

there is no obvious bone contusion stress fracture and this age GR group always

15:29

wanna watch out for things like calcaneal stress fractures. Um,

15:32

there are some degenerative changes of the midfoot, but nothing, uh,

15:36

too impressive when we look at the,

15:41

a short axis view. Look at this, uh, orientation here.

15:45

So usually the navicular is gonna cover the entire articular

15:50

surface of the alis but here we have quite a bit of what we would call tail

15:54

navicular coverage. And that's, um, characteristic of hindfoot valgus,

15:59

which is something that happens with, um,

16:02

collapse of the medial longitudinal arch. So they've got that.

16:06

How do we tell if there's a, um,

16:11

hindfoot valgus on, um, non-weight-bearing MR images? Well,

16:15

it tends to be a little bit, a little bit under, uh,

16:20

demonstrated on these non-weight-bearing images.

16:21

But what I've gathered from the literature is the best way to look at that is

16:26

you look at the, the most posterior image on the coronals,

16:30

that includes a little bit of the distal tibia as well as the

16:34

medial border of the calcaneus.

16:37

And you draw an angle between the long axis of the tibia and this,

16:40

this medial border, the calcaneus,

16:43

it really should be less than 10 degrees in a normal patient.

16:45

And we can just see here that there is some, some angulation there.

16:49

So this is a patient that has pest planus with hind foot valgus.

16:54

We talked about the bones and joints. Let's go onto the tendons. Of course,

16:58

the tendon that we're gonna really focus on is the posterior tibial tendon.

17:01

That's the most important dynamic stabilizer of the medial longitudinal arch of

17:06

the foot. And just from the first slice we already see we've got some problems.

17:10

Here's the posterior tibial tendon. Here's the flexor lysis,

17:13

longest tendon right next to it. In terms of size,

17:17

the posterior tibial tendon should be about twice as big as the F H L in

17:22

short axis. Um, no more than that.

17:25

And here you see it's quite a bit larger than that.

17:26

We see some abnormal signal in there, tendinosis.

17:29

There's some teno synovitis and abnormal amount of fluid around it.

17:34

We follow this down, we see some kind of low level interstitial tears,

17:38

and then we see a complete tear.

17:40

We see a fluid gap there at the level of the medial malleolus.

17:43

This is a common area of failure for this tendon.

17:46

It's a relative watershed zone for the posterior tibial tendon and also an area

17:50

of mechanical irritation.

17:55

Here we see just a string of it. We see some torn fibers here.

18:00

Here's kind of a bunched up, uh, torn component of it distally.

18:04

And as you know, it inserts onto the, um,

18:07

navicular and you see kind of a very tendon otic, uh,

18:10

torn distal aspect of the P t T. So this p t t's totally out. Uh,

18:15

it's a high grade tear, uh, type one or grade one tears. It's, uh,

18:20

tendinosis with maybe some low grade interstitial tears. Type two,

18:23

it's a attenuated there's.

18:25

And type three is basically a complete or nearly complete tear

18:30

flexor haliss, longest tendon doesn't look too bad

18:35

or I, I'm sorry, the flexor digitorum tendon is what I meant to say earlier.

18:40

Doesn't look too bad. Uh,

18:42

flexor haliss longest tendon is a pretty normal appearance.

18:47

Moving on to the peroneal tendons, I think they're very passable.

18:52

Uh,

18:53

I don't like to really scrutinize and overcall peroneous bre brevis interstitial

18:57

split tears. The anterior extensor tendons look. Okay,

19:01

and the achilles tendon, it's got some mild tendonosis, uh,

19:05

which we can see here. But, uh, not too bad.

19:10

Alright, moving on to the ligamentous structures.

19:12

We've got intact syndesmotic ligaments,

19:18

posterior talo fal ligament looks okay, kind of an irregular,

19:22

slightly thickened looking, uh, A T F L.

19:25

This calcan fibular ligament is very thick.

19:28

You can see how how well seen it is usually you really have to look for it.

19:32

And then this is, this one is quite thick, uh, very low signal.

19:35

So this patient's had some sprain before

19:40

still on the ligament. I like to look at the deltoid ligament,

19:43

which does show some degenerative type signal. It's not totally normal.

19:49

Here's a thickened spring uh, ligament right here.

19:53

Here's your torn P t T fibers in there. And superficial to that,

19:57

we see this bode flexor reticulum. So on this view, you,

20:02

it's a really a layered structure that supports the medial part of the ankle.

20:06

It'll see deep deltoid, ligament fibers.

20:11

Superficial to that. You'll see the, uh, fibers like the tibial spring,

20:15

the superficial parts of the deltoid ligament. Then you have gliding of the, uh,

20:20

p t t in between those structures. And then you've got your, um,

20:24

flexor reticulum superficial to all of that. And, uh,

20:29

normally if, if it's a really healthy ankle,

20:31

you can see fat planes between all these structures. Here we look at this T one,

20:35

it's just all very fibrotic glob.

20:38

So very hard to distinguish what's going on there.

20:40

It's consistent with that injury there. Um,

20:44

I mentioned before kind of a checklist approach to these cases. Um,

20:48

there are a lot of secondary findings of posterior tibial tendon dysfunction

20:53

and, uh, and, um, adult, um,

20:56

flatfoot deformity that we should look at that are relevant to staging and kind

21:00

of determining for the surgeons whether they need to do just kind of

21:03

conservative therapy,

21:04

whether they need to do a P T T reconstruction or

21:09

interweave, um,

21:11

or whether they have to do something like a triple hind foot arthrodesis, um,

21:15

or maybe just a, uh, a medial calca osteotomy.

21:20

So things we talk about, you know, is there spring ligament failure?

21:23

That's an important thing to look for. And in this case,

21:26

the spring ligament is just very thick.

21:28

So when we talk about the spring ligament,

21:30

the most important portion of it is the s medial band,

21:33

which is the one we see here.

21:34

So this is very thick and it's kind of like holding onto this, um,

21:39

Taylor head for dear life.

21:40

It's the only thing really controlling this thing from slu from falling out into

21:44

valgus. So it's acting as a restraint there, but it's still holding on. Um,

21:50

here are the other parts of the spring ligament. There's the, uh,

21:53

medial plantar bleak band and the, uh,

21:56

infra plantar longitudinal band here. But those are a much less, uh,

21:59

functional importance. Something else we look for. Talo navicular mal alignment,

22:04

which this patient does have. We mentioned, uh, lateral,

22:08

hind foot impingement is something else we look for. You know,

22:10

I talked about that measurement that we can make back here. Uh,

22:14

when the patients fall off into valgus enough,

22:16

you'll end up having some impaction between the, um,

22:20

palus and the calcaneus with some remodeling back here, some edema.

22:25

That's something you'll see eventually.

22:26

Then eventually you'll have sub fibular impingement where the fibula even comes

22:30

down and contacts with the, uh, the calcaneus and causes some remodeling there.

22:35

So that's a more advanced case. Deltoid ligament failure is a problem as well.

22:41

Kind of an indication for, uh, hindfoot fusion. Um,

22:45

not a normal looking deltoid ligament here by any means, but it's not disrupted.

22:50

Sinus tarci syndrome is something that also comes from these abnormal

22:54

biomechanics, sinus tarci here, it's got some edema in it. How about the fat?

22:59

You should just see fat and ligaments in that area.

23:01

There's a fair amount of fibrosis in there.

23:03

So they could certainly have some symptoms of sinus tarsi syndrome. Um,

23:08

the plantar fascist,

23:09

an important static stabilizer of the foot and tends to be affected here.

23:14

I like to look at it on the short axis here,

23:17

and it is a bit thickened.

23:21

You've got some, um, plantar fascia thickening, no doubt about it.

23:25

Maybe a little fibromatosis here. And oa,

23:28

secondary OA is another thing we'll see.

23:30

So that's kind of my approach to a patient with a posterior tibial tendon

23:34

dysfunction, in this case a high grade tear and a hind foot valgus.

23:39

Let's go ahead and pull up, uh, multiple choice question three.

23:45

Alright, so everyone got that posterior tibial tendon.

23:47

The primary dynamic stabilizer, the F H L and the perineal longest are,

23:52

um, have a more complimentary role.

23:57

The deltoid ligament is a static stabilizer. So gimme a sec here,

24:00

I'll pull up the next case. Alright,

24:05

so kind of on a similar theme to some of the cases we showed earlier,

24:08

this is another internal derangement case.

24:11

This was a teenager who suffered a knee injury while playing football. Um,

24:16

this is of course something that we're seeing more and more of as, uh,

24:20

the intensity of youth sports, um,

24:22

becomes more and more and we get an increased amount of imaging.

24:27

So they're worried about internal derangement.

24:29

And I believe so this patient got a radiograph at a urgent care somewhere,

24:33

and they, they did detect a sagon fracture so their, their, uh,

24:38

suspicion was high.

24:39

A sagon fracture is something that we might overlook on Mr if we don't look at

24:43

the radiographs or we don't have access to them. Of course,

24:46

if you do teleradiology, um,

24:48

you may only be given the MR with no radiographs to compare to. But, um,

24:54

uh, that, that is the complimentary nature of radiographs or in a good history.

24:58

So again, let's start off with, uh, the marrow. So again,

25:03

we see that characteristic marrow contusion pattern of a pivot shift type

25:08

injury. This patient's got additional areas of contusion as well.

25:12

So we've got edema within the fibular syl, which of course makes us think about,

25:17

you know, could there be a posterolateral corner injury component to this.

25:22

This patient has edema at the inferior pole of the patella,

25:26

which is kind of a unique pattern in the setting of a c l injury.

25:30

There is something called a patello tibial injury.

25:33

And it's thought that when the patient's quadriceps contracts strongly at the

25:37

time that the A C L is tearing the, uh,

25:40

the patella will come down and impact on the anterior tibia.

25:44

And that's what causes that contusion pattern there.

25:47

And then we also have kind of that conico type pattern post medial aspect of

25:52

the, uh, tibial plateau and also medial femoral condyle again.

25:57

Alright, in terms of, uh, ligaments, of course, this is not a dilemma.

26:01

We see a complete disruption of the, uh,

26:04

anterior cruciate ligament at its mid portion, very wavy, disorganized fibers.

26:09

Posterior cruciate ligament is intact

26:16

in terms of the ligaments. Let's look at the, uh, medial supporting structures.

26:19

So the superficial portion of the M C L is intact. It attaches way down here.

26:24

Um, there is some edema around it, and again,

26:27

we're seeing disruption of the deep meniscal femoral component.

26:31

So this is something I didn't used to always look for right away,

26:33

but the more you look for it, the more you will find that.

26:36

And sometimes you will see a little avulsion fracture, uh,

26:40

where you would would have expected it to attach

26:45

the, uh, deep meniscal tibial ligament. Looks like it's, uh, it's okay there.

26:50

Moving on to the lateral supporting structures,

26:55

again, we have some proximal sprain of the lateral collateral ligament.

27:00

Here's our IT band and there is that sigon fracture.

27:04

So I don't have the radiographic correlate for you,

27:06

but you can see this interruption in the cortex right there. Now,

27:10

there has been for a long time debate about what structure actually attaches to

27:15

the sigon fragment and, and pulls it off. Um,

27:18

there is a nice paper that I think is worth taking a look at is by, um,

27:22

came from U C S D from Flores, uh, etal 2016.

27:27

It was in, I believe,

27:28

skeletal radiology where they looked at a large series of sigon fractures and,

27:32

and talked about which structures attached to them. Um,

27:36

the majority of them were the, uh,

27:38

what's called the anterolateral ligament or the mid third lateral capsule. Um,

27:43

there was a minority of them that were attached to the posterior fibers of the

27:47

IT band.

27:48

And there were also some that were attached to both kind of in an overlap area

27:53

and there was no other structures that attached to the sigon fragment.

27:57

So in this case,

27:58

here's our IT band and it looks like the posterior most fibers

28:03

of the IT band are attached to this fragment.

28:05

But also this is your ant lateral ligament here, also attached to the fragment.

28:10

So this is kind of one of those where it's in the overlap of both.

28:16

If we look at our axials, here's the fragment right there,

28:20

this large structure curvilinear structure here. Here's your IT band.

28:25

So kind of the very posterior fibers of it are grabbing onto that fragment.

28:29

And here's your mid third lateral capsule or anterolateral ligament also

28:32

attaching to it. So that's your sigon fragment.

28:41

You biceps tend biceps, femoral tendon looks. Okay, um,

28:46

there's a, um, popliteal, fibular ligament back here.

28:50

Let's take a look at it on the, um, sagittals.

28:55

So there is a slightly slightly wavy appearance of a popliteal

28:59

fibular ligament back here, but it's not completely disrupted. Um,

29:03

but this worth mentioning and, uh,

29:05

palate's muscle itself just has a very small amount of edema in it.

29:09

So if at all, it's not a very, uh,

29:11

not a lot of injury of the poster lateral corner in this case.

29:15

Moving on to the menisci.

29:18

So the medial meniscus has extensive tearing and this is kind of a variant of

29:22

what's what's been, uh, called a ramp lesion. Um,

29:26

it's called a ramp because basically the,

29:28

the horn of the meniscus is shaped like a ramp, um,

29:31

when the anterior cruciate ligament is disrupted,

29:34

this posterior horn of the medial meniscus is a,

29:36

is a limiting structure pre preventing anterior translation of the tibia with

29:41

respect to the femur. And as a result it becomes torn. Historically,

29:45

we think that these have a very good potential to heal,

29:48

but they've been repaired more and more because it's thought that if this is not

29:52

repaired, it's gonna continue to be very lax and not serve as a restraint.

29:56

The tear can progress and it can contribute to failure of an anterior cruciate

30:01

ligament graft if we don't restore this restraint. So very kind of a complex,

30:05

but predominantly, um, a longitudinal vertical tear back there.

30:12

Uh, we can look at it in this plane here.

30:17

Lemme see it, see it there kind of a complex tear. It's got, uh,

30:21

horizontal and vertical components to it.

30:33

The, uh,

30:35

lateral meniscus also has some tearing at the posterior horn. Um,

30:40

there is a classic tear known as the wrist berg rip where the, uh,

30:44

ligament of, uh, wrist berg, uh,

30:48

which is posterior to the uh,

30:50

P C L comes across is this structure here.

30:54

And usually blends imperceptively with the posterior horn of the, uh,

30:59

lateral meniscus. But it, it can be torn off in the case of an A C l injury.

31:02

But this doesn't look like a classic case of that. It's more the, uh, the, uh,

31:07

uh, dis the lower surface of the, uh, uh,

31:11

posterior horn that's torn here.

31:20

Okay. The effusion is large and, uh, those are, those are really the, uh,

31:24

the primary findings on this case.

31:26

So just breaking down another sort of a complex a c L type injury.

31:31

Here's a, a normal structure that we see in the, the, uh,

31:34

young adolescent knee, this posterior white stripe. This is just a,

31:39

a vascularized tissue there. It's doesn't represent, um,

31:44

a avulsion of the periosteum or anything like that.

31:49

Let's, uh, go ahead and pull up multiple choice question number four.

31:54

So sigon fracture may be attached to which structure or structures.

32:01

Okay, great. You all got this one. All right, I'm gonna pull up the next case.

32:08

All. So this case,

32:11

this was a young patient who suffered an acute leg injury

32:16

and, uh, they were worried about potentially, uh,

32:18

either a calf muscle injury or an Achilles tendon tear.

32:23

Um, I think this is a good indication for ultrasound or m r i.

32:28

Um, they went ahead and got an M R I and let's go ahead and take a look here.

32:33

I'll tell you the, uh, the findings are not in the bones here. We're gonna, uh,

32:36

really scrutinize the soft tissues here.

32:40

So this is a beautiful case. What we see here

32:44

is a large hematoma between these two muscles.

32:48

You've got the medial head of the gastro anus,

32:51

and deep to that you've got the sous.

32:53

So if you've got all these blood products here, and then there is, uh,

32:56

more of like a organizing clot or hematoma here.

33:04

If we follow the, uh, muscle down, you can see an area here.

33:09

The, the, um, the medial head of the gastrocs has an end,

33:13

has a deep fascia,

33:15

which is usually opposed to the more posterior fascia of the underlying soleus.

33:20

You can see it as this thick black line. And you see an interruption here.

33:23

So this is a, a vertical fascial tear, um,

33:27

of the medial head of the gastroc anus associated with the tear of the muscle

33:31

itself. You see that feathery edema going, going throughout the muscle,

33:35

as well as some distortion of the cul muscular architecture,

33:38

kind of a moderate grade muscle tear and a fascial tear.

33:43

So this is what we, uh, historically call a tennis leg. It's, it's a, uh,

33:48

myofascial tear of the medial head of the gastroc anemia.

33:51

And the classic finding is this big hematoma between the two muscles. Uh,

33:56

this is something that we can see nicely on ultrasound. Um,

34:00

sometimes they will present with a presentation that's similar to, uh,

34:05

an Achilles tendon. They'll hear a pop, they'll grab their, uh, their ankle.

34:09

Here you can see however, the achilles tendon is intact,

34:14

but as you can see, the blood is trickling down towards the ankle. I mean,

34:18

I saw a patient with this same injury some months ago and they had a lot of,

34:23

uh, ecchymosis around the ankle where this blood kind of extends down to.

34:27

So the presentation can really resemble an Achilles tendon tear. But, um,

34:32

if you had to choose between the two injuries, this is,

34:35

has a much more favorable recovery, even though it's extremely painful. Um,

34:40

these will tend to heal better, whereas a, a complete achilles tendon, um,

34:44

typically requires surgical reconstruction and a more prolonged, um,

34:48

immobilization. Um,

34:51

there is a good rad source article where they talk about this kind of injury and

34:56

the different shapes of the tears. This is kind of the vertical component.

35:00

You see this kind of gap between the, uh,

35:03

the areas of intact fascia. If you follow down,

35:05

eventually you get to an area where you don't see any fascia and that's

35:09

considered the, the more transverse part of the tear.

35:11

Some of these have more of like an L-shaped tear and the hematoma will just kind

35:16

of fill in the space where the, uh, where the, um, fascia is disrupted.

35:21

Uh, historically people talked about, uh,

35:24

a plantars tendon tear causing this. Um,

35:29

but it's really just the, the torn muscle and fascia,

35:31

which causes all this bleeding. Um,

35:35

we can see the plantars tendon coming across

35:40

here. We can kind of pick it up in certain parts.

35:43

Here it is down further down and it kind of blends in with the achilles tendon,

35:49

follow it up. And some parts it'll just sort of blend in with the fascia.

35:52

It's really a kind of glued to the fascia of the sous,

35:57

kind of pick it up there. And then there's that muscle right behind the, um,

36:02

the neurovascular bundle. So, nice example of a tennis leg.

36:07

You know, you see this injury, you can make this call. Um, let me show you. Um,

36:15

Here on the sagittal, you see the, the muscle belly will be lifted up.

36:19

It's usually kind of basically glued down to the sous.

36:22

You see some torn muscle fibers down there. There's that clot,

36:25

there's that feathery appearance of a muscle tear. And uh, yeah, really nice,

36:29

nice example. I think this is a multiple choice.

36:34

Question number six goes along with this one.

36:40

Alright, very good. Go,

36:44

go ahead and get my next case. Alright,

36:49

let's change it up a little bit and take a look at an elbow.

36:57

So, very common indication here. They're concerned about a biceps tendon,

37:02

a recent biceps tendon tear. We can definitely help them with that. Um,

37:07

this case, I do not have the fabs view. Um,

37:12

sometimes we get that, sometimes we don't.

37:15

I think we can see the distal biceps tendon well with their usual planes, um,

37:19

may not necessarily be worth, um, you know,

37:22

re localizing the patient and getting that view. But I personally like it.

37:26

I'm in an academic institution. I, I don't, I don't mind the, uh,

37:29

the extra scanner time to get these nice images. I figure if, if, uh,

37:33

if we don't use it then um,

37:35

probably one of the neuro guys will use all the scanner time. So,

37:38

so I like to get all the sequences I can, but let's see what we can see here.

37:43

So this one is not a diagnostic dilemma in terms of whether or not

37:48

the biceps tendon is torn, but I think it, it, uh,

37:51

is a good example for looking at the anatomy.

37:54

And there are a couple surprises in this case as well, you know,

37:56

so we don't have that satisfaction of search. So here's our biceps tendon.

38:01

Um, approximately,

38:04

Take one second here.

38:07

So as we follow it down,

38:08

we can actually see that there's actually two biceps tendons here.

38:12

So of course there is a long head and a short head of the biceps tendon.

38:17

The long head comes from the supra glenoid tubercle.

38:20

The short head comes from the oid process along a lot of the length of the

38:24

biceps tendon.

38:25

These two are really intertwined and kind of form a single biceps tendon,

38:29

but most patients to some extent distally, they'll have two distinct,

38:35

um, two distinct tendons macroscopically, um,

38:40

as opposed to sort of one single tendon inserting on the radial tuberosity.

38:45

So this is a good example here.

38:47

So we can see this part of the tendon is really quite torn.

38:51

You see very regular, there's fluid around it.

38:55

And then basically a complete gap here.

38:57

So we've got a stump there and then we come down to the radial tuberosity.

39:03

Um, and that part does not attach there,

39:08

but if we go more proximally, you see this part here,

39:12

you can follow that down, this kind of more diminutive head.

39:15

This one is actually intact.

39:16

It comes all the way down and attaches to the radial tuberosity.

39:20

So if you wanna get a little extra style points,

39:23

we can mention which head of the biceps tendon is the one that's completely

39:28

torn or primarily involved.

39:32

Let's take a look at the coronal view.

39:36

I went ahead and flipped these ahead of time 'cause I don't know if some,

39:39

this is some of your experience, but they always come, uh,

39:41

flipped the wrong way when I get them.

39:45

Here's that intact portion that's coming down here.

39:47

We see that it attaching here and then here's nothing but fluid a gap here.

39:51

So most of it's missing,

39:53

and I'll tell you it's the short head that inserts more distally.

39:56

So the long head of the biceps tendon is running down here intact.

40:00

The short head is completely disrupted and is retracted. Um,

40:04

we measured something like 16 millimeters approximately. So, um,

40:09

we'll tell them that. One other detail that we can add is you see all this

40:15

edema, cosing medially here, kind of, um, enveloping these,

40:20

uh, ulnar

40:23

flexor muscles that in indicates that there's some injury of the, um,

40:28

lac ERUs fibrosis, which is a structure that kind of anchors the biceps tendon.

40:32

It extends in exact this, exactly this configuration.

40:36

So the edema along that course indicates some lacerte injury.

40:40

So that's something we can add to the report. Now, um,

40:45

we of course have to look at the rest of the study.

40:51

So really, um, when I look at the elbow,

40:53

I just break it down into sort of medial structures, lateral structures,

40:57

posterior structures and anterior structures, anterior structures,

41:01

really talking about the biceps tendon, which we talked about.

41:03

And brachialis tendon we see here inserting on the ulna,

41:08

maybe a little bit of tendinosis distally,

41:10

but it is intact and there's no bicipital radial bursitis, which is, uh,

41:14

kind of one of the um, uh, pathologies in this area.

41:18

There is a lot of fluid about that torn tendon,

41:20

but not what I would call a bicipital radial bursitis.

41:23

The posterior aspect of the elbow,

41:25

I'm really just talking about the triceps tendon and it doesn't really look

41:28

normal either. There's not much normal about this elbow.

41:32

There is some tendinosis and maybe a little bit of,

41:35

there's a little bit of edema.

41:36

It doesn't really look like an LEC bursitis there. All right,

41:40

so all the other structures, medially, we talk about the, uh,

41:43

ulnar collateral ligament looks pretty nice, the distal insertion there. Um,

41:50

your uh, common extensor tendon looks pretty good right there.

41:56

What about this common flexor tendon? Uh, not looking so good.

42:00

So we see some thickening. There's this actual fluid signal right there.

42:03

So this is like a moderate grade tear,

42:05

I would say kind of tennis elbow kind of a thing.

42:09

Radial collateral ligament kind of comes from this under shelf here and I just

42:13

see a lot of gray signal and irregularity there. So there's, there's some,

42:18

there's some chronic damage here. I see more of like a ligament there.

42:21

It's probably part of the lateral ulnar collateral ligament. Um, but these, uh,

42:26

medial supporting structures demonstrate some degeneration and partial tearing

42:29

as well. And um,

42:34

one thing we don't wanna forget to look at is the ulnar nerve.

42:41

And now keep in mind some proximal T two hyperintense signal in the ulnar nerve

42:45

is just something that we see. It's not very specific for nar neuritis,

42:49

but look, I look how big emus this ulnar nerve is, so it's quite bright.

42:55

So I would think about ulnar neuritis in this case.

42:59

Um, look at the T one.

43:04

You've got do have a little ancon epi petros there. Um,

43:08

that can put a little bit of pressure on the nerve.

43:11

There may or may not be why that nerve is bright,

43:14

but it is certainly worth mentioning the report. So I like this case.

43:17

It's got a few different findings. Um,

43:22

we have multiple choice. Question number five goes along with this case.

43:28

Alright, short head biceps inserts, distally, I've got a couple quick ones.

43:33

I'll just show you as kind of show and tells and then we'll take a couple couple

43:36

questions. This is just an interesting case.

43:39

This was a mi middle-aged male patient, um, came from an outside hospital.

43:43

I think these images are from an outside hospital. And yeah,

43:48

you see some susceptibility here.

43:49

This patient got biopsied somewhere and you can see probably

43:54

why the marrow signal is diffusely abnormal throughout the proximal hip.

44:03

We look closely though always gotta really look closely for that subc chondral

44:08

stress fracture.

44:09

I mean maybe that wasn't obvious when this was initially imaged.

44:12

Just the marrow signal changes can be quite subtle, but this is, uh,

44:16

what they would historically call transient osteoporosis of the hip.

44:20

I had seen a case recently that wasn't a pregnant or recently postpartum female,

44:24

which is a classic um, demographic, but um,

44:28

middle-aged males can also present with this. Um,

44:32

and just really exuberant marrow edema compared to this, uh,

44:37

somewhat subtle fracture line. But, um, important to recognize this pattern.

44:42

Uh, you know, the patient got biopsied unfortunately, but, uh,

44:45

we were able to make the diagnosis on this study here, um,

44:48

basically just a subc chondral fracture. So no, uh,

44:53

multiple choice question for this one. This was just kind of a show and tell.

45:00

Alright, this was a, uh, gentleman that, uh,

45:05

presented with anterior knee pain

45:11

and uh, this was kind of a unique case.

45:19

So he had pain particularly doing deadlifts at the gym. And,

45:24

um, this um,

45:28

kind of highlights the presence of an anatomic structure, which, um,

45:32

I learned about when I was a fellow,

45:33

which is what's called the pre patella quadriceps continuation.

45:38

So in basically in addition to the, um,

45:40

quadriceps tendon and the patella tendon, you've got, uh,

45:44

the structure that's the deepest tissue layer at the anterior aspect of the

45:48

patella. This is called the pre patella quadriceps continuation.

45:52

It is a, uh, continuation of the fibers of the, uh, quadriceps tendon,

45:57

particularly the rectus femoral tendon.

45:59

And it connects the quadriceps to the patella tendon.

46:03

It's been described as a chondro psal attachment and a injury can

46:07

occur at this site without distinct involvement of the patella or quadriceps

46:12

tendons and can be a cause of anterior knee pain.

46:14

So here's just a kind of a neat example. Kind of a isolated injury of the, uh,

46:19

pre patella, um, quadriceps continuation.

46:27

And here you have it little gap there. Uh, so you see a case like this,

46:31

you can give them a pre patellar quadriceps continuation injury.

46:37

Alright, so let's go ahead and take a look at some of your,

46:42

take a look at some of your questions. Okay, so those was, you know, um,

46:47

you know, I was going through these a little quickly so you know, I may have,

46:50

uh, you know, missed some of the things there. There's a question here.

46:54

What about the popliteal fibular ligament? So you may, may have, uh,

46:59

made an observation on one of these cases.

47:00

There was one where I mentioned that it looked a little wavy but not completely

47:04

torn. Um, I think if you get, um,

47:10

if you remember which, which number case that was,

47:13

I could probably go back to it. There's also a

47:16

Question. I think the first question was on the first case that you

47:18

Showed. First case, yeah. Okay, let's, let's go back to that one.

47:24

And, and it says question two asked for poster lateral structures,

47:27

the answer only poster medial structures. That was probably a mistake.

47:30

I was probably a typo on my part. Uh,

47:33

that case kind of illustrated the poster medial corner,

47:35

but I may have outta habit.

47:37

Talked about the posterior lateral corner because the poster medial corner never

47:41

gets, uh, the due respect. So in this case here we see the,

47:46

um, yeah, so here's a pope tendon coming across here.

47:54

I really don't see the papa patillo fibular ligament too well here.

47:57

So it may have been, may have potentially may be torn there.

48:00

Let's see if we can pick it up on this view.

48:10

A little bit tough. I have to say, this is one of I, for me,

48:12

this is one of the hardest things to, uh, to make a diagnosis of. Um,

48:17

I do see a lot of edema in the area where I would expect to see it. You know,

48:21

one of the things that kind of points me to look in the right area is that you

48:24

see these, um, ICT vessels coming through here.

48:27

That's kind of the area where I look, but, uh, I think it's a fair,

48:31

fair question, you know, to raise that. Um,

48:36

I do have the reports here. I don't think we call the

48:41

popliteal fibrillary ligament tear in this case, but, um,

48:46

but I would probably say it's not well seen.

48:51

Um, let's see. And then was there partial delamination of the patella plate?

48:57

This one did have some, um, uh,

49:02

some issues here. Let's see if I can find it.

49:12

Not too sure here,

49:20

but anyway, if any of y'all wanna unmute and ask me a question,

49:23

we can talk about it. But otherwise, you know, I hope this was, um,

49:28

useful for you all. Um, hope I had a few pearls in there.

49:32

It was my first time doing this, but, um,

49:35

I really enjoyed going through these cases. I think there's some, uh,

49:38

beautiful images and a lot to, uh, a lot to them. Thanks.