0:00

Okay, the first case was, uh, a 72-year-old male

0:04

with anterior pain and swelling.

0:06

Uh, we can start, I quickly start with the sagittal images.

0:09

The fluid sensitive, fat saturated sequences start

0:13

from the medial side.

0:14

Um, I evaluate based on,

0:17

we first look at the medial compartment,

0:19

then the lateral compartment,

0:20

then the pet femoral compartment

0:22

when we talk about the joint space.

0:24

Um, then I talk about the cruciate ligaments,

0:27

then I talk about the extensor mechanism,

0:29

then the posterior soft tissues, bone marrow,

0:33

and, uh, neurovascular bundle.

0:35

So you all can have your own approach.

0:37

There is, there was a template provided to you.

0:39

Um, you all can use that same template to, uh,

0:42

or you can do ligaments first, collateral ligaments,

0:46

cruciate ligaments, articular cartilage, whichever approach,

0:49

uh, you wanna take, you can take.

0:50

But I would recommend that have a systematic approach to,

0:53

um, interpreting, uh, scans.

0:55

And that's how your report should be,

0:57

should be very systematic under headings.

1:00

And then, uh, the conclusion should be a nice summary of,

1:04

uh, the first should be if, uh,

1:06

we should answer the clinical question.

1:08

Um, that should be the first point in the impression,

1:10

which should highlight what some,

1:12

the main diagnosis of the case.

1:14

And if there are, then, if there are any ancillary findings

1:16

that add to the diagnosis or add to the management and,

1:20

and other important ancillary findings.

1:22

So that's how the approach

1:23

and, uh, synthesizing the report should be.

1:26

So starting with the medial compartment, we'll start

1:28

with the medial meniscus.

1:30

So it's this, uh, hyperintense, uh,

1:32

structured fibrocartilage.

1:33

It should be dark on all pulse sequences.

1:36

And the periphery, it looks like a biconcave disc.

1:39

And as we go towards the center of the joint, it starts, uh,

1:43

uh, looking like two triangles in the front and the back.

1:46

So the parts of the meniscus are anterior horn body

1:48

and the posterior horn.

1:50

The minuscule tear will be any abnormal shape, size,

1:53

or signal intensity in the meniscus.

1:55

And we are talking about signal intensity.

1:58

We are talking about a hyperintense signal that extends

2:01

to the articular surface

2:02

of the meniscus on at least two consecutive images.

2:05

If it's only seen on one image, then the chances that of

2:09

that being a tear are not a hundred percent.

2:12

And the, it may or may not be a tear

2:15

and require a arthroscopic correlation.

2:17

And, but if it's just intrasubstance signal without

2:20

extending to the articular surface,

2:22

it's just intrasubstance degeneration.

2:23

So here the meniscus looks pretty good,

2:26

and we have to look all the way, uh,

2:28

to the intercondylar notch

2:30

to make sure we have covered all the way

2:31

to the root of the meniscus.

2:34

Then we look at the medial compartment, uh,

2:36

articular cartilage.

2:38

So cartilage is this great tissue, uh, a thin strip

2:41

of tissue that's you see overlying the cortex.

2:44

Um, so the cartilage abnormalities are graded based on outer

2:48

bridge classification, where, um,

2:50

grade one is superficial freeing.

2:52

Grade two is partial thickness cartilage loss, grade three,

2:54

full thickness cartilage loss.

2:56

And grade four is with sub chondral changes.

2:58

So here we can see some superficial frame, so some early,

3:03

uh, uh, grade one, uh, changes here.

3:07

And then, uh, we can look at the medial collateral ligament

3:11

that is better seen on coronal images.

3:13

We can finish off the sagittal images.

3:15

We, so this is your posterior cruciate ligament.

3:18

Looks intact. I'm going on my headphones, mate. Sorry.

3:21

That's all good. No apologies. Was there a question for me?

3:28

No apologies. Yeah, so then

3:33

recommend just if you can, uh, keep yourself muted

3:35

and unmute only, uh, when you have a question

3:37

or you wanna ask something, um,

3:40

then it's the anterior cruciate ligament.

3:42

It's intact. But as you can see that the, the signal

3:44

of the anterior cruciate ligament is not more confluent than

3:48

hypertense, like the posterior cruciate ligament.

3:51

And it's because the bundles

3:52

of the anterior cruciate ligament does not as compact

3:55

as the posterior cruciate.

3:56

Um, and actually, um, you can a lot

4:00

of times see there are two distinct bundles

4:02

of the anterior cruciate ligament, the intra medial

4:04

and the postal lateral bundle.

4:06

And sometimes you can see that bun two,

4:08

those two bundles separately.

4:10

And the brighter signal is from the fluid

4:13

or, uh, fluid in between the two bundles.

4:16

So the cruciate ligaments are looking okay, uh, coming

4:20

to the lateral side, the lateral meniscus,

4:22

lateral compartment, articular cartilage looks fine.

4:26

Now, evaluating the extensor mechanism, I think that's

4:28

where the abnormalities, this is the quadricep tendon

4:31

patella, then the particular tendon

4:33

and the tibial tuberosity.

4:34

So all these four structures

4:35

constitute the extensor mechanism.

4:38

Quadriceps tendon is showing normal signal intensity.

4:40

There's edema in the patella.

4:43

And the grossly abnormal structure is this ular tendon.

4:46

It's thickened proximally.

4:48

It has this abnormal signal, which is tendinosis,

4:51

and if it's fluid signal, we can call it

4:53

as an interstitial tear.

4:55

So this is proximal particular tendinosis, um,

4:58

which is also known as jumper's knee.

5:01

And along with it, what we see is, um, there's this fascia,

5:05

um, that is along the anterior aspect of the particular

5:08

that's formed by continuation of the quadricep tendon

5:11

and the particular tendon.

5:12

And there's destruction of the fascia.

5:14

So that's called delamination, uh, PrepU, uh, delamination.

5:20

And then moving on to the cor coronal images, uh, again,

5:24

we can look at the meniscus also on coronal images.

5:26

The anterior on body and the posterior hor looked okay.

5:31

Again, as we saw on the sagittal images,

5:33

there is the superficial cartilage fraying

5:35

in the medial compartment.

5:37

This is your superficial MCL.

5:39

Um, you can see arising from the, uh, medial femoral condyle

5:43

to six centimeters below the joint line.

5:45

So that's your superficial MCL lateral meniscus,

5:49

anterior horn body, and posterior horn.

5:53

Again, we have to evaluate all the way to the roots

5:56

of the menisci.

5:58

The articular cartilage looks okay.

6:00

Now, coming to the lateral collateral ligament,

6:02

which is not one ligament, it's a complex.

6:04

The most anterior part

6:05

of the lateral collateral ligament complex is this

6:08

iliotibial band, which inserts onto the Gord East

6:10

tubercle of tibia.

6:13

As you scroll more posteriorly,

6:17

this is your fibular collateral ligament.

6:19

It arises from the lateral femoral condyle and goes

6:23

and inserts onto the proximal fibula.

6:25

And right where there is the biceps tendon insertion,

6:28

so biceps tendon is more posteriorly.

6:30

So that's the biceps tendon.

6:32

Um, the fourth structure of the postal lateral complex is,

6:35

this is your popliteus muscle.

6:37

It forms the myotendinous junction,

6:39

and then you have the popliteus tendon,

6:41

which becomes intraarticular

6:43

and inserts onto the popal hetus along the

6:46

lateral femoral condyle.

6:47

So these are your, um, four important structures

6:50

of the lateral collateral ligament complex that we can, uh,

6:54

see on imaging all the time.

6:55

There are several other smaller structures

6:57

of the lateral collateral ligament complex, such

6:59

as aqua ligament, pleio, fibular ligament,

7:02

f fibular ligament,

7:03

but they're not always consistently seen on imaging.

7:07

Okay, so all that is, uh, looking good again, uh,

7:10

cruciate ligaments on coronal.

7:11

So you can see ACL is most ated,

7:14

but you can see it, uh, arising from the tibial eminence

7:18

and going and inserting onto the concavity

7:20

of the lateral femoral condyle.

7:23

So you have to, uh, make sure you see that attachment,

7:26

because a lot of times in acute ACL tears,

7:29

sometimes the sagittal image, uh, is not enough

7:32

to make a confident diagnosis

7:34

because there's a lot of edema along the ACL.

7:37

The fibers haven't retracted,

7:39

or if the, especially when they're torn from the femoral

7:42

attachment, uh, sometimes the only way

7:44

to tell is when you lose that attachment

7:46

of the ACL from its lateral femoral condyle on.

7:49

When we are looking, um, on coronal

7:51

and axial images, that's your posterior cruciate ligament

7:55

again, um, from the posterior tibial eminence

7:57

to the medial femoral condyle concavity in the

8:00

intercondylar notch.

8:02

Now moving on to axial images, uh, can start from

8:07

the proximal end.

8:08

Uh, looking at the, the quadriceps tendon looks okay,

8:14

Butler is showing edema.

8:15

This is the pre butler delamination of the fascia.

8:18

And as you come to the butler tendon, that focal tendonosis

8:22

and interstitial, uh, splitting of the tendon fibers, uh,

8:26

we also can assess the plo femoral, uh,

8:29

joint on the axial Monica.

8:33

So the putler should, uh, actually within the,

8:38

uh, clear groove.

8:40

So putler is, um, tracking centrally.

8:43

Now, the stabilizing ligaments

8:45

of the putler on the medial side are,

8:47

this is your medial of femoral ligament.

8:49

It starts from the medial pole of the ULA

8:52

and inserts onto, uh, the medial femoral ConEd,

8:56

right anterior to the insertion

8:58

or the origin of the MCL at the adductor tubercle.

9:01

So this is your MPFL, the medial petillo femoral ligament,

9:04

and at the same level on the lateral side

9:06

as the lateral ret macular.

9:08

So it could look at the integrity of those.

9:10

And there was a question that said if we

9:12

outline the joint capsule.

9:14

So this, all these structures from the joint capsule,

9:17

can you appreciate this joint capsule here?

9:20

And there is, and as we know these, the collateral ligaments

9:24

around the, uh, the, around the joint

9:27

or just condensations of the joint capsular structures.

9:32

So there are certain, uh, names, uh, given to the, the,

9:35

the condensations of the joint capsule.

9:37

So we're, this is at the level of the adductor tubercle,

9:41

the origin of the MCL.

9:42

You can see this post medial joint capsule.

9:45

This part of the post medial joint capsule is the, um, uh,

9:49

uh, tus, uh, the posterior oblique ligament, Paul.

9:53

And this part of the post median joint capsule is the

9:55

oblique paus ligament.

9:57

So any injury

9:58

to this will suggest post medial corner injury with ACL tears.

10:02

And similarly, at the same level, uh,

10:05

this is your post lateral joint capsule.

10:07

This is where your fibular collateral ligament is arising.

10:10

This is your aqua, uh, ligament complex.

10:15

So again, when you're looking at the post lateral corner on

10:18

axial images, if you see any disruption or marked fluid

10:21

and edema here, you can, you can say

10:23

that there is a post lateral corner injury, of course, along

10:26

with your big tendons, which are your complete test tendon,

10:29

the fibular collateral ligament, and the biceps tendon.

10:32

Other things on, on axial images,

10:34

obviously you're looking at the,

10:36

the muscles and the tendons.

10:37

Um, you wanna look at this, uh, recess, which is

10:41

between the semimembranosus and medial head of gastro.

10:44

If there's fluid coming out through it that you call it

10:47

as baker's, uh, cyst, your medial, uh, muscles are GLIs,

10:51

sartorius, semiosis

10:54

and semitendinosis, medial head of gastro,

10:57

lateral head of gastro.

10:59

And then here is your biceps

11:01

with the biceps tend inserting onto the proximal.

11:05

So that's, uh, and then lastly, the neurovascular bundle.

11:08

So that's your, uh, popal neurovascular bundle.

11:11

That's your tibial nerve. More proximally.

11:14

Uh, it's the sciatic nerve

11:17

that bifurcates into the tibial nerve,

11:19

and that's your common peronial nerve.

11:21

And then this common peronial nerve goes anteriorly, wraps

11:25

around the fibular neck to supply the muscles

11:27

of the anterior and lateral leg compartments.

11:30

Okay? So that's how I approach a knee on mr.

11:34

And, uh, in this case, the diagnosis is,

11:36

the main diagnosis abnormality is this proximal particular

11:40

tendinosis and, uh,

11:44

the PrepU plate delamination.

11:49

Okay. Any questions on this one, or should we move on to the

11:57

hearing?

11:58

None. So let's move on to the second case.

12:00

I think second case is important.

12:02

Uh, I would like to spend some, uh, time on it.

12:05

Um, this is, um,

12:11

let's see the history.

12:12

So, uh, this patient had,

12:18

hmm, m it's a long history, right?

12:19

Anterior butler pain, sharp pain from crepitus, instability,

12:24

weakness, uh, increased pain with weight,

12:26

all since 30 years, fractured right knee 12 years ago,

12:30

realigned, right butler.

12:31

Okay. So we look at the images, uh,

12:34

they have a long history, um, of anterior knee pain.

12:38

Uh, we can, um, starting with the axial images, um,

12:42

this thing that stands out on the axial images anteriorly in

12:45

the petillo femoral compartment is this chronic

12:49

complete full thickness cartilage loss.

12:50

Along the lateral petula, uh,

12:52

you can see the osteos Provence.

12:54

That means an os The osteophytes have also formed.

12:57

So this is a longstanding, um, uh, moderate to advanced, uh,

13:01

patillo femoral joint osteoarthritis.

13:03

The other thing is the shape of the trochlear,

13:05

more superiorly, it's quite funny.

13:07

It's more flattened. Um, so this is, um,

13:09

uh, trochlear dysplasia.

13:11

So as we can, as we scroll down, the depth comes back.

13:14

So this is just more of superior trochlear dysplasia.

13:17

Sometimes dysplasia is just confined

13:19

to the superior trochlear.

13:20

And those are the cases that often get missed

13:22

because people look at the over here

13:25

and say, oh, there is trochlear groove.

13:26

So there's no trochlear dysplasia,

13:28

but know that a lot

13:29

of these dysplasia cases are just in the superior trochlear.

13:32

And that is why we do these measurements

13:33

for trochlear dysplasia,

13:35

approximately three centimeters proximal to the joint line.

13:39

So there's evidence of trochlear dysplasia, um, um, uh, uh,

13:43

chronic cartilage loss.

13:47

This will be your MPFL, that's your lateral vernacular.

13:52

Um, other posterior soft tissues are looking, okay.

13:55

There is a susceptibility here along the tial tuberosity.

13:59

So screw along the table.

14:00

Tuberosity suggests they had a prior tuberosity, uh,

14:04

transfer osteotomy, which is a surgery

14:07

for petillo femoral instability when people have clinically

14:11

that increased Q angle.

14:13

Um, um, they have this lateralized tibial tuberosity, um,

14:18

which on imaging translates to increased, uh, TTPG distance,

14:22

um, which stands for tibial tuberosity,

14:24

trochlear groove distance.

14:26

Um, and that means those patients have increased risk

14:29

for lateral particular dislocation.

14:31

So if they have, uh, uh, the, if the important cause

14:35

of petal femoral instability is, uh, this lateralized

14:39

to build tuberosity, so that

14:41

what they do is they cut petal tuberosity.

14:42

So that's osteotomy, move it medially

14:45

and fix it with a screw.

14:46

So that's Erbil vocal, um, uh, transfer osteotomy,

14:50

which is done for, um, one of the surgeries

14:53

for particular femoral instability.

14:55

Okay, let's look at the sagittate images.

14:57

Looking at everything else,

14:59

a medial meniscus has some intrasubstance degeneration.

15:01

I didn't see the signal extending to the surface, uh,

15:05

cartilage looks fine.

15:08

Cruciate ligament, again, strate appearance

15:10

of the ACL, but looks, okay.

15:12

PCL looks okay, lateral meniscus.

15:15

And when you're looking at the lateral compartment,

15:17

you can see this is the trochlear articular surface more

15:19

anteriorly, and you can evaluate the particular trochlear,

15:22

um, articular cartilage and sagittal images as well.

15:25

And you can see complete loss of articular cartilage

15:27

and subc chondral cystic changes.

15:29

So this is great for cartilage loss all

15:30

along the lateral trochlea.

15:34

Again, complete cartilage loss along the patella,

15:37

the extensive mechanism, otherwise it's looking okay.

15:40

And you have that susceptibility from the screw

15:45

that's looking at the coronal images.

15:47

Uh, again, from front to back medial meniscus, again,

15:50

I just see intrasubstance degeneration.

15:52

Cartilage is okay. MCL is okay.

15:56

Lateral meniscus, lateral compartment cartilage.

16:00

And the collateral ligament complex starting from the IT

16:03

band, uh, the populous tendon, the FCL biceps.

16:09

So everything is looking good except, um,

16:12

so we basically have PLO femoral arthritis with, uh,

16:15

evidence of underlying PLO femoral instability

16:18

from tral dysplasia.

16:20

And they've already been operated for, um, um, uh,

16:24

bil tubal, um, transfer.

16:26

So they've had that osteotomy.

16:28

So evaluating

16:30

and identifying, uh, PLO femoral um, instability, uh,

16:35

is really important on MR imaging for sometimes, um, um,

16:39

this small degree of cochlear dysplasia

16:42

and evidence of PLO femoral instability is just an

16:45

incidental finding on imaging,

16:46

and patients eventually can have problems from it.

16:51

So it's important to diagnose.

16:53

So, um, we look at some measurements that are done to, uh,

16:57

look for instability.

16:58

And those are, um,

16:59

taken this from a nice radiographics article, uh,

17:02

in cell cell ratio, which you probably know, uh,

17:05

we do that very commonly.

17:07

But, um, these days it's the caton, uh,

17:10

CATON Dish AMP index, uh, that is more specific

17:13

for patar height rather than in cell salvati ratio.

17:17

The values are more or less similar.

17:19

So anything more than 1.2 to 1.3 as abnormal.

17:22

We look for patar lateral tilting of the patella.

17:26

We look for the trochlear depth.

17:27

We'd look for the trochlear sulcal angle,

17:29

and we look for the KTT G distance.

17:32

So some schematics to show how these measure.

17:34

So, uh, this blue, uh, lines demonstrate

17:37

how we measure in cell salvati ratio, which is the length

17:40

of the particular to the length of the particular tendon.

17:42

And A divided by B is in cell.

17:45

If it's more than 1.4, we say it's a high,

17:49

but I said, uh, these days surgeons are using, um,

17:52

cat on damp index more, which is the length

17:55

of the particular articular surface to, uh,

17:58

from the inferior point of the particular articular surface

18:01

to the most closest point of the anterior tibia.

18:03

So this is, uh, C by D.

18:05

Again, if that's more than 1.2 to 1.5, that's abnormal.

18:09

Suggest high riding patella.

18:11

There's something known as, uh, patillo trochlear index,

18:13

where, um, you see how much is the overlap, uh,

18:17

of the articular cartilage, uh, of the patella and,

18:20

and trochlear and, and a, uh, extended position.

18:24

So f is the, uh, trochlear cartilage,

18:27

which is overlapped by butler cartilage.

18:29

And D is the length of the butler cartilage.

18:31

So obviously the less this is,

18:32

that means it's a high riding part to look for partr tilt.

18:37

Uh, we compare the position of the butler relative

18:39

to the condylar axis, so the line drawn along the medial

18:43

and lateral femoral condyles.

18:45

So what's the angle of the putler relative to this line?

18:47

The more, like, usually it should be parallel,

18:49

and if it's laterally tilted,

18:51

this angle is going to be more.

18:53

So this is a predisposition for putler femoral instability

18:56

or, uh, uh, putler dislocation,

18:59

lateral particular dislocation.

19:01

Uh, this is just a, a way to measure, um,

19:04

uh, trochlear depth.

19:05

Um, so we measure the height of the, the medial trochlear,

19:08

the lateral trochlear and the groove,

19:11

and, uh, add these two up, average it out,

19:14

and see if it's bs.

19:16

It should be at least three more than three millimeters,

19:19

less than A plus C, and divided by two, the average of a NC.

19:24

And if it's, um,

19:26

the difference is less than three millimeters

19:28

between the average of A NC

19:29

and B means there is, um, the depth isn't enough.

19:33

So it's a shallow cochlear groove,

19:35

or it's, it's totally dysplasia.

19:37

Um, this is, um, um, and, and,

19:41

and we talk about butler femoral instability.

19:42

It's given in your, uh, PDF handouts that you have.

19:45

It's, uh, we also talk about the butler shape

19:48

and the, the, there's dejo classification

19:50

for trochlear, uh, morphology.

19:53

So, um, one of the ways is, um, the things that change

19:57

with trochlear dysplasia is the, uh, the length

20:00

of the medial and the lateral trochlea.

20:03

So, uh, in trochlear dysplasia,

20:05

the medial facet is much smaller than the lateral facet.

20:08

So you can measure the length of the medial

20:10

and lateral facets and see if it's within normal

20:13

range or if it's abnormal.

20:15

This is, um, uh, the image looks complex,

20:19

but this is exactly how we measure ttt distance on imaging.

20:23

Um, you can do it on axial MR images or axial CT images,

20:27

but, um, it requests superimposition of two images,

20:30

or you can just scroll your stack

20:32

and make sure you're at the right, same reference point,

20:34

and then measure the distances there.

20:36

So, uh, we measure the, uh, the point, like,

20:40

or pick up the point where the trochlear groove is.

20:43

So we, we have one image

20:44

where you have the trochlear groove.

20:47

We determine where the center of the tr uh,

20:49

or where the trochlear groove is.

20:51

Then we scroll inferiorly till we come

20:53

to the tibial tuberosity,

20:54

and we see the point, uh, the center of the table tuberosity

20:58

and measure the distance between the two.

21:00

So that's your TTTG distance tibial tuberosity,

21:03

trochlear groove distance.

21:05

If this distance is more than 1.8, that means, um,

21:08

the patient has lateralized stability tuberosity,

21:11

and it's an important risk factor

21:12

for particular dislocation.

21:14

So either use superimposed two images

21:17

or pick where the prole groove is on one axial image,

21:21

scroll all the way down to the table tuberosity,

21:23

and then again, measure how far out your

21:25

to build tuberosity is from that dis uh, point.

21:29

Um, and then, um, the femoral, uh,

21:34

rotation is also an important contributor

21:35

to petillo femoral instability.

21:37

And nowadays, more and more surgeons are asking for, uh,

21:41

femoral version angles of as a preoperative evaluation.

21:46

So, uh, here typically we, it's done on a ct,

21:49

it's separate imaging from

21:51

and, um, not the MR knee

21:53

where we do one axial through the hip.

21:56

We determine the angle of the femoral neck relative

21:58

to the horizontal, or, uh, basically again,

22:02

it requests superimposition.

22:03

We are measuring this angle relative to the condylar axis.

22:07

Uh, so either you can superimpose those images

22:09

or you can measure this angle

22:10

and then go down at the level of the knee condyles

22:13

and see what the condylar line is,

22:15

and then determine this angle between the femoral neck

22:18

and the condylar line.

22:20

So, um, there are values here.

22:23

Um, so depending upon how much is the degree

22:26

of femoral rotation, uh, if it's more a, a lot more

22:30

or a lot less, all that can predispose to femoral, um,

22:33

uh, butler instability.

22:36

So, uh, um, this is the chart from

22:39

that same radiographics article where, uh,

22:41

they tell you based on what's the main abnormality,

22:44

which is predisposing a person

22:45

to develop petal femoral instability,

22:47

there are different surgical options.

22:49

So if it's, um, just instability

22:52

and it's from A-V-M-P-F-L,

22:53

they can do an MPFL reconstruction.

22:55

If it's access lateral particular tilt

22:58

and subluxation, if it's tr clear dysplasia,

23:01

they can do a trop plasty.

23:02

Uh, they correct for the morphology for TT TG distance.

23:06

They will do this stable tubercle transfer osteotomy.

23:10

And if there is increased femoral inversion

23:12

or tubial torsion, then they need

23:14

to do an additional d rotation osteotomy to correct for

23:16

that rotation, then decrease the chance

23:18

of particular femoral instability.

23:20

And a lot of times they do a combination of two surgeries

23:23

because trop plasty is, um, not a widely performed surgery.

23:28

A lot of the surgeons, um, do a combination

23:30

of tubial tubercle osteotomy and MPFL reconstruction.

23:33

That's the most common surgery that we see in our practice

23:35

for cases of particular instability.

23:38

And when we are, just to summarize,

23:39

when we are reading these cases, the things

23:41

that we are looking for on MR imaging, uh,

23:44

we will definitely comment on if the patula is tracking

23:47

centrally or not, if there is any lateral putler tilt

23:50

or subluxation, the height of the patella

23:52

by giving katon damp index if it's high riding

23:54

or not, if there's any evidence of, uh,

23:57

fat pad impingement from a high riding patella,

23:59

if there's any evidence of trla dysplasia

24:01

and not just uniformly, we go three centimeters

24:04

above the joint line and determine if there is, uh,

24:07

isolated, uh, superior tole dysplasia or not.

24:10

Um, then, um, the TT DD distance,

24:14

and once they have known documented, uh, part

24:17

of femoral instability and the surgeon is planning

24:19

to operate as a part of pre-op evaluation, they will try

24:23

to determine the lower extremity alignment

24:25

by doing the standing, um, like those grams

24:28

or on axial ct, determine the degree of,

24:30

uh, femoral rotation.

24:32

So that's the entire workup for, um,

24:35

part of femoral instability.

24:36

And, um, as we saw in that this case, that person has

24:41

unrecognized perlo femoral instability

24:43

that either dislocating re their recurrent dislocators, uh,

24:46

they'll eventually develop cartilage loss in the perlo

24:49

femoral joint, and, um,

24:51

just starts osteoarthritis in the, in the knee joint with that.

24:55

Okay, that was case two.

24:59

And, uh, in interest of time, um, then I would just, um,

25:02

go with the important cases.

25:04

So I would like to go case, go over case five from week one.

25:12

Start with the sagittal images.

25:15

So right when we start from your, uh,

25:18

with the sagittal images medial side, we can see

25:21

that the medial meniscus is abnormal.

25:23

It looks markedly attenuated.

25:26

It has that abnormal signal within it, a linear signal

25:29

that extends to the articular surface.

25:30

So there's definitely a meniscal tear.

25:33

And now as we start seeing two components here, so

25:36

that's the anterior horn,

25:37

and then there is another fragment here,

25:41

and it's continuous with this.

25:43

And this is what is known as the double PCL sign.

25:45

So it's a, this is, that means it is a bucket handle tear

25:49

of the medial meniscus

25:50

where there is extensive longitudinal tearing

25:52

of the medial meniscus.

25:53

And the inner half the tone, inner half

25:56

of the meniscus flips into the intercondylar notch

25:59

and gives rise to the double PCL sign.

26:03

It's interesting that this case shows the, another, uh,

26:07

important sign of, uh, bucket handle meniscal tears is this,

26:11

which is known as double delta sign.

26:13

When you see two triangles back to back of the meniscus,

26:16

ideally should, there should be one triangle anteriorly,

26:18

that's the anterior horn and one triangle posteriorly,

26:20

which is the posterior horn.

26:22

But here you're seeing two triangles anteriorly.

26:24

So that's called double delta sign.

26:25

This is when the flip is more anterior.

26:27

And in this case, the flip is more like anterior

26:30

and towards the center of the joints.

26:32

And that's why you're getting both signs,

26:34

the double delta sign

26:36

and the uh, uh, the double PCL sign.

26:41

So that's the flipped meniscus,

26:44

that's the PCL, which looks okay.

26:46

Lateral meniscus looks fine,

26:49

cartilage is looking fine,

26:53

extensor mechanism is looking, okay.

26:55

The butler femoral articular cartilage looks okay.

26:57

There's a big joint diffusion on the

27:02

coronal images again, um, sorry,

27:05

starting from the medial side again,

27:07

attenuated medial meniscus, you can see

27:09

that flipped meniscal tissue

27:11

and the intercondylar notch, I lean the intercondylar notch.

27:14

You should have only the ACL

27:15

and the pcl if there's a third structure

27:17

to determine if typically it's a flipped meniscal fragment

27:19

and sometimes there are loose bodies.

27:24

So MCL looks okay,

27:26

all the collateral ligament structures are fine.

27:32

On the axial images, there's big joint effusion.

27:34

That's a medial, like a small baker cyst.

27:43

So, um, that's an example of bucket angle tear.

27:46

These are important because these are orthopedic urgencies,

27:49

um, can lock the joint

27:51

and, uh, they have to be repaired as soon as possible so

27:55

that we can preserve the meniscal tissue as much as we can

27:58

because these are simple clean tears.

27:59

And if you put that, reduce that fragment, put it back

28:02

and repair it, the patient can have good outcomes from it.

28:06

Where if you just let it be for a long time, first of all,

28:09

the pain, the patient has an excruciating pain,

28:11

it causes locking of the joint,

28:13

and eventually the torn fragment will get disintegrated,

28:17

frayed, and then the repair will be not possible.

28:20

And eventually the patient will not be left

28:22

with enough meniscal tissue.

28:23

And we know that if there isn't enough meniscal tissue,

28:27

it sets the stage for osteoarthritis of the knee.

28:30

So especially in a young individual, uh,

28:32

if it's an acute flip, uh, uh,

28:34

it should be operated as soon as possible.

28:36

And that's the importance of picking up these flipped

28:39

meniscal tears that they need surgery as soon

28:42

as possible to have good outcomes.

28:45

So that's why I wanna do this case.

28:48

Let's, uh, should we do case four? Let's do case four.

28:52

That was important as well.

29:03

So this is a pediatric knee, uh, again,

29:08

from starting with the sagittal images, um, fluid sensitive,

29:12

fat saturated, the meniscal cartilage look fine.

29:15

You can see there's a big joint effusion.

29:17

There's a lot of edema,

29:18

and there's difference in how the, the growth plate

29:22

of the proximal tib and the still femur, it looks different.

29:24

There's a lot more fluid,

29:26

a lot more signal abnormality along the distal femur.

29:29

The cruciate ligaments are okay,

29:31

there's a big joint effusion,

29:33

there's mar edema in the proximal fibula.

29:37

The extensor mechanism is looking, okay,

29:44

Let's look at the coronal images.

29:48

MCL is intact, the cruciates are intact.

29:52

The menisci and articular cartilage looks good.

29:55

So you can see the fracture line in the proximal fibula.

29:58

So there is a fracture of the proximal fibula

30:00

that's confined to the epiphysis,

30:02

extends to the growth plate.

30:04

So anytime you have a fracture in an, uh, uh, adolescent

30:08

with open growth plate,

30:09

we use the Salter Harris classification.

30:12

And as we look at the distal femur,

30:14

there's another fracture here in the metaphysis

30:16

of the distal femur that extends to,

30:18

it's predominantly in the metaphysis,

30:20

extends to the growth plate.

30:22

And then more anteriorly,

30:24

there is signal in the epiphysis as well.

30:26

So this will be a sort of four, um, sort Harris, um,

30:32

type four fracture of the distal femur.

30:34

And you see a lot of heterogeneity here.

30:36

Just see this, um, there's a stripping of the periosteum,

30:41

and this dark stuff is acute hemorrhage.

30:43

So this, there is subperiosteal hematoma.

30:45

Let's look at the axial images

30:47

that probably show this better.

30:49

So you can see that this is the distal femur,

30:51

and as compared, if you compare the medial

30:54

to the lateral side here,

30:55

the periosteum is flush with the bone.

30:57

And here the periosteum is lifted off post medially,

31:01

and you can see the dark stuff

31:03

between the bone and the periosteum.

31:05

So that's your subperiosteal hematoma.

31:07

And quite interestingly,

31:09

because of high pressure, you can see

31:11

that hematoma decompressing into the post

31:15

medial soft tissues.

31:16

This is your biceps muscles.

31:17

So deep with the distal biceps, you have that hematoma

31:20

that's decompressing from that superior OTE hemorrhage.

31:24

So there are two sort Harris fracture sort Harris, four

31:27

of the distal femur with a big subperiosteal hematoma

31:30

that's decompressing into the soft tissues,

31:32

big joint effusion and the proximal fibular fraction.

31:39

Okay, so, uh, well I just wanted to show you

31:42

because the pediatric needs look a little different than

31:46

adult needs with those open growth plates.

31:48

And, um, some of the complications.

31:50

One of the most important complications of,

31:52

so sort heart fractures, which involve the growth plate is

31:55

of development of fial bars.

31:57

Uh, the growth plate will fuse early as part

32:00

of fracture healing, uh, creates a fial bar

32:02

and results in growth disturbances and,

32:04

and adults as these people grow.

32:09

Can I please ask why the lesion in the metaphysis looked

32:12

ring shaped on the coronal?

32:14

Yeah, it's just the, uh, combination of

32:17

fracture line edema and the hemorrhage.

32:20

So there is actually both intramedullary

32:22

and the, the hemorrhage

32:24

and yeah, it actually looks like a for a second,

32:26

I thought, is it just infarc?

32:28

But you have the, that tells you that they're not secular,

32:31

so they don't have any predisposition

32:33

for developing an infarct.

32:35

And this is just a case of trauma.

32:37

So, uh, it's just a fracture line

32:39

that's just a fracture line with narrow edema,

32:41

and it's the intramedullary hemorrhage, like over here, all

32:44

that dark stuff is hemorrhage,

32:46

which is same intramedullary hemorrhage,

32:49

decompresses into the sub periosteum

32:51

and eventually decompresses into the soft tissues.

32:55

Yeah.

33:00

Okay. Moving on to week two.

33:04

Let's see, what are the most important cases in week two?

33:06

We'll do case one osteo test against the diagnosis. There

33:17

We start with, so again, this is also a pediatric knee,

33:21

and we see on the medial side meniscus is

33:24

okay, do you see that?

33:26

Uh, subc chondral abnormality in the posterior medial

33:29

femoral condyle altered signal, some cystic changes,

33:34

everything else is looking Okay.

33:36

Looking at the coronal images, this is a better depiction

33:40

of what you see here.

33:41

So basically, if you can see there is separation

33:44

of the articular cartilage.

33:46

And the looks like this.

33:47

There's like a little lucency

33:49

or hyper signal that's trying

33:51

to separate an osteochondral fragment

33:53

from the rest of the bone.

33:55

So in this age group, um, this is, uh, fairly typical for

33:58

what is known as an osteo descants of the knee.

34:02

Basically, you have to identify, uh,

34:04

what you see is an osteochondral fragment that is trying

34:08

to separate from the underlying bone.

34:12

So, um, what is, um, what I just wanted

34:16

to pull up my presentation.

34:23

So what iser testic cancer, it's aseptic separation

34:26

of the osteochondral fragment from the rest of the bone.

34:29

As that, that's what we see on imaging.

34:32

It's a developmental thing and nobody knows the exact cause.

34:34

There's several hypothesis for how this happens.

34:37

Um, some people feel is just, uh, developmental

34:40

and just aseptic separation, something.

34:42

It's because of repetitive microtrauma, something

34:44

that there is underlying avascular necrosis.

34:47

Um, sometimes, uh,

34:49

developmental means there is like a delayed

34:51

or there's a growth, uh, rate dis difference between, uh,

34:55

that fragment and the rest

34:57

of the bone and they look different.

34:59

Um, there's a lot of times some

35:00

of them can heal spontaneously

35:03

and some will require surgical fixation.

35:06

Most common locations are the lateral aspect

35:08

of the medial femoral condyle.

35:10

Uh, 75% are on in that area.

35:13

Then weight bearing surface of the medial

35:16

and lateral femoral condyles,

35:17

and 5% in the, so once, uh, how, uh,

35:22

is imaging important in these cases?

35:24

First is to make the diagnosis

35:26

that it's an osteochondral lesion.

35:27

That's the abnormality presenting in patient symptoms.

35:30

And the second most important thing to do on imaging is

35:33

to stage that lesion.

35:34

That's very important because that's

35:35

what determines the management.

35:37

So it determine the size, the location

35:39

and staging is to tell whether it's, uh, uh,

35:41

stable versus an unstable lesion.

35:43

Unstable region, uh,

35:44

lesions will require surgical treatment.

35:47

So stage, uh, basically the difference between stage one

35:51

and two and the rest of the fragments is when

35:54

in stage three, four,

35:55

and five, the, the fragment is completely separate, uh,

36:00

from the underlying bone.

36:02

Like that means there should be a nice fluid cleft

36:05

all along its base.

36:07

So if stage three is, if it's detached

36:09

and non-displaced, stage four, if it gets displaced,

36:14

either partly or completely,

36:15

it's like completely dislodges from the groove

36:17

and becomes a loose body in the joint.

36:20

And stage five is

36:21

because it's disruption of the articular cartilage,

36:23

it can incite the process of osteoarthritis.

36:26

So that's stage five. So anytime you see an osteochondral

36:30

fragment, uh, we have

36:32

to tell whether it's stable versus unstable.

36:33

Signs of instability are a clear fluid cleft at the base

36:37

or subc chondral edema

36:39

and cystic changes in the bone, which is

36:41

underneath the sub osteochondral lesion.

36:43

So these are your signs of,

36:44

or if it's a displaced fragment,

36:46

if it's become a loose body, then of it,

36:48

it's been an unstable lesion.

36:50

Some of the treatment options are smaller lesions can just

36:53

be debrided, uh,

36:55

or if it's a completely detached separated fragment may

36:58

require surgical fixation.

36:59

They can just fix it with screws.

37:01

Sometimes they, the fragment is like unstable

37:05

and not, uh, repairable, then you have to just take it out.

37:08

And what to do is that denuded area of bone,

37:11

you create micro fractures.

37:13

So there is increased bleeding from the surface

37:15

and it'll promote, um, um, uh, bone and cartilage healing.

37:20

And, uh, more complex surgeries

37:21

with better outcomes are when you can do an

37:24

osteochondral grafting.

37:26

So, uh, auto graft is, um, um,

37:30

like can take osteochondral autographs

37:33

and plug it in that area of the deficient area.

37:36

We can do allografts, like you can take the, uh,

37:39

osteochondral fragments from the non-weight bearing portion

37:42

of the joint and move them

37:44

and put them in the weight bearing part

37:46

or autologous chondrocyte implantation.

37:48

Sometimes you can take the chondrocytes,

37:49

grow them out in the lab, and then put them back

37:52

and let them form the articular cartilage back.

37:55

So there's several, uh, surgeries done for this.

37:58

Um, and you may also get

38:00

to see if you're in dedicated orthopedic practice, uh,

38:03

post-op follow-ups.

38:04

And then we have to, um, uh, determine

38:08

if there is appropriate healing for that, uh,

38:11

osteochondral lesion repair.

38:13

And there's this whole mohart score, um, that is that, uh,

38:17

as, uh, radiologists

38:19

or imagers we used on imaging to tell if

38:21

that thing is healing well or not.

38:25

Okay. Uh, let's see,

38:33

um, other, let's do case four from week two.

38:45

Starting from the, again,

38:47

with the sagittal images medial side,

38:49

you can see there's abnormal signal in the posterior horn

38:51

of the medial meniscus.

38:52

That signal is more vertical in the

38:54

periphery of the medial meniscus.

38:56

So there is a vertical tear in the periphery

38:59

of the posterior ho of the medial meniscus.

39:01

And just by looking at this, uh,

39:05

we should be looking for ACL tears.

39:06

We should know that vertical tears along the posterior hos

39:09

of medial lateral meniscus have a high association

39:12

with associated crochet ligament injuries.

39:14

So anytime I see this, I know that probably going

39:17

to encounter an ACL tear, and that's what it is.

39:19

There's a complete ACL disruption in it's mid substance.

39:22

Uh, PCL looks okay, lateral meniscus,

39:27

lateral compartment articular calculation looks fine.

39:30

Um, can see little CRO lateral fat edema.

39:33

So it's a high writing patula.

39:35

Otherwise, the extens extensive mechanism is okay

39:37

looking at the coronal images.

39:40

So anytime there is a cruciate ligament injury,

39:43

we've identified a cruciate ligament injury.

39:44

We've identified a meniscal injury.

39:46

Uh, we have to make sure there is no collateral ligament

39:49

injury because collateral ligament injuries can result in

39:51

instability if there's associated with EC tears.

39:55

So, uh, medial collateral ligament looks okay.

39:58

Uh, lateral collateral ligament

40:00

structures actually look fine.

40:01

So there's no post medial or post lateral co injury.

40:05

So this, uh, vertical tear of the posterior hand

40:08

of medial meniscal in the periphery, this is known

40:10

as ramp lesion.

40:11

Um, recently it's everybody's talking about these,

40:15

it's become important, um,

40:17

because these are the tests, um,

40:19

that often can get missed both on imaging

40:23

because they're far out in the periphery.

40:25

And may, we may think that, oh, this is just that fluid

40:27

between the meniscus and the capsule.

40:30

It's hard to pick up an arthroscopy

40:32

because the surgeon has to go all the way far at the back

40:34

and they come from that anterior portal

40:36

and dip into that a posterior joint space to identify it.

40:40

So if you don't alert them on imaging,

40:42

they probably won't probe, uh, at the back as much,

40:45

and they can completely miss it too.

40:48

And the significance of missing these meniscal tears is if

40:51

this tear is not taken care of,

40:54

and, uh, ACL reconstruction is performed, they can come

40:57

with a, this tear will propagate.

40:59

It's a vertical tear, it'll propagate in the body

41:02

and the interior horn and can come as a bucket handle, tear

41:06

after ACL surgery.

41:08

And people think that the surgery has done something that,

41:11

you know, they're coming back with a problem after surgery.

41:15

So, um, and obviously medial meniscus,

41:18

menal tissue is important.

41:19

It at this early stage, if you, if the surgeon repairs it,

41:23

they're much better outcomes rather than when it comes at a

41:25

later stage when it's much more extensive there,

41:28

there are high chances of losing that meniscal tissue

41:30

and early osteoarthritis.

41:31

So that's a significance and that's why,

41:33

and these are called ramp lesions.

41:35

Um, and just to show you my presentation of, um,

41:43

so, um, this again is an article in recent article from

41:46

Radiographics that talks about the anatomy.

41:49

So the medial meniscus should be flush

41:50

with the joint capsule, and these are the, uh,

41:53

different zones of the meniscus and the capsule.

41:56

And, um, as you go to the periphery,

41:59

you like you're ramping up.

42:00

So that's, that's why these are called ramp lesions.

42:03

So, um, this where the capsule is flush

42:07

with the meniscus, that's your meniscus capsular junction.

42:10

The most, uh, periphery

42:12

of the meniscus is your red red zone.

42:15

Then in between is the red white zone,

42:17

and then the innermost portion

42:19

of the meniscus is the white zone.

42:20

White zone is the most avascular white comes

42:23

from a vascularity.

42:24

So tears in this area don't heal well,

42:26

whereas tears in red zone can heal spontaneously

42:29

because of a better vascularity.

42:30

So that's the only advantage of these lesions is

42:34

they do get missed, but some of them

42:36

will heal spontaneously.

42:38

The problem is when they don't heal spontaneously

42:40

and propagate, but they are in the red, red zone.

42:43

Okay? And, um, that's the arthroscopy view of the, the,

42:47

that's the medial meniscus flush with that joint capsule.

42:52

So there's a classification for these ramp lesions.

42:55

One is just, uh, edema at the meniscal capsular junction.

42:59

Two is when you have the tear in,

43:01

like an incomplete tear in the periphery.

43:04

Three more on the superior side.

43:05

Three is also an incomplete tear in the periphery,

43:07

but on the inferior side, four is a complete vertical tear,

43:11

uh, in the posterior horn.

43:13

And five is a tear

43:15

and a meniscal capsular separation or a complex tear.

43:18

So this one was looking like this,

43:20

it was a type three ramp lesion.

43:23

So again, these are important, so

43:28

now know how they look like, uh, look for them.

43:31

Um, so with ACL tears,

43:33

the checklist is once you've identified ACL tear,

43:36

make sure there are no meniscal tears,

43:37

particularly you're scrutinizing the posterior horns

43:40

and of them both medial and lateral meniscal.

43:43

And you're carefully looking at the collateral ligaments,

43:47

uh, because they're, the pivot mechanism

43:49

of injury can also lead to, uh,

43:52

post lateral corona injuries.

43:54

And we'll talk about those. So those are important

43:56

to identify and talk about.

43:59

Okay, we can, um, move on to,

44:04

uh, week, third week.

44:08

And the two most important cases are let's do case

44:12

one and then case four.

44:23

Okay. So, um, starting with the sagittals,

44:28

so again, that little increased signal at the

44:30

meniscocapsular junction.

44:32

So maybe just back one ramp lesion,

44:35

no real tear in the periphery of the medial meniscus.

44:41

The cruciate ligaments are actually okay.

44:43

There's a lot of, um,

44:44

marrow edema in the lateral femoral condyle

44:47

with an osteochondral impaction injury.

44:51

The extensive mechanism is, okay, big joint effusion,

44:57

and you look at the coronal images,

44:58

the MCL is grossly abnormal, so it's a complete tear

45:01

of the medial collateral ligament from

45:03

its femoral attachment.

45:06

And there is an impaction injury on

45:08

the lateral femoral conland.

45:09

So just this pattern without ACL

45:11

or PCL injury, it a valgus mechanism of force, right?

45:16

It stretched out the medial side.

45:18

So the MCL got on it impacted the lateral side,

45:21

so you can impact, um, um,

45:23

lateral femoral condyle impaction injury.

45:26

So, and then this is where the MCL attaches.

45:28

So if you see there's a lot of edema along the entire medial

45:31

and post medial complex

45:33

and even confusion of the femoral attachment of the MPFL.

45:37

So it's injury to all the medial structures of the knee.

45:40

So with this, we can discuss the, the,

45:43

the post medial corner of the knee quickly.

45:47

So that's your post medial complex. It has five components.

45:51

The semimembranosus tendon, the medial head of, um, uh,

45:54

sorry, uh, the posterior on, uh, of the medial meniscus,

45:59

the posterior oblique ligament, the oblique, uh, uh,

46:04

oblique popal ligament, the poster medial joint capsule,

46:08

and the posterior hand of the medial meniscus.

46:10

So this is how they're listed.

46:11

That's your superficial MCL, just posterior

46:14

to the superficial MCL.

46:16

The part of the joint capsule is posterior oblique ligament.

46:19

More towards the center,

46:21

it's the oblique popliteus ligament.

46:24

Here you have the posterior hand of the medial meniscus,

46:27

that's your semimembranosus tendon.

46:30

So all these structures from the post medial corner,

46:33

and this is where you're looking for, uh, to make sure

46:36

that there is no post medial corner injury.

46:39

So these are examples of, this is an example of,

46:41

you can see this is the MCL.

46:43

So this is the tear of the posterior oblique ligament,

46:46

which is slightly more posterior to the attachment of the,

46:49

uh, medial collateral ligament.

46:51

And on this image, they're showing just the sprain

46:54

of the poster, median joint capsule,

46:55

including the posterior oblique ligament

46:58

and the oblique pletus ligament Here, the MCL is intact.

47:01

So just examples from literature. Okay.

47:06

Um, and then, um,

47:12

Case two in contrast shows nice examples.

47:16

Uh, it, it's a nice example of postal lateral corona injury.

47:21

Let's start from the medial side.

47:22

Again, a lot of edema, grossly abnormal structures.

47:25

Medial meniscus, I've hardly seen any

47:27

normal meniscal tissue.

47:29

There is a micro fracture here.

47:32

And again, I'm starting to get a double delta sign,

47:34

so I know it's like a flipped meniscal tear.

47:36

There's a double PCL,

47:37

so it's a bucket handle medial meniscal tear.

47:41

So even that, so this is lateral meniscus.

47:43

Also, there is a bucket handle tear

47:45

because the posterior ho is missing.

47:46

And I have two hos anteriorly,

47:48

that's a double, uh, dental sign.

47:50

Um, so both menisci have, uh, uh, uh, bucket handle tears,

47:55

marrow contusions, lateral femoral condyle,

47:58

posterior lateral tibial plateau

48:00

adjusting pivot shift injury.

48:01

There's also injury to the proximal fibula where the FCL

48:05

and the biceps tendon insert.

48:07

So that will amount to post lateral corona injury.

48:10

And we miss this part that there's a complete ACL tear.

48:15

Let's look at the coronal images to make sure

48:20

that the only coronal set that we have here.

48:22

Yeah, so MCL is okay, uh,

48:24

and we looked at the, the fibular fracture where the, um,

48:28

the FCL and biceps are attaching that was fractured.

48:32

So that amounts to post later coronary injury.

48:36

So again, as I said, with ACL injuries, it's also important

48:40

to determine, um, if there are any associated minuscule

48:44

or collateral ligament injury.

48:45

So as I said earlier,

48:46

that lateral collateral ligament complex has multiple

48:49

structures forming the complex static stabilizers are the

48:53

FCL, the popo fibular ligament, arcuate ligament,

48:56

f fibular ligament iliotibial band,

48:58

and the interlateral ligament.

49:00

And the dynamic stabilizers are the pletus, the biceps,

49:04

and the lateral head of cast drop.

49:06

Now, these, um, these are the three most common structures

49:10

that, um, injury

49:11

to these will result in post lateral corona Instability

49:15

of this fcl l

49:16

and populus are big structures can be easily identified on

49:20

imaging popula fibrillar, uh,

49:22

it goes from the Pope Myo tendus junction

49:25

to the proximal fibula.

49:26

So there's an injury based on, there's,

49:28

there's localized edema in that area.

49:30

You can say that there is injury

49:31

to the Pope fibrillar ligament.

49:34

Okay? The other thing, um,

49:35

I think I can quickly go back on my presentation, I wanted

49:38

to show you the inter lateral ligament.

49:52

So this is also part

49:53

of the lateral collateral ligament complex.

49:54

There's one ligament that goes from the lateral femoral

49:57

condyle to the lateral tibial Plato.

49:59

And it's the aversion of this ligament that results in

50:01

that small sigon fracture along the, so if you see,

50:04

have a small aversion fracture along the lateral tibial

50:06

plate, call it as a sigon fracture, right?

50:09

So once you see a sigon fracture,

50:10

you know there's a high chance of ACL injury.

50:12

And this also implies post later coronary injury

50:15

because it's an aversion of this ligament known

50:18

as antola ligament, which is part

50:19

of the lateral collateral ligament complex.

50:22

So the significance is if, if, uh,

50:26

these collateral ligament injuries are not diagnosed at the

50:29

time of ACL injuries

50:30

and the surgeon does an ACL repair doesn't address the

50:33

collateral ligament injuries,

50:35

eventually the patient again will have, uh, earlier failure

50:39

of the ACL graft

50:41

because of persistent joint instability, right?

50:43

With lateral, they're going

50:45

to get postal lateral instability with medial structures,

50:48

the patient gets post medial instability.

50:51

So it's important to address the collateral ligaments, um,

50:55

um, injuries along with cruciate ligament injuries as well.

51:03

Let's look at case four, uh, from third week,

51:09

and if you have time, we'll do case three

51:10

because that's one of the,

51:12

these are the most difficult cases.

51:14

As we discussed earlier, that trauma is easy

51:17

to, um, diagnose.

51:19

It's the non-traumatic conditions

51:20

that sometimes can become more challenging.

51:23

So, um, probably an older person MCL is looking okay,

51:28

the cartilage is thin,

51:33

Lot of like synovitis in the intercondylar notch

51:37

signal in the anterior horn of the lateral meniscus.

51:42

There are areas of cartilage loss.

51:44

You can see some subcon edema

51:46

in the lateral femoral condyle.

51:48

So it's older person degeneration of the meniscal

51:51

and the cutlet synovitis in the joint.

51:54

And what we see here is it's the, the extensive mechanism

51:57

that's grossly abnormal.

51:59

So the quadricep tendon, the, the fibers are splayed out,

52:02

and there is some tissue that's

52:03

infiltrating the quadricep tendon.

52:04

The same tissue is extending into the

52:07

particular soft tissues,

52:09

and there is splitting of the butler tendon as well with

52:12

that intermediate signal, intensity soft tissue.

52:16

So this is something that, you know, it,

52:18

you can diagnose it, uh, there is

52:20

otherwise, like it's the location, it's,

52:22

that's the location, location, location.

52:24

That's, that's the most important

52:25

thing for the diagnosis here.

52:27

So you should know that if there is, in an older person,

52:30

especially in a male patient,

52:32

if there is soft tissue in the pre particular region,

52:34

which is complex, uh, looks slightly intermediate

52:37

to hypos signal intensity on T two weight images,

52:39

that's almost patho of gout.

52:42

So this, this is gout, as I said, there's probably not, um,

52:46

nothing specific except knowing the location.

52:49

And there is some, um, uh,

52:51

intermediate signal intensity, soft tissue there.

52:54

Eventually this soft tissue will cause erosions along

52:56

the superior pole of the Petula.

52:58

That's why erosion along the superior pole

53:00

of the Petula superior pole is also patholo para

53:03

because of that of gout.

53:05

It's because of that, um, classic location.

53:11

So I'll show you some more examples of gout, um,

53:15

that you'll get to see in your practice

53:17

and make the diagnosis easier.

53:20

So gout is, um, deposition of monosodium urate crystals in

53:24

and, and out the joint, uh, 20 times more common in males.

53:28

So think, um, 10 times

53:31

before giving a diagnosis of gout in a female

53:33

and female gout happens only in postmenopausal age group

53:38

because estrogen has a protective effect against gout.

53:41

And also like if they have c, k, d, long-term dialysis.

53:48

So most common locations are the first MTP joint

53:50

and then the pre butler area, we can get tophi.

53:54

So that soft tissue is basically tofus of gout leading

53:57

to anterior particular erosions, and the hand

53:59

and the wrists, the interal joints, MCP joints,

54:02

couple joints, and in elbow endocrinal bura.

54:05

So anytime patient presents with complex al bursitis,

54:08

you can don't have a real mechanical cause to explain it.

54:11

Think of gout. So again, this case, right?

54:15

So this, some people may just pass it on saying

54:17

that this is just complex, pre particular bursitis,

54:20

but they're so complex.

54:22

It's it's intermediate signal, it's not fluid signal, it's,

54:25

it's more of soft tissue signal intensity.

54:27

And even on, on radiographs, you can see that,

54:29

that there's certain density to that peclar soft tissue.

54:33

So that's, that's, that's count.

54:35

Another, uh, so there is this again, that

54:39

T two dark soft tissue causing a big erosion

54:41

in the distal fibula.

54:43

So this is your gout tophus resulting in, in, in,

54:46

in an erosion, uh, uh, juxta articular erosion

54:49

and see that density in the soft tissues

54:53

much denser than the oma soft tissues.

54:56

This was also an interesting case.

54:57

This patient presented with an elbow mass

55:00

was a male patient, um, didn't see much on radiographs.

55:04

And what we saw on, on, on mr was this,

55:08

this was the soft tissue, very ill-defined,

55:10

but dark soft tissue, right?

55:11

That's, that's the hallmark. Um, it's not bright.

55:14

It, uh, was not marginated.

55:16

There was a lot of this infiltration of the,

55:18

the triceps tendon thickened, uh, splaying of the fibers.

55:23

Again, this is your PrepU bursa, which gets outlined.

55:25

So the bursal walls are thickened, lot of edema,

55:28

and that is the dark soft tissue.

55:30

It almost looks like saturated subcutaneous fat.

55:32

But if you looked at a non fat set image, this was,

55:34

this was the dark soft tissue.

55:36

So location, location, right?

55:38

Posterior elbow,

55:39

dark ill-defined soft tissue causing inflammation,

55:42

thickening of the tendons,

55:44

and um, uh, I think this was the erosion

55:47

and a, a juxt erosion that's theno of gout.

55:51

Yeah, I mean, difficult if you don't know

55:53

of these manifestations,

55:54

and if you have a case, you're kind of thinking

55:57

what is the soft tissue, we call it

55:59

as a tumor, recommend biopsy.

56:00

But, um, just knowing these manifestations of gout,

56:05

if you make a diagnosis, then there's a simple test

56:08

of just doing urate levels and, um, and then,

56:13

and managing it medically.

56:15

Uh, dual energy CT is becoming really important

56:18

to pick up early cases of gout

56:19

because it can differentiate between

56:21

mineralization and calcification.

56:22

So these early, um,

56:24

tophus deposition in the soft tissues can be easily picked

56:27

up at dual energy ct.

56:30

Okay. Um, so yeah, we have time.

56:32

So one minute, so we can quickly look at case three,

56:34

because that was also a little challenging case.

56:44

Okay, just hold up sagittal images.

56:46

So it's a young, again, a pediatric patient.

56:49

Uh, oh, this was, this was the ACL avulsion, that's the,

56:53

that's not the case I was trying to discuss.

57:05

Okay. Yeah, this one, yeah, this is also pediatric knee.

57:09

Um, I don't think so.

57:10

There was any history of trauma,

57:12

but as you can scroll, there's a big joint effusion,

57:16

slight complexity to this effusion, right?

57:18

It's not, doesn't look really simple.

57:20

It has that little complexity to it.

57:25

And you see a little bone defect, like,

57:28

it's like a subc chondral cyst with edema.

57:30

So a kid should not really have a subc chondral cyst,

57:33

like unusual to, for them to develop this osteoarthritis,

57:38

kind of like cartilage loss and grade four cartilage loss

57:41

and having a subc chondral cyst.

57:43

When you put these two things together that in,

57:46

in a young patient,

57:47

if you have unexplained non-traumatic joint effusion,

57:50

which looks complex,

57:51

and then there's something kind, if you can make that out

57:55

that that's, it's a bone erosion, then just putting

57:58

that joint effusion

57:59

and erosion gives a diagnosis of, um,

58:02

inflammatory arthritis.

58:03

So this was a case of rheumatoid arthritis.

58:10

I'll show you some more manifestations of it.

58:13

So this is one, so keep that in mind.

58:15

Non-traumatic unexplained joint effusion with the,

58:19

if you just try to look for those subtle erosions,

58:21

periodical erosions

58:22

or try to look for associated,

58:24

like there'll be bone marrow edema,

58:26

there's a effusion in bone marrow edema, um,

58:28

no history of trauma.

58:30

You need to think of inflammatory arthritis

58:32

or infectious arthritis in those cases.

58:35

So some of the manifestations of inflammatory arthritis

58:38

as synovitis, tenno synovitis, bursitis.

58:40

So unexplained non mechanical tenno synovitis, bursitis.

58:44

Think of inflammatory arthropathy, bone marrow edema

58:46

with erosions we talked about.

58:48

So this, this, again, we've seen a couple cases now on mri.

58:52

This patient presented with this unexplained, um,

58:54

he was not a tennis player

58:56

or something that they'll get ECU tendinopathy,

58:58

but they had, uh, a lot of 10 synovitis joint effusion, uh,

59:03

in the distal radio joint along the ECU tendon just turned

59:06

out to be rheumatoid arthritis.

59:09

This is an example of, uh, uh, uh,

59:13

chronic rheumatoid arthritis involving the knee.

59:15

So see how this looks different from osteoarthritis.

59:18

There's more uniform joint space narrowing without much

59:21

osteophytes or subc chondral changes.

59:22

That's how we differentiate inflammatory arthropathy

59:25

from osteoarthritis.

59:26

And on, uh, on MR images, again,

59:28

there is just uniform cartilage loss without

59:31

much subc chondral changes.

59:32

And you see the joint effusion with complexity in it.

59:35

So that's all synovitis.

59:37

If you give contrast, all this will enhance.

59:39

So an example of rheumatoid arthritis, other causes of, so,

59:44

uh, unexplained tenno synovitis at the level

59:46

of the wrist hand.

59:48

Um, think of, think of rheumatoid arthritis.

59:53

I think we're time is up. So we'll stop here.

59:57

Any questions, anything specific that y'all wanna ask?

60:08

That was excellent. Thank you very much for that.

60:10

Um, very valuable.

60:14

Thank you. Thank you.

60:19

Thank you. Also. Good time, Charlie. Yep.

60:23

Thank you, Julie. Really, I, I love the way you,

60:26

Thank you very much.

60:27

Some of the videos that explain this anatomy

60:31

in the infinite detail, you sort of get lost in it,

60:33

but I felt that you were able

60:34

to describe those posterior corners very simply

60:37

and, you know, you know, accurate, straightforward manner,

60:39

it'll make it much easier to, um, master those areas.

60:44

Oh, I appreciate that. Thank you so much. You

60:46

Mentioned some PDF handouts at one point.

60:49

Is that something that I've missed that I should have or,

60:52

Uh, I, uh, that y'all can check

60:55

with the course coordinators,

60:56

but, uh, this thing, I'll show you where it is.

60:59

Uh,

61:02

Has anyone else seen them?

61:05

No, but I totally concur with what you were saying, Julie,

61:10

and that these sessions, um, it's, there's, oh, I think I,

61:14

there's a huge amount of, uh, information,

61:16

Uh, but there are these standardized reports, uh,

61:21

where they explain you what the findings are

61:23

and there is a, oh, yes,

61:25

Yeah, you can See Oh yeah, we do. We have those. Yep.

61:28

Yeah, this is what I was talking about.

61:29

So in this, yeah,

61:30

there is a little description on the cases too.

61:33

Uh, uh, and I think I spoken, uh, with,

61:36

when we were discussing the case of Butler, uh, uh,

61:40

instability and, uh, trochlear dysplasia.

61:43

So the, the type butler morphology

61:46

and trochlear morphology,

61:48

different types are explained in this PDF.

61:51

Thank you. Yep. Yep. You're welcome.