0:00

There's a, a 21-year-old, uh, gentleman status post MBA.

0:04

In actuality, he was a pedestrian versus auto type of MBA,

0:08

uh, so he was the one walking

0:09

and got struck by a car, physical exam.

0:14

And I'm poking fun at my, the ER colleagues here, uh,

0:18

and I'm married to one, so she's not very good

0:21

with her knee exam either.

0:23

Um, and so they recorded that there was no laxity on exam,

0:27

but they still consulted, uh, ortho

0:29

because the patient was having knee pain, um, or a pati.

0:34

Uh, the patient did have a tibial plateau fracture on

0:36

imaging, but their exam found vagus valgus laxity

0:41

and a PO posterior jaw sign.

0:44

So they elected to follow up the patient as an outpatient

0:49

and did an MRI one month later.

0:52

So I'll just pull up the images.

0:58

The, um, radiographs, uh, not too revealing,

1:04

uh, maybe a, a small effusion

1:06

that we can see on the lateral view.

1:07

There's a question of something in the joint space here,

1:10

a little calcific density.

1:12

Who knows if that's a little chondral body,

1:14

maybe in a little bit of irregularity

1:16

of the lateral tibial spine.

1:19

And, uh, again, if you look at CT

1:22

and uh, radiographs, you may want to start

1:25

to hone your search pattern on the soft tissues.

1:27

And maybe if I window it here,

1:29

you may appreciate some soft tissue swelling along the

1:32

medial joint line, but of course that's very difficult.

1:35

So we'll go ahead

1:36

and, um, move on to the next imaging study, which was

1:41

actually at the time of the er, a CT exam.

1:45

So I'll just show you that very briefly.

1:47

So we do see some little tiny bone fragments here along the

1:51

lateral tibial spine.

1:52

This patient had a subtle fracture

1:54

of the lateral tibial plateau that was difficult

1:57

to appreciate on the radiographs.

2:01

And maybe if I can convince you, you can hallucinate.

2:06

Let me window this more for the soft tissues.

2:09

An abnormality of the medial collateral ligament here.

2:12

Normally, as we know, the medial collateral ligament should

2:14

pretty much hug the osseous boundaries of the distal femur

2:18

and the proximal tibia, just like

2:21

that fibular collateral ligament case

2:22

where we saw a retracted superiorly

2:25

retracted and redundant ligament.

2:26

There's some density structure here

2:29

that looks wavy and redundant.

2:32

So that's a sneak peek into what we are going

2:35

to see on the subsequent MRI.

2:39

So we hear we have telltale signs

2:42

of a valgus injury on the MRI.

2:45

We can see the impaction injuries along the lateral

2:48

femoral tibial compartment.

2:49

We see some bone contusions as a lateral femoral condyle,

2:52

this focal articular surface step off of the central aspect

2:56

of the lateral tibial plateau.

2:58

You can even see there's a little bit

2:59

of control irregularity

3:01

where the fracture probably propagated through

3:03

that lateral tibial plateau.

3:06

On the medial side, we can see

3:09

that there's a tensile sided injury

3:11

to the medial supporting structures.

3:13

And as you remember on that ct, we were able

3:16

to visualize the superficial fibers

3:19

of the medial collateral ligament.

3:20

So that was, that was what represented those wavy fibers

3:24

that we're seeing on the coronal ct.

3:27

We can see also that there is disruption

3:30

of the deep portions of the media collateral ligament,

3:33

namely the deep medial meniscal femoral portion

3:36

of that deep ligament.

3:38

The meniscul tibial ligament is not as nice

3:40

and thin as we've seen in those other cases.

3:43

So this actually represents some degree of sprain of

3:46

that deep meniscul tibial ligament.

3:49

As we move more posteriorly, ideally

3:52

we should also see the fibers

3:53

of the posterior oblique ligament, usually thin, black,

3:58

low signal intensity fibers.

3:59

And we see here that this is indeed thickened along the more

4:03

posterior aspect of the needle femoral epicondyle.

4:07

So here's what it looks like on axial images.

4:09

This is the MCL that is thickened

4:11

and irregular in appearance.

4:13

And the posterior bleak ligament should sort

4:16

of look like a low signal intensity structure wrapping all

4:19

the way around the medial femoral condyle.

4:22

And its femoral attachment lives just

4:24

behind the medial epicondyle where

4:26

that medial collateral ligament attaches.

4:28

And you can see here that this two is thickened

4:31

and, um, a descent appearance reflecting partial tearing

4:34

of the posterior O ligament.

4:37

Now, this patient didn't have a patella dislocation,

4:42

but you can see that there is a concomitant injury

4:46

to the media patella femoral ligament similar

4:48

to the last case, the, the femoral, excuse me,

4:51

the patella attachment and the mid portion looked relatively

4:54

okay, but as we make our way over to the medial epicon,

4:57

we can just see that the ligament basically peters out is

5:00

attenuated, and we don't see it attached anywhere to the MCL

5:04

or to the medial, uh, femur.

5:08

There's a little bit of chondral fissuring in

5:10

the patello femoral compartment.

5:11

That's not the main take home point of this case.

5:15

But remember, the patient did have a, um, a, uh,

5:20

posterior jaw sign on exam.

5:24

So you can see that there's thickening

5:27

of the mid proximal portions

5:29

of the posterior cruciate ligament

5:31

with intra ligamentous edema.

5:33

Now remember this MRI is performed about one month

5:36

after the initial injury.

5:38

So it could be that some

5:39

of the acute edema had we imaged the patient immediately

5:42

after the injury has resolved

5:44

and there's, um,

5:45

the ligament is starting to remodel and heal.

5:47

So we don't see any, uh,

5:50

what looks like a complete disruption.

5:52

But the PCL is kind of tricky

5:53

because it can undergoing,

5:55

it can undergo a stretching deformation

5:57

and still be significantly lax at exam.

6:00

So this is a injury to the posterior cruciate ligament.

6:03

If I were to grade this, I would still probably call it a

6:06

high grade given the degree

6:07

of intra ligamentous signal abnormality.

6:10

If we look at the rest of the intercondylar notch,

6:12

the anterior cruciate ligament is actually

6:14

relatively, uh, intact.

6:16

We can see fibers of both the ant medial bundle

6:19

and the more s strided poster lateral bundle,

6:21

often having areas

6:22

of increased signal within the interstices

6:25

of those ligament fibers.

6:28

One thing I wanted to mention about the distal MCL,

6:31

and this is something that has uh,

6:33

been talked about repeatedly in the last few lectures,

6:36

is when you have a distal MCL tear, you always wanna look

6:41

for the distal attachment site.

6:44

And as we follow this MCL inferiorly,

6:46

we'll see the pez answering tendons.

6:48

And remember, goose's foot sartorius GLIs semi tendinosis,

6:53

we'll see that, uh, the MCL indeed is superficial

6:57

to the, uh, pez anine tendons.

7:00

So this is that, uh, entner lesion

7:02

that we've been seeing over

7:03

and over in, uh, our lectures today.

7:08

So if I go back to this slide, so the

7:11

superficial MCL ideally should reside deep

7:15

to these pez tendons.

7:17

And here's what it looks like on MR.

7:19

I normally situated deep to the IES forus

7:22

and semi tendinosis.

7:23

And here in our case, the torn distal fibers

7:28

of the MCL are superficial to these tendons.

7:31

And I overheard some of the discussion yesterday, um,

7:34

whether or not, uh, these are repaired.

7:37

And, and Dr. Chang said, like in the ideal world, yes,

7:40

these should be repaired

7:41

because these have a, theoretically a poor healing potential

7:45

if that superficial MCL is not restored

7:47

to what's normal anatomic location.

7:50

A lot of times, um, these injuries are overseen

7:54

and, uh, are not repaired.

7:56

So, uh, this patient, uh, didn't, uh, have any surgery.

8:00

They elected for non-operative management,

8:02

but at six months later, they still had grade two to three,

8:05

um, valgus laxity.

8:07

So they still had laxity along their MCL

8:10

and still had a grade two PCL exam, uh, at least moderate,

8:14

uh, instability or laxity of that PCL.

8:19

So, uh, the option was given, uh, to allow the patient

8:22

to continue their activity with knee bracing

8:24

and they continue to have symptomatic instability

8:27

to undergo a formal medial collateral

8:30

ligament in construction.

8:32

So I thought I'd share with you this article

8:34

because, um, this shows that, uh,

8:37

medial patello femoral ligament injuries are actually fairly

8:39

common in the setting of patients with MCL injuries.

8:43

And, um, I'm glad that they, uh, decided to investigate this

8:46

'cause I saw this quite a bit

8:47

and I never knew what to do

8:49

with the concomitant MPFL injuries in the setting of

8:52

what is more or less an MCL

8:54

Injury. And

8:55

they found long-term these patients didn't have any

8:59

chronic patella femoral sequelae,

9:01

meaning they didn't have any subsequent lateral patella

9:04

dislocation or patella instability symptoms.

9:07

But I think it's still worthwhile, uh, reporting.