0:00

We're gonna move on now to the third portion,

0:03

the posterior portion where the anatomy

0:06

is a little bit more complicated.

0:08

So the postal medial corner does have complicated anatomy,

0:13

not like the postal lateral corner where the anatomy,

0:16

as you'll hear about, is far more complicated.

0:20

The major structure of the posterior portion

0:23

of the medial supporting structures is the

0:26

posterior oly ligament.

0:28

Its femoral footprint shown by the yellow arrow.

0:32

It consists, as you will see, of three components

0:35

that have a broad femoral attachment

0:37

that is located about eight millimeters distal

0:40

and six millimeters posterior to the adductor tubercle.

0:45

Okay? And additionally, 1.5 millimeters distal

0:49

and three millimeters anterior to the gastroc tubercle.

0:54

So this is the approximate location,

0:57

but there are three components

0:59

and I wanted to show you what they look like.

1:01

We're looking at a medial view at the top right

1:04

and a posterior view at the top, at the bottom right,

1:08

and I have color coordinated these.

1:10

The superficial arm is shown by the yellow arrow.

1:14

It is the anterior structure. It is thin.

1:19

It courses medial to the anterior arm

1:22

of the semimembranosus bustle, uh, mu muscle, excuse me,

1:26

the second part shown by the orange arrows,

1:30

the thick thickest portion.

1:33

This is the tibial or central arm.

1:37

I talked about it briefly the other day when I was talking

1:39

about problems that occur in the meniscus that may lead

1:43

to corner like meniscal failure

1:45

because this particular arm, as it extends distally deep

1:49

to the anterior arm of the emus muscle, it can

1:54

reinforce not only the deep medial capsule ligament,

1:58

but can attach to the medial meniscus.

2:01

So a tug lesion on this arm could produce

2:05

meniscal abnormalities.

2:07

The third component shown in green

2:11

is the capsular arm.

2:12

This two is thin.

2:14

It's the most posterior portion of the posterior OBL liga.

2:19

Okay. Now, as you look at these three components,

2:23

the anterior one is more vertically oriented,

2:25

and the other ones are o obliquely oriented,

2:28

running backward from the femur toward the tibia.

2:33

Um, we, Eric showed you some beautiful cases, uh, yesterday

2:37

of injuries to portions of the medial supporting structure.

2:41

And in some of them you could see this obliquely oriented

2:45

edema outlining portions of that posterior O ligament.

2:51

The other structure that I would, uh,

2:53

mention in the posterior portion

2:55

of the medial supporting structures is the

2:57

oblique popliteal.

3:00

This is an interesting

3:01

and markedly obliquely oriented structure running from a low

3:05

medial to a high lateral, uh, region.

3:09

As you can see by the orange like arrows in the picture,

3:14

it's a tendonous expansion in the postal medial

3:17

aspect of the knee.

3:19

It arises from the semimembranosus muscle tendon complex,

3:24

as well as one of the arms of the posteriorly ligament,

3:27

and it runs laterally

3:29

and upward becoming intimate

3:31

with a lateral gastroc anemia muscle,

3:34

and the plant terrace muscle.

3:36

It's also intimate with the arcuate ligament labeled

3:40

Al in this particular drawing.

3:45

The final structure that I would emphasize, uh,

3:48

in the posterior third

3:50

of the medial supporting structures is the semimembranosus

3:54

tendon complex.

3:55

And there are five components to them.

3:58

I've listed them here.

3:59

You've heard about some of them earlier in this course.

4:03

You've heard about the tibial or anterior arm.

4:06

You've heard about the direct arm in both in my lectures

4:10

and in Eric's lectures.

4:12

This is a sagal image done in an anatomy study we did a long

4:16

time ago, showing you that one of the arms, this is the

4:21

anterior arm of the semi menos,

4:23

and as it goes further down, as shown in the specimen,

4:27

it courses further anteriorly deep

4:30

to the tibial collateral ligament.

4:32

All right, so that is one of the important arms.