0:00

Let's move on now and talk about the third group,

0:03

which is the syndesmotic ligament disc complex.

0:07

One of the major tendons is the anterior tibial fibular

0:10

ligament, typically extending from the anterior border

0:14

of the lateral Aus and

0:16

and connecting to the anterior tubercle of the distal tibia.

0:21

The fibers, as we look at 'em, are oriented upward,

0:25

okay, and medially.

0:27

Alright. This is the classic thing.

0:29

When you look at this, there often are more than one band

0:34

or bundle of tissues.

0:36

Here I'm showing you two,

0:38

and if you look at this, you can see those two uh, bands

0:43

representing portions of the anter tibial fibular ligament.

0:48

Now, there is a third ligament that may be nearby.

0:51

Some people regard it as an accessory to the other two

0:56

bands of tissue, and this is known as Bassett ligament.

1:00

Here's an example of what it looks like

1:03

extending along the medial clear space over the

1:06

top of the Tali.

1:08

Okay? As you can see here, to the medial aspect

1:12

of the tibia, enlargement of this particular band can lead

1:17

to impingement along the antral lateral aspect

1:21

of the angle.

1:23

The second component

1:25

of the syndesmotic ligamentous complex is the posterior

1:28

tibial fibular ligament extending

1:31

between the posterior surfaces of the tibia and fibula.

1:35

When we did cadaver studies on this ligament shown here,

1:39

we often found it was branching, particularly laterally

1:44

with a couple of attachments to the fibula.

1:48

Okay, you can see then classic appearance

1:51

of the posterior tibial fibular ligament typically seen on a

1:56

single axial image.

1:59

I wanna now call your attention to the fibular shape.

2:02

At the level of the lateral syndesmotic ligaments,

2:06

the high lateral ligaments, you do not have that

2:09

concave aspect to the medial aspect of the fibula.

2:14

The fibular shape looks more like this.

2:17

So when you see this shape, you're in the area of the high

2:22

lateral ankle ligaments, the syndesmotic ligaments.

2:25

To complete our story of the syndesmotic ligament,

2:28

this complex here is the third ligament known

2:32

as the intra inferior transverse tibio fbri ligament.

2:37

It is a menis like structure.

2:40

It hangs down and covers part of the posterior surface

2:44

of the Alis.

2:46

Alright, and then the final

2:48

syndesmotic ligament is the interosseous ligament,

2:52

which extends between the medial surface

2:55

of the fibula upward, along the lateral surface

2:58

Of the distal tibia.

3:01

Here's the syndesmotic recess I spoke about earlier

3:04

of the ankle joint.

3:06

This forms the roof or vault of that recess.

3:13

So let's summarize what I've said about these

3:15

lateral ligaments.

3:16

We have two sets of them, one higher,

3:21

that is the synsonic ligaments.

3:25

Here I'm showing you in a cadaver what the posterior

3:29

tibial fibular ligament looks like.

3:31

Note the shape of the fibula at this particular level.

3:35

Here's what it looks like.

3:37

Let's go a little bit lower

3:39

and look at the low lateral ligaments.

3:41

Note the shape of the fibula here. Concave medial margin.

3:46

Hence, we're in the area of the posterior

3:49

talo fibular ligaments.