0:00

Now I also wanted to illustrate this particular portion

0:05

of the collateral ligaments of the wrist.

0:07

You know, we have a radial collateral ligament

0:10

and an ulnar collateral ligament

0:12

and in the wrist as opposed to other joints like the elbow

0:15

and knee, the collateral ligaments are

0:17

not quite as important.

0:20

The ulnar collateral ligament probably has little function.

0:23

It's only the proximal aspect

0:25

of the radio collateral ligament.

0:27

This the radio scaphoid portion of it that has significance

0:32

'cause it stabilizes the scaphoid.

0:34

Alright, this is what it looks like.

0:36

You can see some pictures of

0:38

what it would look like in the axial sagittal

0:41

and coronal planes.

0:45

Now we move to the dorsal aspect.

0:47

The good news is the anatomy is not quite so complex.

0:52

We'll start in the deep aspect.

0:56

We have now the dorsal portions of the scap lunate

1:01

and luno triquetral interosseous ligaments.

1:05

And once again we do have dorsal intercarpal ligaments

1:09

or inter in the distal row shown here there is a triangular

1:15

ligament that is very important.

1:17

We'll be talking briefly about it in this lecture.

1:20

It's the scap trapezial

1:22

or scap trapezial trapezoid ligament.

1:26

'cause it may extend that far into uh,

1:29

to reach the trapezoid and it is important.

1:32

And then there is a dorsal intercarpal ligament

1:35

that we will be talking about later.

1:38

It goes from scaphoid to trium,

1:41

so it's sometimes called the dorsal

1:43

scavo triquetral ligament.

1:46

To that we have to add one extrinsic ligament known

1:50

as the radio triquetral or radio luno triquetral

1:55

because it has generally as an attachment to the lunate.

1:59

Now, in this particular drawing I show you separate

2:02

footprints of the dorsal intercarpal ligament

2:05

and this ligament, but sometimes they share a footprint.

2:10

This is what these ligaments look like here.

2:13

I found them in a cadaver.

2:15

So here is the dorsal radio triquetral ligament.

2:18

This is that dorsal intercarpal ligament.

2:21

And here they seem to have a common attachment

2:25

on the trium.

2:26

You can kind of see them, not a beautiful MR image.

2:29

On your left, we look at the dorsal intercarpal ligament.

2:34

This is kind of what it looks like.

2:35

I'm gonna show you images of it later.

2:38

Both normal and abnormal. So those are the two ligaments.

2:43

And if they share a footprint, it should not be surprising

2:46

that you may get avulsion fractures

2:48

as shown here on your left in these MR images

2:52

with a white arrow pointing to the UL bone fragment related

2:56

to either one or both of

2:58

These ligaments.

3:00

Now there's some people who believe in fact, the cause

3:02

of evulsion fractures of the trium may include also contact

3:07

with the ulnar styloid during extreme dorsi flexion

3:12

of the wrist because you may see in accompanying ulnar

3:16

styloid fracture.