Interactive Transcript
0:00
Now, we said earlier that this vertical longitudinal
0:05
tear is one type of up and down tear.
0:08
There's another kind of up and down
0:09
tear that we should talk about,
0:12
and that is one that starts in the inner third,
0:16
and instead of going
0:19
up and down,
0:21
that's parallel to the capsule.
0:24
In other words, that's parallel to the capsule,
0:27
which we'll imagine is here in red.
0:30
That has some blood in it.
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It is perpendicular to the capsule,
0:35
kind of like the spokes on a wheel,
0:39
right.
0:41
The spokes on the wheel are perpendicular
0:43
to the outer part of this circle,
0:48
kind of like the wheels on the bus
0:49
go round and round. Right.
0:51
So what does that look like?
0:53
Well, here's the spoke on the wheel right here.
0:55
It's coming right at you.
0:56
It's coming at you.
0:58
Sometimes it makes a little v.
1:01
That's a radial tear,
1:03
and that goes into the screen.
1:04
That also goes up and down.
1:06
It's just in a different axis.
1:08
Now,
1:09
we're interested in this tear because this
1:13
tear can get a little bit nasty.
1:16
Well, how come?
1:19
Because it's in an area that doesn't heal.
1:21
Remember, we have outer third, red red zone,
1:24
middle third, red white zone, inner third,
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white white zone.
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The white white zone has no vascularity,
1:31
doesn't heal.
1:32
Okay, so we have a little tear there.
1:35
When do we mess with it?
1:36
When it's symptomatic. But what kind of symptoms?
1:39
Pain, maybe not because pain alone,
1:43
maybe it breaks off. Maybe it's scars.
1:45
Maybe the pain goes away.
1:46
But if it's pain and clicking or pain and locking
1:49
or pain and progressive arthritis,
1:52
then it has to be addressed.
1:53
Now, in the orthopedic literature,
1:55
they say that if the tear has a depth of greater
2:01
than six to 8, are more likely to become unstable,
2:07
to propagate,
2:09
and even to lead to consequences like
2:12
fragmentation, locking, and chondromylation.
2:14
But I think we've gotten a little more liberal as
2:17
time has gone on and less aggressive in trying to
2:20
resect these tears because there's no sewing them.
2:23
You just go in with a claw,
2:24
and you just claw them out of there,
2:25
which is kind of ugly.
2:28
So what do we mean by depth?
2:31
Depth is the measurement from here,
2:34
the inner edge, to the outer edge.
2:37
So depth goes this way.
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Remember,
2:40
length is completely different for
2:41
the longitudinal vertical tear.
2:44
For the radial vertical tear,
2:47
we're more interested in this character.
2:50
Now,
2:50
we also have gapping the side to side dimensions
2:54
so the tears can get a little wide.
2:56
And the more gap they are,
2:58
the more troublesome they are.
2:59
So depth is important.
3:01
The measurement from here to here,
3:03
greater than six to 8 mm,
3:05
but also the side to side dimension,
3:09
because gapping can lead to instability.
3:13
Instability of what? Instability of the meniscus.
3:18
So where might we see a problematic area of
3:22
gapping back here, near the meniscus root.
3:27
Remember, we have a posterior horn posture, third,
3:30
a body middle third,
3:32
an anterior horn anterior third.
3:35
To keep it simple,
3:36
we also have,
3:38
in the deepest attachment of the meniscus,
3:41
the meniscus root, in the back and in the front.
3:44
And although we haven't drawn them in,
3:46
there are ligaments.
3:47
Don't confuse the meniscus root,
3:49
which is meniscus,
3:50
with the meniscus root ligament.
3:53
You can tear the meniscus from its root,
3:56
you can tear the ligament from the bone.
3:59
Now, they both have the same consequence,
4:01
but what happens if you have one of these
4:03
radial tears and it keeps going back,
4:07
to quote Chris Berman,
4:09
and it keeps going back and boom,
4:12
it goes to the outer surface.
4:14
Now we got a problem, right?
4:16
The meniscus isn't anchored to itself anymore.
4:20
Doesn't matter where the ligament is still there.
4:23
This is not attached to that.
4:25
And so they spread apart,
4:29
and the meniscus starts to float this way
4:33
out of the edge of the femur and the tibia.
4:37
And now you essentially have a meniscus
4:39
that extrudes itself.
4:40
So these very large radial root
4:44
tears are problematic.
4:46
The little ones, we leave all of those alone.
4:49
We hardly ever touch the root.
4:52
Radial tears that don't go all the way through,
4:55
even the ones that almost go all the way through,
4:58
we don't touch.
4:59
But the ones that clearly go all the way from
5:01
the inner third to the outer third,
5:03
the meniscus is starting to gap and
5:04
separate those we got to go after.
5:08
So we've learned about two very important
5:12
vertically oriented tears today.
5:14
The one that's longitudinal and parallel to the
5:17
outer portion of the meniscus and the one that's
5:20
perpendicular to the outer arc of the meniscus,
5:25
the one that's parallel,
5:27
is less problematic because it's in the red,
5:29
red zone.
5:31
The one that is perpendicular is problematic.
5:34
Now, if this radial tear were to arc,
5:36
if it were to do something like, say this,
5:40
we would call it a flap tear.
5:43
See,
5:43
radial tears are straighter
5:46
if it were to arc and it were to get a little
5:48
bit wider and a little bit longer.
5:51
Now we're into a parrot beak tear,
5:55
which happens to, like, the body horn junctions.
6:00
Let's draw another meniscus for a moment,
6:04
just so we can demonstrate one
6:05
other thing for completeness.
6:07
I realize my meniscus is a little bit thin here,
6:11
but I think you can see it.
6:13
Actually,
6:13
I'm going to make it thicker because I know
6:16
I'm going to get reprimanded if I don't.
6:18
Let's make a thicker meniscus.
6:21
Erase this one.
6:23
Give you
6:25
a little more visual
6:29
stimulation here. Oh, wow,
6:31
that's a really thick one.
6:33
Yeah.
6:33
This is for all of us out there
6:35
that are over age 60.
6:37
So here's a big, fat meniscus.
6:41
Okay, now let's make it thinner.
6:44
Let's make our line thinner,
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and let's change the color.
6:49
And now let's assume we have a longitudinal
6:52
tear and it's in the middle third.
6:57
It would be a vertical longitudinal
6:59
tear in the middle third.
7:01
But if that vertical longitudinal tear starts to
7:04
gap and get wider and wider and wider and wider,
7:07
and all of a sudden this portion of
7:09
the meniscus starts to go inwards.
7:12
Now we have ourselves a bucket handle tear.
7:17
So a bucket handle tear really starts
7:19
out as a vertical tear,
7:20
usually in the center of the meniscus,
7:22
and that will be a story for another day.
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