(light rock music)
- Most anterior cruciate ligament tears
are acute, traumatic injury,
so the symptoms occur with a sporting event,
or an accident, and the symptoms are
acute pain, swelling, discomfort,
inability to ambulate or walk.
The most common history a patient gives
with an anterior cruciate ligament tear
is participating in a cutting or twisting sport.
They plant their foot.
"I felt my knee twist and pop,
"and I was unable to continue playing basketball."
However, the symptoms are variable.
There are patients that tear
their anterior cruciate ligament.
They can continue to play four quarters of a football game,
or continue to ski all day.
However, that is rare.
The amount of swelling or pain
usually precludes the athlete
from continuing in their sport.
Darla is an elite level martial art athlete
who actually injured her anterior cruciate ligament
less than 24 hours ago.
This is what an acute anterior cruciate ligament tear
looks like and what you see is a normal left knee
that's straight on the bed without swelling.
The right knee is puffy.
As I ballot the knee it's filled with blood.
She has 40 or 50 cc of blood in the knee.
You can barely make out the landmarks of her patella.
She can bend the knee up to 70 degrees
before she begins to have pain.
Like a water balloon, it won't bend further.
The classic test to determine
anterior cruciate ligament integrity
is called the drawer test.
Resting over my knee in a position of comfort,
I apply a posterior force,
and one could see the knee come forward like a drawer.
It's like a drawer in a dresser.
She tore her medial collateral ligament,
which attaches the femur to the tibia right here,
which is the ligament that connects
the femur bone to the shin bone,
and it's disrupted in its mid-substance.
So she has a terrible triad:
an ACL tear, a medial meniscal tear,
and a medial collateral ligament,
which will heal on its own.
The meniscus will not.
Many patients will ask, will their knee ever be normal?
What's the success rate of an
anterior cruciate ligament tear.
The problem is, is no anterior cruciate ligament tears
are identical.
The prognosis is often predicted
by the collateral damage.
What other structures of the knee were damaged?
Fortunately, when you tear your ACL,
everybody focuses on the ACL.
It's the dramatic injury.
"I tore the ACL."
Frankly, as orthopedic surgeons,
we don't worry about the ACL too much.
We can give you a new one.
We actually replace the anterior cruciate ligament.
We don't reconstruct it.
We don't tie it together.
We have to give you a new ligament.
If you tear it again, we can give you a second ligament,
or a third ligament, although that's not desirable.
But what really predicts the future
of an anterior cruciate ligament tear
is what other structures you tore,
like the meniscus, the little shock absorbers in the knee.
We are not as readily able to reproduce
or replace the meniscus.
So if you damage your meniscus
and part of it has to be removed,
that's removed permanently, and increases your risk
of arthritis and failure of your
anterior cruciate ligament.
So the factors are not only the
anterior cruciate ligament tear,
but how much associated damage you did
to the lining cartilage, or the meniscal cartilage
in the knee.
The posterior cruciate ligament is the other
robust, strong ligament connecting
the thigh bone, or the femur,
to the proximal tibia or the shin bone.
It's easily seen as this black,
cord-like rope structure in continuity
from the femur to the tibia.
Contrast that to the torn, or the pathologic,
anterior cruciate ligament, which can be seen
as a black, thick cord structure,
and then it tapers off to a gray area,
and then nothing on the femoral side.
This is the tear, like a black cord that has retracted.
It is not in continuity,
unlike the posterior cruciate ligament
that we initially saw.
(light rock music)