00:00
You. We're going to talk about the knees.
00:02
Knees are an interesting joint,
part of the lower extremity,
and difficult to manipulate
because you don't have
lots of tools in your armamentarium.
00:13
But what you do have is a lot
of patients who have problems.
00:16
So understanding the biomechanics,
understanding the history,
and witnessing and predicting
what's going to happen to the knee
is often all you can do.
00:27
So we're going to talk about
the knee itself, what makes it up
and what we can do and
where we can focus.
00:34
So, starting with the anatomy.
The knee is an interesting joint.
00:38
It's basically the femur with two grooves
with the patella in between,
with a whole bunch
of articulations
held together by ligaments,
bursa, and muscles.
00:48
When you look at the
articulation, it's a hinge joint.
00:51
You have the tibiofemoral articulation,
patellofemoral articulation,
and the tibiofibular articulation.
01:02
And the tibia and the fibula
are interesting bones.
01:05
Tibia is the flat one anteriorly,
and the fibula is the lateral bone
that we used to say was only
for muscular attachment.
01:15
We're not sure fully what
the fibula's role is,
but we do know it does help
with some of the motion,
some of the gliding of the knee,
and it's important.
01:26
We're going to talk a lot about the
menisci, the medial and lateral meniscai.
01:31
Those are the shock absorbers of the knee.
01:33
Those are the pads that
displace the energy
so that when you're walking,
your pain is not
going to be pinched,
your pressure is not
going to be focused.
01:43
It's going to be
splayed, displaced,
and allow you to use your whole
knee and your whole foot area.
01:49
And we'll discuss the bursa,
the bursae little pockets
that have synovial fluid in it
that will swell with overuse and
give you a sense of what's going on.
01:59
So take a look at the picture
here, get a sense of the anatomy,
use your own body as a model
and work on
understanding the bones,
the muscles and the ligaments
that are going to explain where
you're going to have problems.
02:13
Again, the bones are easy.
02:16
You have the femur superiorly,
you have the tibia,
which is the flat bone,
and the patella,
which is a sesamoid bone.
02:25
It's a bone within the ligament.
02:26
And the fibula, which comes down
on the lateral aspect of the leg.
02:32
The muscles and
fascia are there.
02:35
The quadriceps are the ones you're
going to be focusing on the most,
the ones that are going
to extend the knee
and the quadriceps, vastus, medialis,
lateralis, and intermedius,
as well as the rectus femoris.
02:52
So the muscle and
fascia are important.
02:55
You have both flexors and extensors.
You have the quadriceps
and the hamstrings in the back
causing the flexion.
03:03
And then we'll talk about the ligaments,
the anterior cruciate and
posterior cruciate ligaments
that keep the knee stable,
and the medial collateral
and lateral collateral
that also keep the knee in place.
03:16
So those are the four ligaments
we'll talk about that are often injured
and need to be paid attention to
and often tested for.
03:23
In terms of the joints
within the articular capsule,
you have the tibiofemoral joint
and the patellofemoral joint
that are going to help
with the hinge motion.
03:35
And you have the superior fibulotibial
joint and the knee as well.
03:40
It is a modified hinge joint.
03:43
There is flexion and
extension of the knee.
03:45
When there is instability,
you're going to have more
motion to the sides,
which we try and restrict.
03:52
There's some rotation possible,
as you notice when you go side to side.
03:57
You'll notice you do get some
rotation of the knee,
and you're going to have more
rotation when it's flexed,
which is also when you're
more likely to injure the knee
because of the laxness of the muscles
and the loss of protection.
04:11
The meniscai again allows
for stability of the joint.
04:17
They deepen the tibial plateau.
04:19
They give you a substance
that will displace energy
and force when you're walking.
04:26
It will allow for a smoothness of
functioning by decreasing friction.
04:30
It increases the contact area
for the femur and absorbs shock.
04:36
When we talk about the
medial and lateral menisci.
04:39
We also note how much vascularity
it has in each portion,
separating into the anterior, middle,
and posterior portions of the menisci.
04:49
And the more blood supply you have,
the more likely the menisci
can heal on their own.
04:57
If you don't have much blood
supply and you do injure it,
it's going to be a tough injury,
and it's not going to be something
that's going to heal quickly
or easily on its own.
05:07
And often surgical
intervention is suggested.
05:10
If you do remove the menisci
because of injury or trauma,
it doesn't stop you from
having normal function,
but it does limit the amount of
time you can have normal function
and increases the likelihood or
possibility of having swelling
or other abnormalities
occur from use of the knees.
05:30
It will also lead to an increased
wear and tear on the articular surfaces
and increase the risk of
developing degenerative
joint disease later on in life.
05:40
So the patella is the largest
sesamoid bone in the body.
05:44
It floats in the quadriceps tendon,
and the quadriceps are the four
muscles that will extend the knee.
05:54
The patella will slide vertically along
the ridges of the femoral condyles
and it does have an articulation.
So it's a fulcrum, it helps with motion,
it helps with stability,
and it gives you the strength
to move the leg
harder and stronger.
06:13
It does also allow other motions
and patellar moves side to side
and gives you some freedom.
06:20
The ligaments. There are four
ligaments holding the knee together.
06:23
The anterior cruciate ligament,
which will prevent
anterior displacement of the tibia
and prevents
hyperextension of the knee.
06:32
Occasionally you see people who will
extend greater than 180 degrees.
06:36
There is some ligamentous laxity
on occasion and that can occur,
but the anterior cruciate ligament
keeps it strong, keeps it stable
and prevents overextension
and stabilizes the knee.
06:50
The posterior cruciate ligament
will prevent posterior displacement of
the tibia and hyperflexion of the knee.
06:58
The medial collateral are the deep fibers
that are attached to the medial meniscus
and keep the knee stabilized.
07:05
And the lateral collateral does
not attach the lateral meniscus,
but it attaches to the fibula,
so it does bring
the fibula into motion.
07:15
Why are we talking about
ligaments and muscles
in an osteopathic medicine lecture?
Because people will complain of pain,
people have trouble functioning,
and it's important to know when to
use flexion, when to use extension,
and how you use knee motion
to both affect one joint above the hip
and one joint below the ankle.
07:35
So those are important concepts.
07:37
Bursae are the little pockets
with synovial fluid.
07:42
They have serous membranes
that will secrete
a lubricating fluid
that eases motion.
07:49
They're found in locations where
you have friction and motion.
07:53
They swell up with more use,
they shrink up with less use,
and it allows the structures
in the nay to move freely.
08:01
And it's also a warning sign
when you overuse a joint
or misuse a joint.
08:06
If you have an unstable
or a deviated knee,
the bursa in that area will swell up.
08:13
You will also have
increased bony deposition
in areas of greater friction.
08:18
Wolff's Law, where pressure is
going to increase bony formation,
is affected by the bursa.
08:23
The bursa gives you a little bit of leeway
in that you're not always having the bone
on bone friction causing bony growth.
08:32
You're having some bursa, some fluid,
some area of separation.
08:38
When you walk the bursa will also
affect limitations of motion,
and it's important to know
that what's possible.
08:47
When you're walking,
you need to be able to move the knee
about zero to 60 to 70 degrees.
08:52
When you're climbing stairs,
you need to be able to get to 80 degrees
of motion of the knee to get upstairs.
08:59
When you're going downstairs,
you need to get to 90 degrees of motion.
09:05
sitting down, you want to be able to
flex the knee a little bit past 90.
09:10
So, 90 to 95 is usually
going to be comfortable
sitting on a chair
or on a couch.
09:17
In order to tie your shoe,
you need to be able to flex it
to 100 to 110 degrees.
09:23
That's why a lot of people
will lose the ability to tie a shoe
before they lose the ability
to walk up or downstairs
or have trouble sitting.
09:32
And lifting objects often takes
greater flexion up to 120 degrees.
09:40
So you're going to lose the
ability to lift objects comfortably
and you're going to be
off balance, lifting objects,
using other muscles and pulling
the skeleton in other ways
in order to stabilize yourself,
using a wider gait, using your arms
and starting to develop
different centers of gravity.
10:01
So even though this is the knee
that's having the limitation,
it affects the functioning
of the whole body.
10:08
In assessing the knee,
you always look at the tibia and femur
in relation to each other.
10:15
So tibial dysfunctions are
actually pretty common,
tough to treat, and people usually don't
think of this as an osteopathic issue.
10:24
They think of it as an orthopedic
issue and a bony issue.
10:28
The dysfunctions that we treat
osteopathically are typically
distal tibia and distal fibula,
not the proximal.
10:37
A tibial dysfunction can be when you
have the tibia abducted or adducted,
whether it goes
anterior or posterior.
10:45
Again, the tibial
dysfunctions we can treat
are going to be the distal ones,
and it's usually accessed
by sliding the tibia laterally,
pushing it out away from the body
or medially and anteriorly.
11:02
Typically, I push it more laterally
and treat the tibia that way.
11:08
In terms of the
fibular dysfunction,
you can have anterior or
posterior fibular head,
and that's the distal fibular head
close to the ankle,
and it's usually assessed by sliding
the fibula anteriorly or posteriorly.