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Knee injury
This is a coronal proton
density weighted image
of the knee. Do you
think we are in the front
or back of the knee?
We are in the back,
you see the fibula
instead of the patella.
Fibula
Which hamstring
tendon attaches to the
fibula posteriorly?
This is the biceps
femoris and here you
see the muscle.
What are these low
signal shock absorbers
between the femur and
the tibia?
These are the menisci
What is this low signal
ligament coming off
the femur? You do not
see the fibular
attachment of this
ligament.
This is the lateral
collateral ligament
What is this ligament
coming off the medial
femur and attaching
onto the tibia?
This is the medial
collateral ligament,
note the attachment
to the medial
meniscus.
On this image note the
femoral attachments to
the anterior (black)
and posterior (white)
cruciate ligaments.
Can you see the tibial
attachment of the
anterior cruciate
ligament on this
image?
Again identify the
medial collateral
ligament and its
meniscal attachment
(arrow).
This image show
disruption of the
medial collateral
ligament from a
valgus injury.
Note the fiber
disruption, black
ligament gone, at the
femoral attachment
Can you identify the
iliotibial band and its
tibial attachment?
Why is the cortical bone
so black (arrows) and
the medullary bone so
bright (circle) on this
imaging sequence?
Remember that
cortical bone is
densely packed and
gives almost no signal
on MRI and medullary
bone has fat and
marrow producing
elements that make it
bright on T1 and
proton density images.
What is the name of
this anterior bony
structure?
This is the patella
This is a sagittal proton
density weighted MRI
image. Are we medial
or lateral?
Lateral look at the
fibula.
What the these 2
structures attaching to
the fibula?
Lateral collateral
ligament
Biceps femoris
tendon
What is this low signal
structure between the
femur and the tibia?
This is the lateral
meniscus.
What is this grey signal
material coating the
tibia and the femur on
both sides of the
meniscus?
This is the articular
cartilage. Is it the
same type of cartilage
that makes up the
menisci?
No. Hyaline cartilage
is articular and the
menisci are made up
of fibrocartilage. Note
the signal differences
between these
cartilage types, likely
related to their water
content.
As we approach the
mid knee what are
these anterior tendons
we see.
Quadraceps tendon
Patellar tendon
What is the bone
between them?
This is the patella, you
largest sesimoid bone.
We are now at the
mid knee. What is
this ligament?
This is a normal
anterior cruciate
ligament.
This is a torn ACL
on a fat suppressed
image. This is why
this image is so
black. Note the high
signal (white) where
the ACL is disrupted.
Do you see the
posterior cruciate
ligament on this
image?
Look at the medial
meniscus on this
sagittal image in the
medial compartment.
Does it look normal?
No. It is torn, do you
see the tear?
The tear is where you
see high signal
extending into the
meniscus.