Transcript tibia - Cloudfront.net

KNEE ANATOMY
RHS Sports Medicine
BONY ANATOMY OF THE KNEE
TIBIA
FIBULA
3
4
FEMUR
PATELLA
2
1
KNEE JOINT LINE
• The joint line of the
knee is where the tibia
and the femur meet.
• PALPATE THE
LATERAL JOINT LINE.
• PALPATE THE
MEDIAL JOINT LINE
•
•PALPATE THE
HEAD OF THE FIBULA
TIBIA
• The tibia is main weight bearing
bone of the lower leg.
• The proximal end of the tibia
is part of the knee joint.
• The top of the tibia is flat and
is called the tibial plateau.
- LABEL TIBIA ON YOUR
WORKSHEET.
- CIRCLE THE TIBIAL PLATEAU
ON YOUR WORKSHEET.
FIBULA
• The fibula is a NON- weight
bearing bone on the lateral
aspect of the lower leg.
• The proximal end of the
fibula is near the knee joint
but is not considered an
actual part of the joint.
- LABEL FIBULA ON YOUR
WORKSHEET.
FEMUR
LABEL THE
FEMUR ON
YOUR
WORKSHEET
• A common name for the
femur is the “thigh bone”.
• The femur is the longest,
largest, strongest bone in
your body.
• When you stand or walk, all
the weight of your upper
body rests on them.
• The femur is part of the
knee joint distally
and the hip joint proximally.
PATELLA
• The common name for the
patella is the “kneecap”.
• The patella is an
irregularly shaped
sesamoid bone.
• The anterior surface is
smooth and rounded.
• The posterior surface is
wedge-shaped.
• It is possible to break your
kneecap!
BONES OF THE KNEE JOINT
?
FEMUR
FEMUR
?
FIBULA
FIBULA
TIBIA
TIBIA
?
PATELLA
PATELLA
?
KNEE MOTIONS
FLEXION EXTENSION:
Bending the knee Straightening the leg
Hamstring Muscles Quadriceps Muscles
KNEE MOTION
• The knee joint is a
hinge joint.
• Flexion and extension
happens between the
femur and the tibial
plateau.
• The patella articulates
with the femoral
groove.
PATELLAR TENDON
The patellar tendon
attaches the patella
to the tibial
tuberosity.
DISTALLY, all
Quadriceps muscles
attach firmly to the
superior edge of the
patella.
KNEE
LIGAMENTS
(ANTERIOR VIEW)
(POSTERIOR VIEW)
• Ligaments run
from bone to
bone. There are 4
main ligaments in
the knee.
• Ligaments HOLD
bones together.
• Ligaments are NOT
involved in moving a
joint!
• They have different
shapes. Some
ligaments are like cords
(lateral). Some are
thin and wide (medial).
KNEE LIGAMENTS – MEDIAL
(MEDIAL
VIEW)
Medial Collateral
Ligament
(MCL)
•Attaches to the femur
and to the tibia.
•2 layers Thick and
flat
Outer = longer
Inner = shorter
Stronger than lateral
ligament and more likely
to be injured
KNEE LIGAMENTS - LATERAL
(ANTERIOR VIEW)
(LATERAL
VIEW)
Lateral Collateral
Ligament
(LCL)
•Attaches to the femur and
the head of the fibula.
•Easily palpated along the
lateral aspect of the knee
when knee is extended.
•Cord-like in shape. Less
likely to be injured
KNEE LIGAMENTS: INTERNAL
ACL
femur
A nterior
C ruciate
L igament
The ACL attaches to the
femur and to the tibia in the
center of the knee joint.
It attaches posteriorly on the
femur but angles forward to
attach at the front of the
tibial plateau.
L
C
L
tibia
M
C
L
KNEE LIGAMENTS: INTERNAL
ACL
Keeps the tibia
from moving
forward on the
femur
(Anterior Translation)
KNEE LIGAMENTS: INTERNAL
PCL
P osterior
C ruciate
L igament
femur
The PCL attaches in the opposite
direction of the ACL - anteriorly on
the femur but angles backward to
attach over the edge and in the
back of the tibia.
It crosses the ACL inside the
knee joint.
tibia
KNEE MUSCLES
QUADRICEPS (4)
Rectus femoris
Underneath(Vastus Intermedius)
Vastus Medialis
Vastus Lateralis
Major Motion:
Extension of the Knee
QUADRICEPS #1
Rectus femoris
•Muscle starts on Pelvis
•Ends at top of Patella
•Crosses two joints
QUADRICEPS #2
Vastus
intermedius
Underneath the
rectus femoris
•Muscle starts along the
lateral edge of the
femur.
•Ends at top of Patella.
•Hidden underneath the
rectus femoris.
Front View
QUADRICEPS #3
Vastus Medialis
•Muscle starts along the
medial edge of the
femur.
•Ends at top of Patella.
•Upper part hidden
under other muscles.
•Can be palpated near
the knee.
Front View
QUADRICEPS #4
Vastus Lateralis
•Muscle starts along the
lateral edge of the
femur
•Ends at top of Patella.
•Upper part hidden under
other muscles.
•Can be palpated near the
knee.
Front View
QUIZ - QUADS
Rectus femoris
(Vastus Intermedius)
Vastus Lateralis
Vastus Medialis
Major Motion:
Extension of the Knee
KNEE MUSCLES
HAMSTRINGS (3)
Biceps femoris
Semitendonosus
Semimembranosus
Major Motion:
Flexion of the Knee
HAMSTRING #1
Biceps femoris
•Muscle has two starting
points:
•Ishial Tuberosity (bone you sit
on) and along back of femur
•Ends at Head of Fibula
•Crosses two joints
HAMSTRING #2
Semitendonosus
•Muscle originates on the
Ishial Tuberosity
•Ends at medial edge of
tibia.
•Inserts over the top of
the semimembranosus,
almost a common tendon.
HAMSTRING #3
Semimembranosus
•Muscle originates on the
Ishial Tuberosity
•Ends at medial edge of
tibia.
•Inserts close to
semitendonsus, almost a
common tendon.
ARTICULAR CARTILAGE
• Articular cartilage
lines the ends of the
bones (tibia, femur) and
the undersurface of
the patella.
• Articular cartilage
protects the ends of
the bones from the
forces of running,
jumping and walking.
ARTICULAR CARTILAGE
• Articular cartilage can be
torn or crushed by a force
injury, such as a sudden
hard step or a twisting
motion where the femur
twists on top of the tibia.
• Articular cartilage can also
be worn down by use over
time, exposing the bone to
the forces of motion.
MENISCUS
• Two half-moon
shaped pieces of
cartilage that lie
between surfaces of
the femur and the
tibia.
•The meniscus (menisci)
absorb the large amount
of shock that occurs
when the bones crash
together while walking,
running and jumping.
MENISCUS
• The menisci also
provide a “cradle” for
the femur to sit atop
the tibia instead of
slipping off when
moving.
• This “cradle” helps to
keep the knee joint
stable,
MENISCUS
• The meniscus is for the most part “avascular”, meaning it
doesn't have blood vessels throughout the tissue.
• Only the outermost 20% of the meniscus has a blood supply.
As a result, a torn meniscus doesn't have the ability to
heal itself unless there is just a small tear confined to
the peripheral vascular zone.
MENISCUS
•MEDIAL MENISCUS
•LATERAL MENISCUS
•Bigger diameter
•Thinner
•Thicker
outside
edge
•More “C”
shaped