2. The knee is the largest joint
in the human body and is
considered the most
complicated one.
The knee consists of the
lateral and medial
compartments of the
tibiofemoral joint and the
patellofemoral joint.
3. The stability of knee is based primarily on its soft
tissue constraints rather than on its bony
configuration.
The knee condyler synovial joint. It has two condylar
jt. b/w the condyles of the femur and tibia, one
saddle jt. b/w the femur and the patella.
The knee is also a complex jt. as the cavity is divided
by the menisci.
5. THE ARTICULAR SURFACES OF KNEE JOINTARE
AS FOLLOWING:
•THE CONDYLES OF FEMUR.
•THE PATELLA.
•THE CONDYLES OFTIBIA.
6.
7. – A – Lateral Condyle
• Smaller radius of curvature
• Smaller in all dimensions
• Extends more anteriorly
– B – Medial Condyle
• Larger radius of curvature
• Extends more distally
– C – Intercondylar notch
8. •Anteriorly, the condyles are seperated by
Patello femoral Groove.
• Posteriorly, the condyles are separated by the
intercondylar notch.
11. Double condyloid knee joint is also referred
to as Medial & Lateral Compartments of
the knee.
Double condyloid joint with 30freedom of
Angular (Rotatory) motion.
Flexion/Extension
Medial/lateral (int/ext) rotation
Abduction/Adduction
12.
13. Interface between articular
side of the patella and the
intercondylar(trochlear
groove) of the femur.
Main function of this joint is
transmission of forces.
14. Base- for quad tendon attachment
Apex - for patellar tendon attachment
Anterior surface
Posterior articular surface-convex in all direction
4-5 mm
Thick articular
cartilage
Odd facet
Vertical ridge
Large lateral
&small med facet
15. • As many as 13 Bursae have been
described around Knee Joint.
•The Four are Anterior
• Four are Lateral
• Four are Medial.
16.
17. These are Four in Numbers.
• Subcutaneous Prepatellar Bursa.
• Subcutaneous Infrapatellar Bursa.
• Deep Infra Patellar Bursa.
• Suprapatellar Bursa.
18. There are Four Lateral Bursae.
• A Bursa deep to Lateral Head of
Gastrocnemius.
• A Bursa b/w Fibular Collateral
Ligament and the Biceps Femoris.
• A Bursa b/w Fibular Collateral
Ligament andTendon of Popliteus.
• A Bursa b/wTendon of Popliteus and
Lateral Condyle of theTibia.
19. The Four Medial Bursae are as follows.
• A Bursa deep to the Medial head of
Gastrocnemius.
•TheAnserine Bursa.(Complicated)
• A Bursa deep to theTibialCollateral
Ligament.
• A Bursa deep to Semimembranosus
23. Fibrous capsule is very thin and is deficient anteriorly
where it is replaced by quadriceps femoris, patella and
ligamentum patellae.
Femoral attachment- Attached about one and half cm
beyond the articular margins.
-Anteriorly - deficient
-Posteriorly- Intercondylar line
-Laterally- Encloses capsule of poplitius
Tibial attachment- Attached about half to one cm
beyond the articular margins.
-Anteriorly- Margin of condyles of tibial tuberosity
-Posteriorly- Intercondylar ridge
24. Common tendon of insertion of the quadriceps
femoris.
7.5 cm long and 2.5 cm broad
Attached above the apex of the patella and below
to the upper part of tibial tuberosity.
Related to the superficial and deep infrapatellar
bursae and to the infrapatellar pad of fat.
25.
26. Medial ligament-
Attached superiorly to the medial epicondyle of
femur.
Inserts into proximal tibia.
Lateral ligament-
Approx 5 cm long.
Attached superiorly to the lateral epicondyle of
femur.
Inserts posteriorly to the head of fibula.
27. STRUCTURE FUNCTION MECHANISMOF INJURY
MCL
LCL
Resists
-valgus
-knee xtension
-extremes of axial
rotation(external
rotation)
Resists
-varus
-knee extension
-extremes of axial
rotations
1.Valgus producing force
with foot planted
2.Severe hyperextension of
the knee
1.Varus producing force
with foot planted
2.Severe hyperextension of
the knee
28.
29. Oblique popliteal ligament-
Expansion from the tendon of semimembranous
Attached to the indercondylar line and lateral
condyle of the femur.
Arcuate popliteal ligament-
Expansion from short lateral ligament
Extends backwards from the head of fibula, arches
over the tendon of popliteus and attached to the
post. Intercondylar area of the tibia.
30. Provide multiple plane stability to the knee
most notably in the sagittal plane
Guide the natural arthrokinematics,especially
those related to the restraint of sliding
motions between the tibia and the femur
Contribute to proprioception of the knee
31.
32. Two bands-
AMB(anteromedial band),
PLB (posterolateral band)
Attached below to the
anterior intercondylar area
of the tibia
Courses superiorly,
posteriorly & laterally;
attaches to the lateral
femoral condyle
33. STRUCTURE FUNCTION MECHANISMOF INJURY
ACL 1.Most fibers resist
extension
2.Resits extremes of
varus valgus and axial
rotation
1.Large valgus producing
force with foot planted
2.Large axial rotation
torque with the foot
firmly planted
3.Any combination of
above involving strong
quadriceps contraction
with the knee in full or
near full extension
4.Severe hyperextension
of the knee
34. control the normal
rolling and gliding
movement of the knee
posterior rolling of
femur tightens up ACL
which leads to anteror
translation
35. Anteromedial
bundle is taut in
both flexion &
extension, while the
posterolateral
bundle is taut on
extension only
36.
37. Two bands- ALB and PMB
Attached below to the
posterior intercondylar area
of the tibia
Courses superiorly,
anteriorly and medially;
attaches to the medial
femoral condyle
38. STRUCTURE FUNCTION MECHANISMOF INJURY
PCL 1.Most fibers resist knee
flexion
2.Resist extremes of varus
valgus and axial rotation
1.Falling on a fully flexed knee with
ankle fully plantarflexed
2. forceful posterior translation of
tibia(dashboard injury)or anterior
translation of femur,especially
while the knee is flexed
3.Large axial rotation or valgus
varus applied torque to the knee
with the foot firmly
planted,especially when the knee is
flexed
4.Severe hyperextension of the knee
causing a large gapping of the
posterior side of the joint
39. Check femur from being
displaced anteriorly on the
tibia
Tibia from being displaced
posteriorly on femlur.
It tightens during flexion & is
injured much less frequently
than ACL.
Near full extension the ALB are
lax and PMB are taut whereas
in 90-100 degrees of flexion
PMB are lax and ALB are taut.
40. Sheets of fibrocartilage with a
thick peripheral convex border
and a thin inner concave
border which is attached to the
capsule
Lateral meniscus is “O” shaped
Medial meniscus is “C” shaped
and is thicker posteriorly than
anteriorly
Ant. and post. Ends of menisci
are attached to tibia and are
referred to as Ant. and Post.
Horns.
41. • Peripheral thick part is vascular.
• Inner part is avascular and is nourished by synovial
fluid.
• Reduce the compressive stress across the
tibiofemoral joint & serve as shock absorber.
• Stabilising the joint during motion
• Lubricating the articular cartilage
• Providing proprioception
• Helping to guide knee arthrokinematics
42. Extension
Meniscal migrate Anteriorly :
• Because of menisco-patellar ligament
Flexion
Menisci migrate posteriorly because of
• Semimembranosus attachment to medial
meniscus
• Popliteus attachment to lateral meniscus
43. It connects the anterior ends of the medial
and lateral meniscus.
44.
45. • FIVE GENICULAR BRANCHES OF POPLITEAL
ARTERY.
• DESCENDING GENICULAR BRANCH OF FEMORAL
ARTERY.
• DESCENDING BRANCH OF LATERAL
CIRCUMFLEX FEMORAL ARTERY.
•TWO BRANCHES OF ANTERIORTIBIAL ARTERY.
• CIRCUMFLEX FIBULAR BRANCH OFTIBIAL ARTEY.
46. FOLLOWING NERVES SUPPLY
THE KNEE JOINT:
• FEMORAL NERVE
THROUGH ITS BRANCHES
TOVASTI(ESPVASTUS
MEDIALIS)
• SCIATIC NERVETHROUGH
GENICULAR BRANCHES OF
TIBIAL AND COMMON
PERONEAL N.
• OBTURATOR NERVE
THROUGH ITS POSTERIOR
DIVISION.
• INFRAPATELLAR BRANCH
50. Vasti Muscles
• O:
VL – Greater trochanter,upper ½
of linea
aspera;
VI – Anterolateral upper 2/3 of
femur,
lower ½ of linea aspera
VM –Distal intertrochanteric line,
medial
linea aspera
• I:Tibial tuberosity via
infrapatellar
tendon
• N: Femoral
• A: Knee extension
55. HAMSTRINGS
Weakness of hamstring may result in significant loss of knee flexion strength
difficulty bending and lifting.
Tightness of hamstring may result in limitation in knee extension ROM when the
hip is flexed.
POPLITEUS
Origin- Lateral femoral condyle
Insertion- Posteriomedial tibia
Nerve-Tibial
An important rotator and flexor of knee joint.
It is a key to the knee.(it provide internal rotation torque that help
mechanically to unlock the knee).
Dynamically stabilises both lateral and medial sides of the
knee(the strong intracapsular tendon of the popliteus provide
significant resistance to a varus load applied to the knee, stabilise
medially by limiting excessive external rotation.
56. MEDIAL ROTATORS OF THE KNEE
Pes Anserine Muscles
• Sartorius (most anterior)
• Gracilis (middle)
• Semitendinosus (most
posterior)
1)Sartorius
• O: ASIS
• I: Anteromedial tibial
flare (pes anserine)
• N: Femoral
• A: Hip flexion,
Hip abduction,
Hip external rotation
57. Gracilis
• O: Symphysis pubis,
inferior
ramus of pubic bone
• I: Anteromedial tibial
flare (pes anserine)
• N: Obturator
• A: Hip adduction,
Hip flexion,
Knee flexion
58. Iliotibial Band/TFL
• O: Anterior superior iliac
crest
• I: Anterolateral tibia at
Gerdy’s tubercle
• N: Superior gluteal
• A: Hip flexion,
Hip abduction,
Hip internal rotation
59. STABLIZERS OF KNEE
Classification of supporting structure of knee
Functional
Static stabilizer
Dynamic stabilizer
Location
Medial joint compartment
Lateral joint compartment
64. LATERAL JOINT STABILIZERS
The structure included in static & dynamic
stabilization of knee :
IT band
Biceps femoris
Popliteus
LCL
Meniscofemoral arcuate
ACL
Lateral patellar retinaculum
65. ROLE OF VMO AS A KNEE STABILIZER
The pull of the rectus femoris
and vastus intermedius is parallel
to the shaft of femur. The pull of
vastus lateralis is lateral is lateral
to the femur. The patellar tendon
pulls the patella distally. The sum
of these forces is a proximal and
lateral pull on the patella.
Fiber arrangement of VMO
makes it ideally suited to
provide stability
68. It estimates the lateral pull of the
quadriceps muscle.
Q angle is a function of location
of tibial tuberosity rather than
the shaft of tibia.
Therefore, torsional deformities
of the tibia and femur and rotary
malalighnments of foot can alter
the Q angle without changing the
valgus alighnment of knee
An increased Q angle indicates an
increase lateral pull on the patella
and appears to increase the risk
of anterior knee pain.
69. Q Angle increases due
to:
a) Femoral anteversion
b) External tibial torsion
c) Laterally displaced tibial
tubercle
d) Genu valgum
70.
71. SCREW-HOME MECHANISM
Screw home rotation has been described as an
conjunct rotation, it is mechanically linked(or
coupled) to the flexion and extension
kinematics and cannot be performed
independently.
Locking of the knee in full extension requires
about 10 degrees of external rotation during
last 30 degrees or more of extension.
72. During last 30 degrees of extension
Automatic rotation(tibial external rotation in
open chain) and (femoral internal rotation in
closed chain motion)
Locking of the knee joint(which is a stable and
closed packed position of knee joint)
73.
74. POPLITEUS MUSCLE:THE “KEY TO THE
KNEE”
• As the extended and locked
knee prepares to flex, the
popliteus provides an
important internal rotation
torque that helps to
mechanically unlock the
knee.
• Because of the muscle’s
enhanced leverage to
initiate internal rotation of
th the knee, it has been
referred to as “key to the
knee”.
75. References
• Joint Structure and Function: A
Comprehensive Analysis, Fourth Edition,
Cynthia C. Norkin, 2005
• Joint Structure and Function: A
Comprehensive Analysis, Third Edition, Cynthia
C. Norkin
• Clinical Kinesiology and Anatomy, Fourth
Edition, Lynn S. Lippert, 2006
