Unit 5 - Lower Limb: Knee Joint (Ex. IV)

Question 1

What are its articulations?

Answer 1

M and L articulations between condyles of femur and tibia

articulation between femur and patella

Question 2

What are its primary movements?

Answer 2

flexion and extension

some rotation and sliding can occur

Question 3

What are the articulations of the patella?

Answer 3

patellar surface of femur between M and L condyles –> protects joint A

Question 4

Where is the patella located?

Answer 4

embedded in tendon of quadriceps femoris –> holding tendon away from joint increases leverage of the muscle

Question 5

What does stability between the articular surface of the femur and tibia depend on?

Answer 5

ligaments connecting tibia and femur

muscles surrounding the joint ==> quadriceps femoris

Question 6

From what does the fibrous capsule of the knee joint receive additional support?

Answer 6

patellar retinacula
–> capsular ligaments that attach A to quadriceps tendon
patella
extracapsular ligaments

Question 7

extracapsular ligaments

Answer 7

support the fibrous capsule
patellar ligament
  - distal part of quadriceps tendon 
  - supports knee joint A
  - patella --> tibial tuberosity
collateral ligaments
  - limit rotation
  - prevent M and L dislocation
  - taught in extension; on slack during flexion
  - L (fibular) collateral ligament (LCL)
    - cordlike
    - unattached to joint capsule
    - L epicondyle of femur --> head of fibula
  - M (tibial) collateral ligament (MCL)
    - flat and ribbonlike 
    - attached to joint capsule and M meniscus
    - M epicondyle of femur --> M condyle and A-M aspect of tibia
oblique popliteal ligament
  - expansion of semimembranosus 
  - supports joint capsule P and L
arcuate popliteal ligament
  - fibular head --> P knee joint
  - reinforces joint capsule P and L

Question 8

intra-articular ligaments

Answer 8

provide stability during movements of the joint
cruciate ligaments
- w/ in joint capsule
- lie external to synovial layer
- stability in all positions and limit rotation and prevent A and P dislocation
- A cruciate ligament (ACL)
- arises from A intercondylar part of tibia –> P-L to M aspect of L femoral condyle
- P cruciate ligament (PCL)
- arises from P intercondylar part of tibia –> A-M to L aspect of M femoral condyle
transverse ligament ==> connects menisci to e/o along A edges
P meniscofemoral ligament ==> joins L meniscus to PCL and M femoral condyle

Question 9

menisci

Answer 9

fibrocartilaginous pads that deepen articular surfaces of tibial plateau
tallest @ outer rim –> attached to joint capsule and intercondylar ridge
M meniscus
- C-shaped
- immobile ==> attachment to tibial collateral ligament
L meniscus
- circular
- mobile during flexion and extension

Question 10

What is the path of the synovial layer of the knee joint?

Answer 10

lines internal surface of joint capsule –> (P aspect extends into) intercondylar space of joint cavity –> reflects around intracapsular ligaments –> divides joint space into M and L parts

Question 11

bursae

Answer 11

at least 12 associated w/ the knee:
suprapatellar bursa
  - deep to quadriceps femoris tendon
  - communicates w/ cavity of knee joint
prepatellar bursa
  - subcutaneous over patella
superficial infrapatellar bursa
  - subcutaneous over patellar ligament
deep infrapatellar bursa
  - deep to patellar ligament
anserine bursa
  - between pes anserinus and tibial collateral ligaments

Question 12

What type of joint is it?

Answer 12

modified synovial hinge joint

Question 13

What runs in between the LCL and L meniscus preventing them from attaching to one another?

Answer 13

tendon of popliteus