Knee joint

Question 1

what is the function of the patella?

Answer 1

• mechanical advantage to quadricep tendon.

Question 2

the knee joint is a mismatch of various shapes, affecting stability. what structures provide a solution to this?

Answer 2

• menisci.
• capsule.
• ligaments.
• muscles.

Question 3

what is the function of menisci?

Answer 3

menisci are concentric plates of wedge shaped fibrocartilage that deepened the articulation surfaces.
- act as shock absorbers.

Question 4

which of the two menisci are more prone to damage? and why?

Answer 4

• the medial meniscus is attached to the medial collateral ligament which limits its movement making it more prone to damage.
• whereas lateral meniscus moves more and is less prone to damage.

Question 5

what ligaments are involved in strengthening the knee joint?

Answer 5

• intra-capsular : cruciate.
• capsule : oblique popliteal.
• extra-capsular : collateral.

Question 6

the cruciate ligaments contain 2 separate ligaments. compare and contrast.

Answer 6

• Anterior cruciate ligament is weaker than posterior cruciate as it has relatively poor blood supply. PCL main stabiliser in weight bearing flexed knee.
• ACL limits anterior movement of tibia on femur.
• PCL limits posterior movement of tibia on femur.

Question 7

differentiate between medial and lateral collateral ligament.

Answer 7

• mediaL resists Lateral vaLgus forces on tibia whereas lateRal resist varRus medial forces on tibia.

Question 8

Bursae are fluid filled sacs of synovial fluid. there are 6 found around the knee joint. can you name them?

Answer 8

• supra-patellar.
• pre-patellar.
• superficial infra-patellar.
• deep infra-patellar.
• semimembranous.
• subartorial.

Question 9

what muscles are involved in knee flexion?

Answer 9

• hamstrings
  ( bicep femoris, semitendenosus, semimembranosus)
• assisted by gracillus, sartorius, popliteus, gastrocnemius.

Question 10

what muscles are involved in knee extension?

Answer 10

• quariceps

vastus lateralis, vastus medialis, vastus intermedius, rectus femoris

Question 11

what muscles are involved in medial rotation of knee at flexion?

Answer 11

• semitendinosus, semimembranosus, gracilis, sartorius, popliteus.

Question 12

what muscles are involved in lateral rotation of knee at flexion?

Answer 12

• biceps femoris!!