Knee Joint

Question 1

Bones of the Knee

Answer 1

-Femur (lateral/medial condyle)
-Tibia (transfer weight from knee to ankle)
-Fibula (helps knee alignment)
-Patella

Question 2

Functions of Patella

Answer 2

-Protects from anterior knee trauma
-Increase quads mechanical advantage
-Creates larger moment arm for quadriceps, less force needed to extend knee

Question 3

Knee Movement- Evolute

Answer 3

-Medial-lateral axis of rotation for flexion/extension not fixed
-It migrates within femoral condyles
-Curved path of axis of rotation is the “evolute”

Question 4

Knee Movement- “Screw-home”

Answer 4

-Locking knee in full extension requires 10 degrees of external rotation

Question 5

Articulations at Knee

Answer 5

-Tibiofemoral (medial/lateral condyles articulate with tibial condyles)
-Patellofemoral (anterior femur articulates with patella)

Question 6

Supporting structures of the tibial femoral joint

Answer 6

-Menisci
-Bursae
-Ligaments (collateral or cruciate)

Question 7

Components and functions of menisci

Answer 7

-Medial menisci injured 2x more than lateral
-Functions
1) reduce compressive stress
2) Stabilize joint during motion
3) Lubricate articular cartilage
4) Provides proprioception

Question 8

Ligaments at the knee

Answer 8

-2 collateral ligaments
1) Lateral collateral ligament (LCL)
2) Medial collateral ligament (MCL)
-2 cruciate ligaments
1) Anterior cruciate ligament (ACL)
2) Posterior crucaite ligament (PCL)

Question 9

Unhappy Triad

Answer 9

-Ligament will often tear here
ACL, MCL, medial mensici

Question 10

Knee Valgus vs. Varus

Answer 10

-Valgus= knees bent in
Valgus producing force adds tension to MCL

-Varus= knees bent out
Varus producing force adds tension to PCL

Question 11

Muscles at the Knee

Answer 11

• Rectus femoris: knee extensor, hip flexor
  -Semimembranous: knee flexor, hip extensor
  -Biceps femoris: knee flexor, hip extensor
  -Gastocnememius: knee flexor, ankle plantarflexor