Knee Extensors

Question 1

Rectus Femoris

Answer 1

O- straight head: anterior inferior iliac spine
Reflected head: rough area of ilium superior to acetabulum
I: 2 heads join quadriceps femoris tendon which inserts into base of patella
A: knee extension
I: femoral nerve L2,3,4

Question 2

Vatus Intermedius

Answer 2

O-femur, upper 2/3s of anterior and lateral surfaces
I- quadriceps femoris tendon and lateral margin of the patella and lateral condylar of tibia
A- extend the knee joint
I- femoral nerve L2,3,4

Question 3

Vatus medialis

Answer 3

O- femur: medial part of intertrochanteric line, medial lip of Linea aspera, medial supracondylar line
I- quadriceps tendon and medial border of patella
A- extension of knee
I- femoral nerve L2,3,4

Question 4

Vatus lateralis

Answer 4

Needs to be strong for extension
O- lateral part of intertrochanteric line, lateral margin of greater trochanter, lateral margin of gluteal tuberosity, lateral lip of linea aspera
I- quadriceps tendon and lateral border of patella
A- extends the knee
I- femoral nerve, L2,3,4