Knee Muscles

Question 1

Rectus Femoris

Answer 1

O: AIIS
I: tibial tuberosity via patellar tendon
A: hip flexion and knee extension
N: femoral nerve L2, L3, L4

Question 2

Vastus Lateralis

Answer 2

O: linea aspera
I: tibial tuberosity via patellar tendon
A: knee extension
N: femoral nerve L2, L3, L4

Question 3

Vastus Medialis

Answer 3

O: linea aspera
I: tibial tuberosity via patellar tendon
A: knee extension
N: femoral nerve L2, L3, L4

Question 4

Vastus intermedialis

Answer 4

O: anterior femur
I: tibial tuberosity via patellar tendon
A: knee extension
N: femoral nerve L2, L3, L4

Question 5

Semimembranosus

Answer 5

O: ischial tuberosity
I: posterior surface of medial condyle of tibia
A: hip extension and knee flexion
N: sciatic nerve L5, S1, S2

Question 6

Semitendinosus

Answer 6

O: ischial tuberosity
I: anteromedial surface of proximal tibia
A: hip extension and knee flexion
N: Sciatic nerve L5, S1, S2

Question 7

Biceps Femoris

Answer 7

O: long head: ischial tuberosity
Short head: lateral lip of linea aspera
I: fibular head
A: long head: hip extension and knee flexion
Short head: knee flexion
N: long head: sciatic nerve tibial division L5, S1, S2
Short head: common fibular nerve L5, S1, S2

Question 8

Popliteus

Answer 8

O: lateral condyle of femur
I: Posterior medial condyle of tibia
A: initiates knee flexion
N: tibial nerve L4, L5, S1

Question 9

Gastrocnemius

Answer 9

O: medial and lateral condyles of femur
I: posterior calcaneus
A: knee flexion , ankle plantarflexion
N: tibial nerve S1, S2