Posterior Thigh Muscles

Question 1

Origin: Semitendinosus

Answer 1

Ischial Tuberosity

Question 2

Origin: Semimembranosus

Answer 2

Ischial Tuberosity

Question 3

Origin: Biceps Femoris

Answer 3

Long Head: Ischial Tuberosity

Short Head: linea aspera and lateral supracondylar line of femur

Question 4

Insertion: Semitendinosus

Answer 4

Medial surface of superior part of tibia

Question 5

Insertion: Semimembranosus

Answer 5

Posterior part of medial condyle of tibia

Question 6

Insertion: Biceps Femoris

Answer 6

Lateral side of head of fibula; tendon at this site split by fibular collateral ligament of knee

Question 7

Innervation: Semitendonosus

Answer 7

Tibial division of sciatic nerve (L2-S2)

Question 8

Innervation: Semimembranosus

Answer 8

Tibial division of sciatic nerve (L5-S2)

Question 9

Innervation: Biceps Femoris

Answer 9

Long head: tibial division of sciatic nerve (L5-S2)

Short head: common fibular (peroneal) division of sciatic nerve (L5-S2)

Question 10

Main Actions: Semitendinosus

Answer 10

Extends thigh at hip; flexes leg at knee and rotates it medially; with flexed hip and knee, extends trunk

Question 11

Main Actions: Semimembranosus

Answer 11

Extends at thigh at hip; flexes leg at knee and rotates it medially; with flexed hip and knee, extends trunk

Question 12

Main Actions: Biceps Femoris

Answer 12

Flexes leg at knee and rotates it laterally; extends thigh at hip e.g. when starting to walk (long head only)