Posterior Thigh Muscles

Question 1

Sartorius

Answer 1

Origin: Anterior superior iliac spine and superior part of the notch inferior to it

Insertion: Superior part of the medial surface of tibia

Action: Flexes, abducts, and laterally rotates the thigh at the hip joint; flexes the knee joint

Question 2

Semitendinosus

Answer 2

Origin: Ischial tuberosity

Insertion: Medial surface of the superior part of tibia

Actions: Extends at the hip to move the thigh; flexes the leg at the knee and rotates it medially; with flexed hip and knee, it extends the trunk

Question 3

Semimembranosus

Answer 3

Origin: Ischial tuberosity

Insertion: Posterial part of the medial condyle of tibia

Actions: Extends the thigh at the hip; flexes the leg at the knee and rotates it medially; with flexed hip and knee it also flexes the trunk

Question 4

Biceps Femoris

Answer 4

Origin: Long head - Ischial tuberosity
Short head - Linea aspera and lateral supracondylar line of femur

Insertion: Lateral side of the head of fibula; tendon at this site split by fibula collateral ligaments of the knee

Action: Flexes leg at the knee and rotates it laterally; Extends thigh at the hip (long head only)