Posterior Thigh

Question 1

Biceps Femoris

Answer 1

Origin:

• long head: ischial tuberosity
• short head: linea aspera and lateral supracondylar line of femur

Insertion: lateral side of head of fibula

Innervation:

• long head: tibial part of sciatic nerve
• short head: common fibular part of sciatic nerve

Blood Supply: perforating branches of profunda femoris, inferior gluteal, and medial circumflex femoral arteries

Action: flexes and laterally rotates leg, extends thigh at hip

Question 2

Semimembranosus

Answer 2

Origin: ischial tuberosity

Insertion: posterior part of medial condyle of tibia

Innervation: tibial part of sciatic nerve

Blood Supply: perforating branches of profunda femoris and medial circumflex femoral arteries

Action: flexes leg and extends thigh

Question 3

Semitendinosus

Answer 3

Origin: ischial tuberosity

Insertion: superior part of medial surface of tibia

Innervation: tibial part of sciatic nerve

Blood Supply: perforating branches of profunda femoris and medial circumflex femoral arteries

Action: flexes leg and extends thigh