Muscle Chart: Posterior Thigh

Question 1

Semitendinosus

Origin, Insertion, Innervation, Blood Supply

Answer 1

Origin: Ischial tuberosity

Insertion: Proximal, medial shaft of the tibia at pes anserinus

Innervation: Tibial nerve (L4, L5, S1, S2)

Blood Supply: Deep artery of the thigh

Question 2

Semitendinosus Movements

Answer 2

Knee flexion and internal rotation

Assist with hip extension and internal rotation

Reverse action tilts the innominate bones posteriorly

Question 3

Semimembranosus

Origin, Insertion, Innervation, Blood Supply

Answer 3

Origin: Ischial tuberosity

Insertion: Posterior aspect of the medial condyle of the tibia

Innervation: Tibial nerve (L4, L5, S1, S2)

Blood Supply: Deep artery of the thigh

Question 4

Semimembranosus Movements

Answer 4

Knee flexion and internal rotation

Assist with hip extension and internal rotation

Reverse action tilts the innominate bones posteriorly

same as semitendinosus

Question 5

Biceps Femoris

Origin, Insertion, Innervation, Blood Supply

Answer 5

Origin: Ischial tuberosity (long head); lateral lip of linea aspera (short head)

Insertion: Lateral surface of the head of the fibula (tendon is split by fibular collateral ligament)

Innervation: Tibial nerve (L5, S1, S2, S3) and common peroneal/fibular nerve (L5, S1, S2)

Blood Supply: Deep artery of the thigh

Question 6

Biceps Femoris Movements

Answer 6

Knee flexion

Knee external rotation

Assist hip extension and lateral rotation

Reverse action tilts innominate bones posteriorly

Question 7

Popliteus

Origin, Insertion, Innervation, Blood Supply

Answer 7

Origin: Lateral condyle of femur

Insertion: Proximal, posterior aspect of tibia

Innervation: Tibial nerve (L4, L5, S1)

Blood Supply: Popliteal artery

Question 8

Popliteus Movements

Answer 8

Assist with knee flexion

Internal rotation of tibia relative to femur (tibiofemoral internal rotation)