Posterior Thigh Muscles (Hamstrings) (plus popliteus)

Question 1

Semitendinosus

Origin

Insertion

Answer 1

Origin:

• Ischial tuberosity

Insertion:

• Med. proximal tibia

Question 2

Semitendinosus

Action

Innervation

Answer 2

Action:

• Extends hip
• Flexes knee

Innervation:

• Tibial n.
• (L4-S3)

Question 3

Semimembranosus

Origin

Insertion

Answer 3

Origin:

• ​Ischial tuberosity

Insertion:

• Med. tibial condyle

Question 4

Semimembranosus

Action

Innervation

Answer 4

Action:

• Extends hip
• Flexes knee

Innervation:

• Tibial n.

Question 5

Biceps Femoris

Origin

Insertion

Answer 5

Origin:

• Long head: Ischial tuberosity
• Short head: Lat. femur

Insertion:

• Head of fibula (two bellies of muscle combine so only single tendon insertion)

Question 6

Biceps Femoris

Action

Innervation

Answer 6

Action:

• Extends hip
• Flexes knee

Innervation:

• Long Head: Tibial n.
• Short head: Common fib./peroneal (L4-S2)

Question 7

Popliteus*

Origin

Insertion

N.B: Not really a thigh muscle

Answer 7

Origin:

• Proximal to soleal line

Insertion:

• Inserts into lateral femoral epicondyle

Question 8

Popliteus*

Action

Innervation

*N.B: Not really a thigh muscle

Answer 8

Action:

• Unlocks the knee
• Can cause medial rotation to prevent excess lateral rotation

Innervation:

• Tibial nerve (L4-S3)

Question 9

Hamstrings

other action

Answer 9

Can also cause a small degree of rotation (medial or lateral).