Posterior Thigh & Popliteal Fossa

Question 1

What muscles form the 4 borders of the popliteal fossa?

Answer 1

Superomedial: semimembranosus, semitendinosus
Inferomedial: medial head of gastrocnemius
Superolateral: biceps femoris
Inferolateral: lateral head of gastrocnemius

Question 2

What nerve innervates the skin of the middle posterior thigh?

Answer 2

Posterior femoral cutaneous (S1-S3)

Question 3

Name the 3 muscles in the posterior thigh

Answer 3

Semimembranosus
Semitendinosus
Biceps femoris

Question 4

All posterior thigh muscles originate on the _____ (except short head biceps femoris)

Answer 4

Ischial tuberosity

Question 5

Origin of Short head of biceps femoris

Answer 5

Linea aspera & lateral supracondylar ridge of femur

Question 6

All posterior thigh muscles are innervated by the… (except short head biceps femoris)

Answer 6

Tibial division of sciatic nerve

Question 7

Innervation of short head of biceps femoris

Answer 7

Common fibular (peroneal) branch of sciatic nerve

Question 8

Branches of sciatic nerve

Answer 8

At popliteal fossa:
Tibial division
Common fibular (peroneal) division

Question 9

Branches of tibial nerve

Answer 9

Sural n
Lateral plantar n
Medial plantar n

Question 10

Branches of common fibular nerve

Answer 10

Sural n
Deep fibular n
Superficial fibular n
Lateral Sural cutaneous n

Question 11

The tibial nerve supplies the ____

Answer 11

Posterior leg

Question 12

The lateral and medial plantar nerves supply the ____

Answer 12

Foot

Question 13

The deep fibular nerve supplies the ____

Answer 13

Anterior leg

Question 14

The superficial fibular nerve supplies the ____

Answer 14

Lateral leg

Question 15

Origin of biceps femoris

Answer 15

• Long: ischial tuberosity
• Short: lateral lip of linea aspera & lateral supracondylar ridge of femur

Question 16

Insertion of biceps femoris

Answer 16

Head of fibula & lateral condyle of tibia

Question 17

Innervation of biceps femoris

Answer 17

Long: tibial division of sciatic n
Short: common fibular division of sciatic n

Question 18

Action of biceps femoris

Answer 18

• flex & laterally rotate leg at the knee
• long head extends the thigh at the hip

Question 19

Origin & insertion of semitendinosus

Answer 19

O: ischial tuberosity
I: medial surface of proximal tibia

Question 20

Innervation of semitendinosus

Answer 20

Tibial division of sciatic n

Question 21

Action of semitendinosus

Answer 21

• flex leg & medially rotate tibia at the knee
• extend thigh at the hip

Question 22

What structures form the pes anserinus?

Answer 22

Tendons of semitendinosus, sartorius, and gracilis

Question 23

Origin & insertion of semimembranosus

Answer 23

O: ischial tuberosity
I: posterior aspect of medial condyle of tibia

Question 24

Innervation of semimembranosus

Answer 24

Tibial division of sciatic n

Question 25

Action of semimembranosus

Answer 25

- flex leg & medially rotate tibia at the knee - extend thigh at the hip

Question 26

Part of the semimembranosus tendon forms the ____

Answer 26

Oblique popliteal ligament

Question 27

Describe the contents of the popliteal fossa

Answer 27

Popliteal a Popliteal v Common fibular n Tibial n

Question 28

Describe the Sural nerve

Answer 28

- Sural communicating n (from common fibular n) - medial Sural cutaneous n (from tibial n) Join to form Sural n

Question 29

The Sural nerve supplies…

Answer 29

- skin along distal 2/3 of posterolateral calf - lateral foot, over 5th digit

Question 30

Describe variation in the formation of the Sural nerve

Answer 30

Communicating & medial Sural nn join much lower in the leg

Question 31

Describe the branches of the popliteal artery

Answer 31

- superior lateral & superior medial genicular aa - middle genicular a - Sural aa - inferior lateral & inferior medial genicular aa

Question 32

What is the passageway for the popliteal artery?

Answer 32

Adductor hiatus (Above this = femoral a)

Question 33

The popliteal artery ends by splitting into the ____ and ____

Answer 33

Anterior & posterior tibial aa

Question 34

The main blood supply to the knee joint is the ____

Answer 34

Popliteal a

Question 35

The posterior tibial artery gives rise to the ____

Answer 35

Fibular artery