M: Posterior thigh and popliteal fossa

Question 1

What does the femur articulate with?

Answer 1

Proximally with the acetabulum

Distally with the tibia

Question 2

What is the linea aspera?

Answer 2

A pair of ridges that run longitudinally along the dorsal surface and form an attachment site for several muscles of the thigh

Question 3

What is the fascia lata?

Answer 3

Deep fascia which surround the muscles of the thigh, the fascia lata also forms 3 intermuscular septa that attach to the linea aspera and divide the muscles of the thigh into 3 compartments

Question 4

What are the 3 muscle compartments of the thigh?

Answer 4

1) Anterior extensor
2) Posterior flexor
3) Medial adductor

Question 5

The posterior compartment contains the 3 hamstring muscles, what are they?

Answer 5

1) Semimembranous
2) Semitendinous
3) Biceps femoris (long head)

Question 6

What is the common proximal attachment and nerve supply of the hamstrings?

Answer 6

Common proximal attachment: ischial tuberosity

Innervation: tibial division of sciatic nerve (L5, S1, S2)

Question 7

What is the distal insertion of the biceps femoris?

Answer 7

Head of fibula

Question 8

What is the distal insertion of the semitendinous muscle?

Answer 8

Medial surface of the proximal tibia

Question 9

What is the distal insertion of the semimembranous muscle?

Answer 9

Medial and posterior surface of medial tibial condyle

Question 10

Is the short head of biceps femoris considered part of the hamstring muscles, why?

Answer 10

Not considered part of the hamstrings, does not share the common proximal attachment and innervation of the hamstring muscles

Question 11

What are the attachments and innervation of biceps femoris?

Answer 11

Origin = lateral line of linea aspera
Insertion = head of fibula 
Innervation = common fibular division of the sciatic nerve

Question 12

What are the functions of the hamstrings at the hip?

Answer 12

1) Extend the thigh at the hip joint

2) Rotate the hip joint medially and laterally

Question 13

What are the functions of the hamstrings at the knee?

Answer 13

1) Flex the leg at the knee joint

2) Rotate the leg at the knee joint - both medially and laterally

Question 14

Part of the adductor magus muscle is also considered as part of the hamstrings, why is this different?

Answer 14

Part of the medial compartment and not part of the posterior compartment of the thigh

Question 15

What 2 parts is adductor magnus composed of?

Answer 15

1) Adductor part

2) Hamstring part

Question 16

Adductor magnus has a dual nerve supply, what is it?

Answer 16

1) Adductor part - Obturator nerve (L2, L3, L4)

2) Hamstring part - Tibial division of the sciatic nerve (L2,L3,L4)

Question 17

What are the proximal attachments of the 2 parts of adductor magnus muscle?

Answer 17

1) Adductor part - Ischiopubic ramus

2) Hamstring part - Ischial tuberosity

Question 18

Why is the hamstring part of adductor magnus considered as part of the hamstrings?

Answer 18

Shares the common proximal attachment and nerve supply

Question 19

What 2 nerves does the sciatic nerve split into at the back of the thigh and what is their course?

Answer 19

At a variable point at the back of the thigh the sciatic nerve divides into the common fibular (peroneal) and tibial nerves. The common fibular nerve deviates laterally and the tibial nerve continues in the midline, both entering the popliteal fossa

Question 20

What is the popliteal fossa?

Answer 20

Diamond-shaped depression located on the posterior aspect of the knee

Question 21

Which muscles form the borders of the popliteal fossa?

Answer 21

Superior laterally - biceps femoris
Superior medially - semimembranous and semitendinous
Inferior - medial and lateral head of gastrocnemius muscle

Question 22

What structure forms the roof of the popliteal fossa?

Answer 22

Deep fascia which is continuous above with the fascia lata of the thigh and below with the deep fascia of the left

Question 23

What structures form the floor of the popliteal fossa?

Answer 23

Capsule of knee joint and adjacent surfaces of the femur and tibia and more inferiorly the popliteus muscle

Question 24

What sub-compartments is the posterior compartment of the leg divided into and how?

Answer 24

Divided into superficial and deep sub compartments by the transverse intermuscular septum

Question 25

What 3 muscles are found within the superficial posterior compartment of the leg?

Answer 25

1) Gastrocnemius
2) Soleus
3) Plantaris

Question 26

Which of the 3 muscles in the superficial posterior compartment of the leg function as a flexor of the knee aswell as a plantar flexor of the ankle joint?

Answer 26

Gastrocnemius and plantaris

Question 27

What is meant by plantarflexion?

Answer 27

Flexion of the foot downwards towards the sole

Question 28

What is meant by dorsiflexion?

Answer 28

Bending in the direction of the dorsum of the hand or foot