Posterior Thigh

Question 1

Semitendinosus

O, I, I, F

Answer 1

Origin: ischial tuberosity

Insertion: medial surface of tibia

Innervation: tibial n. (L4-S3)

Function: extend thigh, flex knee

Question 2

Semimembranosus

O, I, I, F

Answer 2

Origin: ischial tuberosity

Insertion: medial condyle of tibia

Innervation: tibial n. (L4-S3)

Function: extend thigh and flex knee

Question 3

Biceps femoris (2 heads)
O, I, I, F

Answer 3

Origin: long head-ischial tuberosity
short head-lateral lip of linea aspera

Insertion: lateral tibial condyle , head of fibula

Innervation: long-tibial n. (L4-S3)
short-peroneal n. (L4-S3)

Function: extend thigh/flex knee

Question 4

What artery supplies the posterior thigh?

Answer 4

perforating branches of profunda femoris a.

Question 5

What issues can arise from paralyzed or weakened hamstrings? Why does this occur

Answer 5

forward falls, because they aren’t long enough to allow hip flexion and knee extension at the same time

Question 6

What structures superficially bind the popliteal fossa?

Answer 6

superolaterally-bicep femoris

superomedially-semimembranosus

inferolaterally and inferomedially-lateral/medial heads of gastrocnemius

posteriorly-skin/popliteal fascia

Question 7

What makes up the floor of the popliteal fossa?

Answer 7

superior-medial and lateral supracondylar lines of femur

inferior-soleal line of tibia

Question 8

What is contained in the popliteal fossa

Answer 8

end of great saphenous vein
popliteal artery and vein
tibial and common perineal nerves
posterior cutaneous n. 
popliteal lymph stuff

Question 9

What is the relationship with the popliteal fascia to other fascia in the leg?

Answer 9

continuation of fascia lata and continues as deep fascia inferiorly

Question 10

What is the relationship of the structures in the popliteal fossa?`

Answer 10

arteries are deepest

sciatic nerve ends at superior angle and becomes tibial and common peroneal n.
tibial goes medial, peroneal goes laterally
posterior cutaneous n. supplies skin of popliteal fossa

Question 11

What is the popliteal artery a continuation of? When does it occur?

Answer 11

femoral artery, occurs when it passes through adductor hiatus.

Question 12

What branches off of the popliteal a.?

Answer 12

anterior/posterior tibial a.

Question 13

What forms an anastomotic network in the popliteal fossa?

Answer 13

genicular branch of popliteal a.
superior lateral, medial, and middle genicular a.
inferior medial and lateral genicular a.
maintains blood flow during knee flexion

Question 14

posterior tibial vein –> ? –> ?

What other vein tributes to this

Answer 14

posterior tibial vein –> popliteal vein –> femoral vein

small saphenous to popliteal

Question 15

What are the lymph nodes of the popliteal fossa? what do they drain?

Answer 15

superficial-no idea
deep-joint capsule of knee, and vessels that accompany deep vein of leg
this all eventually goes to deep inguinal lymph nodes

Question 16

What are consequences of sciatic nerve injury?

What can cause this?

Answer 16

• caused by piriformis compressing sciatic nerve
• complete section-impaired hip extension, knee flexion
• incomplete section-from stab wounds. can involve inferior gluteal n. and posterior femoral cutaneous n.

Question 17

What are the degrees of hamstring injury?

Answer 17

strain-accompanied with hematoma usually
tearing-muscle fibers tear, more painful
avulsion-tears off tibial tuberosity