Exam 4A

Question 1

muscles of posterior compartment of thigh

Answer 1

biceps femoris
semitendinosus
semimembranosus

innervation: sciatic excepts SH biceps femoris (common fibular)

Question 2

biceps femoris origin

Answer 2

LH: ischial tuberosity
SH: linea aspera and lateral supracondylar line of femur

Question 3

biceps femoris insertion

Answer 3

head of fibula

Question 4

biceps femoris innervation

Answer 4

LH: tibial of sciatic
SH: common fibular of sciatic

Question 5

biceps femoris action

Answer 5

flexion/lateral rotation of leg at knee

extension of thigh at hip (LH only)

Question 6

semitendinosus origin

Answer 6

ischial tuberosity

Question 7

semitendinosus insertion

Answer 7

medial shaft of tibia

pes anserinus

Question 8

semitendinosus innervation

Answer 8

tibial of sciatic

Question 9

semitendinosus action

Answer 9

flexion/medial rotation of leg at knee

extension of thigh at hip

Question 10

semimembranosus origin

Answer 10

ischial tuberosity

Question 11

semimembranosus insertion

Answer 11

posterior aspect of medial condyle of tibia

Question 12

oblique popliteal ligament

Answer 12

tendon gives rise to fibers that pass superior and laterally to reinforce posterior aspect of capsule of knee joint (from semimembranosus)

Question 13

posterior compartment of thigh blood supply

Answer 13

no major artery

perforating branches of profunda femoris artery

Question 14

perforating arteries anastomose with each other

Answer 14

1st perforating artery takes part in cruciate anastomosis (with inferior gluteal and medial and lateral circumflex femoral arteries)

4th perforating artery anastomoses with branches of popliteal artery that supply distal parts of hamstring muscles

in this way, a line of anastomoses is established from gluteal region to popliteal fossa

Question 15

sciatic nerve

Answer 15

leaves gluteal region, passes deep to LH of biceps femoris

depends along midline of posterior thigh, overlapped posteriorly by adjacent margins of biceps femoris and semimembranosus

anterior to adductor magnus

Question 16

sciatic nerve divisions

Answer 16

tibial
common fibular
muscular

Question 17

muscular divisions of sciatic nerve

Answer 17

long head of biceps femoris
semitendinosus
semimembranosus
hamstring part of adductor magnus (from tibial division)
short head of biceps femoris (from common fibular division)

Question 18

popliteal fossa

Answer 18

diamond shaped space posterior to knee joint

Question 19

popliteal fossa boundaries

Answer 19

superolateral: biceps femoris
superomedial: semitendinosus, semimembranosus
inferolateral: lateral head of gastrocnemius, planters
inferomedial: medial head of gastrocnemius

Question 20

popliteal fossa anterior (floor)

Answer 20

popliteal surface of femur, articular capsule of posterior aspect of knee joint, popliteus muscle

Question 21

popliteal fossa posterior (roof)

Answer 21

deep fascia over popliteal fossa, continuous superiorly with fascia late and inferiorly with crural fascia

Question 22

contents of popliteal fossa

Answer 22

popliteal artery and vein
terminal part of small saphenous vein
tibial and common fibular (peroneal) nerves and their branches
terminal part of posterior cutaneous nerve of thigh
genicular branch of obturator nerve (terminal part of its posterior branch)
popliteal lymph nodes
adipose tissue

Question 23

popliteal artery

Answer 23

begins at adductor hiatus as a continuation of femoral artery; terminates at inferior border of popliteus muscle by dividing into anterior and posterior tibial arteries

most deeply located structure in popliteal fossa, lies in contact with fossa’s floor (vulnerable to supracondylar fractures of femur)

in midline of popliteal fossa, popliteal vein lies posterior to popliteal artery and tibial nerve lies posterior to popliteal vein

Question 24

popliteal artery muscular branches

Answer 24

gastrocnemius
soleus
plantaris
distal parts of hamstring muscles

Question 25

popliteal artery genicular branches

Answer 25

supply knee joint and participate in arterial anastomosis around it: 2 superior (medial and lateral), 2 inferior (medial and lateral) and 1 middle

Question 26

superior medial and lateral genicular arteries

Answer 26

curve around distal femur, superior to femoral condyles, to reach anterior aspect of knee joint

Question 27

inferior medial and lateral genicular arteries

Answer 27

curve around proximal tibia to reach anterior aspect of knee joint

Question 28

middle genicular artery

Answer 28

unpaired branch; arises from anterior aspect of popliteal artier opposite back of knee joint pierces oblique popliteal ligament and supplies cruciate ligaments and synovial membrane inside joint

Question 29

popliteal vein

Answer 29

formed by union of anterior and posterior tibial veins at inferior border of popliteus muscle terminates at adductor hiatus, becomes femoral vein ascends through popliteal fossa posterior to popliteal artery and anterior to tibial nerve

Question 30

popliteal vein tributaries

Answer 30

correspond to branches of popliteal artery | small saphenous vein

Question 31

popliteal lymph nodes

Answer 31

embedded in connective tissue and fat of popliteal fossa receive superficial lymph vessels from lateral part of foot and leg (accompany small saphenous vein) receive deep lymph vessels accompanying anterior and posterior tibial vessels (drain all deep structures of foot and leg) efferent vessels from popliteal lymph nodes accompany popliteal and femoral vessels and terminate in deep inguinal lymph nodes

Question 32

tibial nerve

Answer 32

originates in lower ⅓ of thigh from sciatic nerve, descends almost vertically through popliteal fossa, posterior to popliteal artery and vein leaves popliteal fossa and enters posterior compartment of leg by passing deep (anterior) to tendinous arch of soleus muscle

Question 33

tibial nerve branches

Answer 33

muscular articular sural

Question 34

tibial nerve muscular branches

Answer 34

gastrocnemius soleus plantaris popliteus

Question 35

sural nerve

Answer 35

descends between 2 heads of gastrocnemius and pierces crural fascia (deep fascia of leg) in upper to mid-parts of posterior leg, joined by sural communicating branch (from lateral sural cutaneous nerve) at a variable level (some authors call the nerve “medial sural cutaneous” as it originates from tibial nerve and “sural” after it joins communicating branch) sural nerve accompanies small saphenous vein, passes posterior and then inferior to lateral malleolus, continues along lateral border of foot and little toe as lateral dorsal cutaneous nerve sural nerve supplies skin over inferolateral part of posterior aspect of leg and along lateral borders of foot and little toe

Question 36

common fibular nerve

Answer 36

originates in lower ⅓ of thigh from sciatic nerve runs inferiorly and laterally in popliteal fossa, following medial border of biceps femoris leaves popliteal fossa by passing superficial to plantaris and lateral head of gastrocnemius passes posterior to head of fibula and then lateral to neck of fibula, deep to uppermost fibers of fibularis longus muscle (common injury site), where it divides into 2 terminal branches: superficial and deep fibular (peroneal) nerves

Question 37

lateral rural cutaneous nerve | common fibular branch

Answer 37

gives off rural communicating branch that joins sural nerve

Question 38

recurrent articular branch | common fibular branch

Answer 38

supplies proximal tibiofibular joint and knee joint