Posterior Thigh

Question 1

thigh boundaries

Answer 1

proximal: inguinal lig (ant) + ischiopubic ramus (med) + gluteal fold (post)

distal: knee joint

Question 2

tibia

Answer 2

-weight bearing
-medial
-big guy
-vertical in leg an tibial plateau is horizontal

Question 3

fibula

Answer 3

non weight bearing bc does not directly contact femur

lateral

Question 4

thigh osteology

Answer 4

fall on ‘hip’ usually iliac crest OR greater trochanter

hip fractures usually proximal femoral fractures (neck or interchrochanteric line)
-neck of femur more likely than femoral shaft

Question 5

superficial fascia

Answer 5

aka subcutaneous tissue or hypodermis

continuous w/ superfical fascia of abdomen/buttocks/rest of free lower limb

Question 6

superficial fascia

contents

Answer 6

-fat (thins as distal bc greater energy demand in thigh than leg)
-superficial veins
-cutaneous nerves
-lymph vessels and nodes

females more buttocks, hips, thigh fat

Question 7

fascia lata

definition

Answer 7

aka deep fascia of thigh
continous w/ TL fasica and deep fascia of popliteal and leg (crural)

Question 8

fascia lata

structure

Answer 8

thick and strong w/ 3 layers of dense coll CT
-extra thick laterally w/i IT band (iliotibila tract)

limits outward muscle expansion, resists stretch and distortion

Question 9

IT band

definition

Answer 9

aponeurosis w/i fascia lata

og @ iliac tubercule > gerdy tubercle of tibia

Question 10

3 compartments

fascia lata

Answer 10

1. posterior- knee flexors, tibial sciatic N
2. anterior- knee extensors, hip flexors, femoral N
3. medial- hip adductors, obturator N

separated by intermuscular septa

Question 11

posterior compartment

Answer 11

main knee flexors w/ hamstrings (can also hip extend weakly except short head)

tibial divison of sciatic goes to everything except short head
-short head is common fib of sciatic

Question 12

hamstring muscles

Answer 12

lateral:
1. short head biceps femoris (linea aspera > head of fibula)
2. long head biceps femoris (IT > head of fibula)

medial:
3. semimembranosous (IT>medial side proximal tibia)
4. semitendonosous (IT > medial side proximal tibia)

Question 13

pes anserinus

Answer 13

muscles that insert:
1. sartorius (ant thigh)
2. gracilis (medial thigh)
3. semitendinosus (post thigh)

medial side proximal tibia

Question 14

hamstring strain

Answer 14

overstretched/torn from:
-inadequate warmup
-strength imbalances
-lack of flexibility

other symps: bruising, weakness, loss of motion

graded: I (overstretch) II (partial tear) III (complete rupture tendon)

more likely tear long head than short

Question 15

sciatic N split

Answer 15

supply posterior compartment

do not become tibial N and common fibular N until sciative splits distally @ apex of popliteal fossa

tibial N is most superficial struture in popliteal fossa

Question 16

cutaneous innervation

posterior thigh

Answer 16

MAIN = posterior femoral cutaneous N from both divs of S1-3 + some of lateral femoral cutaneous branches

runs deep to fascia lata, parallel with sciatic

Question 17

cutaneous innervation

Werning Rule

Answer 17

for given nerve, area where motor axons supply muscles is proximal to the skin that cutaneous axons supply

since developmentally motor axons enter first, then sensory

cutaneous branches of tibial and common fib distal

Question 18

vascular supply

posterior

Answer 18

nothing is exclusive to posterior

hamstrings = 4 perforating A
proximal ends of semis = inferior gluteal
distal end of all hamis = small branches of popliteal and genicular A

Question 19

perforating arteries

Answer 19

branches of deep femoral

start in anterior thigh compartment > travel posterior > pierce adductor magnus muscle and intercompartment septae

Question 20

popliteal fossa

boundaries

Answer 20

hamstrings (thigh) and gastrocnemius (leg)

floor = popliteal surface of posterior femur and knee capsule

roof = popliteal fascia/deep fascia and skin

Question 21

popliteal fossa

content

Answer 21

mostly fat
tibial N and common fib N
popliteal V and A (deepest)
popliteal lymph nodes and lymphatic vessels

tibial N > popliteal V > popliteal A

Question 22

popliteal A

Answer 22

aka femoral after reaches fossa thru adductor magnus > split into anterior and posterior tibial A (in post leg compartment)

5 genicular artery branches supply knee joint, genicular anastomosis

Question 23

popliteal pulse

Answer 23

difficult since A so deep, easier @inferior part closer to tibia

pt prone and knee semi-flexed to relax fascia and hamstrings

if weak or absent = femoral A obstruction

Question 24

collateral circulation

Answer 24

chain of anastomoses b/t gluteal region to popliteal fosssa

1. cruciate anastomosis- most important to post thigh
2. genicular anastomosis- most important to popliteal fossa esp during full knee flexion

Question 25

veins

Answer 25

1. anterior + posterior tibial V > popliteal@below fossa > femoral @ant thigh
2. smaller/lesser saphenous enter popliteal V in fossa, superficial vein in superficial fascia so drains superficial veins of post leg and lat foot
3. perforating V travel with A
4. popliteal V travel with A

Question 26

lymphatics

Answer 26

all vessels drain into superficial inguinal lymph nodes

superficial and deep popliteal lymph nodes drain posterior and lateral leg
-send lymph to deep inguinal lymph nodes

Question 27

IT band

function

Answer 27

1. assist in maintaining typical standing posture
2. reduce bending stress on femur during locomotion
   -tightens when weight shifts to one side

Question 28

lateral collateral ligament

Answer 28

distal end runs in the middle of biceps femoris (both) insertion when split into Y shape

inserts on fibular head

Question 29

motor innervation

posterior compartment

Answer 29

MAIN = tibial division of sciatic N

common fibular div of sciatic for short head of biceps femoris