Posterior Leg

Question 1

Division Ant/Post

Answer 1

tibia (medial)
interosseous membrane
fibula
posterior intermuscular septum (lat/post)

Question 2

transverse intermuscular septum

Answer 2

divides superficial and deep compartments of posterior leg

Question 3

superficial muscles

Answer 3

1. gastrocnemius (medial + lateral heads)
2. soleus
3. plantaris

ankle plantarflexion

Question 4

deep muscles

Answer 4

1. popliteus
2. flexor digitorum longus
3. tibialis posterior
4. flexor hallucis longus

toe flexion + weak plantarflex

Question 5

motor innervation

Answer 5

all tibial baby L4-S3
-branches into medial + lateral plantar N

Question 6

superficial muscle insertion

Answer 6

all 3 insert on calcaneal tuberosity
-gastrocnemius + soleus = calcaneal/achilles tendon
-plantaris = own tendon, not blended w/achilles

Question 7

triceps surae

Answer 7

2 heads of gastrocnemius + soleus
95% of plantarflex strength

fibers twist for shock absorption + efficient propulsion

Question 8

diabetic tendinopathy

Answer 8

degenerative process from glycation end product (from high BP) acc in load bearing collagenous structures aka tendons

abnormal collagen/matrix = dec vascular integrity so poor healing

Question 9

gastrocnemius

o/i/v

Answer 9

medial head: og @ medial femoral condyle + popliteal surface
lateral head: og @ lateral femoral condyle + lateral margin

in @ calcaneal tuberosity

posterior tibial A (main) + popliteal A (proximal)

Question 10

gastrocnemius

function

Answer 10

main ankle plantarflex when knee extended + ankle dorsiflex
-assist knee flexion (since crosses joint)

if knee if flexed then not plantarflex AT ALL

sprinting/jumping since high levels fast twitch fibers

Question 11

soleus

o/i/v

Answer 11

arched og @ soleal line + medial tibia + posterior head fibula + proximal fibular shaft

in @ calcaneal tuberosity

posterior tibial A (main) + popliteal A (proximal) + fibular A (lateral)

Question 12

soleus

function

Answer 12

ankle plantarflexion

if knee flexed = SOLE/only plantarflexor

standing/walking bc high levels slow twitch fibers

stroll with soleus

Question 13

tendinous arch soleus

Answer 13

gap in proximal attachement of soleus (closer to knee/popliteal region)

tibial N + popliteal A enter the post compartment
-popliteal A splits into posterior + anterior tibial after enters arch

Question 14

plantaris

Answer 14

og @ inferior end of lateral supracondylar line + oblique popliteal ligament

in @ calcaneal tuberosity

popliteal A only since right behind knee

scrawny thing

Question 15

plantaris

function

Answer 15

proprioception bc high number of muscle spindles

Question 16

popliteus

o/i/v

Answer 16

og @ lateral femoral condyle + lateral meniscus
in @ posterior surface tibia above soleal line

genicular A

Question 17

popliteus

function

Answer 17

unlock knee when full extension/foot is planted by rotate femur laterally (full knee extension rotates femur lateral=lock)

if knee full extension/foot NOT planted then rotate tibia medially

Question 18

flexor digitorum longus

o/i/v

Answer 18

og @ medial posterior surface tibia below soleal line
in @ base of digits 2-5/distal phalanges

posterior tibial A

most medial deep muscle, starts medial ends lateral

Question 19

flexor digitorum longus

function

Answer 19

weak plantarflex
passive support of longitudinal foot arch

Question 20

tibialis posterior

o/i/v

Answer 20

og @ posterior tibia below soleal line + interosseous membrane + posterior surface fibula

in @ tuberosity of navicular (main) + all 3 cuneiforms + cuboid + base of MT 2-4

posterior tibial A

Question 21

tibialis posterior

function

Answer 21

inverts foot + weak plantarflexion

anterior also does inversion but dorsiflex instead of plantar

Question 22

flexor hallicus longus

o/i/v

Answer 22

og @ inferior 2/3 posterior fibula + inferior interosseous membrane (lateral)

in @ base of distal phalanx digit 1 (medial)

fibular A

most lateral deep muscle, starts lateral ends medial

Question 23

flexor hallicus longus

function

Answer 23

flex digit 1 at all joints
+ weak plantarflexion
+ passive support longitudinal foot arch

crosses FDL tendons at the foot

Question 24

DTH

down to hug

Answer 24

medial > lateral @ posterior leg

flexor DIGITORUM longus
TIBIALIS posterior
flexor HALLUCIS longus

Question 25

TDH

Tom, Dick, And Very Nervous Harry

Answer 25

anterior > posterior @ medial ankle

TIBIALIS posterior
flexor DIGITORUM longus
posterior tibial ARTERY + VEIN
tibial NERVE
flexor HALLUCIS longus

Question 26

branches of popliteal A

Answer 26

1. genicular A- 5 of them (popliteus)
2. anterior tibial A
3. posterior tibial A > fibular A

Question 27

branches of posterior tibial A

Answer 27

1. circumflex fibular A (but usually off of anterior)
2. fibular A
3. posterior medial malleolar A
4. posterior medial calcaneal A
5. medial + lateral plantar A (terminates, to supply sole foot)

Question 28

branches fibular A

Answer 28

1. communicating branch (anastomose fibular A + posterior tibial)
2. posterior lateral malleolar A
3. posterior lateral calcaneal A

Question 29

posterior tibial pulse

Answer 29

diminished pulse = longstanding atherosclerosis from peripheral arterial disease

stenosis of superficial femoral and popliteal A

arterial blood clots from presence of plaques rupturing

Question 30

sensory innervation

Answer 30

1. sural N = medial sural + sural communicating, does middle
2. lateral sural cutaneous (from common fib) does lateral
3. saphenous n (from femoral) does medial