Leg and Popliteal Fossa

Question 1

how many muscles are there in the anterior compartment of the leg?

Answer 1

4

Question 2

name the 4 muscles in the anterior compartment of the leg

Answer 2

tibialis anterior
extensor digitorum longus
extensor hallucis longus
peroneus tertius (fibularis tertius)

Question 3

what innervates the anterior leg?

Answer 3

deep peroneal nerve (L4-L5)

Question 4

what are the attachments of the tibialis anterior?

Answer 4

lateral tibia to base of metatarsal I

Question 5

what is the general action of the anterior compartment of the leg?

Answer 5

dorsiflexion and inversion at ankle

Question 6

what is the action of tibialis anterior?

Answer 6

dorsiflexion and inversion of foot

Question 7

the tendons of which muscle can be palpated on the dorsum of the foot?

Answer 7

extensor digitorum longus

Question 8

what are the attachments of the extensor digitorum longus?

Answer 8

lateral condyle of tibia and medial surface of fibular to each of the four lateral toes

Question 9

what is the action of extensor digitorum longus?

Answer 9

extension of lateral 4 toes

dorsiflexion of foot

Question 10

what are the attachments of extensor hallucis longus?

Answer 10

medial surface of fibular shaft - crosses anterior to ankle joint - base of distal phalanx of great toe

Question 11

what are the actions of extensor hallucis longus?

Answer 11

extension of great toe

dorsiflexion of foot

Question 12

what are the attachments of peroneus (fibularis) tertius?

Answer 12

medial surface of fibular

metatarsal V

Question 13

what is the action of peroneus (fibularis) tertius?

Answer 13

eversion and dorsiflexion of foot

Question 14

how many muscles are there in the lateral leg?

Answer 14

2

Question 15

name the 2 muscles in the lateral leg?

Answer 15

peroneal longus
peroneal brevis
(fibularis!)

Question 16

what is the action of the two lateral leg muscles?

Answer 16

eversion - realistically, prevention of excessive inversion of foot while running

Question 17

describe the path of peroneal (fibularis) longus

Answer 17

origin: superior and lateral surface of fibula + lateral tibial condyle
tendon descends, passes into foot posterior to lateral malleolus
crosses under foot (like stirrup!) and attaches to medial bones - medial cuneiform and metatarsal I

Question 18

what is the action of peroneal (fibularis) longus?

Answer 18

everision and plantar fexion

supports lateral and transverse arches of foot

Question 19

describe the path of peroneal (fibularis) brevis

Answer 19

origin: inferior and lateral surface of fibular shaft
descends into foot posterior to lateral malleolus
attaches to tubercle on metatarsal V

Question 20

what is the action of peroneal (fibularis) brevis?

Answer 20

eversion of foot

Question 21

what innervates the lateral leg?

Answer 21

superficial peroneal nerve (L4-S1)

Question 22

how many muscles are there in the posterior leg?

Answer 22

7

Question 23

how many muscles are in the superficial layer of the posterior leg?

Answer 23

3

Question 24

how many muscles are in the deep layer of the posterior leg?

Answer 24

4

Question 25

name the 3 muscles in the superficial layer of the posterior leg?

Answer 25

gastrocnemius plantaris soleus

Question 26

where do the superficial muscles of the posterior leg insert?

Answer 26

calcaneus - calcaneal tendon (Achille's heel)

Question 27

what is the action of the posterior leg muscles?

Answer 27

plantar flexion and inversion

Question 28

what innervates the posterior leg?

Answer 28

tibial nerve (terminal branch of sciatic)

Question 29

where do the two heads of gastrocnemius originate?

Answer 29

``` lateral = lateral femoral condyle medial = medial femoral condyle ```

Question 30

what is the action of gastrocnemius?

Answer 30

plantar flexion at ankle | also crosses knee, so flexes there

Question 31

name the 4 muscles innervated by the tibial nerve

Answer 31

the 3 superficial posterior leg muscles (gastrocnemius, plantaris, soleus) and the popliteus muscle

Question 32

where does the plantaris originate?

Answer 32

lateral supracondylar line of femur

Question 33

what is the action of plantaris?

Answer 33

plantar flexes at ankle, flexes at knee, although not vital for either of these movements

Question 34

where does soleus originate?

Answer 34

soleal line of tibia and proximal fibular area

Question 35

what is the action of soleus?

Answer 35

plantar flexion

Question 36

name the 4 muscles of the deep layer of the posterior leg

Answer 36

popliteus tibialis posterior flexor digitorum longus flexor hallucis longus

Question 37

what is the action of popliteus?

Answer 37

"unlocks" knee by laterally rotating femur

Question 38

what are the attachments of popliteus?

Answer 38

posterior tibia to lateral condyle of femur

Question 39

what is the action of tibialis posterior?

Answer 39

inverts and plantar flexes foot | maintains medial arch of foot

Question 40

what are the attachments of flexor digitorum longus?

Answer 40

medial surface of tibia to plantar surfaces of lateral 4 toes

Question 41

what is the action of the flexor digitorum longus?

Answer 41

flexes lateral 4 toes

Question 42

what are the attachments of flexor hallucis longus?

Answer 42

posterior surface of fibula to plantar surface of phalanx of great toe

Question 43

what is the action of flexor hallucis longus?

Answer 43

flexes great toe

Question 44

what forms the superiomedial border of the popliteal fossa?

Answer 44

semimembranous

Question 45

what forms the superiolateral border of the popliteal fossa?

Answer 45

biceps femoris

Question 46

what forms the inferomedial border of the popliteal fossa?

Answer 46

medial head of gastrocnemius

Question 47

what forms the inferolateral border of the popliteal fossa?

Answer 47

plantaris and lateral head of gastrocnemius

Question 48

what forms the floor of the popliteal fossa?

Answer 48

posterior knee joint capsule

Question 49

what forms the roof of the popliteal fossa?

Answer 49

popliteal fascia and skin

Question 50

what are the contents of the popliteal fossa?

Answer 50

``` (medial to lateral) popliteal artery popliteal vein tibial nerve common peroneal nerve ```