week 12 - muscles of the foot ankle and knee

Question 1

3 flexors of ankle + foot

Answer 1

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

Question 2

nerve for flexors of ankle + foot

Answer 2

tibial nerve

Question 3

tibialis posterior – origin

Answer 3

posterior shaft of tibia + fibula

Question 4

tibialis posterior – insertion

Answer 4

• all 5 tarsal bones

- bases of metatarsals 2 - 4

Question 5

tibialis posterior – action

Answer 5

• invert foot

- plantar flex ankle

Question 6

flexor digitorum longus – origin

Answer 6

posterior surface of tibia

Question 7

flexor digitorum longus – insertion

Answer 7

distal phalanges 2 - 5

Question 8

flexor digitorum longus – action

Answer 8

• flex toes 2 - 5

- invert foot

Question 9

flexor hallucis longus – origin

Answer 9

posterior fibula

Question 10

flexor hallucis longus – insertion

Answer 10

distal phalanx of big toe

Question 11

flexor hallucis longus – action

Answer 11

• flex big toe

- invert foot

Question 12

3 arches in foot

Answer 12

1. medial longitudinal (calcaneus to hallucis)
2. lateral longitudinal (calcaneous to 5th metatarsal)
3. transverse (base of the 1st and 5th metatarsals)

Question 13

4 muscles of foot

Answer 13

1. extensor digitorum brevis
2. flexor digitorum brevis
3. abductor hallucis
4. abductor digiti minimi

Question 14

general location of muscles of foot

Answer 14

• dorsal surface: extensor digitorum brevis (deep to extensor digitorum longus)
• plantar surface myo lie side-by-side:
  > flexor digitorum brevis exends down center of foot from calcaneus to phalanges
  > abductor hallucis is on big toe side of plantar surface
  > abductor digiti minimi s on little toe side of plantar surface

Question 15

nerves of muscles of foot

Answer 15

• tibial nerve (for myo on plantar surface)

- deep peroneal (for extensor digitorum brevis only)

Question 16

extensor digitorum longus – origin

Answer 16

calcaneus (dorsal surface of)

Question 17

extensor digitorum longus – insertion

Answer 17

toes 2 - 4 via extensor digitorum longus tendons

Question 18

extensor digitorum longus – action

Answer 18

extend phalanges 2 - 4

Question 19

extensor digitorum longus – nerve

Answer 19

deep peroneal nerve

Question 20

flexor digitorum brevis – origin

Answer 20

calcaneus

Question 21

flexor digitorum brevis – insertion

Answer 21

middle phalanges of toes 2 - 5

Question 22

flexor digitorum brevis – action

Answer 22

flex middle phalanges of toes 2 - 5

Question 23

flexor digitorum brevis – nerve

Answer 23

tibial nerve (burning sensation on bottom of foot –> plantar fasciitis)

Question 24

plantar fasciitis + flexor digitorum brevis

Answer 24

• inflammation of the plantar fascia, the connective tissue on the sole of the foot
• often caused by overuse of the plantar fascia or arch tendon of the foot
• aka “policeman’s heel”

Question 25

abductor hallucis -- origin

Answer 25

calcaneus

Question 26

abductor hallucis -- insertion

Answer 26

proximal phalanx of big toe

Question 27

abductor hallucis -- action

Answer 27

abduct big toe

Question 28

abductor hallucis -- nerve

Answer 28

tibial nerve

Question 29

abductor digiti minimi -- origin

Answer 29

calcaneus

Question 30

abductor digiti minimi -- insertion

Answer 30

proximal phalanx of little toe

Question 31

abductor digiti minimi -- action

Answer 31

flex little toe (should be called the flexor digiti minimi)

Question 32

abductor digiti minimi -- nerve

Answer 32

tibial nerve

Question 33

sesamoid bone of 1st metatarsal -- location

Answer 33

- located along plantar surface of foot - 1 to 2 sesamoid bones articulate w the metatarsal of big toe - sesamoids are embedded within tendon of flexor hallucis brevis

Question 34

sesamoid bone of 1st metatarsal -- function

Answer 34

- helps big toe have more flexion, for stability + strength - in general, sesamoids are found in locations where a tendon passes over a joint, such as the hand, knee, and foot; functionally, they act to protect the tendon and to increase its mechanical effect (patella is also a sesamoid bone)

Question 35

extensor hallucis brevis -- origin

Answer 35

calcaneus

Question 36

extensor hallucis brevis -- insertion

Answer 36

proximal phalanx of big toe

Question 37

extensor hallucis brevis -- action

Answer 37

extend big toe

Question 38

extensor hallucis brevis -- nerve

Answer 38

deep peroneal nerve

Question 39

flexor hallucis brevis -- location

Answer 39

plantar surface of foot

Question 40

flexor hallucis brevis -- origin

Answer 40

- cuboid | - lateral cuneiform

Question 41

flexor hallucis brevis -- insertion

Answer 41

proximal phalanx of big toe

Question 42

flexor hallucis brevis -- action

Answer 42

flex big toe

Question 43

flexor hallucis brevis -- nerve

Answer 43

tibial nerve

Question 44

quadratus plantae -- location

Answer 44

plantar surface of foot

Question 45

quadratus plantae -- origin

Answer 45

plantar surface of calcaneus

Question 46

quadratus plantae -- insertion

Answer 46

flexor digitorum longus tendon

Question 47

quadratus plantae -- action

Answer 47

flex toes 2 - 5

Question 48

quadratus plantae -- nerve

Answer 48

tibial nerve

Question 49

lateral collateral ligament (LCL) -- AKA

Answer 49

fibular collateral ligament

Question 50

lateral collateral ligament (LCL) -- location

Answer 50

- strong, thin strap that crosses knee joint | - runs from lateral epicondyle of femur to head of fibula

Question 51

lateral collateral ligament (LCL) -- function

Answer 51

- resists medial rotation of knee | - also stabilizes knee against genu varum stresses (often seen in bowlegged cowboys)

Question 52

medial collateral ligament (MCL) -- AKA

Answer 52

tibial collateral ligament

Question 53

medial collateral ligament (MCL) -- location

Answer 53

- broad ligament lies superficial to joint capsule of knee | - deep to pes anserinus tendon

Question 54

medial collateral ligament (MCL) -- function

Answer 54

- resists medial rotation of knee | - also protects against genu valgum (knock-knee) stresses

Question 55

anterior cruciate ligament (ACL) -- location

Answer 55

deep in the middle of the knee

Question 56

anterior cruciate ligament (ACL) -- function

Answer 56

- prevents tibia from moving anteriorly to femur - also prevents medial rotation of the tibia, in relation to the femur - athletes tear this when they hyperextend knee

Question 57

posterior cruciate ligament (PCL) -- location

Answer 57

deep in the middle of the knee (and works with ACL)

Question 58

posterior cruciate ligament (PCL) -- function

Answer 58

- prevents tibia from moving posteriorly under femur - hyperflexion injuries tear PCL - skiers tear these easily since they prevent rotary movement of knee

Question 59

medial + lateral menisci of knee -- location

Answer 59

- fibrocartilagnous discs attached to tibial condyles | - helps round femoral condyles sit comfortably on flat tibial plateaus

Question 60

medial + lateral menisci of knee -- function

Answer 60

- responsible for shock absorption - increases surface area, distributes weight, and reduces friction - moves sinovial fluid around in knee

Question 61

deltoid ligament of ankle -- location

Answer 61

- medial side of ankle - made up of 4 ligaments forming a triangle (seriously strong ligament!) - connects talus, calcaneus + medial malleolus

Question 62

deltoid ligament of ankle -- function

Answer 62

- allows 5 degrees of eversion | - sprains here are often in conjunction with avulson fracture

Question 63

4 deltoid ligaments of ankle (names)

Answer 63

1. posterior tibiotalar 2. tibiocalcaneal 3. anterior tibiotalar 4. tibionavicular

Question 64

lateral collateral ligaments of ankle -- location

Answer 64

- lateral side of ankle

Question 65

lateral collateral ligaments of ankle -- function

Answer 65

- stabilize distal end of fibula to calcaneus + talus - 3 ligaments that are most often torn during ankle sprains (bc nowhere near as strong as deltoid ligament on ankle's medial side + most vulnerable when foot is inverted and plantar flexed)

Question 66

3 lateral collateral ligaments of ankle (names)

Answer 66

1. anterior talofibular ligament (ATFL) (most commonly torn) 2. posterior talofibular ligament (PTFL) 3. calcaneofibular ligament

Question 67

extensor retinacula of ankle -- location

Answer 67

crosses front of ankle

Question 68

extensor retinacula of ankle -- function

Answer 68

supports tendons of extensor muscles

Question 69

posterior tibial artery

Answer 69

- pulse can be felt inferior + posterior to medial malleolus

Question 70

dorsalis pedis artery

Answer 70

- pulse can be felt bw 1st + 2nd metatarsal bones along dorsal side of foot - where the extensor hallucis endon is on dorsal foot