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Flashcards in Ankle/Foot Deck (58)
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1
Q

What does the ankle primarily refer to?

A

talocrural joint: articulation among tibia, fibula, and talus

2
Q

What does foot refer to?

A

all tarsal bones and joints distal to ankle

3
Q

What is the rearfoot?

A

hindfoot) consists of talus, calcaneus, and subtalar joint

4
Q

What is the midfoot?

A

consists of remaining tarsal bones, including transverse tarsal joint and distal intertarsal joints

5
Q

What is the forefoot?

A

consists of metatarsals and phalanges, including tarsometatarsal joints

6
Q

What transfers 10% of body weight?

A

shaft of fibula

7
Q

Distal end of tibia twisted externally around its long axis approximately______relative to its proximal end

A

20-30 degrees

8
Q

What is the wrist referred to as?

A

lateral tibial torsion, based on orientation of bone’s distal end relative to its proximal end

9
Q

What are the major joints of the ankle?

A

talocrural, subtalar, and transverse tarsal joints

10
Q

70% of the talus surface is covered with what?

A

articular cartilage

11
Q

Plane and AOR of dorsiflexion and plantar flexion

A

parallel to sagittal plane

ML AOR

12
Q

Plane and AOR of eversion and inversion?

A

parallel to frontal plane

AP AOR

13
Q

Plane and AOR of abduction and adduction?

A

parallel to horizontal plane and vertical AOR

14
Q

Pronation defined as motion that has elements of:

A

Eversion, abduction, and dorsiflexion

15
Q

Supination defined as motion that has elements of:

A

Inversion, adduction, and plantar flexion

16
Q

What provides major source of natural stability to ankle?

A

confining shapr of talocrural joint

17
Q

What percentage of compressive forces pass through the talus and tibia?

A

90-95%

18
Q

What percentage of compressive forces pass through lateral region of talus and fibula?

A

5-10%

19
Q

Arthrokinematics of dorsiflexion at talocrural joint:

A

talus rolls forward relative to leg and slides posteriorly

20
Q

Arthrokinematics of plantar flexion at talocrural joint:

A

talus rolls posteriorly as bone slide anteriorly

21
Q

What can extreme and violent dorsiflexion of ankle (leg over foot) do:

A
  • can injure collateral ligaments

- injure ligaments that support distal tibiofibular joint and interosseous membrane (high ankle sprain)

22
Q

What is the loose packed position of the talocrural joint:

A

full plantar flexion (slackens most collateral ligaments of the ankle)

23
Q

Pronation and supination during non weight-bearing activities:

A

calcaneus moves relative to fixed talus

24
Q

In weight bearing (stance phase of walking) pronation and supination occur:

A

as calcaneus remains relative stationary

25
Q

What are the three articulations of the subtalar joint?

A

the posterior, middle, and anterior facets of calcaneus and talus

26
Q

Prominent posterior articulation of subtalar joint occupies about what?

A

70% of total articular surface area

27
Q

AOR of the subtalar joint:

A

pierces lateral-posterior heel and courses through subtalar joint in anterior, medial, and superior directions

28
Q

Where is the AOR of the subtalar joint positioned?

A

42° from horizontal plane and 16° from sagittal plane

29
Q

Pronation and supination of subtalar joint occurs:

A

as calcaneus moves relative to talus (or vice versa when foot planted) in arc perpendicular to AoR

30
Q

What two of the three main components of pronation and supination are strongly evident:

A

inversion/eversion

abduction/adduction

31
Q

Pronation has main components of:

A

eversion and abduction

32
Q

Supination has main components of

A

inversion and adduction

33
Q

Inversion exceeds eversion by:

A

nearly double
inversion=22.6 degrees
eversion=12.5 degrees

34
Q

What composes the mid-tarsal joint:

A

Talonavicular joint

Calcaneocuboid joint

35
Q

The mid tarsal joint connects:

A

rearfoot and midfoot

36
Q

The tarsal joint moves through what kind of path?

A

more oblique, equally through all three planes

37
Q

What joints function cooperatively to control most of pronation and supination posturing of entire foot?

A

transverse tarsal and subtalar joints

38
Q

Transverse tarsal joints allow for what of midfoot while standing on uneven surfaces?

A

pronation/supination

39
Q

What does the talonavicular joint resemble?

A

ball and socket

40
Q

What does the talonavicular joint provide?

A

substantial mobility to medial (longitudinal) column of foot

41
Q

What is mobility of talnavicular joint expressed as?

A

twisting (inverting and everting) of midfoot relative to rearfoot

42
Q

What does the talonavicular joint consist of?

A

talus, navicular and spring ligament

43
Q

What forms the lateral component of transverse tarsal joint?

A

junction of anterior (distal) surface of calcaneus with proximal surface of cuboid

44
Q

What does the Relative inflexibility of calcaneocuboid joint provide?

A

stability to lateral (longitudinal) column of foot

45
Q

What muscle is the prime supinator of the foot?

A

tibialis posterior

46
Q

What rarely moves without the subtalar joint?

A

transverse tarsal joint

47
Q

What accounts for most of pronation and supination throughout foot?

A

Combining motions across subtalar and transverse tarsal joints

48
Q

What are the two AOR for movement at transverse tarsal joint?

A

Longitudinal axis: eversion and inversion

Oblique axis: abduction/dorsiflexion and adduction/plantar flexion

49
Q

What is the amount of pure inversoin/eversion of midfoot?

A

20-25° of inversion and 10-15° of eversion

50
Q

What is the primary load-bearing and shock-absorbing structure of foot?

A

medial longitudinal arch

51
Q

What are the bones of the medial arch?

A

calcaneus, talus, navicular, cuneiforms, and associated three medial metatarsals

52
Q

What nonmuscular structures maintain height and general shape of arch?

A

plantar fascia, spring ligament (plantar calcaneonavicular), and first tarsometatarsal joint

53
Q

During standing, what structure maintains height of medial longitudinal arch?

A

deep plantar fascia

54
Q

What is pes planus?

A

flattening or arch

55
Q

What is pes cavus?

A

abnormally raised medial longitudinal arch

56
Q

What motions of the hip are associated with exaggerates pronation of subtalar joint during weight bearing?

A

Internal rotation, flexion, and adduction

57
Q

What motions of the knee are associated with exaggerates pronation of subtalar joint during weight bearing?

A

Increased valgus stress

58
Q

What motions of the rearfoot are associated with exaggerates pronation of subtalar joint during weight bearing?

A

Pronation (eversion) with a lowering of medial longitudinal arch