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Flashcards in Hip Deck (102)
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1
Q

T/F: The hip joint can move in all 3 planes.

A

true: horizontal, frontal, sagittal

2
Q

What structure in the hip joint increases congruency and surface area?

A

labrum

3
Q

T/F: The shape of the hip joint is well suited for stability.

A

true

4
Q

What is the angle of inclination? What’s a normal value for this angle?

A
  • angle of inclination = how angled up the head of the femur is
  • measured via line through shaft of femur and line through neck of femur
  • normal = 125 deg
5
Q

If the angle of inclination is less than 125 degrees, what is the term for this? What can this cause at the knee?

A

coxa vara, can cause genu valgus at the knee

6
Q

What are the benefits and disadvantages from having an angle of inclination less than 125 degrees?

A

advantage -

1) increased moment arm for abductors, improving force
2) alignment may improve joint stability

disadvantage-

1) increased bending moment arm, which increases sheer force at femoral neck
2) shortens the fibers for glut med, completely negating the better moment arm

7
Q

At what age is the angle of inclination permanent?

A

5 yo

8
Q

What does the angle of inclination impact?

A

fiber arrangement/length, moment arm, joint alignment and stability

9
Q

With coxa valga, what is the angle of inclination?

A

greater than 125, more like 150

10
Q

T/F: We start out with coxa valga at birth.

A

true, start at 150 deg and then it gets to 125

11
Q

What are the negatives about having a coxa valga?

A

1) decreased moment arm for hip abductors

2) poor alignment favors dislocation

12
Q

Increased sheer force on the femur neck occurs with what angle of inclination deformity?

A

coxa vara

13
Q

Increased fiber length of abductors is a pro for what, coxa vara or coxa valga?

A

coxa valga

14
Q

Decreased moment arm is a disadvantage for coxa vara or coxa valga?

A

coxa valga

15
Q

In which deformity, coxa valga or vara, is the femur more likely to dislocate?

A

coxa valga, >125

16
Q

What are the positives and negatives for coxa valga?

A
  • positives = decreased sheer forces on neck, increased abductor fiber length
  • negatives = easy dislocation, decreased moment arm for force of abductors
17
Q

What are the positives and negatives for coxa vara?

A
  • positives = increased stability, increased moment arm for abductor force
  • negatives = shortened fiber length of abductors, more sheer force on neck
18
Q

What is femoral torsion? How do you assess this, what position must the patient be in?

A
  • how the femoral head and neck align with the condyles below
  • patient must be prone
19
Q

How is torsion measured? What’s a normal torsion angle?

A
  • Line through condyles and line through neck of femur

- normal torsion angle = 15 degrees anteversion (head twisted forward)

20
Q

What is the normal angle of torsion for a baby? When does it resume the normal angle value?

A

~35 degrees, weight bearing decreases this angle till it’s normal around 17/18 yo

21
Q

What classifies a femur as retroverted?

A
22
Q

What can excessive anteversion do to the adult? (3)

A

1) decrease abductor moment arm
2) destabilize joint
3) articular incongruence

23
Q

How do we compensate for coxa vara/valga?

A

by going into genu valgus/varus at the knee, respectively

24
Q

How do we compensate for retroversion? Anteversion?

A
retroversion = toe out to compensate
anteversion = toe in to compensate
25
Q

What can accompany coxa vara?

A

coxa vara = genu valgus = anteversion = toeing in

26
Q

Why is toeing in and out a bad compensation?

A

it may lead to more joint stability, but toeing out shortens the external rotators
- pt may complain of butt pain and present with limited internal rotation ROM

27
Q

T/F: Excessive torsion can cause femoral anteversion.

A

true

28
Q

What does the acetabular anteversion angle tell you? What’s normal?

A

tells you how well the anterior acetabulum covers the anterior head of the femur; normal is 20 degrees

29
Q

In what plane do you assess the acetabular anteversion angle?

A

in the horizontal plane

30
Q

T/F: The closed pack position for the hip is the same as the most congruent position for the hip.

A

false!! this is the only joint where it’s not like that

31
Q

What are open and closed pack positions for the hip?

A
  • open = 30 degrees flexion, 30 deg abduction, slight ER

- closed = full extension with slight IR and abduction

32
Q

What is the position of maximal congruency for the hip?

A

90 deg flexion, moderate ER and abduction

- capsule and ligaments on slack here tho, not much passive tension on joint here

33
Q

T/F: Too little of an acetabular anteversion angle can cause osteoarthritis.

A

true, as well as dislocation

34
Q

What ligament is most important in preventing hip extension?

A

iliofemoral (y-ligament)

35
Q

What hip ligament is the only ligament resisting IR?

A

ischiofemoral ligament

36
Q

What is the position of comfort for the hip?

A

30 deg flexion
30 deg abduction
slight ER

37
Q

When is the iliofemoral ligament taut?

A

in extension and ER

38
Q

The superior fibers of what ligament become taut in full adduction?

A

ischiofemoral

39
Q

What ligament is taut in abduction, extension, and ER?

A

pubofemoral

40
Q

What ligament assists in walking with forward hand-held crutches? How does it do this?

A

y-ligament
- the line of gravity (and body weight) is now way posterior to the hip, and the y-ligament becomes especially taut to resist that extension moment

41
Q

What limits hip flexion when the knee is bent?

A

gluteus maximus and posterior capsule

42
Q

What limits hip flexion when the knee is straight?

A

hamstrings and posterior capsule

43
Q

What’s the difference in PROM for hip flexion when knee is flexed and knee is straight?

A

knee flexed = 120 deg

knee straight = 70-80 deg

44
Q

Can you get more hip extension when the knee is flexed or when the knee is straight?

A

more with knee extended = 0-20 deg (hip ligaments and iliopsoas resist)
- only like 5 deg with knee bent due to stretching of rectus femoris

45
Q

How much abduction ROM do we get, and what limits it?

A
  • abduction = 40 deg

- limited by pubofemoral

46
Q

How much adduction ROM do we get, and what limits it?

A
  • adduction = 25 deg

- limited by ischiofemoral superior fibers, contralateral limb, and tight abductors

47
Q

Do we get more internal or external rotation?

A

more external (45) vs internal (35)

48
Q

What limits internal rotation?

A

ischiofemoral superficial fibers and external rotators

49
Q

What limits external rotation?

A

iliofemoral, pubofemoral, internal rotators

50
Q

What is the lumbopelvic rhythm? When is it ipsidirectional and when is it contradirectional?

A

lumbopelvic rhythm = when pelvis and lumbar spine rotate together

1) ipsidirectional = during far reach we want both lumbar spine and pelvis to rotate forward
2) contradirectional = during gait, pelvis rotates forward and L-spine rotates back to keep eye gaze up

51
Q

What offsets the tenency of supralumbar trunk to follow anterior pelvic rotation?

A

lumbar lordosis limits anterior pelvic tilt

52
Q

Do we get more anterior tilt when sitting or standing? Why?

A

more in sitting (30 deg) than standing (20 deg) because the tissues are relaxed in sitting

53
Q

When weight-bearing limb goes into IR, what happens at the contralateral pelvis?

A
IR = contralateral pelvis moves forward
(ER = pelvis moves backward
54
Q

When a weight-bearing limb adducts, what happens at the contralateral pelvis?

A

hip lowers on contralateral side (vs hip hike when opposite limb abducts)

55
Q

T/F: Full potential of pelvis-on-femur rotation requires lumbar spine and trunk to follow pelvis.

A

true

56
Q

T/F: Spine side-bends toward abducted limb during pelvis-on-femur abduction.

A

false, side bends away from abducted limb, side bends toward adducted limb

57
Q

Is the spine convex or concave on the abducted limb side?

A

convex on abducted limb

concave on adducted limb

58
Q

When NWB limb swings forward during gait, what does the opposite stance limb do?

A

internally rotate

59
Q

What arthrokinematics occur at the hip for femur-on-pelvis IR?

A

IR = anteriomedial roll, posteriolateral slide of femur head on acetabulum

60
Q

What arthrokinematics occur during hip abduction?

A

ab = rolls superiolaterally, slides inferiomedially

61
Q

What arthrokinematics occur during hip extension?

A

ext = roll posterior and inferior, slide anterior and superior

62
Q

How much ROM for hip flexion do we get?

A

knee bent = 120

knee straight = 70-80

63
Q

How much ROM for hip extension do we get?

A

knee bent = 5

knee straight = 20

64
Q

How much ROM for hip IR/ER do we get?

A
IR = 35 deg
ER = 45 deg
65
Q

Besides hip flexion, can iliopsoas do any other movements?

A
  • some adduction when leg is abducted

- some ER when limb is abducted

66
Q

What does sartorius do?

A

hip flexion, abduction, external rotation

67
Q

What does TFL do?

A

abduction, hip flexion, IR, stabilizes knee

68
Q

What muscle is both a hip flexor and knee extender?

A

rectus femoris

69
Q

Why is a lumbar lordosis sometimes painful?

A

There’s a lot of sheer forces at L5-S1 with excessive lordosis, as well as facet compression

70
Q

What helps offset the anterior tilt of the pelvis during swing phase of gait? (when femur flexes)

A

abdominals

71
Q

Which hip adductor is a powerful hip extensor?

A

adductor magnus

72
Q

In what position do the adductors generate flexion torque?

A

when hip is at 0-40 degrees flexion

73
Q

When can the adductor magnus kick in for hip extension?

A

when hip is at 40-70 degrees of hip flexion

74
Q

When can the other adductors take over some hip extension?

A

greater than 100 degrees of hip flexion

75
Q

What’s a better hip flexor, adductor magnus or longus?

A

longus is a better hip flexor, magnus is a great extensor

76
Q

Are the adductors internal or external rotators also?

A

INTERNAL

- they insert on the back of the femur, but the bowing causes the line of pull to be in line with IR

77
Q

There are no muscles that do solely, purely this motion.

A

IR, since no muscle’s line of force lies purely in horizontal plane

78
Q

When do the ERs (like piriformis, superior glut max, and posterior glut min) become IRs?

A

at 90 degrees of hip flexion

79
Q

What muscles are secondary IRs?

A

pectineus
adductor longus/brevis
TFL
glut med and min, anterior fibers

80
Q

What does a scissoring gait look like?

A

both femurs internally rotated, flexed, and adducted

81
Q

Why do people with a scissoring gait have increased IR potential?

A

due to the poor activation of hip extensors, and the likely flexion contracture, this causes the ERs to be put in a better position to do IR, so more IR torque will be produced :(

82
Q

How do we decrease a scissoring gait with therapy?

A

focus on activation of the gluteus max

83
Q

What ERs are responsible for more IR when hip is flexed?

A

gluteus max, superior fibers
piriformis
gluteus min, posterior fibers

84
Q

Which fibers of gluteus maximus are` external rotators?

A

superior fibers

85
Q

What are your primary hip extensors?

A

gluteus max, all fibers
hamstrings (biceps femoris LH, ST, SM)
adductor magnus, posterior head

86
Q

What are your secondary hip extensors?

A

glut med, posterior fibers
adductor magnus, anterior fibers
rest of adductors @ >70 degrees flexion

87
Q

In a slight forward lean, what muscle is activating the most to keep us from bending too forward?

A

glut max

- in a more forward lean, the hamstrings really increase activity

88
Q

What does glut min do?

A
  • considered a primary abductor, but really more of a stabilizer
  • posterior fibers of glut min do ER
89
Q

T/F: All abductors are capable of producing a IR or ER torque

A

true

90
Q

How can a muscle become a PURE abductor?

A

if you neutralize rotation

91
Q

A person with Trendelenburg gait will compensate by side bending which way, towards the impaired glut med or away from impaired glut med?

A

towards impaired glut med

92
Q

For every lb you weigh, how much does it take for gluteus medius to stabilize your hip joint?

A

it takes twice that what you weight for glut med to stabilize your hip joint
- JRF is three times that weight

93
Q

For each 1 lb. reduction in body weight, how much “weight” does that unload on the hip?

A

3 lbs

94
Q

When is abductor torque maximized?

A

when limb is at neutral or even slightly adducted (the muscle length is at its longest here)

95
Q

What are the primary ERs of the hip?

A

gluteus max and the short ERs (piriformis, gemellae, obturator internus, and quadratus femoris)

96
Q

What muscle is strained in a groin pull?

A

adductor longus, by trying to decelerate ER

97
Q

What arthrokinematics occur with hip flexion? What’s the direction of the spin?

A

rolls anterior and superior, slides posterior and inferior (femur spins posterior)

98
Q

“Femur spinning anterior” describes what motion?

A

hip extension

99
Q

What can the superior fibers of glut max do?

A

hip ER

100
Q

What fibers of glut med are secondary hip extensors?

A

posterior fibers do hip extension

101
Q

What do the posterior fibers of glut min do? What do the posterior fibers of glut med do?

A

posterior glut med = hip extension

posterior glut min = hip ER

102
Q

What are your primary and secondary abductors of the hip?

A
primary = GLUT MED, glut min, TFL
secondary = piriformis, sartorious