Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PT 711-Kinesiology > Exam 2 > Flashcards

Exam 2 Flashcards

(100 cards)

Start Studying
1
Q

motor units

A
  • single motor neuron, junctions, and fibers it controls

- can contain several axons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how many fibers can each axon innervate?

A

5-2000 fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

parallel muscle fibers have___

A

greater range of motion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

most common type of muscle

A

bipennate

-fibers on both sides of tendon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

characteristics of oblique muscle fiber orientation:

A
  • shorter
  • more numerous
  • greater strength
  • shorter ROM
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

isotonic:

A
  • constant load

- fibers change length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

isokinetic:

A
  • fixed speed

- variable accommodating resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

isokinetic accommodates to:

A

ROM
pain
fatigue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

factors influencing motion

A
  1. PROM
  2. Fiber length
  3. Relationship of length and moment arm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

effect of moment arm length and ROM

A

the shorter the moment arm the great the distal part moves through an arc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

effect of moment arm on strength of muscle

A

longer moment arm as greater torque which equals more strength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

greatest tension in the muscle can develop when:

A

there is the most cross bridges which is at resting length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

faster contraction (concentric) =

A

lower force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

faster contraction (eccentric)=

A

higher force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Henneman Size Principle

A

smaller motor units are recruited first

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

decreased activity produces most atrophy in:

A

antigravity muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

shortened muscle position from inactivity increases rate of____

A

protein loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

lost muscle mass in replaced by:

A
  • adipose tissue
  • fibrous connective tissue
  • called senile sarcopenia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

cross-sections of which type of muscle decrease faster from aging?

A

type II

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

tendon and ligament structure

A
  • dense regular connective tissue
  • mostly type I collagen and water
  • some type III collagen
  • very little elastin in tendons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

proteoglycans in tendon/ligament

A

tendon has less proteoglycans than ligament

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

elastic region of tendon/ligament

A

-crip straightening by collagen sliding past each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

substance tear

A

middle of the tendon/ligament

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

avulsion

A

tendon/liagment pulls piece of bone out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
ligament failure more affected by:
age than rate of action
26
increased rate of force in ligament/tendon
-increased brittle behavior (failure liekely to occur by rupture)
27
lower rate of force on ligament/tendon
less brittle nature so avulsion more likely
28
start to get tissue changes at temperature
37-40 degrees celcius | -above 60 celcius results in collagen shrinkage
29
effect of maturation/aging on tendon/ligament
- decrease collagen and GAG - increased elastin - decreased crimp angle (reduced stiffness)
30
changes in tendon from aging can be minimized by:
low to moderate intensity resistance exercise
31
hormones that reduce strength of connective tissue
- adrenocorticotropic hormone - cortisone - relaxin - lower GAG content - Reduce collagen synthesis type I
32
better to be in ___ position when immobilized
lengthened
33
best for tendon stimulation:
low to moderate tension
34
thickest articular cartilage in the body:
lunate surface
35
purpouse of neck of femur
- greater lever arm and angle for the least amount of energy expended - gets the shaft farther from the body to avoid impingement
36
bowing of femur
- compresses posterior | - tension anterior
37
what reduces the angle of inclination after birth?
walking
38
angle of inclination at birth
140-150 degrees | normal is 125 degrees
39
coxa valga
angle of inclination of 140 degrees - associated with genu varum - often leads to dislocation - decreases bending moment arm - less shear force aross femoral head - increased function length of hip abductors - decreased moment arm for abductor force
40
coxa vara
angle of inclination of 105 degrees - associated with genu valgum - increase moment arm for abductors - may increase stability - increased bending moment arm which increases shearing across femoral neck - shortens functional length of abductors
41
which is more stable, coxa valga or vara?
coxa vara is more stable than valga
42
excessive femoral anteversion
- greater than 20 degrees | - usually causes toeing in for better advantage of hip abductors
43
acetabular anteversion
- 20 degrees - less stable - dislocate anterior
44
posterior hip capsule resists
hip flexion | hip IR
45
what resists hip IR
- external rotators - ischiofemoral ligament - posterior capsule
46
what would decreased center edge angle do?
superior dislocation
47
taut tissue in hip flexion (knee ext)
hamstrings
48
taut tissues in hip flexion knee flex.
inferior and posterior capsule | -gluteus maximus
49
taut tissues in hip extension (knee ext.)
``` iliofemoral ligament -some pubofemoral -some ischiofemorl al -some psoas major ```
50
taut tissues in hip extension (knee flex.)
rectus femoris
51
taut tissues in hip abduction
- pubofemoral ligament | - adductor muscles
52
taut tissues in hip adduction
- superior fibers of ischiofemoral ligament - iliotibial band - tensor fasciae latae - gluteus medius
53
taut tissue in hip IR
- ischiofemoral ligament | - external rotator muscles : piriformis gluteus maximus
54
taut tissue in hip ER
- iliofemoral and pubofemoral ligaments | - internal rotator muscles: tensor fasciae latae, gluteus minimus
55
closed packed position for the hip
- full ext - slight IR - slight abd
56
loose-packed position for the hip
30 degrees flexion and abduction, slight ER
57
hip capsular pattern
medial rotation limited more than flexion and abduction | -no limitation in lateral rotation or adduction
58
rotation of hip during gait
- forward leg has hip ER | - following leg has hip IR
59
normal hip flexion
120
60
normal hip extension
20
61
normal hip abduction
40
62
normal hip adduction
25
63
normal hip internal rotation
35
64
normal hip external rotation
45
65
normal hip inclination
125
66
normal hip anteversion
15
67
normal knee flexion
145
68
normal knee extension
0
69
normal knee IR/ER
45 together | -more ER than IR
70
normal knee Q-angle
170-175
71
wolf's law
increased bone loading = increased bone strengthening
72
factors that influence muscle strength
- pCSA (size) - stretch - moment arm - contraction velocity - motor unit recruitment
73
effect of aging on muscle
- loss of skeletal muscle mass from inactivity - replaced as adipose tissue - reduction in myofibers - slower circulatory supply - decreased capacity to recover from exercise - decrease of elasticity
74
strap muscles
rectus abdominis | sternocleidomastoid
75
fusiform muscles
biceps brachii | brachialis
76
rhomboidal muscles
- rhomboids | - pronator quadratus
77
triangular muscles
pectoralis major
78
unipennate muscle
-all of the muscle fibers are on the same side of the tendon
79
bipennate muscle
the most common type, has muscle fibers on both sides of the tendon
80
multipennate muscle
has branches of the tendon within the muscle
81
oblique muscle fibers
- shorter but more numerous - greater strength potential - shorter ROM
82
prolonged muscle shortening
- loss of sarcomeres | - may depend on immobilization and specific muscles
83
a faster concentric contraction has a
lower force
84
a faster eccentric contraction has a
higher force
85
effect of age on ligament/tendon
- decrease collagen and GAG - increased elastin - decreased crimp angle - reduced stiffness
86
effect of inactivity on muscle
- atrophy - decreased strength (especially in shortened position) - transition type I to type II
87
lose packed position of knee
25 degrees flexed
88
close-packed position of knee
full extension and ER
89
MCL (posterior-medial capsule
1. resists valgus 2. resists knee extension 3. resists extemes of axial rotation (especially ER)
90
LCL
1. resists varus 2. resists knee extension 3. resists extremes of axial rotation
91
posterior capsule
1. resists knee extension 2. oblique popliteal ligament resists knee ER 3. posterio-lateral capsule resists varus
92
ACL
1. most fibers resist extension (anterior translation of tibia) 2. resists extremes of varus, valgus, and axial rotation
93
PCL
1. most fibers resist knee flexion (post. translation of tibia) 2. resists extremes of varus, valgus, and axial rotation
94
what extensor has greatest pCSA
Gluteus maximus | adductor magnus
95
abductor with the longest moment arm
gluteus medius
96
hip abductor is the strongest with
extension; stabilizing during gait while you swing other leg through
97
external rotator that has a small moment arm
obturator externus
98
Factors guiding screw-home mechanism
1. shape of medial femoral condyle 2. tension in ACL 3. Lateral pull of quadriceps
99
menisci move __ with extension
anterior
100
menisci move ___ with flexion
posterior

PT 711-Kinesiology (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions