Midterm Flashcards
1
Q
What is kinesiology?
A
The study of human movement
2
Q
What is kinematic?
A
A branch of mechanics that describes motion of a body in space without regard to forces or torques
3
Q
What are the two types of motion?
A
- Translation
- Rotation
4
Q
What is translation motion?
A
Linear motion - all parts move in a straight line
5
Q
What is rotation motion?
A
Angular motion - body spins about an axis
6
Q
In the human body, what translates through space during movements?
A
The center of mass (where mass is exactly centered)
7
Q
Where is the center of mass located?
A
In front of S2 sacral segment, near bellybutton
8
Q
How do muscles create angular movements?
A
Muscles rotate the limb to create angular movement of joint
9
Q
What is a pivot point?
A
The axis of rotation, point where motion of rotating body is zero
10
Q
How can movement of body be describes?
A
Active or passive
11
Q
What is active movement?
A
Movement that is caused by stimulated muscle contractions
Volitional (conscious) control
12
Q
What is passive movement?
A
Movement that is caused by other sources like external forces (gravity, push/pull) or tension in stretched connective tissue (internal forces)
13
Q
What is osteokinematics?
A
The motion of bones relative to the 3 cardinal planes
14
Q
What are the three cardinal planes?
A
- Sagittal
- frontal
- transverse
15
Q
What are the planes of motion in relationship to? (Reference frame)
A
Anatomical position
16
Q
What does the sagittal plane divide? What is its axis?
A
- Divides the body from left to right segments
- medial to lateral axis
17
Q
What does the frontal plane divide? What is its axis?
A
- divides body from left to right
- anterior-posterior axis
18
Q
What does the transverse plane divide? What is its axis?
A
- divides the body into top and bottom segments
- vertical axis
19
Q
What is the axis of rotation?
A
point at which the bones rotate around the joint and perpendicular to the plane
20
Q
Which partner does the axis of rotation pass through?
A
Convex partner
21
Q
What motions typically occur in sagittal plane?
A
flexion, extension, dorsiflexion, plantarflexion
22
Q
What motions occur in the frontal plane?
A
abduction, adduction, lateral flexion
23
Q
What motions occur in the horizontal plane?
A
medial (internal) rotation, lateral (external) rotation
24
Q
What are degrees of freedom and how many are allowed at a joint?
A
- the number of independent directions of movements allowed at a joint
- joints can have up to 3 degrees of freedom, in all 3 planes of motion
25
What are accessory movements? In what directions to they occur?
- slight passive translatory movement of the bones in the joint
- occurs in A/P, M/L, S/I directions
26
What is proximal on distal joint movement?
- proximal segment rotates on fixed distal segment
- ex. squatting; push-up
27
What is distal on proximal joint movement?
- distal joint segment rotates on fixed proximal segment
- ex. knee extension while sitting; elbow flexion
28
Anatomical position
generally agreed upon reference position of the body used to describe location and movement of its parts
- a person standing full upright, looking forward, arms resting by side, forearms supinated
29
What is external force?
push or pull produced by sources located outside the body
- gravity, physical contact
30
What is a segment?
any portion of the body or limb
31
What is arthrokinematics?
the motion that occurs between articular surfaces of joints
32
What are the fundamental movements between joint surfaces?
- roll
- spin
- slide
33
definition of roll
when multiple points along one rotating articular surface contact multiple points on another surface
- ex. like a tire moving on the ground
34
definition of slide
a single point on one articular surface contacts multiple points on another articular surface
- ex. a tire (non-rotating) skids across a stretch of pavement
35
definition of spin
a single point on one articular surface rotates on a single point of another articular surface
- ex. a toy top spinning
36
When does the roll and slide occur in the same direction?
concave on convex
37
What is an example of same roll and slide direction?
elbow flexion (the concave olecranon of the ulna moves on the convex humerus)
38
When does the roll ad side occur in the opposite direction?
convex on concave
39
What is an example of opposite roll and slide direction?
shoulder abduction (the convex head of humerus moves in concave glenoid fossa)
40
When does spinning arthrokinematics occur?
when the longitudinal axis of the moving bones intersects the surface of its partner at a right angle
41
What are examples of spin arthrokinematics?
- internal and external rotation of the humerus at 90 deg. abduction
- ball and socket joints
- forearm pronation at the radiohumeral joint
42
When are all 3 arthrokinematics motions combines?
- when the joint will slightly spin to lock the joint
- flexion/extension of the knee, you get a spin of the tibia to lock the joint
43
What is a closed packed position of a joint?
the position of max congruency, the articular surfaces are tightly packed together
44
When does a closed packed position occur?
at the end or near the end of a range of motion
45
How many positions in a joint are close packed?
one
46
What is a loose packed position of a joint?
- all other positions of a joint other than close packed
- the ligaments are slackened and allow for accessory movement
47
When does loose packed position occur?
in midrange of range of motion
48
What is resting position of a joint?
- most loose-packed position
- most comfortable when joints are injured or swollen
- somewhere in midrange ROM
49
What is kinetics?
a branch of mechanics that describes the effect of forces on the body
50
What is a force?
a push or pull that can produce, stop, or modify a movement
51
What is force also known as when acting on the body?
a load
52
What is torque?
force around an axis
53
What are example of force?
- tension
- compression
- bending
- shear
- torsion
- combined
- unloaded
54
Difference between health and damaged tissues in terms of force
- healthy tissues can withstand force and maintain their structure
- damaged or weak tissues are more susceptible to loads and strains
55
What is the ratio of stress/strain?
stiffness
56
What is the elastic region of stress strain curve?
linear region where there is still stretching, but it isn't breaking
57
What is the plastic region of stress strain curve?
nonlinear region where deformation can occur
- tissue can reach failure point and tear/break
58
What is the yield point of stress strain curve?
- complete failure of tissue
- the tissue doesn't return to normal and is deformed
59
What is viscoelasticity?
property of material that changes along the stress strain curve as a function of time
- ex. taffy, slowly stretch, if you pull very quickly it won't do anything
60
definition of creep
a progressive strain of a material when exposed to a constant load over time and eventually can break
61
How does rate of loading impact stress strain curve?
if you're loading something very fast this has more resistance to deformation
62
explain the stress strain curve with examples
- taffy example: if you slowly start to stretch taffy, you are able to pull on it and create a bridge of taffy between your two hands. as you pull your hands apart, this is the plastic elastic region. when the bridge of taffy gets very thin, you enter the plastic region where the taffy is likely to break. finally you hit the yield point where the bridge of the taffy breaks and you're left with taffy split in half
63
What are internal forces?
forces produced from structures within the body and may be active or passive
64
What are external forces?
forces produced by sources outside of the body
65
What are examples of active and passive internal forces?
- active forces are muscles
- passive are connective tissue (usually restrain motion)
66
What are examples of external forces?
- gravity (wind resistance, friction)
- physical contact (weight on something)
67
What is a free body diagram?
an illustration of forces acting on a segment of the body
68
What are components of a free body diagram?
- vector
- point of application
- angle of insertion
69
What is the most effective angle to move an object?
90 degrees
70
What is a vector?
an arrow that depicts both magnitude and direction
71
What is point of application?
where the base of the arrow contacts the body (where muscle inserts into bone)
72
What is angle of insertion?
angle between the tendon of the muscle and the bone insertion
73
What is static linear equilibrium?
the sum of all forces acting on the segment is zero because forces are balanced
74
How many times greater is internal than external force and what does this mean?
- 3x greater
- to hold your forearm at 90 deg., your bicep has to work 3x as hard as gravity
75
What is the equation for work and torque
work = force x distance
torque = force x resistance
76
What is a concentric muscle activation?
occurs as a muscle produces a pulling force as it contracts (shortens) usually an acceleration
77
What is an isometric muscle activation?
occurs when a muscle is producing a pulling force when maintaining a constant length
78
What is an eccentric muscle activation?
- occurs as a muscle produces a pulling force as it is being elongated by a more dominant force (lengthening)
- usually a deceleration
79
What plane does gravity minimize?
transverse plane
80
Agonist
muscle of muscle group that is most closely related to the initiation and execution of a particular movement
81
antagonist
muscle or group that is considered to have opposite action of agonist
82
synergist
- muscle that cooperate during a movement
- some muscles can neutralize unwanted movement to create a particular movement
- helps, holds stable
83
force couple
when 2 or more muscles simultaneously produce forces in different linear directions and results in rotary direction
84
example of force couple
- upper and middle traps with serratus anterior working on scapula to pull into upward rotation
- upper trap pulls up on acromion, middle pulls down on spine, serratus pulls on inferior angle
85
What is a lever? what are the components?
- machine that has a rod suspended across a pivot point; converts linear force into rotary torque
- has axis, muscle force/effort resistance (AER)
86
What is a first class lever? Example?
has axis of rotation between the muscle effort and resistance
ex. seesaw
87
What is a second class lever? Example?
has an axis of rotation at one end and resistance in the middle
ex. going on tip toes
88
What is a third class lever? Example?
has an axis of rotation at one end and effort in the middle
ex. biceps curl
89
What is mechanical advantage?
the ratio of the internal moment arm to the external moment arm (leverage)
90
What are the acronyms for levers?
- EAR
- ARE
- REA
91
Line of force
direction and orientation of a muscle force
92
moment arm
perpendicular distance between axis of rotation and the line of force
93
stiffness
ratio of stress (force) to strain (elongation) within an elastic material
94
contrast the fundamental difference between kinematics and kinetics
- kinematics describes motion but doesn't look at or include force/torque
- kinetics describes motion by examining the impact of the torque/force on the body
95
contrast the difference between force and torque
(use each term to describe an aspect of a muscle's contraction relative to a joint)
- force is a push or a pull in a straight line that can stop or start a motion
- torque is a force that occurs in a rotation around an axis
- a contraction force produced by the elbow flexor muscles can create compression within the elbow joint. the torque produced by the elbow flexor muscles can produce angular acceleration of the elbow which brings your hand to your mouth
96
define and contrast internal and external torque with an example
- internal torque is a torque produced around a joint by an internal force (muscle contracting)
- external torque is a torque produced around a joint caused by an external force (gravity)
- when opposing internal and external torques about a joint are equal, the joint is often described as being in static rotary equilibrium. if the internal and external torques were not equal, the joint would accelerate in the direction of the larger torque
97
