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Flashcards in BIOMECHANICS 1 Deck (51)
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1
Q

Biomechanics

A

The use of math and physical principles to study and understand movement

2
Q

Kinematics

A

The study of movement without regard to the forces that cause that movement
i.e. How far, how much, how fast

3
Q

Kinetics

A

The study of forces causing a movement i.e. muscle forces, gravity

4
Q

Movement is in ____ and about _____

A

a plane of motion and about an axis of motion

5
Q

Which movements take place about the anteroposterior axis

A

abduction/adduction

6
Q

Which movements take place about the mediolateral axis?

A

Flexion extension

7
Q

Which movements take place about the longitudinal axis

A

Rotation
Supination
Pronation

8
Q

Which axis of rotation corresponds with the frontal plane of motion

A

Anteroposterior

9
Q

Which axis of rotation corresponds with the sagittal plane of motion

A

Mediolateral

10
Q

Which axis of rotation corresponds with the transverse plane of motion

A

longitudinal

11
Q

Newtons 3 laws?

A
  1. motion stays in motion unless an unbalanced, external force is applied to it
  2. F = ma
  3. For every action there is an reaction of equal magnitude and opposite in direction
12
Q

Arthrokinematics

A

movement between joint surfaces

13
Q

Osteokinematics

A

movement between bones

14
Q

Kinematic chain

A

linkage of rigid bodies

15
Q

Why is closed chain greater risk of injury

A
  • because of degrees of freedom

- Closed chain removes degrees of freedom making it harder to change positions

16
Q

A force is any..

A

push or pull

17
Q

How much an object deforms is relative to..

A

how much stress or force is put on it

18
Q

Stress =

A

force

19
Q

Strain =

A

length

20
Q

What changes a stress straiin curve

A

different material properties

21
Q

What occurs in the plastic zone of the stress strain relationship

A

You get disproportionate change in length for given change in force - greater change in length for given force

22
Q

What does the slope of the stress strain curve represent

A

stiffness

23
Q

In the envelope of function what are the 3 zones and the x and y axis

A
x - frequency 
y - load 
Zones: 
1. Homeostasis (ADLs) 
2. Supraphysiological overload 
3. Structural failure
24
Q

Overstepping you maximum capacity to adapt will result in…

A
  1. pain during your effort
  2. pain after
  3. morning stiffness
25
Q

IN the body, do different tissue types have different stress strain responses

A

yes - 3 different reactions to same strain

26
Q

what are some reasons the same tissue type undergoing the same stress may tear in different situations

A
  • Temperature
  • Fatigue
  • Direction of force
  • Previous injury or microtears
  • Warm-up
  • Age
27
Q

How does emphysema relate to the stress strain relationship

A

emphysema - lung tissue no functioning as it should. for a given force the lungs of healthy patients stretch more than those of patients with emphysema. Greater energy expenditure to get the same stretch

28
Q

When does isometric contractions occur

A

when force is generated by the muscle but is equivalent to external resistance
Force = resistance or equal moments

29
Q

The relationship between ____ and ____ will dictate the resultant linear/angular motion of a segment

A

internal forces/moments and external forces/moments

30
Q

are all muscles always acting throughout the whole movment

A

no may contract eccentrically, concentrically or not at all

31
Q

What are external forces

A

forces acting outside the body

32
Q

What is a moment

A

the angular equivalent of force - any push or pull that makes a rotational force

33
Q

equation for moment

A

M = f x d

34
Q

What is the moment arm

A

the perpendicular distance from the line of action of the force application to the axis of rotation

35
Q

Moments cause ____ rotation due to ____ force production when one end of a linkage is fixed

A

angular

linear

36
Q

What are the two types of linear forces (that we are concerned of in this class)

A

Shear force

Compression force

37
Q

Shear force occurs ___ to segment

A

perpendicular

38
Q

Compression forces occurs ____ to segment

A

parallel

39
Q

What is newtons second law of angular motion - include equation

A

An object of inertia will angularly accelerate proportional to the Moment applied to it, and inversely to its inertia
Sum(F x d) = I x a

40
Q

Inertia is ..

A

the angular component of mass

41
Q

Biomechanically, the magnitude of the moment is mainly dependent upon the…

A

joint angle

42
Q

The joint angle changes two things

A

effect on moment arm

effect on force generation (actin myosin overlap)

43
Q

1st class level

A

Muscle force and resistance force act on opposite sides of the axis

44
Q

What is an example of a first class lever

A

occipital condyles in head

45
Q

2nd class lever

A

Resistance force is between the muscle force and the axis

46
Q

What is an example of a 2nd class lever

A

metatarsal joint

47
Q

3rd class lever

A

Muscle force is between the axis of rotation and the resistance force

48
Q

example of 3rd class lever

A

elbow

49
Q

Most anatomical levers are ___

A

3rd class levers

50
Q

What is mechanical advantage

A

the ratio of the muscle moment arm to the resistance moment arm

51
Q

What is the equation for Mechanical advantage

A

MA = moment arm muscle/moment arm resistance