Introduction to Kinesiology

Question 1

What is biomechanics?

Answer 1

A discipline that uses principles of physics to quantitatively study how forces interact within a living body

Question 2

What is physiology?

Answer 2

The biologic study of living organisms

Question 3

What is Kinematics?

Answer 3

A branch of mechanics that describes the motion of a body, without regard to the forces or torques that may produce the motion

Question 4

Two Types of Motions

Answer 4

1) Translation

2) Rotation

Question 5

What is translation?

Answer 5

A linear motion in which all parts of a rigid body move parallel to and in the same direction as every other part of the body

Question 6

Translation can occur in either a ___ line or a _____ line.

Answer 6

Straight (rectineal)

Curved (curvilinear)

Question 7

What is rotation?

Answer 7

A motion in which an assumed rigid body moves in a circular path around some pivot point

Question 8

A person’s COG _____ through space, and is powered by muscles that ____ the limbs.

Answer 8

translate

rotate

Question 9

What is the pivot point for angular motion of the body or body parts called? (the point where motion of the rotating body is zero)

Answer 9

Axis of Rotation (AoR)

Question 10

Active vs. Passive Movements

Answer 10

Active Movements are caused by stimulated muscle, such as when lifting a glass of water toward the mouth.

Passive Movements are caused by sources other than active muscle contraction, such as a push from another person, the pull of gravity, etc.

Question 11

What is osteokinematics?

Answer 11

motion of bones relative to three cardinal planes of body

Question 12

The axis of rotation is typically located through the _____ member of the joint.

Answer 12

Convex

Question 13

Degrees of Freedom

Answer 13

The number of independent directions of movements allowed at a joint

The number of permitted planes of angular motion at a joint

Question 14

A joint can have up to how many degrees of angular freedom and why?

Answer 14

3, corresponding to the 3 cardinal planes

Question 15

How many degrees of freedom does the shoulder have? Wrist? Elbow? Explain why for each

Answer 15

Shoulder: 3 (one for each plane)
Wrist: 2 (rotation within sagittal and frontal planes)
Elbow: 1

Question 16

What are accessory movements?

Answer 16

Slight, passive, nonvolitional movements allowed in most joints that are used to test the health of the joint (aka joint play)

Question 17

What may excessive joint translation (or joint play) indicate?

Answer 17

ligamentous injury or abnormal laxity

Question 18

What may a reduction in joint translation (or joint play) indicate?

Answer 18

pathologic stiffness within surrounding periarticular connective tissues

Question 19

Describe a proximal-on-distal segment and give an example

Answer 19

The proximal segment can rotate against the relatively fixed distal segment

Knee Flexion Example:
LAQ - The femur is fixed and the tibia rotates against it. Therefore it is known as tibial-on-femoral

Question 20

Describe a distal-on-proximal segment and give an example

Answer 20

The distal segment can rotate against the relatively fixed proximal segment

Knee Flexion Example:
Squat - The tibia is fixed and the femur rotates against it. Therefore it is known as femoral-on-tibial

Question 21

What is Arthrokinematics?

Answer 21

The motion that occurs between the articular surfaces of joints

Question 22

What are the 3 fundamental movements that exist between curved joint surfaces?

Answer 22

1) Roll
2) Slide
3) Spin

Question 23

Describe Rolling

Answer 23

Multiple points along one rotating articular surface contact multiple points on another articular surface

Question 24

Describe Sliding

Answer 24

A single point on one articular surface contacts multiple points on another articular surface

Question 25

Describe Spinning

Answer 25

A single point on one articular surface rotates on a single point on another articular surface

Question 26

In a convex-on-concave movement what direction does the convex segment roll? What way does it slide?

Answer 26

Roll occurs in the direction of the movement and slide occur in the opposite direction of the movement

Question 27

In a concave-on-convex movement what direction does the concave segment roll? What way does it slide?

Answer 27

Roll and slide both occur in the same direction of the movement

Question 28

What is a close-packed position?

Answer 28

The unique position of most joints where the articular surfaces are most congruent and the ligaments are maximally taut

Question 29

What is a loose-packed position?

Answer 29

The positions of most synovial joints of the body in which the articular surfaces are least congruent and the ligaments are slackened, which allows for an increase in accessory movements

Question 30

What is kinetics?

Answer 30

A branch of the study of mechanics that describes effect of forces and torques on the body

Question 31

What is a force?

Answer 31

push or pull that produces, arrests, or modifies a movement

Question 32

Force = ?

Answer 32

F = (m) that receives the push or pull multiplied by acceleration (a) of mass

Question 33

Force that acts on a body is often referred to generically as a ____.

Answer 33

Load

Question 34

7 Types of Loads Applied to the MSK System

Answer 34

1) Unloaded
2) Tension
3) Compression
4) Bending
5) Shear
6) Torsion
7) Combined Loading

Question 35

Stress vs. Strain

Answer 35

Stress is the force generated as a tissue resists deformation, divided by its cross-sectional area
Strain is the ratio of a tissue’s deformed length to its original length

Question 36

Define Viscoelasticity

Answer 36

The property of a material expressed by a changing stress-strain relationship over time

Question 37

What is creep?

Answer 37

A progressive strain of a material when exposed to a constant load over time

Question 38

Creep is reversible while ___ deformation is not

Answer 38

Plastic

Question 39

What phenomenon explains why a person is taller in the morning than they are at night?

Answer 39

Creep of the IVD’s

Question 40

Describe how the stress-strain curve changes as the rate of loading changes

Answer 40

The slope of stress-strain curve increases when the rate of loading increases

Question 41

2 Sets of Forces that act on the musculoskeletal system

Answer 41

1) Internal

2) External

Question 42

Internal vs. External Forces

Answer 42

Internal Forces are either actively or passively produced from structures located within body
External Forces are produced by forces acting from outside body

Question 43

Torque = ?

Answer 43

Force multiplied by the moment arm produced

Question 44

Force acting without a moment arm can push and pull an object generally in a ____ fashion, whereas torque ____ an object around AoR

Answer 44

Linear

Rotates

Question 45

2 Requirements of a muscle to be able to produce torque

Answer 45

1) It must produce a force in the plane perpendicular to AoR of interest
2) It must act with associated moment arm distance > zero

Question 46

What is the relationship between internal and external torque during a isometric contraction?

Answer 46

internal torque = external torque

Question 47

What is the relationship between internal and external torque during a concentric contraction?

Answer 47

internal torque > external torque

Question 48

What is the relationship between internal and external torque during a eccentric contraction?

Answer 48

external torque > internal torque