Slide deck 1

define Kinesiology

study of human movement

Kinematics is the

appearance of motion

“description of motion”

Kinetics is

forces associated with motion

kinetics is affected by

anthropometric factors

Types of motion in Kinetics

Linear/translational

angular

Linear/translatory motion

all points on a rigid move the same distance and direction

“one point tracking as it moves over time”

Angular

axis ridge body rotates around

Translatory motion

all points on a rigid object move the same distance and direction

“one point tracking as it moves over time”

Rectilinear motion

straight line

Curvilinear motion

curved line

Angular motion

movement of a rigid body in circular path around some pivot point

“ clockwise or counterclockwise”

Angular motion

In a _________

Around a ______

Described as __________ or __________

Measured in _______

1. plane

2. axis

3. clockwise or counterclockwise

4. degrees

Frontal plane is what axis

AP

What occurs in Frontal plane- AP axis

ABD/ADD + inversion and eversion

Sagittal is in what axis

medial/ lateral

What occurs in the Sagittal- med/lateral axis

flexion/extension + dorsi/plantar flexion

Transverse is what axis

superior/inferior axis

What occurs in transverse- superior/inferior axis

rotations

Human motion

the rotation around a joint or senior of joints → That collectively produce translation of the entire body through space

“Center of mass”

ALL MASS EQUALLY SPREAD AROUND”

Osteokinematics

motion of bones

IN a plane

AROUND an axis

“axis perp to plane”

denote motion

ing

denote static position

ed

Degrees of freedom

number of planes of motion that are under volitional control at a given joint

closed-chain

proximal segment can rotate against the relatively fixed distal segment

“femur to tib”

open-chain

distal segment can rotate against the relatively fixed proximal segment

“tib to femur”

Distal on proximal → DISTAL end is ________ to move

FREE

Proximal on distal → DISTAL end is _________ in

FIXED

Close-packed position

the least amount of accessory/joint play in motion (CPP)

Loose-packed position

created amount of accessory/joint play motion

Arthrokinematics

“magic school bus”

motion in joint as bone is moving

Component motion

primary movement that occurs within a joint as a result of an active voluntary movement

Joint play

small, involuntary movements that occur within a join when an external force is applied

• result of external forces

Roll

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

ex: multi on femur → tibia

Slide

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

ex: one point on femur → multi point on tibia

Spin

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

ex: one point → one point

During which of the following motions do multiple pints on the convex surface contact multiple points on the flat/concave surface?

roll

During which of the following motion does a single point on the convex surface repeatedly contact multiple points on the flat/concave surface?

slide

Kaltenborn’s Rule

conVEX on conCAVE

slide is in opposite direction osteokinematic motion

roll is always in direction of osteokinematic motion

roll and slide are in opposite directions

Slide is in the __________- direction of osteokinematic motion

opposite

Roll always is _________ direction of osteokinematic motion

IN

Roll and slide are in _____________- directions

opposite

Important to figure out:

1. which bone is _________

2. what does the bone _____ like

stable

look

Femur is an example of

CV

Tibia is example of

CC

When ConCAVE member of the joint is moving on the conVEX

roll and slide are in the same direction

ex: tibia posterior → femur posteriorly

Screw home mechanism at knee is an example of spin because

terminal knee extension, tibia externally rotates to “lock” knee into extension (distal end free)

femur internally rotates on tibia (distal end fixed)

Force

a push or pull that can cause stop or alter movement

Tension forces

force that pulls the sides of the material apart

compression forces

force that pushes the sides of the material together

Bending forces

force that lengthens one side of the material while shortening the opposite

shear forces

force produced as two compressed objects slide past each other in opposite directions

torsion force

rotational movements

strain is

how much material is deforming

nonlinear (toe) region

taking up slack

linear region ( elastic region)

1:1 ratio

everything goes back to original shape

Yield point

stretch beyond physiological range

Plastic region

microscopic failure

don’t get all energy back

Ultimate failure point

loose all ability to hold stress

The strain-stress curve doesn’t account for

time

Viscoelasticity

amount of deformation a tissue undergoes with a given level of stress/force is time dependent

creep

tendency of a solid material to move slowly or deform under the influence of mechanical stress

• progressive strain with constant load/stress over time

• can be reversible and also non-reversible

Internal forces

inside human body

External forces

outside the body

• mainly gravity

arrows are

vectors

• point of application

• orientation: angle of lever

• magnitude: length

  • direction: arrow head

types of motion created by force

translation

rotation/force

translation

motion not around an axis

rotation/torque

motion occurring at a point away from the axis of rotation of the joint

In order to have a Torque

force must be applied at a point away from the axis of rotation

Moment arm

perpendicular distance between the axis of rotation of the joint and the point of force application

torque =

F x d

equilibrium is

Ti = Te

one must be larger to balance it out

isometric

constant length while producing a pulling force

Internal force = external force

Concentric

muscle shortening

internal torque moving toward it

internal torque at joint exceeds opposing external torque

Eccentric

muscle lengthens

external torque is larger

internal torque is less than opposing external torque

agonist

most directly related

Antagonist

opposite to the movement

synergists

work together

Class 1

axis is in between external and internal force

seesaw

Class 2

the axis sits on one end

the external force is larger than the internal force and sits in the center

the internal force is small and is on the opposite end

“wheel barrel” “plantar flexion”

Class 3

Axis is on one end

internal force is large and in the center

the external force is on the opposite end

“pretty much all human bodies”

Which class lever is the least mechanically efficient

class 3 levers