Biomechanics Exam 1

human movement

• movement or motion; involves a change in place, position or posture relative to some point in environment

movement

interact with our environment; walking, strengthen muscle, high jump, stretch injured joint

biomechanics

study of structure and function of biological systems by means of the methods of mechanics

ergonomics

good posture

human motion

walk/running

qualitative

• non-numeric

• based on direct observation

• equipment not necessary

• based on temporal and spatial aspect

quantitative

• numeric

• based on collected data

• equipment necessary

• baed on forces as well as temporal and spatial aspects

qualitative example

he malfunctioned

quantitative example

he missed by 15 feet

linear motion

motion along a straight or curved path

angular motion

motion about a point

kinematics

• concerns spatial and temporal aspects of motion

• description of how fast an object is moving, how high it goes, or how far it travels

kinetics

• concerns the force acting on a body or any object

• examines forces causing a movement

• forces cannot be seen, but their effects can be observed

static

• examines systems not. moving/moving at constant speed

• equilibrium: no acceleration

static example

space ship is gliding through space

dynamics

examines systems that are being accelerated

dynamic example

sprint

medial

closer to midline

lateral

away from midline

proximal

closer to reference point

distal

away from reference point

superior

above reference point

inferior

below reference point

anterior

infront of reference point

posterior

behind reference point

superficial

close to surface

deep

more internal

flexion

decreasing join angle

extension

increasing joint angle

hyperflexion

flexion beyond normal range

hyperextension

extension beyond normal range

abduction

moving away from midline

adduction

moving toward midline

hyperabduction

abduction past 180 degrees point (head)

hyperadduction

adduction past 0 degrees point

medial rotation

internal

lateral roation

external

horizontal adduction

combination of flexion and adduction

horizontal abduction

combination of extension and abduction

lateral flexion

head or trunk only

• head tilts sideways

circumduction

movement in a conic fashion (circular motion)

supination

turn palms upward

pronation

turn palms down

radial flexion

bending wrist towards the thumb

ulnar flexion

bending wrist towards pinky

plantar flexion

increase angle between foot and shank

• point toes down

dorsiflexion

decrease angle between foot and shank

• point toes up

inversion

lift medial edge of foot

eversion

lift lateral edge of foot

axis

imaginary line in which rotation occurs

plane

2D surface in which lines connect at 2 points on the surface

sagittal plane

divides body left and right

• straight down the center of your body

frontal plane

divides the body posterior and anterior

transverse plane

divides body superior and inferior

• divides body at the midpoint horizontally

cardinal plane

passes through the midpoint of the body

mediolateral axes

• transverse

• perpendicular to sagittal plane

anteroposterior axis

perpendicular to frontal plane

longitudinal/ superoinefeirior axis

perpendicular to transverse plane

degree of freedom

number of planes in which the joint has ability to move

uniaxial

1 degree of freedom

biaxial

2 degrees of freedom

triaxial

3 degrees of freedom

reference system

• necessary for accurate observation and description

• fundamental and anatomical positions

axes

imaginary lines that intersect at right angles

origin

point of intersection of axes

relative

segment movement described relative to the adjacent segment

absolute

axes intersect in the center of a joint

anthropometry

studies the measurements of the body and body segments in terms of high, weight, volume, length

free-body diagram

• simplified representation of the system free of the movement environment

function of bones

1. support

2. attachment sites

3. leverage

4. protection/ mineral storage

support

structure of body and maintain posture

attachment sites

tendons, muscles, ligaments

leverage

system of levers and axes

bone

matrix of inorganic salts and collagen

osteocytes

bone cells

osteoblasts

cells that create bone

osteoclasts

cells that resorb bone

osseous

bone tissue

diaphysis

shaft of the bone

• compact bone

epiphysis

expanded end of a long bone

• red bone marrow

metaphysis

between you diaphysis and distal epiphysis

• growth plate is located here

periosteum

outermost layer of compact bone

• connects to the ligament and tendon

cortical bone

• compact bone

• hard dense outer layer

• allow passage of blood vessel and nerve

osteon

• formed by group of lamellae composed of collagen fibers

• parallel to stresses on the bone (weight bearing structure)

cancellous bone

• spongy bone

• found at the end of bone

• weaker and less tough

• useful in energy absorption

trabeculae

large spaces and flat beams between spaces

axial skeleton

• 80 bones

• midline of body

axial examples

skull, hyoid bone, vertebral column, rib cage

appendicular skeleton

• 126 bones

• away from the midline

appendicular example

pectoral girdle, upper extremity, pelvic girdle, lower extremity

long bone

provide support and act as a lever

short bone

• mostly cancellous bone, thank layer of cortical bone

• important in shock absorption and transmission of forces

sesamoid bone

• special type of short bone

• bone is embedded in a tendon and joint capsule

• alter angle of insertion of muscle and diminish friction

flat bone

• 2 layers of cortical bone: cancellous and marrow

• used for protection, provide large surfaces for muscle attachment

irregular bone

• cancellous bone with thick layer of cortical bone

• support distribute loads, protect spinal cord and muscle attachment

Wolff’s Law

• bone in healthy person and animal will adapt to loads placed upon it

deposition

• respond to increased stress (increase bone density)

• osteoblast dominate

deposition example

weight bearing exercises

resorption

• respond to decrease stress

• osteoclasts dominate

resorption examples

• disuse, immobilization, microgravity

• osteopenia