EXSS 356: Chapter 4/5

The biomechanics of Human Skeleton System

Minerals of the Bones

Calcium, Phosphate and Others

Function of minerals in the bones

Stifness, compressive strength

Function of collagen

Flexibility, tensile strength

What population is collagen seen more in?

Kids

Components of the bones

minerals, collagen and water

amount of bone volume filled with pores or cavities

porosity

Bone with low porosity?

cortical bone

Bone that can withstand higher compression but less strain?

cortical bone

Bone with greater stifness?

cortical bone

bone with greater mineral content?

cortical bone

Bone with high porosity?

trabecular bone

bone that can withstand higher strain but less compression?

trabecular bone

bone that is less stiff?

trabecular bone

bone with less mineral content?

trabecular bone

strain formula

deformation/original length

larger deformation indicates ________ strain

greater

the amount of deformation divided by the original length of the structure

strain

ratio of stress to strain in a loaded material

stiffness

the more stiff something is, the _______ strain it has

less

stiffness formula

stress/strain

what bone has greater shock absorbtion?

trabecular bone

the resistance to stress depends on the _________ of force?

direction

directionally dependent

anisotropic

the bone can withstand the greastest amount of what type of force?

compression

the bone can withstand the least amount of what type of force?

shear

No matter the bone, the bone is greatest at resisting what type of force?

compression

incomplete fracture occurs when the bone bends

greenstick

greenstick fractures commonly occur in ________

children

greenstick fractures usually occur on the _____ side due to _______

convex; tension

Incomplete fracture that occurs parallel to the long axis of the bone

fissured

fissured fractures are commonly seen in _______

athletes

fracture that results in shattering of he bone

comminuted

fracture often requiring plates or screw to stabilize

comminuted

Fracture in which a small piece of the bone attached to the tendon or ligament is pulled off

avulsion

avulsion fractures commonly occur at the ____ __and__ _______

heel; elbow

Complete fracture that is perpendicular to the long axis

transverse

complete fracture that is diagonal to the long axis

oblique

complete fracture that is a result of twist or torsion

spiral

the density of bone is a function Is the ______ that acts on the bone

stress

the density of bone is a function Is the stress that acts on the bone

Wolffs law

lack of weight bearing exercise, spenidn time in the water, bed rest or space travel

causes of bone atrophy

how many minutes of exercise per week?

150

how many times should muscle strengthening exercise be completed each week?

2 times

Axial or appendicular? Skull

axial

Axial or appendicular? vertebral column

axial

Axial or appendicular? sternum

axial

Axial or appendicular? ribs

axial

Axial or appendicular? sacrum or coccyx

axial

Axial or appendicular? pelvic bones

appendicular

Axial or appendicular? scapulae

appendicular

Axial or appendicular? upper and lower extermities

appendicular

bone that width=length

short bones

carpals and tarsals

short bones

bones that cover and protect

flat bones

skull, scapula, sternum, and ribs

flat bones

bones that provide a lot of attachment sites of muscles

irregular bones

vertebrae, sacrum, coccyx, maxilla, mandible

irregular bones

humerus, tibia, femur

long bones

fibrous tissue that binds bones together

synarthroses

tibula/fibula

ulna/radial

syndesmoses

______ are located in the skull

sutures

synarthroses are ___________

immovable

ampiarthroses are __________

partially movable

bones connected by cartilage

amphiarthroses

sternocostal joints

synchondroses

vertebral joints and pubis symphysis

symphyses

joints that helping expand

ampiarthroses

freely movable joints

diarthroses

Joints that are fluid filled

diarthroses

nonaxial joint

gliding joint

facet joints of the vertebrae, inter tarsal joints, inter metacarpals

gliding joints

uniaxial joint in which one surface is convex and the other is concave

hinge joint

inter phalngeal joints and ulno humeral joints

hinge joints

uniaxial joint that rotates around one axis

pivot joints

atlantoaxial joint and proximal/distal radioulnar joints

pivot joints

the _____ rotates around the _________

radius; ulna

biaxial joint with one concave surface and one convex surface

condyloid joint

radiocarpal joint, metacarpophalangeal joint (2-5)

condyloid joint

biaxial joint in which each articular bone has both a convex and a concave surface

saddle joint

carpo metacarpal joint of the thumb

saddle joint

a triaxial, convex ball like surface and concave socket

ball and socket joint

shoulder joint, hip joint

ball and socket joints

carpometacarpal joint (1 digit)

saddle

metacarpophalangeal joint

condyloid

inerphalangeal joint

hinge

intermetacarpal joint

gliding

metacarpophalangeal (2-5)

condyloid

when articulating bones habe a larger surface, there is ________ stability

greater

when the contact surface of a joint is at the maximum

close packed position

when the contact surface it not at a maximum

loose packed position

_______ position is most stable

close packed

_______ position allows for greater risk of injury

close packed

overstretch and muscle fatigue _______ stability

reduces

other tissue contribute to the _______

stability

static flexiblity

passive ROM

dynamic flexibility

active ROM

what flexibility is a better indication of structure?

passive

smaller contact surface indicates ________ ROM flexibilty

greater

larger muscles _______ flexiblity

reduce

tight muscles _____ ROM/flexiblity

reduce