OS 203 2 Biomechanics of the Muskuloskeletal System - Sheet1 Flashcards
Doc Pipo’s idol
Leonardo di se Piero da Vinci
Father of modern anatomy
andreas vesalius
wrote the universal atlas of doctors in 1543
andreas vesalius (de humanis corporis fabrica)
for a muscle to be capable of movement, it’s not enough that it attaches to a bone…
it should cross a joint and attach to another bone
prevents excessive motion of joint
collateral ligament
attachment of muscle to bone
tendon
1st class lever, ex.
force-fulcrum-load, extension of elbow, spine, hip joint
2nd class lever, ex.
fulcrum-load-force, ankle
3rd class lever, ex.
fulcrum-force-load, most lever in the body
transition between elastic and plastic deformation
yield point
amt of stress necessary to produce permanent deformation
yield strength
load of failure
ultimate strength
object fails
breaking point
plastic zone =
yield point -> breaking point
elastic zone =
0-> yield point
area under curve
energy absorbed
measure of stiffness
(Young’s Modulus of Elasticity): slope of elastic zone
bone composition
70 mineral, 5-8 water, 25 matrix
mineral component of bone
(inorganic phase) - hydroxyapatite 95, impurities (usu carbon) 5
matrix component of bone
(organic phase) - collagen/ptns 98, bone cells 2
high and low impurities effects
high -> brittle; low -> soft
time-dependent response to load and strain (2)
stress relaxation (time x stress, declines); creep phenomenon (time x deformation, increaeses)
femur anisotropy (properties depend on direction of loading); Wolff’s law
compression -> tension -> bending -> shear (Wolff’s law)
bone has highest reaction to what and lowest to what.
compression, least to shearing
what is a fracture
soft tissue injury complicated bya break in teh bone
