SpinalBioMech. Spinal Column Flashcards
start at spinal column (2) pg 4
L/S is subjected to ____ due to the lordortic curve
anterior shear force
L/S anterior shear forces are due to ______
lordotic curve
The anterior shear force is resisted by the ___ & ____
facet joints & deep erector spinae M.
lumbosacral angle is ____ degrees
30 degrees
*** structure and fxn of the SI joint changes significantly w/ ___&____
growth and development
Who stays more flexible over life ? man vs female?
Female
also have hormone relaxin during preg
____: withstands the compressive loads of the upper body in static & dynasmic situations
kinetics
muscle compression increased _ ____loads
compressive loads
compressive loads (decrease/increase) during walking
increase
Motion of the SI jt is linked to motion at the _____
pubic symphysis
the pubic symphysis is a ___ kinematic chain
closed
smooth joint surfaces in SI jts allow ____motion in all ranges
gliding
the SI joint _____ as we age
fuses
- develop furrows and grooves within the joint
joint surfaces change after ____ & only allow slight translation / rotation
puberty
___: sacral promontory (base) moves anterior & inferior while the coccyx moves posterior
nutation
sacral nutation is the sacral promontory (base) moves ____ & ___ while the coccyx moved _____
base: anterior & inferior
Coccyx: posterior
___ : sacral promontory moved posterior & superior while the coccyx moves anterior
sacral counter nutation
sacral counter nutation : sacral promontory moves _ & ___ while he coccyx moves ____
Base: posterior & superior
coccyx: anterior
____ theory: (classic) axis of tilt at the interosseous lig. , just posterior to the joint
Farabeuf’s theory
Farabeuf’s theory: axis of tilt is at the _____
interosseous lig, just posterior to the joint
______ theory: axis of tilt is at ____ tubercle, near the center of the joint
bonnaire’s theory
bonnaires tubercle
__ theory: says no axis of tilt, pure translation
Weissels theory (1)
__ theory: axis is in the pelvic bowl & varies from person to person
weissels theory (2)
______ is extremely important for the SI joint support
stability
_ loads of BW causes a nutation torque on the sacrum
compressive
compressive loads of BW cause a nutation __ on the sacrum
torque
ground reaction forces cause _ tilt forces on the ilia
posterior
forces are resisted by ____ systems
ligament
joint irregularities (suc as depressions/ridges) develop with age to help wth _____
stability
- by limiting motion
___ structure resists shear forces during gait
pubic symphysis
