Axial Skeleton Flashcards
3 bones of skull related to craniocervical region
temporal bones, occipital bone
arthrokin of AO joint
convex occiput
concave atlas
primary WB component of vertebrae
body
what part of the ribs articulates w TPs of thoracic vert?
articular tubercle
what does the anterior end of the ribs articulate with?
sternum
sternum is _______ anteriorly for organ space
convex
LOG falls to the _______ of each curve at apex
concave
role of lig flavum
resist flexion
role of supra/interspinous ligs
limit flexion
role of intertransverse ligs
resist contralateral flexion
role of lig nuchae
adds support to head
role of ALL
limits extension
role of PLL
reinforces intervertebral discs
role of capsular ligs
limits all motion except extension - can resist up to 10k N of force
where are capsular ligs found?
around each apophyseal jt
cervical region is _______ and most _______
smallest and most mobile
unique structure found in CS
transverse foramina
purpose of transverse foramina
vertebral artery ascends through these foramina
which CS are typical/atypical?
C1-2 atypical
C3-6 typical
CS _______ in size from sup–> inf direction
increase
describe transitional areas of the spine
vert start looking like segment below them
SPs of CS are _____
bifidous
primary function of atlas
support head
movements allowed at atlas
nodding
movement at axis
rotation bc dens
AAJ provides how much of the total CS rotation?
50%
typical CS vertebrae do not have SP, instead, they have…
anterior and posterior tubercles
which CS vert has an SP?
C7
stacking of sup/inf articular facets forms..
articular pillar
apophyseal joint line is _______ in CS
horizontal BC we need rotation ROM
which TS are typical and why?
T2-9
all articulate with two ribs
in TS, pedicles are _______ directed
posteriorly
vertebral canal _______ from sup–>inf direction
narrows
SPs in TS slant in what direction?
downward
apophoseal joint line is _____ in TS
nearly vertical
superior facets = posterior
inferior facets = anterior
TPs in TS project…
posterior-laterally
why is T1 atypical?
large SP and full costal facet
why are T10-12 considered atypical?
full costal facets
direction of SPs in LS
horizontally
direction of TPs in LS
laterally
apophyseal joint line in LS
vertical
function of sacrum
transmit weight of vertebral column to pelvis
name the 4 joints of the sacrum
- lumbosacral
- sacroiliac x2
- sacrococcygeal
orientation of base/apex of sacrum
base = faces superiorly apex = faces inferiorly
function of SP and TP
increase mechanical leverage of muscles/ligs
2 intervertebral joints
apophyseal joints
interbody joints
R rotation =
anterior surface of vertebrae is moving in R direction
talking about top vert moving on bottom vert
vertebral facets block these two movements
anterior translation and axial rotation
how many pairs of apophyseal joints are there?
24
horizontal facets favor ________
axial rotation
how to IV discs protect apophyseal joints?
minimizing compressive loads
lowest pressure body position for IV discs
supine
highest pressure body position for IV discs
lifting something with knees extended and hips flexed
how many DOF at AO joint?
2
primarily flex/ext and slight lateral flexion
how many DOF at AA joint?
2
rotation and flexion/extension
angle of facets from C2-7 - what is unique about this?
45º
allows 3 DOF
arthrokinematics of vert extension/flexion
extension: facets glide posteriorly/inferiorly
flexion: facets glide anteriorly/superiorly
which has more motion: protraction or retraction?
protraction
protraction _____ mid/lower CS and ______ upper CS
flexes; extends
arthrokinematics of axial rotation
same side glides posterior; opposite side glides anterior
arthrokinematics of intracervical lateral flexion
inferior/posterior glide on side of closing facet
arthrokinematics of AO joint lateral flexion
cranium rolls/slides in opposite directions
arthrokinematics of AO joint flexion/extension
roll and glide in opposite directions
describe the effect of flexion/extension on migration of nucleus pulposus
flexion = posterior migration extension = anterior migration
describe cervical spine coupling
mechanical coupling between ipsilateral lateral flexion and rotation
what is the main reason for limited movement in the TS?
ribs
why does LS have more flex/ext than rotation?
facet orientation close to saggital plane
full lumbar _____ increases diameter of foramen by 19%
flexion
intervention to reduce spinal n root pressure due to narrowing of foramen
LS flexion
prolonged LS flexion increases….
compressive force on disc, deforming gel posteriorly = HNP
full lumbar flexion ___________ within disc
reduces pressure
prolonged LS ext increases…
contact pressure btw articular facets
normal forward fold LS flexion/hip flexion ROM values
LS 40º
hip 70º
occur simultaneously
extension of trunk w knees extended is initiated by __________ followed by _________
ext of hips
ext of spine
reduces load on lumbar spine and extensor muscles by waiting until moment arm of gravity decreases
what muscles contribute to ant pelvic tilt/LS lordosis?
hip flexors and back extensors
what muscles contribute to post pelvic tilt/LS neutral?
hip extensors and abdominals
SI joint designed for _____
stability
believed to be a source of pain in 15-30% of people with LBP
SI joint dysfunction
nutation
anterior sacral tilt + posterior iliac tilt
counternutation
posterior sacral tilt + anterior iliac tilt
nutation torque increases…
stability at SI
why is nutation torque more stable?
BW transmitted through L5, anterior to 1st sacral vert, GRF creates post rotation of ilium
BW causes _____ rotation of sacrum
anterior
hip joint compression causes _____ rotation of ilium
posterior
lack of intrinsic muscle control leads to…
vulnerable vertebral column
intrinsic muscles stabilize spine by controlling ______ and _______ at intervertebral junctions
alignment and stiffness
SCM can _____ at upper CS and _____ at lower CS
extend; flex
full axial rotation gives near _________ of visual scanning
180º
TA is an ______ muscle
anticipatory
lumbopelvic instability is associated with ____
DDD
4 interventions for lumbopelvic instability
- deep stabilizer activation
- challenge wide variety of trunk muscles
- muscle endurance
- challenge postural control/proprioception
arthrokinematics of lumbar/thoracic lateral flexion
just superior and inferior movement - no AP movement like in cervical
