The vertebral column Flashcards
what makes up the axial skeleton
aka vertebral column or spine, made up of 32-33 vertebrae, ezch interacting with neighbours forming spinal units, each individual vertebrae is different
regions of the spine
Cervical- C1-7, Thoracic- T1-12, lumbar- L1-5, Sacral- S1-5, coccyx- 4 fused vertebra
spinal curves- cervical curve and lumbar curve
anterior convexity, posterior concavity, lordosis
spinal curves- thoracic and sacral curve
anterior concavity, posterior convexity, Kyphosis
normal posture- line of gravity
through mastoid process of skull, through the ear lobe, through upper cervical vertebra, through the shoulder joint, through midway trunk, through lower lumbar vertebra, posterior to hip joint, through the greater trochanter, anterior to knee and ankle joint (calcaneocuboid joint)
functions of spine- thoracic cage
supports thoracic cage- including ribs, need stable base to move and change intrathoracic dimension (draw air and force air out)
functions of spine- muscle and limb attachment
muscle attachment (irregular bones) particularly pelvic and pectoral girdle and spinal muscles upper/ lower limb attachment
functions of spine- protection
spinal cord runs through spinal foramen- larger in cervical region as it is at its largest (large canal)
functions of spine- shock
shock absorption- vertebral bodies/ muscle/ curves- allows degree of absorption in normal day to day activity, intervertebral discs
functions of spine- movement and stability
production and control of movement, give proximal stability to allow distal function
typical vertebra- 7 processes
articular process (X4), transverse process (X2), spinous process (X1)
7 processes- articular process
2 X superior and 2 X inferior, each has articular facet (synovial plane), cervical spine- rotation
7 processes- transverse process
project laterally- from junction of pedicles and laminae
function- levers for muscles and ligaments (side flex or rotate)
7 processes- spinous process
projects dorsally (often inferiorly)- insertion of muscles, for ligaments to control/ limit spinal movement vary in size, shape and direction function- levers for muscles which extend the spine
what attaches vertebra processes to vertebral body
these are attached to vertebral body by vertebral arch
typical vertebra- pedicle
joining the neural, vertebral arch to vertebral body (2 of them), expand to form superior and inferior articular processes
typical vertebra- laminar
on posterior vertebral arch- forms posterior faced spinous processes
what do vertebral bodies articulate at
they articulate at intervertebral joints
vertebral stacked- intervertebral foramen
between 2 vertebra joining, for exit spinal nerves
what do articulate processes articulate at
superior and inferior articular processes form facet/ zygapophyseal joints
vertebral stacked- lower down spine
as you descend down spine- become more robust
gradual changes as you descend down vertebra- cervical slowly changes to thoracic, which slowly changes to lumbar
what is the key difference between each spinal region
key difference is orientation of articular facet- facilitates some movement but limits other
cervical- horizontal
thoracic spine- become more vertical- facilitating rotation
lumbar spine- wrapped vertebra- face each other, orientation is vertical and facing inwards
cervical vertebra- shape and function
small retinacular body, carry weight head and muscles of neck, large vertebral foramen- lots of spinal cord (gives of fewest material- at its largest), has foramen transversum tip– hole in transverse process
cervical vertebra- processes
transverse processes are anteriorly placed, have anterior and posterior tubercles
bifid spinous process
cervical vertebra- uncovertebral joints
joints of von lushka, important as they can suffer from degenerative arthritis, where there is liping of the lateral aspect of one vertebral body articulating with its neighbour above (encloses intervertebral discs)
has synovial joint on either side
curves in cervical spine
anterior convexity- support skull C1- atlas C2 (Axis) /7 (atypical) C2- prominent spinous process C7- vertebra prominens C6- Withdraws on cervical extension
thoracic vertebra- shape
round body, long slanted spinous process, transverse process with facet- long and slender,
thoracic vertebra- joints
costal facet joints (4X), rib cage joints (2X)- demifacets on posterior aspect of body of vertebra- synovial plane joints with articulations with head of ribs (superior and inferior)- these are costorib transverse articulations
thoracic vertebra- articular facets
they are more in a vertical plane
thoracic vertebra- thoracic spine
anterior concavity, attaches the ribs, spinous process T3- spine of scapula, level with inferior angle of scapula-if patient lying in prone with arms by side
spinous process T7- level with inferior angle of scapula-if patient lying in prone
lumbar vertebra- shape
large wide body, broad short laminae and pedicles, quadrangular spinous process , transverse process thun and long- muscle attachments
lumbar vertebra- articulation
mamillary process- attachment for muscles, associated with internal aspect of superior articular facets, vertical facets, no costal facets or transverse foramina
sacrum
5 fused vertebrae, based articulation with 5th lumbar vertebra, sacral promontory and superior articular process, apex, sacral canal and foramina, concave anteriorly, spinous tubercles
when does the spinal cord cease
spinal cord ceases at L2 at the conus medullaris anything beyond this is cauda equina- less neuro material in lumbar spine
the coccyx
small triangular, 3-4 vertebra fused, directed inferior and ventrally, decrease in size
palpitation landmarks
C2- Prominent spinous process, C6- disappears on cervical extension, C7- vertebra prominens, T3- spine of scapula, T7- level with inferior angle of scapula, L4- iliac crest, S2- level of PSIS
important function of spine
important as central axis, enclosing the spinal cord, weight transfer and muscle attachment
what is vertebral unit
2 vertebra together
what is the movement of disics controlled by
it is controlled by posterior zygapophyseal joints
joints
intervertebral- vertebral bodies articulate at intervertebral joints- fibrous joints
zygapophyseal joints- superior and inferior articular processes form facet/ zygapophyseal joints- synovial plane
intervertebral joints
a symphysis (secondary cartilaginous), vertebral end plate- consist of hyaline cartilage, intervertebral discis,
shape of intervertebral joints
sandwich- vertebra- hyaline- intervertebral disc- hyaline end plate- back vto vertebra
intervertebral joints- fibrocartilaginous disc
2 parts- annulus fibrosus (rounded fibrous tissue, has more structure) and nucleus pulposus (centre pulpy- higher fluid content)
intervertebral discs- annulus fibrosus
ring of fibres, composed of 60-70% of water, layers of collagen fibres arranged in sheets called lamellae- allows strong structure and movement, run at 90° , thicker towards centre of disc and in anterior and lateral portions, thinner posteriorly, stiff structures resist buckling, within this is nucleus pulposus
intervertebral discs- nucleus pulposus
semi- fluid mass of mucoid material, 88% water, deformed under pressure from any direction, transmit the applied pressure in all directions, gives shock absorbance capacity
what does the discs do?
shock absorption, allows movement and load transition, hydro elastic properties- due to water content, stability to the spinal column, limit excessive movements, movements affected position of zygapophyseal joints and fluid of nucleus propulsus
prolapsed intervertebral disc
where nucleus pulposus fluid finds its way through the shearing damage within the annulus fibrosis (common on posterolateral aspect)
fluid puts pressure on aspect of spinal cord/ nerve
could go up or down a level to affect superior or inferior spinal nerves
zygapophyseal joint
synovial joints between. vertebral arches. inferior articular process of one vertebra with the superior articular process of the vertebra below, articular cartilage, synovial membrane, capable of degeneration
zygapophyseal joint- planes of joint
planes of the joints are different in cervical (superior facet horizontal- flex, ext, rotation), and lumbar (superior facet inwards- flex and ext), thoracic region (superior facet backwards- meet to rotation), inferior facet does opposite
ligaments supporting spine- anterior longitudinal ligament
bonded to anterior surface of vertebra bodies from C2 to sacrum and intervertebral discs, limits extension of spine
ligaments supporting spine- posterior longitudinal ligament
within spinal canal, bounded to posterior aspect of vertebra bodies and intervening vertebral discs travels from C2 to sacrum, limits spinal flexion
ligaments supporting spine- ligamentum flavum
between laminae of each adjacent vertebra, from cervical spine to lumbar spine, limits spinal flexion and rotation
ligaments supporting spine- ligament nuchae
cervical region, centre of external occipital protuberance fans out laterally on superior nuchleal line, and all the way down inferior aspect of the occiput to C1, and attaches to spinous process of C2-C7, continuous as supraspinous ligament
ligaments supporting spine- supraspinous ligament
limits flexion, ribbon like blending to tips of each spinous process down into sacrum
ligaments supporting spine- interspinous ligament
between each spinous process, limit flexion of spine
ligaments supporting spine- intertransverse ligament
between transverse process, limits side flexion to opposite side
movements of spine
flexion and extension, lateral/ side flexion, rotation, protraction and retraction of cervical spine, movements facilitated and limits by orientation of articular facets