Trunk Flashcards
vertebrae
-classification
unfused -cervical: 7 -thoracic: 12 -lumbar: 5 fused -sacral: 5 (fused as sacrum) -coccygeal: 4 (may be 3 or 5)
What 2 types of natural curvatures occur in the spine?
primary
secondary
primary curvatures
- what are they?
- convex anterior or posterior?
- names
what -curvatures present embryologically -carried through during birth convex posteriorly -yield the curvature of the fetal position names -thoracic -sacral
secondary curvatures
- what are they?
- result of…
- types
what -curvatures that develop postnatally result of neuromuscular development necessary for -head support -bipedal locomotion types -cervical -lumbar
cervical curvature
- convex anterior or posterior
- purpose of development
convex anterior
develops to support the head
lumbar curvature
- convex anterior or posterior
- purpose of development
convex anterior
develops to support the body for bipedal locomotion
abnormal curvatures
-types
kyphosis
lordosis
scoliosis
kyphosis
- what is it?
- commonly seen in…
- due to…
- Poliomyelitis infection
what
-exaggerated posterior curvature
commonly seen in elderly with an exaggerated thoracic curvature giving the impression of a “humpback”
due to changes that occur during aging that result in
-bone loss
-loss of turgidity of the nucleus pulposus
can also be seen as a response to muscular changes following recovery from Poliomyelitis infection
lordosis
- what is it?
- commonly seen in…
what
-exaggerated anterior curvature
commonly seen in women during pregnancy
-response to shifting of weight
scoliosis
- what is it?
- result of…
what
-abnormal lateral curvature
result of…
-incomplete formation of vertebrae (hemivertebrae)
OR
-unequal muscle tension exerted on one side of the vertebral column
landmarks of a typical vertebrae (7)
body vertebral arch pedicles lamina spinous process transverse process articular processes (zygapophysis)
body
- anterior or posterior aspect of vertebra?
- how does size change throughout spinal column?
- why are the inferior and superior surfaces marked by a roughened circumference (perimeter)?
- what is the smooth center composed of and why?
anterior aspect
size
-size increases inferiorly from cervical region through lumbar region
-size decreases from lumbar region through coccygeal region
roughened perimeter is a result of the attachment of the annulus fibrosus fibrocartilage of IV disc
smooth center
-composed of hyaline cartilage
-corresponds to position of nucleus pulposus
vertebral arch
- encloses…
- what is the vertebral canal?
- arch formed by…
encloses the vertebral foramen
vertebral canal
-canal formed by all vertebral foraminae collectively
formed by
-pedicles and laminae as they join via the transverse and spinous processes
pedicles
- span what distance?
- pedicle contains which two notches?
- purpose of notches
span distance between body and transverse processes
notches
-superior and inferior vertebral notches
purpose
-from the intervertebral foramen (spinal nerve passes through)
lamina
-span what distance?
span distance between transverse process and spinous process
spinous process
-projects…
projects posterior inferiorly
transverse process
- projects…
- purpose
project posterolaterally and slightly superiorly
act as leverage for the attachment of the intrinsic muscles of the back
-specifically the intermediate and deep or transversospinalis layers of muscles
articular processes (zygopophysis)
- most commonly referred to as…
- composed of what two structures?
- joint type
most commonly referred to as facet joints
composed of paired superior and inferior articular processes with an articular facet (face)
synovial planar joint
superior articular facet face
- direction importance
- cervical direction (C3-C7)
- thoracic direction
- lumbar direction
direction importance
-used an an identifying characteristic of each level of vertebrae
*face points perpendicular to plane of articular process
-i.e. face of lumbar superior articular process points inward; plane of process is in sagittal plane
cervical direction
-posterosuperior
thoracic direction
-posterior
lumbar direction
-medial
cervical vertebrae
- unique characteristics (3)
- what is the vertebra prominens?
-larger vertebral foramen (spinal canal) - more nerves (axons) coming out of these areas
-foramen transversarium for passage of vertebral artery (may be diminished in C7)
-bifid spinous processes (C1 only has a posterior arch)
vertebra prominens
-spinous process of C7
C1 and C2 characteristics
C1 -has no body, only an anterior ventral (posterior) arch C2 -has the odontoid process (dens) --formed from body of C1
important cervical ligaments
cruciform ligament
alar ligaments
thoracic vertebrae unique characteristics -costal facets --purpose --occur where --what type of facets are they and why? spinous process direction -purpose -rotation limited due to...
costal facets
-for articulation with ribs
where
-on side of vertebral body and transverse process of superior 10 ribs
-on pedicle for articulation with ribs 10-12
type
-demi- or hemifacets since articulation of head of the rib spans the intervertebral space
spinous processes are sloped posteroinferiorly
-restrict inferiorly
rotation limited due to true ribs
-more rotation in false and floating rib regions
lumbar vertebrae special characteristics (2)
- why is L5 transverse process elongated
- spina bifida occulta results due to…
- spinous processes point…
massive bodies and lamina
no costal facets
L5 transverse process elongated for attachment of iliolumbar ligament
spina bifida occulta
-failure of closure of the posterior neuropore at L4
spinous processes point posteriorly
sacral vertebrae
- foraminae: number, purpose, and size difference
- sacral base articulates with…
- sacral hiatus
- sacral cornu
- sacral promontory
- auricular surface
- -articulates with…
- -type of joint
- -when does ossification occur?
foraminae -4 dorsal pairs and 4 ventral pairs -for exit of spinal nerves -dorsal are smaller base of sacrum articulates with body of L5 sacral hiatus -inferior opening of spinal canal -after S3 (due to lack of spinous process) sacral cornu -remnant of inferior articular process -borders sacral hiatus sacral promontory -body of S1 auricular surface -articular with ilium (SI joint) -synovial planar joint (same as facet joints) -ossifies following puberty in males; after menopause in females
coccygeal vertebrae
-remain as…
remain as bodies only
primary vertebrae ossification sites
- how many?
- what?
3
- body (centrum)
- two lateral parts of the arch (pedicles?)
secondary vertebrae ossification sites
- how many?
- what?
5
-tips of the spinous and transverse processes along the superior and inferior rims of the body (future site of attachment of annulus fibrosus)
intervertebral joints
-what type of joint?
secondary cartilaginous
similar to symphyses
ligaments of the trunk (5)
anterior longitudinal ligament posterior longitudinal ligament ligamentum flavum interspinous limgament supraspinous ligament
anterior longitudinal ligament -attached to... -functions only ligament that... -supports... -inderdigitates with...
attached to periosteum of the anterior side of body and intervertebral disc
functions
-stability of the joint
only ligament that limits extension (prevents hyperextension)
supports
-anterior and lateral aspects of vertebral body
inderdigitates with
-annulus fibrosus/fibrous capsule of disc
posterior longitudinal ligament
- attached to
- purpose
- strength and size compared to ALL
- continues into what?
- what structures does it move through and attach to inside the skull?
- where is the least supported region of the disc?
attached to
-posterior side of the body
purpose
-stability
-prevention of hyperflexion
-prevents direct posterior protrusion of the nucleus pulposus into vertebral canal
weaker, narrower, and thinner than the ALL
continues as tectorial membrane from C2 onto the inferior surface of the skull
moves through foramen magnum to the inside of the posterior cranial fossa
least supported region of is posterolateral region
ligamentum flavum
- attaches…
- color and composition
attaches lamina to lamina
yellow in color
made primarily of elastic connective tissue
interspinous ligament
-connects…
connects successive spinous processes
supraspinous ligament
- connects
- also called the ____ in the _____ regions
- in humans, it is
continuous ligament connecting successive tips of each spinous process
also called the Ligamentum Nuchae in the upper thoracic and cervical region
mostly a fascial sheath in humans (most prominent in quadrupeds who need assistance extending the head)
intervertebral disc
- composition
- remnant of…
- between which vertebrae is a disc missing?
composition
-outer ring of fibrocartilage (annulus fibrosus)
-internal part primarily composed of water (nucleus pulposus)
remnant of the embryological notochord
no discs
-occiput and atlas (C0C1)
-atlas and axis (C1C2)
last intact disc is between sacrum and L5
annulus fibrosus
- made of…
- how is the fibrocartilage oriented
- where is it thicker?
- supporeted by which ligament?
- where is it thinner and less supported?
made of concentric rings of fibrocartilage
each layer of fibrocartilage is oriented about 90 degrees differently for strength
thicker on the anterior side
supported more heavily by the anterior longitudinal ligament
thinner and less supporeted posteriorly
more logical direction of herniation of the internalized nucleus pulposus