The Spine Flashcards
How many total vertebrae are there, and how many are movable?
33 total; 24 moveable
What are the segments of the spine, and how many vertebrae are in each segment?
cervical - 7 thoracic - 12 lumbar - 5 sacrum - 5 fused coccyx - 4 fused (actually between 3-5, but we say 4)
What kind of discs are intervertebral discs? i.e. what are they made of?
fibrocartilagenous discs
What’s the key function of intervertebral discs?
weight bearing (not much to do with movement)
What’s the naming convention for each disc?
named for the 2 vertebrae that it sits between
Are there discs between all vertebrae?
no disc between C1 and C2
What’s the name of the outer layer of the disc?
annulus fibrosis
Approximately how much of the total length of the vertebral column is made up of discs?
about 25%
What’s the jelly-like inner substance of the disc called?
nucleus pulposus
Does the disc have a nerve or blood supply?
- aneural except in the peripheral 1/3rd
- avascular
What are the terms that describe each section of curvature in the spine?
cervical - lordotic (lordos = curve forward)
thoracic - kyphotic (kyphos = humpback)
lumbar - lordotic
sacral - kyphotic
If there is an excessive forward curve in a section of the spine, the term would be…
- hyperlordotic for excessive forward curve
- hyperkyphotic for excessive humpback curve
Which spinal sections are termed primary and secondary and why?
- thoracic and sacral curves are termed primary because they develop during the fetal period
- cervical and lumbar are termed secondary because they don’t start until the baby lifts its head, then further when the child starts walking
What’s the aka for intervertebral joints?
zygapophysial joints
The arch of a vertebra is formed anteriorly by the:
pedicles (project posteriorly from both sides of the superior part of the vertebral body)
The area between the superior and inferior articular processes:
pars interarticularis
The aka for C1 vertebra
atlas
The aka for C2 vertebra
axis
The most common fracture site of a typical vertebra
pars interarticularis
The transverse foramen of the atlas allows for passage of the:
vertebral artery
The vertebral artery passes superiorly through the transverse foramen, then medially past the ___ before reaching the skull
groove for the vertebral artery (in the atlas)
What’s the aka for the dens?
odontoid process
On which vertebra would you find the dens?
C2 (axis)
Which vertebrae are considered upper and lower cervical spine?
upper: C1, C2
lower: C3-C7
Which vertebrae are “atypical”?
C1 and C2
What makes C1 vertebra atypical?
- no vertebral body
- no spinous process
- anterior arch
- posterior arch
- articular facet for the dens
- tubercles for transverse ligament of the atlas
- 2 lateral masses (TVPs are projections from the lateral masses)
- transverse foramen allows passage of the vertebral artery
- groove for the vertebral artery
What makes C2 vertebra atypical?
- dens (aka odontoid process)
- anterior articular facet (on the dens)
- posterior articular facet (on the dens – for the transverse ligament of the atlas)
What special features do vertebrae C2-C6 have in common?
their SPs are bifid
The aka for the SP of C7
vertebra prominens
What are the upward bony projections on the posterolateral rims of the vertebral bodies of the lower cervical spine?
uncinate processes
What are the joints at the vertebral bodies of the lower cervical spine called?
uncovertebral joints aka joints of Lushka
What do uncinate processes do?
prevent excessive glide that could damage the vertebral artery
What’s the anterior tubercle of C6 called?
carotid tubercle (carotid artery passes through here)
A horizontal line drawn between the tops of the iliac crest landmarks which SP?
SP of L4
This is the most prominent point on the anterior base of the sacrum
promontory
These are for the ventral and dorsal divisions of sacral nerves (passageway)
anterior and posterior sacral foramina
This is the continuation of the vertebral canal through the sacrum
sacral canal
This is the inferior opening of the sacred canal (nerves exit here)
sacral hiatus
The inferior processes of S5 projecting on either side of the sacral hiatus are called
sacral cornu (horn)
The fused remnants of SPs in the sacrum
median sacral crest
The fused remnants of TVPs in the sacrum
lateral sacral crest
The surfaces that join the SI joint
auricular surfaces of the sacrum and illium
What kind of joint is the lumbosacral joint?
cartilaginous
Where do the iliolumbar ligaments attach and what do they do?
- attaches to TVPs of L4 and L5 to posterior iliac crest
- key stabilizer of L5
- limits lateral flexion
What kind of joints are the sacroiliac joints and what movements are available?
- synovial plane
- limited gliding and rotational movements
Which are the ligaments that connect the ilium to the sacrum?
- anterior and posterior sacroiliac ligaments
- interosseous sacroiliac ligaments (lies just anterior/deep to the posterior SI ligs)
- sacrotuberous and sacrospinous ligs are accessory SI joint ligs)
Which superior vertebral joints don’t have IVDs?
atlanto-occipital and atlanto-axial joints
What articulates with the articular occipital condyles?
superior articular facets on the lateral masses of C1
What kind of joint is the atlanto-occipital?
synovial condyloid
What are the available movements of the atlanto-occipital joint?
-flexion and extension of head on neck
What are the ligaments of the atlanto-occipital joint?
atlanto-occipital membrane
What kind of joint is the atlanto-axial joint?
synovial pivot
What are the movements of the atlanto-axial joint?
about 70 degrees of rotation
What, specifically, articulates in the atlanto-axial joint?
the articular facet (for the dens) of C1 articulates with the dens (anterior) of C2
What are the ligaments of the atlanto-axial joint and what do they do?
- transverse ligament of the atlas (holds the dens of C2 against the anterior arch of C1)
- cruciate/cruciform ligament
- alar ligaments (prevent excessive rotation)
- apical ligament
Where is the cruciate/cruciform ligament?
band travels from transverse ligament superiorly to the occipital bone and inferiorly to the body of C2
Where are the alar ligaments?
dens to lateral margins of foramen magnum
Where’s the apical ligament?
dens to anterior margin of foramen magnum
Where’s the posterior longitudinal ligament?
located right against vertebral bodies and IVDs from sacrum to C2
Where is the tectorial membrane?
the most superior part of the posterior longitudinal ligament (C2-occiput)
Which direction would be most common for disc herniation?
posterolateral
What does the posterior longitudinal ligament (PLL) do?
- checks hyperflexion of the spine
- prevents posterior protrusion of the IVDs
What does the anterior longitudinal ligament (ALL) do?
- checks hyperextension of the spine
- stabilizes intervertebral joints
Where’s the anterior longitudinal ligament (ALL)?
travels/is anchored to the anterior aspect of vertebral bodies and IVDs from sacrum to occiput
What kind of joints are the vertebral facet joints?
synovial plane
What’s the orientation of the facet joints of the cervical, thoracic and lumbar spine, and what does their various orientation allow?
- cervical: oblique (higher anteriorly) (allows more rotation)
- thoracic: more in frontal plane (allows more lateral flexion)
- lumbar: more in sagittal plane (allows more flexion/extension)
What are the available movements of the spine?
- rotation
- flexion
- extension
- lateral flexion
Where are the ligamentum flava and what do they do?
- lamina to lamina from sacrum to C1
- help preserve normal curves
- help return spine to normal position after flexion
Where are the interspinous ligaments and what do they do?
- between SPs
- limit flexion
Where are the supraspinous ligaments and what do they do?
- posteriorly along tips of SPs from C7 to sacrum
- limits flexion
Where is the ligamentum nuchae?
- from C7 to back of skull
- thickening of interspinous/supraspinous ligaments
Where exactly does the sternoclavicular (S-C) joint attach?
- clavicle articulates with manubrium and costal cartilage of rib 1
- it’s a shock absorber for forces along clavicle
What kind of joint is the sternoclavicular?
- synovial saddle
- joint surfaces separated by a fibrocartilagenous articular disc
What are the available movements of the sternoclavicular joint?
- elevation/depression
- protraction/retraction
- rotation
What/where are the ligaments of the sternoclavicular joint?
- costoclavicular (first rib to sternal end of clavicle) (checks all movements of clavicle except inferior)
- interclavicular ligament (connects the 2 SC joints across the manubrium)
- sternoclavicular ligament (anterior and posterior)
What kind of joint is the manubriosternal joint and what movements are available?
- cartilaginous
- some movement during respiration
What kind of joint is the xiphisternal?
cartilaginous
What, exactly, articulates in the chondrosternal joints and what kind of joints are they?
- cartilages of first 7 ribs and costal notches of lateral borders of sternum
- rib 1 and manubrium: cartilagenous
- ribs 2-7 synovial (atypical, so not plane, ball and socket…)
What are the chondrosternal ligaments called?
radiate sternocostal ligaments (at articulations)
What kind of joints are costochondral and what exactly articulates?
- cartilaginous
- lateral end of each costal cartilage fits into a cup-shaped anterior end of its associated rib
There are no ligaments at the costochondral joints. What are they supported by?
supported/bound together by periosteum
What exactly articulates at the interchondral joints and what kind of joints are they?
- adjacent borders of costal cartilages articulate
- synovial (not typical)
- (supported by interchondral ligaments)
What kind of joints are the costovertebral?
synovial plane
Where do radiate ligaments of the costovertebral joints attach?
head of rib to the 2 vertebral bodies and disc in between