Anatomy of the back Flashcards
What type of joint is a ZYGAPOPHYSEAL JOINT?
Facet joints
sinovial, plane joints
sits between articulate processes of adjacent vertebrae
innervated by RECURRENT MENINGEAL NERVES
What type of joint is an INTERVERTEBRAL JOINT?
lies between adjacent vertebrae in vertebral column
acts as a ligament holding the vertebrae together
What type of joint is a COSTOVERTEBRAL JOINT?
connect the rib to the vertebral column
ARTICULATION: connects head of rib to bodies of thoracic spinal column
What is the coccyx formed of?
vestigial vertebrae that are fused together
most commonly contains 2-3 segments
What is Luschka’s joint?
Located at C3-C7
Type of uncovertebral joint
common point for bone spurs and degeneration
What are articular processes?
= zygapophyses
projections of vertebra that fit with adjacent vertebra
What is a lamina?
plate or layer
What is a pedicle?
a bone which connects lamina to the vertebral body
Connection is known as a ‘vertebral arch’
What is the spinal canal?
cavity which contains the spinal cord within the vertebral column
What is a spinous process?
bony projection off of the posterior vertebra
This the site of attachment for muscles and ligaments
What is a transverse foramen?
Present in cervical vertebrae
cavity through which the vertebra and artery pass
What is an uncinate process?
hook-shaped
on posterolateral borders of superior surface for C3-C7
What is a transverse process?
lateral process of vertebra
What is the vertebral body?
thick, oval segment of bone
forms the centrum
What is the centrum?
front face of vertebra
What is the primary curvature (of spine)
Thoracic and Sacral
forms during foetal development
What is the secondary curvature (of spine)?
Cervical and lumbar
develops after birth
Cervical develops as infant begins to hold up their own head
What are the main vertebral levels?
C1 atlas C2 axis C3-C6 C7 - prominent spinous process T1-T12 thoracic L1-L5 lumbar Sacrum Coccyx
What are the main distinguishing features of cervical vertebrae?
BODY: smaller
SPINOUS PROCESS: bifid = bifurcates at its distal end
TRANSVERSE PROCESS: transverse foramina through which vertebral arteries travel to brain
ARTICULAR FACETS: cup-shaped or planar
VERTEBRAL CANAL: triangular
What is different about the spinous processes of C1 and C7?
C1: no spinous processes
C7: longer spinous process and may not bifurcate
What are the main distinguishing features of thoracic vertebrae?
BODY: medium sized
SPINOUS PROCESS: orientated obliquely, inferiorly and posteriorly
TRANSVERSE PROCESS: costal facets articulates with shaft of 1st rib
ARTICULAR FACETS: demi-facets
VEREBRAL CANAL: circular
What are the main distinguishing features of lumbar vertebra?
BODY: largest and kidney shaped
SPINOUS PROCESS: shorter than that of thoracic vertebra
TRANSVERSE PROCESS: no transverse foramina
ARTICULAR FACETS: no costal facets
VERTEBRAL CANAL: triangular
What is kyphosis?
abnormal excessive CONVEX THORACIC + SACRAL curvature
What is Lordosis?
abnormal inward CONCAVE lordotic curving
What is Scoliosis?
sideways curvature of spine
Where does rotation mainly occur in the spine?
cervical
upper thoracic spine
What actions are mediated mainly by C1-2?
nodding
rotation
of head
Where does flexion and extension mainly occur in the spine?
cervical and lumbar spine
Where does lateral flexion mainly occur in the spine?
all regions
but more cervical and lumbar
What is the vertebra prominens
@ C7: prominent spinal process which can be palpated at base of neck
function: supports skull, enabling rotation and nodding movements
also protects spinal cord
What is the significance of the transverse foramina of cervical vertebrae?
occupies in C1-C6
not C7 (even though it contains spinous process)
8 cranial nerves
What is the composition of the sacrum?
5 fused vertebra
What is the median sacral crest?
fused sacral spinous processes
What is the blood supply to the venous column?
single anterior spinal artery (ASA)
ASA comes from vertebral arteries (from subclavian). It travels caudally down the spinal cord via the anterior sulcus. ASA supplies anterior 2/3 of spinal cord
2x posterior spinal arteries (PSA)
PSA is a branch o the posterior inferior cerebellar artery or pre-atlantal vertebral arteries which travel down via the (2x) posterior sulci. PSA supplies posterior 1/3 of spinal cord
What is the venous drainage of the spinal cord?
1x anterior spinal vein and 1x posterior vein
becomes internal vertebral venous plexus -> external plexus -> azygos vein -> IVC
Same drainage as lung, breast and prostate
(hence risk of mets)
What is the function of the cruciform ligament?
holds posterior ‘dens’ of C2 in articulation @ atlanto-axial joint
What is the function of the Alar ligaments?
limits the amount of rotation in the head
Also attaches the skull to the axis (C1)
Why is the Ligamentum Flava yellowish in colour? What does it connect?
high [elastin]
connects 2 adjacent vertebrae via laminae and fuses with the facet joint capsules
provides sheath covering over spinal cord
Where are the vertebral end-plates located?
this is a thin plate of cartilage
covers the lower and upper surfaces of the vertebral bodies
What proportion of the length of the spine is made up of discs?
25%
height of discs declines with age
What is the function of the nucleus pulposus?
= inner core of vertebral disc
made up of a jelly-like inner structure (elastin , loose collagen)
allows vertebral disc to withstand forces of compression and torsion
Which disc is most commonly affected in disc herniation?
95% are at either L4-5 or L5-S1
caused by disc regeneration
What is the function of the erector spinae muscle?
straighten and rotate spine
What is the function of the latissimus dorsi muscle?
extension, adduction, transverse extension, flexion
What is the function of the trapezius muscle?
tilt/tuen head, shrug, twist arms
What are the attachments of the erector spinae muscles?
medial crest of sacrum and spinous processes of lumbar, T11-12, supraspinous ligament
What is the innervation of the erector spinae muscles?
DORSAL RAMI: posterior divisions of spinal nerves
between C1-L5
At what vertebral level does the spinal cord terminate (in adult)?
L1-L2
Which vertebral level is implied if there is a delayed ankle reflex?
L5-S1
Also most common place for disk herniation and disk regeneration
