Vertebral column: vertebral canal Flashcards
ligaments of the vertebral column can be divided into what groups
ligaments of the body ligaments of the arch and processes
what are the 2 subdivisions of ligaments of the vertebral body
anterior longitudinal ligament
posterior longitudinal ligament
where does the anterior longitudinal ligament run
anterolateral aspect of the vertebral bodies from the skull base to the sacrum
describe the structure of the anterior longitudinal ligament
3 layer of dense collagen fibres
what do the deep fibres of the anterior longitudinal ligament do
bind adjacent vertebrae together
what do the superficial fibres of anterior longitudinal ligament do
span multiple segments
what is the function of anterior longitudinal ligament
limits extension
how does anterior longitudinal ligament limit extension
only ligament that lies anterior to axis of movement
where does the posterior longitudinal ligament run
within the vertebral canal on the posterior aspects of the vertebral bodies from C2 to sacrum
the posterior longitudinal ligament is much _____ than the anterior
narrower
the posterior longitudinal ligament attaches mainly to what
IVDs and margins of the vertebral bodies
what is found between ligament and bony surfaces of vertebral bodies
fat and vessels
what is the function of posterior longitudinal ligament
weakly limits flexion (posterior to axis of movement)
but mainly prevents herniation of IVD by reinforcing them
what are the 5 divisions of the ligaments of the vertebral arch and processes
ligamenta flava
interspinous ligaments
supraspinous ligaments
intertransverse ligaments
nuchal ligaments
where does a single ligamentum flavum run
connects laminae of adjacent vertebrae
ligamentum flava are made of
strong elastic fibres
ligamentum flava limit
flexion
what are 3 functions of the ligamentum flava
- help maintain curvatures
- reinforce and close off gaps in wall of vertebral canal posteriorly
- limit flexion
interspinous ligaments connect
adjacent spinous processes
are interspinous ligaments strong
no - weak, thin, membranous
supraspinous ligaments connect
tips of spinous processes
are supraspinous ligaments strong
yes, cord like
supraspinous ligaments are found where
C7 –> sacrum
intertransverse ligaments connect
adjacent transverse processes
how do the intertransverse ligaments differ as you go along the spinal cord
cervical - scattered fibres
thoracic - fibrous
lumbar - membranous
what replaces the supraspinous ligaments superiorly
above C7 there is the nuchal ligament
the interspinous and supraspinous ligaments limit
flexion
the nuchal ligament is continuous with
supraspinous ligament
the nuchal ligament limits
flexion
describe the nuchal ligament
thickened fibroelastic tissue
where does the nuchal ligament attach
external occipital protuberance
posterior border foramen magnum
spinous processes C1-7
what is the function of nuchal ligament
muscle attachment
where does the spinal cord extend between
foramen magnum and L1/2
where does the spinal cord end
L1/2
what happens at the end of the spinal cord
end narrows forming the medullary cone
where are the 2 enlargements of the spinal cord
cervical enlargement and lumbosacral enlargement
what level is the cervical enlargement
C4-T1
what level is the lumbosacral enlargement
L1-S3
how are the cervical spinal nerves named
cervical spinal nerves are named after the vertebra below except for C8 - emerges below C7 and above T1 as no C8 vertebrae
C5 spinal nerve will emerge
between C4/5
how are spinal nerves of T1-Co1 named
named after vertebrae above
T5 spinal nerve will emerge
between T5/6
how is the cauda equina formed
a number of spinal nerves have a long way to travel from the end of the spinal cord in order to reach exit point - results in a collection of spinal nerves that run below the end of spinal cord (lumbar and sacral roots)
what is the name for the remnant of the caudal part of the spinal cord
filum terminale
where is the filum terminale found
in amongst cauda equina
what comprises the filum terminale
small amount of nervous tissue, but also some coverings of spinal cord. particularly pia mater
where does the filum terminale run
extends from tip of conus medullaris and runs down to attach on coccyx
why is the spinal cord shorter than the verterbal column
differential growth rate between the 2 structures - the VC grows more rapidly relative to the cord
at what age are the cord and column the same length
3 months gestation
at 5 months gestation what can be seen
there has been much more rapid growth of the column relative to the cord and as a result the area of the spinal cord that gives rise to a spinal nerve is no longer at the level of this vertebrae - to compensate, the root of this nerve has had to lengthen so it can reach exit point
where does the spinal cord end in the newbord
L3
what are the 3 layers of the meninges
dura mater
arachnoid mater
pia mater
are the spinal meninges continuous with the coverings of the brain
yes
the spinal meninges also extend where
along initial portions of spinal nerve roots
what are the lateral extensions of dura mater around the initial portions of the spinal nerves called
dural root sheath
to what does the spinal dua mater attach inferiorly
attaches to coccyx by filum terminale
where is the epidural space
potential space between dura mater and bone of VC
what is contained in epidural space
internal vertebral venous plexuses
epidural fat and blood vessels
describe the spinal arachnoid mater
delicate membrane with a spider web appearance that lines the dura
how is the arachnoid mater connected to the pia
arachnoid trabeculae
where is the subarachnoid space
between arachnoid and pia
what happens to the SAS as you move caudally
it enlarges into a space called the lumbar cistern that surrounds the conus medullaris
where is the lumbar cistern
L2-S2
what procedure makes use of the lumbar cistern
lumbar puncture
what is the denticulate ligament
extensions form from lateral sides of pia mater - tooth shaped/serrated ligament that extends the length of the cord
where is the denticulate ligament found
in between anterior and posterior roots of spinal nerves
how does the denticulate ligament help suspend the spinal cord within the dural sac
it pierces the arachnoid mater and anchors to the dura
what does the spinal pia mater cover
spinal cord, nerve roots and spinal blood vessels
how many longitudinal arteries supply the spinal cord
3 - 1 anterior and 2 posterior spinal arteries
where do the anterior and posterior spinal arteries run
longitudinally from medulla oblongata to conus medullaris
the longitudinal spinal arteries are supported by what
medullary segmental arteries
where do the medullary segmental arteries come from
segmental branches in the trunk e.g. intercostal arteries, lumbar arteries
how do the medullary segmental arteries support the longitudinal arteries
come in and anastomose with longitudinal vessels providing a localised blood supply to spinal cord
what arteries supply nerve roots
radicular arteries
describe the venous drainage of the spinal cord
3 anterior and 3 posterior longitudinal spinal veins and medullary and radicular veins which join the internal vertebral venous plexuses in epidural space
the veins draining the spinal cord anastomose extensively with
internal vertebral venous plexus in the epidural space
where is internal vertebral venous plexus
epidural space
the internal vertebral venous plexus receives blood from what
vertebral bodies and also spinal cord
the internal vertebral venous plexus anastomoses with what
anterior external vertebral venous plexus on anterior surface of bodies of vertebrae and with posterior external vertebral venous plexus
