Unit 6 The spine Flashcards
What is the vertebral column?
A series of 33 bones called vertebrae linked by intervertebral disks
What are the four main functions of the vertebral column?
Protection of the spinal cord
Support by carrying the weight above the pelvis
Axis - is the central axis of the body
Movement - posture, movement and flexibility.
What are the five different sections to the vertebral column and how many vertebrae are in each section?
Cervical - 7
Thoracic - 12
Lumbar -5
Sacrum -5 fused
Coccyx - 4 fused
What is the vertebral body?
The anterior section of a vertebrae.
Weight bearing component
Body get larger more inferiorly in order to support more weight.
What are intervertebral disks?
Found between vertebrae.
Hyaline cartilage lines the superior and inferior surfaces of vertebrae.
A fibrocartilaginous disc fills the space
What is the vertebral arch?
Forms the lateral and posterior aspect of the vertebrae from lamina posterior.
Where is the spinal cord found?
Within the vertebral canal which is the alignment of the vertebral foramen from each vertebrae.
What features are common in all vertebral arches?
Spinous processes
Transverse process
Pedicle
Lamina
Articular processes
What are some unique features of a cervical vertebrae?
Bifid (bifurcating)spinous processes except in C1 (no sp) and C7 where the processes is long
Transverse foramina acts as opening for the vertebral arteries to travel to the brain
Triangular vertebral foramen
What vertebrae allows for movement of the head?
C1 atlas
C2 - axis
What are some features unique to the thoracic vertebrae?
Has superior and inferior demi facets for rib articulation.
Transverse process has a costal processes for the rib of the same number.
Circular vertebral foramen.
What are some features unique to the lumbar vertebrae?
Very large and kidney shaped vertebral bodies.
Triangular shaped vertebral formane
Short spinous processes
Shape allows needle access to the spinal cord.
What are some features of the sacrum?
Five fused vertebrae
Inverted triangle with an inferior apex
Lateral walls are part of the sacroiliac joint
What are some features of the coccyx?
Has no vertebral arches so no vertebral canal
What is lumbarisation?
Separation of S1 from the sacrum.
A congenital abnormality
What is sacralisation?
Fusion of L5 to the sacrum.
A congenital abnormality
What are congenital abnormalities?
Present at birth or of prenatal origin.
What joints connect the vertebrae together?
Superior and inferior articular facets.
Indirectly by the intervertebral discs.
What ligaments strengthen the vertebral bodies?
What is their function?
The anterior and posterior longitudinal ligaments.
Run the full length of column
Anterior is thick and prevents hyperextension.
Posterior is weaker and prevents hyperflexion.
Support the vertebral bodies.
What ligaments support the vertebrae joining at articular surfaces?
Ligamentum flavum - between lamina
Interspinous and suraspinous - attack two spinous proceses, supra attaches tips, inter is between the main length
intertransverse ligaments - between transverse processes.
What are the brain ventricles?
Four hollow fluid filled cavitys, containg CSF found in the centre of the brain.
The lateral ventricles
The third ventricle
The fourth ventricle
What is the choroid plexus?
Specialised tissue found in the brain ventricles.
Produces CSF.
What is the function of the CSF?
Made in the ventricles, fills the subarachnoid space.
Cushions the brain, supporting its weight to protect from mechanical damage.
Provides nurtitional and immune support to the brain.
What is the journey of the CSF?
Lateral ventricles
Anterioly and inferiorly towards the midline down the interventricular foramanen
Third ventricle
Posteriorly and inferiorly through the cerebral acqueduct to the fourth ventricle.
Inferiorly for the spinal cord subarachnoid space via the foramen of magendie.
OR laterally into the subarachnoid space of the brain via foramen of lushka.
Describe the location of the third and fourth ventricle
Third is located between the left and right thalamus
Fourth is anterior to the cerebellum and posterior to the midbrain.
What are the three different meningi layers?
The dura mater
The arachnoid mater
The pia mater
Give an overview of the dura mater.
Thickest and toughest of the menigeal layers
Located directly beneath the skull.
Has infoldings called dural reflections.
What are dural reflections?
Foldings of the dura mater down into the brain
Includes the falx cerebri - between the left and right cerebral cortex
………
What are dural venous sinuses?
Found between the endosteal and meningeal layers of the dura matter, these are small cavities. They drain the venous blood of the brain
For example the superior sagittal sinus found along the falx cerebri.
Give an overview of the arachnoid matter.
Above subarachnoid space, pressure in this space holds the arachnoid mater tight against the dura mater.
Has trabeculae fibres that extend through the subarachnoid space to the pia mater.
Give an overview of the pia mater.
The innermost of the meningeal layers
Covers surface of the brain.
Contains blood vessels that are filtered through the blood brain barrier to supply the brain.
What is the blood supply of the menigeal layers?
The middle meningeal artery, is between the dura mater and the inner aspect of the skull.
Originates from maxillary artery that enters the skull through the small cranium spinosum in the middle cranium fossa.
What layers of the spinal meniges can sometimes appear as one layer?
The dura mater and the arachnoid mater, the CSF in the subarachnoid space pushes and puts pressure on the arachnoid matter forcing it outwards towards the dura mater.
What are denticulate ligaments?
Lateral extension bilaterally from the pia mater to attach the the upper meningeal layers (arachnoid and dura).
Help anchor the spinal cord in space within the vertebral canal
What is the epidural space?
Is superficial to the dura mater but deep to the vertebrae.
The site of epidural injection during childbirth, allows the anesthesia to spread around spinal nerves in the proximity.
What are the different elements protecting the CNS?
The bones (cranium and vertebrae)
Meningeal layers
CSF
Where does the spinal cord end?
Where does the dural sac end?
Why is this important clinically?
The spinal cord ends at L1/L2
The dural sac ends at roughly S2.
A needle or lumbar puncture can happen between these vertebral levels in order to sample CSF without the risk of damaging the brain or the spinal cord.
May also be called a spinal tap, often between L3 and L4.
What is the cauda equina?
Continuation of spinal nerve roots through the vertebrae in the lumbar and sacral regions after the spinal cord has ended.