Control L10 spinal cord and spinal nerves Flashcards
How many cervical vertebrae are there?
7
How many thoracic vertebrae are there?
12
How many lumbar vertebrae are there?
5
How many vertebrae are there in the sacrum?
5 - fused
How many vertebrae are in the coccyx?
3-4 - fused
What is the role of the vertebral column?
Contains and protects the spinal cord and beginning of spinal nerves
What part of the brain is the spinal cord continuous with?
The medulla oblongata
At what vertebral level does the spinal cord terminate?
LI-L2
What does the spinal cord terminate as?
Conus medillaris leading into the cauda equina and filum terminale
What foramina of the brain does the spinal cord pass through?
Foramen magnum
How many spinal nerves segments/pairs are there?
31 = 8 cervical, 12 thoracic, 5 lumbar, 5 sacral + 1 coccygeal
At what vertebral level is the lumbar cistern?
Below LI/L2
What nerves are involved in the lumbrosacral enlargement?
The lumbrosacral plexus = L1-S4
What nerves are involved in the cervical enlargement?
The brachial plexus = C4-T1 (C4 not in brachial plexus)
What nerves make up the cauda equina?
Dorsal and ventral roots of lower lumbar, sacral and coccygeal spinal nerves.
Where do the spinal nerves leave the spinal cord in relation to the equivalent vertebrae?
C1-C7 leave above corresponding vertebrae (I.e C1 nerve leaves above C1 vertebrae)
C8 leaves above vertebrae T1
T1-Coccygeal nerve leave below corresponding vertebrae (i.e. T3 leaves below T3 vertebrae)
What is the epineurium?
a protective outer sheath of connective tissue which surround each spinal nerve as they leave the vertebral canal (part of the meningeal coverings of the spinal cord)
What ligaments are found in the subarachnoid space of the spinal cord?
Denticulate ligaments
How does the spinal dura differ from the cranial dura?
Only has one layer of dura mater - the meningeal layer - in the spinal cord (compared to 2 surrounding the brain)
Spine has real epidural space where as only potential epidural space in the cranial cavity.
The periosteum layer forms the part of the dura mater around the brain but only surround the vertebrae in enrage column - not the spinal cord.
Why is there disparity between where the spinal roots emerge from the spinal cord and where they emerge between the vertebrae?
As during the development the ducal sac grows with along the vertebrae not the spinal cord.
Why is the cauda equina not usually damage by lumbar puncture?
As the nerve roots can move out of the way when the needle is inserted
At what vertebral level is epidural anaesthesia usually administered?
Between L2 and L3 or at the sacral hiatus
At what vertebral level is a lumbar puncture usually taken?
Between vertebrae L3 and L4 or L4 and L5
What is the role of ligamentum flavour?
To connect the lamina of adjacent vertebrae
What arteries run in the posterior lateral sulci of the spinal cord?
The posterior spinal arteries
What artery runs in the anterior median fissure of the spinal cord?
Anterior spinal artery
What artery supplying the spinal cord arises from the aorta?
The segmental spinal arteries
What arteries supplying the spinal cord arise from the segmental arteries?
The medullary artery
The anterior and posterior radicular arteries
What arteries supply the spinal cord?
Anterior spinal artery
Posterior spinal arteries
Medullary arteries
Segmental arteries
Anterior and posterior radicular arteries
How many spinal nerves arise from each spinal level?
2 = 1pair
How do spinal nerves emerge from the spinal cord?
Ventral rootlets arise from the anterior lateral sulcus and form the ventral root
Dorsal rootlets arise from the posterior lateral sulcus and form the dorsal root and ganglion
The ventral root and dorsal root converge to form the segmental spinal nerve
What fibres travel through the dorsal root and ganglion?
Afferent somatic and visceral sensory fibres
What fibres travel in the ventral root?
Efferent somatic and visceral motor fibres
In what spinal segments of the spinal cord is there a lateral grey horn?
T1-L2 and S2-S4
How does the amount of white matter change as you ascend in the cord?
White matter increases as you ascend the cord
Where are the ventral grey horns in the spinal cord enlarged?
Where motor fibres to limbs arise I.e. at the cervical and lumbrosacral enlargements
At what point does the cuneate fascicles appear?
At T6 and above
What regions is grey matter in the spinal cord divided into?
Rexed’s laminae
