Anatomy of spinal chord and spinal nerves Flashcards
What does the spinal chord exit the brain via
The foramen magnum
What segment does the spinal chord terminate at
L1/L2
What are the segments of the spinal chord
Cervical - 8 Pairs
Thoracic - 12 Pairs
Lumbar - 5 Pairs
Saccral - 5 Pairs
Coccygeal - 1 Pair
What is special about the cervical segment
- It is the only segment that nerves move above its corresponding vertebrate (apart from C8)
- The other segments move beneath their corresponding vertebrate
What are the cauda equina and where are they located
- Bundle of spinal nerves coming off the spinal cord
- L2-CO1
Where is the cervical enlargement located?
Why is it enlarged?
- C5-T1
- Contains more grey matter within the ventral horns of the spinal cord - associated with upper limb muscles
Where is the Lumbar enlargement located
Why is it enlarged?
- L2-S3
- A lot more grey matter in the ventral grey horn - associated with skeletal muscles of the lower limbs
What is the white matter
- Carries ascending information up and descending information down
- As we go up to the cervical segment, it gets fatter as there’s more nerve fibres
Which way does the grey matter increase?
What does the grey matter supply?
Grey matter increases in size as we go down, it supplies the bigger and fatter muscles with motor supply from the ventral grey horn
What are the main sections of neurones?
Which parts of the neurone are white matter and grey matter
2 sections - Cell bodies + myelin sheaths
White matter: Myelinated axons
Grey matter: Cell bodies
What does the grey matter and white matter make
Grey matter - makes the horns
White matter - makes the column
Complete this image
Where is the lateral grey horn present between?
What does it consist of?
- T1-L2
- Consists of the pre-ganglionic motor neurone of the sympathetic nervous system
What is the dorsal grey horn associated with
Sensory neurones
What are sensory neurones associated with
Associated with dorsal grey horn synapses
What does the ventral grey horn contain
Contains motor neurone-cell bodies
What does the dorsal white column contain
Ascending tracts (sensory info up to the brain)
What does the lateral white column contain
Descending motor tracts
What does the ventral white column contain
Ascending and descending tracts - motor + sensory info
In the CNS, what is a nucleus and what is a tract
Nucleus - A bundle of cell bodies
Tract - A bundle of axons
Label the features of the spinal roots
What is the function of the dorsal root
Transmit sensory information from the body to the central nervous system (CNS)
