spinal cord anatomy Flashcards
(23 cards)
What is the spinal cord?
A part of the central nervous system located inside the vertebral canal
Where does the spinal cord start and end?
From the foramen magnum to L1–L2, ending as the conus medullaris.
What is the cauda equina?
A bundle of spinal nerve roots extending from the conus medullaris.
How many pairs of spinal nerves are there?
31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal.
What are the spinal enlargements?
Cervical enlargement: supplies upper limbs
Lumbar enlargement: supplies lower limbs
Name the three meninges of the spinal cord.
Dura mater – outer tough layer
Arachnoid mater – web-like middle layer
Pia mater – inner vascular layer
What are denticulate ligaments and filum terminale?
Pia mater structures that anchor the spinal cord.
What are the meningeal spaces (deep to superficial)?
Subarachnoid space – contains CSF
Subdural space – potential space
Epidural space – fat & venous plexus
What is grey matter made of?
Neuron cell bodies, dendrites, and unmyelinated axons.
What is white matter made of?
Myelinated nerve fibers – for signal transmission.
What are the three white matter columns (funiculi)?
Anterior, Lateral, and Posterior funiculi.
What do ascending tracts do?
Transmit sensory info from the body to the brain.
What does the dorsal column-medial lemniscal pathway carry?
Fine touch, vibration, proprioception.
What does the lateral spinothalamic tract carry?
Pain and temperature.
What does the anterior spinothalamic tract carry?
Crude touch and pressure.
What is the role of spinocerebellar tracts?
Carry unconscious proprioception for motor coordination.
What do descending tracts do?
Carry motor signals from the brain to the body.
What are the two major types of motor tracts?
Pyramidal and Extrapyramidal tracts.
What is the function of pyramidal tracts?
Voluntary control of body and face muscles.
What are the pyramidal tracts?
Corticospinal tract: body muscles
Corticobulbar tract: head/neck muscles
What is the function of extrapyramidal tracts?
Involuntary control of posture, tone, balance, and reflexes.
Name extrapyramidal tracts.
Vestibulospinal
Reticulospinal
Rubrospinal
Tectospinal
What are the main arteries supplying the spinal cord?
anterior spinal artery (ASA)
posterior spinal arteries (PSA)
