ANATOMY - Spinal Cord Flashcards
What are the three primary roles of the spinal cord?
- Send sensory information from the periphery to the brain
- Send motor information from the brain to the periphery
- Coordinate reflexes
What is proprioception?
Proprioception is the awareness of the position and movement of the body
What is the anatomical origin of the spinal cord?
Foramen magnum
Which region of the vertebral column does the spinal cord extend to in dogs and cats?
L6 or L7 vertebrae
Which region of the vertebral column does the spinal cord extend to in cattle and horses?
S1 or S2 vertebrae
What is a spinal cord segment?
Spinal cord segment is a section of the spinal cord which gives rise to one pair of spinal nerve roots
What are the two types of nerve roots seen at the root of every spinal nerve?
Dorsal nerve root
Ventral nerve root
What is the function of the dorsal nerve root?
Dorsal nerve root transports sensory information from the periphery to the spinal cord, making it the afferent root of the spinal nerve
What is the function of the ventral nerve root?
Ventral nerve root transports motor information from the spinal cord to the periphery, making it the efferent root of the spinal nerve
What are spinal ganglia?
Spinal ganglia are aggregations of neuronal cells bodies located just outside of the spinal cord at the level of each dorsal nerve root
What are the thirty five spinal cord segments?
8 Cervical
13 Thoracic
7 Lumbar
3 Sacral
4 Caudal
Why are there eight cervical spinal cord segments but only seven cervical vertebrae?
Cervical nerve one (C1) leaves the intervertebral foramen cranial to the C1 vertebra and cervical nerve eight (C8) leaves the intervertebral foramen caudal to the C7 vertebra
Why do the caudal spinal cord segments not align with the vertebral column?
During initial embryonic development, the spinal cord and vertebral column develops at the same rate, however, as development continues, the vertebral column grows at a much faster rate, causing displacement of the caudal end of the spinal cord in relation to the vertebral column
What is the cauda equina?
The nerve roots of the lumbar and sacral spinal nerves form a bundle at the caudal end of the spinal cord known as the cauda equina
What is the name for the terminal end of the spinal cord?
Conus medullaris
What is the filum terminale?
Fibrous cord attaching the conus meduallaris of the spinal cord to the caudal vertebrae
Which structure do spinal nerves pass through to enter the periphery?
Intervertebral foramen
What is the clinical significance of the positioning of intervertebral discs relevant to the intervertebral foramina?
Intervertebral discs are located ventral to the intervertebral foramina so intervertebral disc herniation can cause compression of the spinal nerves
How is white and grey matter arranged in the spinal cord?
White matter is on the outside and grey matter forms a horn in the centre of the spinal cord
What is the grey commissure?
Grey matter surrounding the central canal of the spinal cord
What are the three main regions of the spinal cord white matter?
Dorsal funiculus
Lateral funiculus
Ventral funiculus
Which type of axons are found within the dorsal funiculus of the white matter?
Afferent (sensory) axons
Which type of axons are found within the lateral funiculus of the white matter?
Afferent (sensory) and efferent (motor) neurones
Which type of axons are found within the ventral funiculus of the white matter?
Efferent (motor) neurones
What are the three meningeal layers?
Dura mater
Arachnoid mater
Pia mater
Where does the dura mater of the spinal cord fuse to the periosteum of the skull?
Foramen magnum
What is the epidural space?
Anatomical space between the dura mater and the periosteum of the vertebral column
What fills the epidural space?
Epidural fat
The periosteum of which two vertebrae is the dura mater fused to?
C1
C2
What is the caudal point of attachment for the dura mater?
Filum terminale
What are denticulate ligaments?
Ligamentous extensions from the pia mater, through the arachnoid mater and attaching to the dura mater to stabilise the spinal cord
What is inflammation of the meninges?
Meningitis
(T/F) Meninges also surround the nerve roots
TRUE.
Which three layers of connective tissue surround the spinal nerves?
Epineurium
Perineurium
Endoneurium
