Spinal cord function and dysfunction Flashcards
How many pairs of Spinal nerves are there?
31:
- 8 Cervical
- 12 Thoracic
- 5 Lumbar
- 5 Sacral
- 1 Coccygeal
Where do nerves leave the vertebral column?
Intervertebral foramina
Where are the enlargements in the cord for limb nerves?
Why?
Cervical (C3-T1) - More motor neurones that go to the muscles of the upper limb
Lumbar (L1-S3) - More motor neurones that go to the muscles of the lower limb
Where do the Cervical nerves leave the spinal column?
C1-C7 above the vertebrae
C8 Below C7 vertebrae
(All others below)
At what level of the Vertebral column does Co1 originate?
What is this an example of?
Coccygeal
Around L1
Discrepancy between spinal and vertebral levels
What is the difference between the location of the Dura in the brain and spinal cord?
What does this allow?
There is no space between dura and cranium
There is a space between dura and spinal column
This allows the injection of anaesthetics into the epidural space
Where does the Pia mater end in the vertebral column?
At the end of the spinal cord, leaving only a filament that tethers it to the sacrum.
What tethers the spinal cord and holds it in the middle of the subarachnoid space?
Denticulate Ligaments
What is a Dermatome?
An area of skin innovated by one pair of spinal nerves
What is a myotome?
Muscles innovated by one pair of spinal nerves
What type of fibres are contained in the anterior root?
Motor fibres
What type of fibres are contained in the posterior roots?
Sensory fibres
What is a ramus?
A branch of the spinal nerve that contains both motor and sensory fibres
What is a root, and what is it formed from?
A section of the spinal nerve formed of only one type of fibre, formed from rootlets
Label the sections of this transverse plane of the Spinal Cord
Label the Major Tracts of the White Matter
What proportion of motor fibres cross over and innovate limbs?
About 85%
How many neurones are involved in Sensory Pathways?
3
Primary sensory neurone enters cord and synapses onto secondary
Secondary crosses over - either in cord or medulla
Secondary synapses with tertiary in the Thalamus
Tertiary travels to cortex
What does the Dorsal column pathway carry?
Whats it made of?
Discriminative touch, Vibration and Proprioception sensory infomation
Fasciculus Gracilis and Fasciculus Cuneatus
Where does the Dorsal Column Pathway cross over?
Medulla
What information does the Spinothalamic tract carry?
Where does it cross over?
Pain and Temperature
In the cord
Where in the cord can you find a third Lateral horn?
Thoracolumbar - Sympathetic motor neurones
Sacral - Parasympathetic motor neurones
Where in the Cord is there less grey matter?
In the thoracic region as it has less muscles, so fewer motor neurones are needed
What are the main differences in the Cord between levels C5 and L5?
- More white matter at C5 as it has to carry more neurones than at lower levels
- C5 is more oval and just bigger
