Spinal Cord 2 Flashcards
The superficial dorsal horn consists of
Laminae 1 and 2
Grey matter is divided into
laminae of Rexed
Which laminaes of rexed are in the dorsal horn?
1-6
What does laminae 2 consist of?
Substantia gelatinosa of Rolando
Motor neurone cell bodies lie in
Laminae 9 in ventral horn
Extrafusal muscle fibres
Innervated by alpha motor neurones
Intrafusal muscle fibres
Innervated by gamma and beta motor neurones
Intrafusal muscle fibres constitute the _____ and are innervated by….
Muscle spindle, one sensory and one motor
Injury to periphery nerves is caused by
Lower motor neurone lesion
Symptoms of nerve injury
flaccid paralysis, rapid muscle
wasting, fibrillation and fasciculation
Location of primary afferent cell bodies
DRG
all primary afferents are
excitatory
________ allow excitatory primary afferents to inhibit ______ muscles
Inhibitory interneurones, antagonistic
Differences between lumbar and thoracic cord
Lumbar - thick grey matter - mn for limb
Thoracic- thin grey
In which laminae are motor neurones?
Laminae IX
Motor neurones in C8/T1 cord:
Pair 1 : trunk
Pair 4 : hand
Motor neurone in thoracic cord:
To sympathetic trunk
Motor neurones in sacral cord:
- interior MN - flexor mn
- Exterior MN - extensor mn
- Last pair - for foot
Cerebellar peduncles
Connect the cerebellum to the brain stem. There are six cerebellar peduncles in total, three on each side
(not seen in saggital)
Instructions to mn are carried from the
brain by descending tract
The corticospinal tracts arise in the _______ and end in the _______ (after crossing the midline).
cerebral cortex, spinal cord
Upper motor neuron lesion
occurs in the neural pathway above the anterior horn cell of the spinal cord or motor nuclei of the cranial nerves.
Upper motor neuron lesion symptoms
spastic paralysis, little muscle wasting, Babinsky sign
