Structure and Function of the Spinal Cord Flashcards

1
Q

The spinal cord connects directly to which part of the brain?

1 - cerebellum
2 - cerebrum
3 - midbrain
4 - brain stem

A

4 - brain stem
- medulla oblongata specifically

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2
Q

The spinal cord is directly attached to the brain stem, specifically the medulla oblongata. Where does the spinal cord extend down to?

A
  • extends through the cervical, thoracic and ends at the lumbar
  • L1 or L2
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3
Q

The spinal cord is directly attached to the brain stem, specifically the medulla oblongata. The spinal cord extends down to the lumbar region of the spine, specifically L1-L2. Here it narrows and forms what?

1 - conus medullaris
2 - cauda equina
3 - sacral plexus
4 - lumbar-sacral joint

A

1 - conus medullaris
- the bundled, tapered end of the spinal cord nerves

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4
Q

The spinal cord ends at lumbar region L1-L2 and forms the conus medullaris. The spinal nerves however continue beyond this throughout the lumbar, sacral and coccyx regions of the spine. What is this called?

1 - conus medullaris
2 - cauda equina
3 - sacral plexus
4 - lumbar-sacral joint

A

1 - cauda equina
- latin for horses tail

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5
Q

The spinal cord, like the brain has 3 meningeal layers. What are these 3 layers called?

A
  • dura mater
  • arachnoid mater
  • pia mater
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6
Q

The spinal cord, like the brain has 3 meningel layers. Label these 3 layers in the image below?

A

1 = dura mater
2 = arachnoid mater
3 = pia mater (highly vascular)

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7
Q

The same 3 meningeal layers that surround the brain, also surround the spinal cord. The pia mater layer directly layers the spinal cord and is highly vascularised. This layer thickens for what purpose and what is this called?

A
  • thickening forms the denticulate ligament
  • anchor pia to dura mater
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8
Q

The same 3 meningeal layers that surround the brain, also surround the spinal cord. Between the pia and arachnoid layers is a space containing a fluid. What is this space called and what is the fluid contained within this space?

1 - epidural space
2 - sub-arachnoid space
3 - epipia space
4 - arachnoid cavity

A

2 - subarachnoid space
- contains CSF

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9
Q

The dura mater is separated from the vertebral column by a space, what is this space called?

1 - epidural space
2 - sub-arachnoid space
3 - epipia space
4 - arachnoid cavity

A

1 - epidural space (epi = above and dural = dura mater
- contains lymphatics, nerve roots, blood vessels, adipose and connective tissue

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10
Q

Where the spine ends at L1-L2 is called the conus medullaris. Attached to the conus medullaris is a delicate strand of fibrous tissue, called what?

A
  • filum terminale
  • modification of the pia mater
  • acts to anchor the spinal cord
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11
Q

As there is CSF in the spinal cord, we tend to go below the spinal cord so not to damage the spinal cord. Where is this performed in adults and children?

1 - adults = T11-T12, children T10-T11
2 - adults = L3-L4, children T10-T11
3 - adults = L3-L4, children L4-L5
4 - adults = L3-L4, children L5-S1

A

3 - adults = L3-L4, children L4-L5
- essentially below where the spinal cord ends

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12
Q

What are the 4 main regions of the spine and how many vertebrae and nerves is contained within each, given that there are 31 spinal nerves in total.

A
  • cervical = 8
  • thoracic = 12
  • lumbar = 5
  • sacral = 5
  • coccygeal nerve = 1
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13
Q

How many pairs of spinal nerves are there?

A
  • 31 pairs
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14
Q

In the cervical part of the spine there are 7 vertebrae, but 8 pairs of spinal nerves. How do the nerves leave the cervical vertebrae given there are more pairs of nerves than there are vertebrae?

A
  • spinal nerves 1-7 leave above the vertebrae
  • spinal nerve 8 leaves below the vertebrae
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15
Q

Below cervical spinal nerve 8, where do all the nerves leave the vertebrae, above or below the vertebrae?

A
  • below the vertebrae
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16
Q

The spinal cord is connected to the periphery by the spinal nerves. Each pair of nerves has a nerve route at the front of the spinal cord and at the back. What are these nerves routes called?

A
  • dorsal (back) = afferent (sensory PNS to CNS)
  • ventral (front) = efferent (effects CNS to PNS)
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17
Q

What is grey and white matter in the spinal cord?

A
  • grey = neuronal cell bodes (H shaped)
  • white = myelinated axons
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18
Q

Label the different parts of the T2 aspect of the spinal cord numbered 1-6 using the labels below:

  • dorsal column
  • lateral horn
  • ventral horn
  • ventral column
  • dorsal horn
  • lateral column
A

1 - lateral horn
2 - dorsal horn
3 - dorsal column
4 - lateral column
5 - ventral column
6 - ventral horn

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19
Q

In different parts of the spinal cord there are some larger and some smaller H shaped grey matter in the middle of the spinal cord. Why does the amount of grey matter and size of the H differ along the spinal cord?

A
  • some parts require more cell bodies are there are more functions
  • hands vs the hips for example
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20
Q

The white matter in the spinal cord is myelinated axons. These are called what?

A
  • tracts or funiculi
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21
Q

The grey matter of the dorsal horn on the spinal cord serves what purpose?

1 - neuronal cell bodies receiving sensory information from PNS
2 - pre-ganglionic sympathetic neurons
3 - neuronal cell bodies carrying efferent signals from CNS to PNS

A

1 - neuronal cell bodies receiving sensory information from PNS

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22
Q

The grey matter of the lateral horn on the spinal cord is what?

1 - neuronal cell bodies receiving sensory information from PNS
2 - pre-ganglionic sympathetic neurons
3 - neuronal cell bodies carrying efferent signals from CNS to PNS

A

2 - pre-ganglionic sympathetic neurons

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23
Q

The grey matter of the ventral horn on the spinal cord is what?

1 - neuronal cell bodies receiving sensory information from PNS
2 - pre-ganglionic sympathetic neurons
3 - neuronal cell bodies carrying efferent signals from CNS to PNS

A

3 - neuronal cell bodies carrying efferent signals from CNS to PNS
- efferent, so effector nerves to perform an action

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24
Q

What are the layers of grey matter in the spinal cord called?

1 - laminae
2 - caniculi
3 - lamella
4 - fistulas

A

1 - laminae

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25
Q

The white matter of the spine are called tracts. As these tracts travel up the spine towards the brain, what happens to them before reaching the brain?

A
  • at some point they will cross over (decussate)
  • left hemisphere controls right side of body
  • right hemisphere controls right side of body
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26
Q

The white matter tracts in the spinal cord are grouped based on their function. Are the tracts in the dorsal, lateral and ventral ascending or descending?

A
  • dorsal = ascending (PNS to CNS)
  • lateral = both ascending and descending
  • ventral = descending (CNS to PNS)
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27
Q

Information that is carried along the ascending tracts of the spinal cord can be internal or external, what are these called?

A
  • external like feelings = exteroceptive
  • internal sensations like touch = proprioceptive
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28
Q

Most ascending tracts of the spinal cord work on 3 nerve circuit tracts, what are these called?

A

1 - first order neuron
2 - second order neuron
3 - third order neuron

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29
Q

Information that is transmitted along the ascending tracts of the spinal cord, specifically the dorsal columns is called what and carries what information?

A
  • conscious proprioception
  • light, touch and vibration
  • 2 point discrimination
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30
Q

Information that is transmitted along the ascending tracts of the spinal cord, specifically the spinocerebellar performs what functions?

1 - pain
2 - sensations
3 - unconscious proprioception
4 - muscle co-ordination

A

3 - unconscious proprioception
- some touch and vibration sensations
- spine to cerebellum

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31
Q

Information that is transmitted along the ascending tracts of the spinal cord, specifically the spinothalamic performs what functions?

1 - pain
2 - sensations including pain and temperature
3 - unconscious proprioception
4 - muscle co-ordination

A

2 - sensations including pain and temperature

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32
Q

Why is unconscious proprioception important?

A
  • allows the body to be aware of its position
  • tells you joint positions and helps co-ordinate movement
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33
Q

The dorsal columns can be divided into the cuneate fascilicus (Lateral) and the gracile fascilicus (medial). Where do each of these receive sensory information from?

A
  • cuneate fascilicus (lateral) = arms
  • gracile fascilicus (medial) = legs, think Grand for big as legs are bigger than arms
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34
Q

The dorsal columns can be divided into the cuneate fascilicus (Lateral) and the gracile fascilicus (medial). The cuneate fascilicus (Lateral) receives sensory information from the arms and the gracile fascilicus (medial) receives sensory information from the legs. These are first order neurons. Once they have received this sensory information they do not decussate at the spinal level and instead travel to a specific part of the brain, what is this?

1 - cerebellum
2 - pons
3 - medulla oblongata
4 - thalamus

A

3 - medulla oblongata

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35
Q

The dorsal columns can be divided into the cuneate fascilicus (Lateral) and the gracile fascilicus (medial). The cuneate fascilicus (Lateral) receives sensory information from the arms and the gracile fascilicus (medial) receives sensory information from the legs. These are first order neurons. Once they have received this sensory information they do not decussate at the spinal level, instead travel to the medulla oblongata in the brain stem. Which nuclei does the cuneate (Lateral) and gracile fascilicus synapse in the medulla oblongata?

1 - nucleus fascilicus for both
2 - nucleus cuneatus and nucleus gracilis
3 - nucleus fascilicus and nucleus gracilis
4 - nucleus cuneatus and fascilicus gracilis

A

2 - nucleus cuneatus and nucleus gracilis
- cuneate fascilicus (arms) = nucleus cuneatus
- gracile fascilicus (legs) = nucleus gracilis
- these tracts then decussate to opposite side and travel to vertebral cortex

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36
Q

The information that is brought into the spinal cord and into the dorsal column has a cell body, but this is not in the spinal cord. This is just outside the spinal cord contained within what?

A
  • dorsal root ganglion
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37
Q

The information that is brought into the spinal cord and into the dorsal column has a cell body, but this is not in the spinal cord. This is just outside the spinal cord called the dorsal root ganglion. What is the area called where the nerves from the dorsal root ganglion enter the spinal cord?

1 - tract of lissauer
2 - spinocerebellar tract
3 - track of fasicullis
4 - tract of lesser

A

1 - tract of lissauer
- nerves enter the grey matter and then the white matter before travelling to the medulla oblongata

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38
Q

Once the first order neuron travels from the ascending tracts from the dorsal columns and travels to the medulla oblongata, second order neurons leave the medulla oblongata, following decussation and travel to where?

1 - cerebellum
2 - pons
3 - medulla oblongata
4 - thalamus

A

4 - thalamus

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39
Q

Once the second order neurons have left the medulla oblongata they meet the third order neurons in the thalamus. Where do the 3rd order neurons then travel to in the brain?

A
  • somatosensory cortex
  • specifically boardman areas 1, 2 and 3
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40
Q

Once the second order neurons have left the medulla oblongata they meet the third order neurons in the thalamus before synapsing in the somatosensory cortex, specifically boardman areas 1, 2 and 3. What white tract bundle do they pass through to reach the somatosensory cortex?

1 - internal capsule
2 - corpus callosum
3 - tract of lisseur
4 - somatosensory tract

A

1 - internal capsule

41
Q

If a patient has a lesion on their spinal cord, this can cause problems below. Whether it is ipsilateral (same side) or contralateral (opposite side) depends on the tract and sensation. If there is a lesion on the right side of spinal cord at L5 what would happen to the sensations that are associated with the dorsal columns, such as conscious proprioception, vibration and fine touch sensation?

A
  • ipsilateral, so right sided sensations are lost below L5
  • decussation occurs at the medulla oblongata
42
Q

If a patient has a lesion on their spinal cord, this can cause problems below, such as loss of proprioception and loss of touch sensation. What is this called if it happens on one side of the body or both sides?

A
  • one side = unilateral dorsal column loss
  • two sides = bilateral dorsal column loss
43
Q

If a patient has a lesion on their spinal cord, this can cause problems below, such as loss of proprioception and loss of touch sensation. This can happen on one side, unilateral dorsal column loss or both sides, bilateral dorsal column loss. What are some common causes of this?

1 - multiple sclerosis and B12 deficiency
2 - guillian barre syndrome and B12 deficiency
3 - multiple sclerosis and guillian barre syndrome
4 - guillian barre syndrome and stroke

A

1 - multiple sclerosis and B12 deficiency

44
Q

Laughing gas is something that is used recreationally, but can be very dangerous. Why is this dangerous?

A
  • causes B12 deficiency (crucial for DNA and RNA synthesis)
  • leads to lesions in the spine
  • causes uni/bilateral somatosensory loss
45
Q

What information does the spinothalamic tracts transmit?

1 - unconscious proprioception
2 - pain, temperature, and crude touch
3 - conscious proprioception, vibration, fine touch (2 point discrimination)
4 - conscious and unconscious proprioception

A

2 - pain, temperature, and crude touch

46
Q

The Spinothalamic tracts transmits information relating to pain, temperature and crude touch. Where does the first order neuron in the spine start and finish?

A
  • begins at sensory receptor and synapses with the dorsal root ganglion
  • then synapses with the 2nd order neuron in the dorsal horn (grey matter)
47
Q

The Spinothalamic tracts transmits information relating to pain, temperature and crude touch. The first order nerve arises from the peripheries and finishes at the dorsal horn in the spine. Here is synapses with the second order neuron. Where does the second order neuron then travel to?

A
  • decussates the midline at the level of entry over to the anterior or lateral columns
  • anterior = pressure sensations and crude touch
  • lateral = pain and temperature
48
Q

The Spinothalamic tracts transmits information relating to pain, temperature and crude touch. The first order nerve arises from the peripheries and finishes at the dorsal horn in the spine where they synapse with second order neurons. These then cross the midline and travel up the Spinothalamic tracts to where?

1 - cerebellum
2 - pons
3 - medulla oblongata
4 - thalamus

A

4 - thalamus
- 3rd order neurons then leave thalamus, travel through the internal capsule to somatosensory cortex in brain
- boardman areas 1, 2 and 3

49
Q

In the Spinothalamic tracts first order nerve arises from the peripheries and finishes at the dorsal horn in the spine where they synapse with second order neurons. These then cross the midline and travel up the Spinothalamic tracts to the thalamus. If there is a lesion on the spine on the right side of a cervical vertebrae at C7, will this affect the left of right side of the body?

A
  • contralateral (opposite side, so left side) above where tract decussates
  • decussation is at level of spine, so affects opposite side of the body
  • if lesion is on the right side of spine, then left side is affected then
50
Q

What is a syrinx?

A
  • enlargement of the spinal cords central canal
  • increased CSF causes enlargement of central canal
  • as it enlarges it can impair spinal tracts
51
Q

A syrinx is a fluid-filled cavity/cyst within the spinal cord. This can enlarge, damaging your spinal cord and causing pain, weakness and stiffness, among other symptoms. Which ascending tract is a syrinx most likely to affect and why?

1 - spinothalamic as it decussates at the level of the syrinx
2 - spinocerebellar as it decussates at the level of the syrinx
3 - dorsal column as it decussates at the level of the syrinx

A

1 - spinothalamic as it decussates at the level of the syrinx
- decussates at the midline of the spine so will be impaired
- topography arrangement = medial to lateral: cervical, thoracic, lumbar and sacral
- affects arms first (cervical nerves) as their tracts are closer to the spinal canal (CSF) where syrinx forms
- as the syrinx enlarges the legs will be affected

52
Q

When a syrinx forms this can affect the Spinothalamic tracts but not the dorsal column pathway. Why is this?

A
  • syrinx affects the nerves close to spinal canal
  • dorsal column dose not decussate at the spinal cord, so unaffected
53
Q

Syrinx can affect the Spinothalamic tract but not the dorsal column tracts. This can cause dissociated sensory loss, what is this?

1 - loss of all sensory input
2 - loss of one or more senses, but some more than others
3 - no affect on sensory input, but muscle tone is lost

A

2 - loss of one or more senses, but some more than others
- BUT preservation of other senses
- spinothalamic tract is affected so loss of pain, BUT fine touch and proprioception are maintained as these belong to the dorsal tract

54
Q

Where does the Spinocerebellar tract run from and to?

A
  • spinal cord to cerebellum
  • neurons remain ipsilateral throughout
55
Q

What information does the Spinocerebellar tract transmit?

A
  • unconscious proprioception
  • messages from muscle spindles, Golgi tendon organs (posterior tract) and interneurons (anterior tract)
  • important in unconscious proprioception and smooth motor control
56
Q

How many neurons are involved in the Spinocerebellar tracts?

A
  • 1st and 2nd order neurons
57
Q

Spinocerebellar tracts only have 1st and 2nd order tracts. Where do the first order tract start and finish?

A
  • arises from muscle spindles and Golgi tendon organs
  • enters the dorsal root and synapses with 2nd order neuron
  • enters the anterior or lateral fasciculus and up to cerebellum
58
Q

Spinocerebellar tracts only have 1st and 2nd order tracts. Where does the 2nd order neuron start and finish?

A
  • starts synapse with 1st order neuron in dorsal horn
  • travels up to the cerebellum in the anterior or lateral fasciculus
59
Q

Spinocerebellar tracts only have 1st and 2nd order tracts. The 2nd order neuron starts at the synapse with 1st order neuron in dorsal horn and then travels to the cerebellum. Which tract does this travel up to the cerebellum?

A
  • anterior and ventral tracts
  • very fast transmission
60
Q

Do the Spinocerebellar tracts cross the spinal cord prior to reaching the cerebellum?

A
  • no
  • they are ipsilateral
61
Q

The descending tracts are important pathways, what are they though?

A
  • pathways by which motor signals are sent from the brain to via upper motor neurons to lower motor neurones
  • the lower motor neurones then directly innervate muscles to produce movement
62
Q

The pyramidal/corticospinal tracts is the descending tract that controls conscious fine conscious motor movement. Why is it called the pyramidal/corticospinal tract?

A
  • decussates at the pyramids in the medulla oblongata
  • originates in the pyramidal cells of the primary motor cortex
63
Q

The descending tracts are important pathways for motor function. What are the 2 groups they can be separated into?

A

1 - Voluntary control of movement = pyramidal/corticospinal tract
2 = Involuntary control of movement = Extrapyramidal tracts (4 in total)

64
Q

The descending corticospinal tract is a 2 neuron circuit. Where does the 1st order neuron begin?

A
  • cell body is in the cerebral cortex (Boardman areas)
  • passes through internal capsule (a white matter pathway, located between the thalamus and the basal ganglia)
65
Q

The descending corticospinal tract is a 2 neuron circuit. Where does the 1st order neuron end?

A
  • enter brain stem
  • 80% decussate in the medulla
  • 20% do not decussate in the medulla and remain
66
Q

Once the upper neuron (1st order) in descending corticospinal tract (CST) reaches the order in the spine where to which the nerves innervate the body, where will they enter?

A
  • 80% that cross the medulla into the lateral fasciculus and into the lateral ventral horn
  • 20% that do not cross the medulla, will travel in the anterior fasciculus and then into the ventral horn
  • here they BOTH innervate alpha and gamma motor neurons
67
Q

Once the upper neuron (1st order) in descending corticospinal tract (CST) reaches the order in the spine where to which the nerves innervate the body, they will enter the lateral (80% of CST) or anterior (20% of CST) fasciculus and then into the ventral horn of the spinal cord. What do they synapse with here?

A
  • lower motor (2nd order) neuron
  • alpha and gamma motor neurons
  • this neuron will then innervate target tissues
68
Q

The corticospinal tract is the pyramidal tract which leaves the cortex, decussates at the pyramids (80% do and 20% do not decussate) and travels in the lateral and anterior fasciculus, before synapsing in the ventral horn. Of the 80 and 20% that do and do not decussate, what parts of the the body do they innervate?

A
  • 80% that decussates travel in lateral fasciculus and innervate the distal muscles for fine motor movements
  • 20% that do not decussates travel in anterior fasciculus and innervate the axial muscles for fine large movements
69
Q

What do alpha and gamma motor neurons innervate?

1 - alpha = extrafusal muscle and gamma =intrafusal muscle
2 - alpha = intrafusal muscle and gamma =extrafusal muscle

  • extrafusal = muscle shortening (contract)
  • intrafusal = muscle spindles (proprioceptive)
A

1 - alpha = extrafusal muscle and gamma =intrafusal muscle

70
Q

Where can alpha (voluntary movement) and gamma (muscle spindles) neurons be located in the spinal cord as part of the descending corticospinal tract?

A
  • located in the grey matter
  • trunk, limbs, flexor and extensor muscles are all located in different regions
71
Q

If there is a lesion in the descending corticospinal tract that originates above or below the medualla oblongata will the symptoms present on the same or opposite side of the body?

A
  • above medulla = contralateral side of the body
  • below medulla = ipsilateral side (same side) of the body
72
Q

In upper motor nerve disorders, what clinical symptoms can be observed?

A
  • spasticity (stiff muscle tone) (loss of muscle reflex)
  • brisk reflexes (more than normal) (loss of golgi tendon relfex inhibition)
  • weakness
73
Q

In upper motor nerve disorders, what clinical symptoms can include spasticity (stiff muscle tone), brisk reflexes (more than normal) and weakness. What are some common causes of an upper motor nerve disorder?

A
  • stroke
  • multiple sclerosis
  • cord injury
  • compression on cord eg disc
74
Q

What can cause lower motor nerve disorders?

A
  • degeneration of/damage to lower motor neurons (in ventral horn or periphery)
  • for example Guillain-Barré syndrome
75
Q

Lower motor nerve disorders are caused by degeneration of/damage to lower motor neurons (in ventral horn or periphery). What are 2 common causes diseases that can cause this?

A

1 - Spinal muscular atrophy (A in image) (genetic defect in SMN-1 gene
2 - Guillain-Barré syndrome (B in image)

76
Q

Lower motor nerve disorders are caused by degeneration/damage to lower motor neurons (in ventral horn or periphery). What are some common clinical symptoms these patients present with?

A
  • flaccid paralysis (no muscle tone)
  • no tendon reflexes
  • muscle atrophy
77
Q

Motor neuron disease is a disease that causes deterioration of the corticospinal tract and the anterior horn of the spinal column. Does this affect the upper or lower motor neurons?

A
  • both upper and lower
78
Q

Motor neuron disease is a disease that causes deterioration of the corticospinal tract and the anterior horn of the spinal column that affects the upper or lower motor neurons and causes weakness. Is it always progressive and what is the life expectancy?

A
  • always progressive
  • 3-5 years
79
Q

In upper and lower motor signs, what are the common clinical differences to look for?

A
  • upper = stiffness, increases reflexes, weakness
  • lower = wasting, lack of tendon reflex and loss of muscle tone
80
Q

What are descending extrapyramidal tracts?

A
  • carry motor fibres from brain stem to spinal cord
  • carry non voluntary motor control
  • automatic control of muscles (muscle tone, balance, posture and locomotion)
81
Q

Why are descending extrapyramidal tracts called extrapyramidal?

A
  • they do not pass through the pyramids in medulla
82
Q

Where do all the descending extrapyramidal tracts originate from?

A
  • brainstem
83
Q

The descending Rubrospinal tract is one of the extrapyramidal tracts, but where in the brain stem does it originate from?

1 - red nucleus of midbrain
2 - caudate fasiculis
3 - gracillus fasiculus
4 - occulomotor nuclei

A

1 - red nucleus of midbrain

84
Q

The descending Rubrospinal tract is one of the extrapyramidal tracts, and originates in the red nucleus of the brain stem. Where does it end?

A
  • decussates in the midbrain
  • synapses with lower motor neuron at ventral horn
  • only travels to cervical spine
85
Q

The descending Rubrospinal tract is one of the extrapyramidal tracts, and originates in the red nucleus of the brain stem. It crosses to the opposite side of the body at the brain stem and synapses with the lower motor neuron at ventral horn. What movement is it important in the upper limbs?

A
  • synapses with cranial nerves V, VI and VII in cervical vertebrae
  • stimulates the flexor muscles of head and neck
86
Q

What is Brown Sequard Syndrome?

A
  • damage to the spinal cord
  • affects only one half of the spinal cord
  • one side works and other side does not
87
Q

In Brown Sequard Syndrome half of the spine does not work, but depending on the somatosensory input can affect how the patient is affected. For example if there is a lesion on the right side of a patient at T1 with Brown Sequard Syndrome and we want to know how pain, temperature and crude touch (all travel up the spinothalamic tract) are affected below the lesion on each leg, what will we see?

A
  • right leg would be ok
  • left leg would have loss of pain, temperature and crude touch
  • spinothalamic tract decussates at the level of the lesion
88
Q

In Brown Sequard Syndrome half of the spine does not work, but depending on the somatosensory input can affect how the patient is affected. For example if there is a lesion at T1 on the right side of a patient with Brown Sequard Syndrome and we want to know how proprioception, fine touch (tactile sensation) and vibration (all supplied by the dorsal columns) below the lesion on each leg, what will we see?

A
  • dorsal columns do not cross until they reach the medulla oblongata
  • so ipsilateral (right side of the body)
89
Q

In Brown Sequard Syndrome half of the spine does not work, but depending on the somatosensory input can affect how the patient is affected. For example if there is a lesion on the right side of a patient with Brown Sequard Syndrome and we want to know how strength will be affected on the patient?

A
  • corticospinal tracts innervate muscles
  • nerves change sides at medulla oblongata
  • weakness will be present on same that lesion is present
90
Q

When we talk about topography, which fasciculi tracts are organised with upper limbs organised closer to the spinal and which are organised with upper limbs furthest from the spinal cord?

A
  • dorsal tracts, spinothalamic and pyramidal tracts
    = lower limbs closer to central canal
91
Q

The extrapyramidal are all autonomous. What are the 4 extrapyramidal tracts? Label them in the image below using the labels below”

  • Reticulospinal
  • Vestibulospinal
  • Rubrospinal
  • Medullary-reticulospinal
A

1 - Vestibulospinal
2 - Ponto-Reticulospinal
3 - Rubrospinal
4 - Medullary-reticulospinal

92
Q

The vestibulospinal tract is one of the 4 extrapyramidal tracts. What is the overall function of this tract?

A
  • controls extensor muscles
  • posture muscles
  • balance
93
Q

The vestibulospinal tract is one of the 4 extrapyramidal tracts. It is innervated by the fastigual nucleus in the cerebellum that provides proprioceptive input about the bodies position and from the ear relating to acceleration and deceleration. What nuclei does this input synapse with in the medulla oblongata?

A
  • vestibular nuclear complex
94
Q

The reticulospinal tract is one of the 4 extrapyramidal tracts. What is the overall function of this tract?

A
  • controls flexor muscles
95
Q

The reticulospinal tract is one of the 4 extrapyramidal tracts that controls flexor muscles. Where does this tract begin in the brainstem?

A
  • reticular formation
  • runs throughout brain stem
96
Q

The ponto-reticular tract is one of the 4 extrapyramidal tracts. What is the overall function of this tract?

A
  • controls extensor movements of muscles
  • assists the vestibulospinal tract
97
Q

The reticulospinal tract is one of the 4 extrapyramidal tracts that controls extensor muscles and assists the vestibulospinal tract. Where does this tract begin in the brainstem?

A
  • reticular formation
  • runs throughout brain stem
98
Q

The rubrospinal tract is one of the 4 extrapyramidal tracts. What is the overall function of this tract?

A
  • stimulates the flexor muscles in head and neck
99
Q

The rubrospinal tract is one of the 4 extrapyramidal tracts that controls flexor muscles in the head and neck. Where does the tract begin?

A
  • red nucleus in the midbrain