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Flashcards in Spinal Cord 1 Deck (51):

What is the level most commonly injured in the spinal cord?

mid-low cervical spine followed by thoracolumbar junction (T9-L2)


Name the spinal vertebrae categories


The spinal cord is continuous with...


The spinal cord is ends where?

the medulla superiorly


around the 1st lumbar vertebra


The spinal cord occupies how much space of the vertebral canal?

anterior 2/3 


the spinal cord is protected by what?

the meningeal layers and CSF


where do we see enlargement in the spinal cord?

Cervical :  3rd Cervical to 2nd Thoracic vertebrae.

Lumbar :  10th to 12th Thoracic vertebrae.



why are there enlargments of the spinal cord?

To maintain sensory motor requirements of the extremities, i.e. arms and legs.


what part of the spinal cord is this?

cervical portion


what part of the spinal cord is this?



what part of the spinal cord is this?



what part of the spinal cord is this?



What connects the right and left sides of the spinal cord gray matter?

gray commissure


In thoracic nerve regions there is a lateral horn, also known as what?

intermediate gray horn or intermediolateral cell column.


on the left answer the type of nerve segment of the spinal cord and on the right fill, answer the name of the structure


Name what level of the cord 

Identify the exeternal and internal features of the cord


What is a herniated disc?

When the outer layer of the disc ruptures, allowing the

softer inner layer to ‘leak’ and press up against the

spinal cord or nerves.



What symptoms can result from a herniated disc?

What is the most common regions for herniated discs to occur?

  • pain,
  • numbness,
  • tingling 

Most common in lumbar/cervical regions.


Where do spinal nerves enter/exit the vertebra?


  • C1-C7 exit above their respective vertebra.
  • C8 exits below the C7 vertebra.
  • Thoracic, Lumbar and Sacral all exit below their respective vertebra


What does a ‘spinal segment’ consists of?


What do you call the spaces in the vertebra where the nerves pass through?

  1. two vertebra and the ligaments
  2. disc that join them


Neural foramina


How many spinal nerves are there and how are they arranged?

31 pairs of spinal nerves:

  • 8 Cervical
  • 12 Thoracic
  • 5 Lumbar
  • 5 Sacral
  • 1 Coccygeal


dorsal roots relay what type of information from the body?


ventral roots relay what type of information from the body?



motor output


What are the functional Components of Spinal Nerve Fibers divided into? Define each.

  • GSA:  General Somatic Afferent:  transmits sensory input from skin, muscle, bone and joints to CNS.
  • GVA:  General Visceral Afferent:  sensory input from visceral organs to CNS.
  • GSE:  General Somatic Efferent:  conveys motor output from ventral (anterior) horn motor neurons to skeletal muscle.
  • GVE:  General Visceral Efferent:  conveys motor output to smooth muscle and visceral organs.


identify the parts and where the corticospinal tract is

Also, tell if the H part is grey or white matter

H part = grey matter


The anterior grey horn contains what type of neurons and for what? where do they exit through?

  • motor neurons to innervate skeletal muscle these exit through the anterior roots of the spinal nerves as alpha efferents.
  • Smaller motor neurons in this region leave via the same route, and innervate intrafusal muscle fibers.  These are gamma efferents.


the fasciculus gracilis is needed for what?

and the fasciculus cuneatus

control of legs

control of arms


Identify the Medial and lateral groups of motor neurons (anterior horn)

Medial motor neuron = 12

Lateral motor neuron = 6


Identify the areas


which controls appendicular musculature and which controls axial musculature?

L = appendicular musculature

M = axial musculature


What are lower motor neurons (LMN)?

The motor neurons with cell bodies in the anterior

horns that innervate musculature 



What are Upper Motor Neurons (UMN)?

The motor neurons that connect the ‘brain’ to the

LMN’s are called



What are the nerve cell groups of the Posterior grey horn? what do each control?

  • Marginal layer:  receives type A fibers, pain.
  • Substantia gelatinosa:  receives information on pain, temperature, and touch, predominantly C type fibers.
  • Nucleus proprius:  Receives both A and C fibers from spinothalamic tracts.
  • Nucleus dorsalis (Clark’s column):  proprioception from spinocerebellar tracts, and also from dorsal columns.
  • Visceral afferent nucleus:  receive visceral afferents.


The White Matter of the Spinal Cord is divided into what? Name them,


anterior, lateral, and posterior white columns.


What is the Spinal cord blood supply?

how much does each part contribute to supplying the cord?

  • Anterior spinal artery for anterior 2/3 of cord.
  • Posterior spinal arteries (2) for posterior 1/3 of cord.
  • Segmental/radicular arteries: branches from vertebral/subclavian supplement blood supply in cervical regions, branches from descending aorta for thoracic/lumbar regions.  The great anterior radicular artery supplies most of the blood in the lower cord.  



Anastomosis of radicular/spinal arteries is widespread  and is called what?

arterial vasocorona.


what are Spinal Cord Reflexes?

  • are ‘spinally mediated’, meaning they occur at the level of the spinal cord. 
  • remain intact below the level of a spinal cord lesion (altered, but intact).



name 3 spinal cord reflexes?

  1. Stretch (deep tendon) reflex
  2. Flexor withdrawal reflex:
  • Protective Reflex

  • pain) causes withdrawal of limb

  • may happen with crossed extensor reflex

    3.  Crossed extensor reflex: 

  • contralateral limb is extended to help support body


What damage or lesions are the anterior and posterior roots prone to?


Due to their entry/exit points through the vertebral foramina, the anterior and posterior roots are susceptible to:

  • compression of the spinal cord,
  • herniated discs,
  • fractures,
  • dislocation,
  • vertebral tumors,


what can we expect to see in a posterior root lesion?

Sensory loss from the corresponding dermatome...but could initially cause pain in the affected area, both skin and muscle.


what can we expect to see in a anterior root lesion?

paralysis of the muscle innervated by that root, with possible partial paralysis of muscle(s) partially innervated by that root.  Muscle atrophy (due to wasting) will occur.


What is Tabes Dorsalis?

Syphilis or neurosiphilitic lesion that can cause damage/lesion to the dorsal root at the point of entry into the spinal cord.


Tabes dorsalis occurs mostly in what regions?

How do patients with Tabes dorsalis walk?

 thoracic/lumbar regions = lower extremities


with a slapping gait or by slapping the foot on the ground


what are the symptoms of Tabes Dorsalis?

  1. Stabbing pains in lower limbs (beginning of disease)
  2. Hypersensitivity to touch, heat, cold (beginning of disease)
  3. Loss of sensation in skin and trunk
  4. Loss of awareness of a full bladder
  5. Loss of proprioceptive information
  6. Loss of deep pain sensation
  7. Ataxia of lower limbs
  8. Hypotonia of lower limbs
  9. Loss of reflexes


What is Ataxia?

what is Hypotonia?

  • Difficulty in coordinating muscle movements
  • Reduced muscle tone


Why will there be hypotonia and ataxia in tabes dorsalis?

due to loss of proprioceptive information from skeletal muscles, joints, and tendons.


what is a tabetic gait?

Loss of reflexes:  Stretch and tendon reflexes (biceps, knee-jerk, etc) have both a sensory and motor component.  The syphilitic lesion in Tabes Dorsalis interrupts the afferent (sensory) part of this reflex arc.


What is ALS (Amyotrophic Lateral Sclerosis)?


What symptoms can be expected with ALS?


The majority of ALS cases start with what type of symptoms?


Most patients die of what?

- Degeneration of both UMN (specifically the corticospinal tract) and LMN’s.

  • Loss of voluntary control of muscles,
  • loss of bowel and bladder control. 
  • Eye muscles usually, but not always, spared.
  • Cognition and ANS usually intact.

- 75% start with limb onset

- respiratory distress




What is Poliomyelitis?


what are the symptoms?

Degeneration of LMN’s (mostly spinal, onlyoccasionally bulbar)


  • ‘flaccid’ paralysis
  • atrophy.



ALS patients have a pseudobulbar effect, what is this?

they will have uncontrollable crying or laughing for no reason whatsoever


"reflexive tear or laughing"


What is the romberg test?

tell patient to close eyes, and if they have dorsal column problems or cerebellar, they have no propioception and fall; can also be tested in dark rooms


argyl robertson pupil's are usually found in what disease?

in tabes dorsalis


sudden symptoms are usually related to what problem?

when there is bilateral symptoms what arteries could explain it?


Anterior Spinal Artery or basilar