Spinal Cord Anatomy Review

Question 1

what level does the spinal cord end at?

Answer 1

L1-2

Question 2

describe the blood supply to the spinal cord

Answer 2

1. anterior spinal artery
2. posterior spinal artey

Question 3

list the ascending sensory tracts

Answer 3

1. Dorsal Column - Medial Lemniscus Pathway
2. Anterolateral Pathway
3. Spinocerebellar Pathway

Question 4

describe the dorsal column-medial lemniscus pathway?

Answer 4

1. conscious proprioception, vibration, light and discriminative touch
2. second order neurons cross in caudal medulla in internal arcuate fibers

Question 5

describe the anterolateral pathway

Answer 5

1. pain temperature, crude touch
2. second order neurons cross at level of spinal cord through anterior commisure

Question 6

describe the spinocerebellar pathway

Answer 6

1. unconscious proprioception from trunk and limbs
2. terminates in cerebellum

Question 7

list the descending tracts/pathways

Answer 7

1. lateral corticospinal tract
2. anterior corticospinal tract
3. rubrospinal tract
4. vestibulospinal tract
5. reticulospinal tract
6. tectospinal tract

Question 8

describe the lateral corticospinal tract

Answer 8

1. function → volitional movement of contralateral limbs
2. cross at pyramidal decussation and descend contralaterally

Question 9

describe the anterior corticospinal tract

Answer 9

1. function → control of bilateral axial and girdle muscles
2. descend ipsilaterally until level of spinal cord, at which point splits into bilateral innervation

Question 10

describe the rubrospinal tract

Answer 10

1. function → assist with LCST with descending drive for movement of contralateral limbs
2. originates in red nucleus, cross midbrain and descends contralaterally

Question 11

describe the vestibulospinal tracts

Answer 11

1. Medial VST
   
   • originates in rostral medulla, descending bilaterally to cervical region to control positioning of head and neck
2. Lateral VST
   
   • originates in pons, descends ipsilaterally down spinal cord to aide in truncal control and balance

Question 12

describe the reticulospinal tract

Answer 12

1. originates in both pontine and medullar RF and descends ipsilaterally to aid in posture and gait-related movements

Question 13

describe the tectospinal tract

Answer 13

1. originates in superior colliculus, crosses midbrain and descends contralaterally to upper cervical cord where it assists with coordination of head and eye movements

Question 14

what is the role of the sympathetic nervous system?

Answer 14

1. fight or flight
2. pupil dilation
3. bronchodilation
4. cardiac acceleration
5. digestive inhibition
6. piloerection
7. systemic vasoconstriction

Question 15

what is the role of the parasympathetic nervous system?

Answer 15

1. rest and digest
2. pupil constriction
3. bronchoconstriction
4. cardiac deceleration
5. digestion stimulation