Chapter 4: Spinal Cord (continued)

Question 1

The fasiculus cuneatus carries fibers from what spinal cord segments?

Answer 1

T5 and up

Question 2

The DCML pathway is located in what part of the spinal cord?

Answer 2

dorsal columns

Question 3

The fasiculus gracilis carries fibers from which spinal cord segments?

Answer 3

T6 and below

Question 4

Where in the thalamus are the 3rd neurons of the DCML?

Answer 4

ventropostero-lateral nucleus VPL

Question 5

What sensations are loss with damage to the DCML?

Answer 5

• joint position sensation
• vibratory and pressure sensations
• 2 point discrimination
• loss of ability to identify the characteristics of an object (asterognosis) (consistency, form, and shape)

Question 6

How is Romberg sign tested?

Answer 6

asking the patients to place their feet together. If there is marked deterioration of posture (if patient sways) with eyes closed, this is a positive Romberg sign (DC lesion)

If patent has balance problems and tends to sway with eyes open = cerebellar damage

Question 7

What sensations does the anterolateral pathway send?

Answer 7

pain, temperature, and crude touch sensations from the extremities and trunk

Question 8

What is another name for the anterolateral system?

Answer 8

spinothalamic tract

Question 9

Lissaur tract?

Answer 9

tract taken by anterolateral dorsal root fibers where they ascend or descend the spinal cord 1-2 segments down or up in the spinal cord

Question 10

Where is the ventral white commissure located?

Answer 10

below the central canal of the spinal cord

Question 11

Where do anterolateral system fibers cross the midline?

Answer 11

in the ventral white commisure

Question 12

Where in the thalamus does the spinothalamic tract terminate?

Answer 12

in the VPL nucleus of the thalamus

Question 13

Cells from the VPL that have received spinothalamic tract cords send pain and temperature information to which part of the brain?

Answer 13

primary somatosensory cortex in the postcentral gyrus

Question 14

What sensory information does the spinocerebellar tract carry?

Answer 14

unconscious proprioceptive input from muscle spindles and GTOs to the cerebellum where this information is used to help monitor and modulate movements

Question 15

What are the 2 major spinocerebellar pathways?

Answer 15

• dorsal spinocerebellar tract
• cuneocerebellar tract

Question 16

The dorsal spinocerebellar tract carries information from what part of the body?

Answer 16

carries input from the lower extremities and lower trunk

Question 17

The cuneocerebellar tract carries information from what part of the body?

Answer 17

carries proprioceptive input to the cerebellum from the upper extremities and upper trunk

Question 18

Where are the cell bodies of the dorsal spinocerebellar tracts found?

Answer 18

in Clarke’s nucleus, which is situated in the spinal cord from T1 to L2

Question 19

Where are the cell bodies of the cuneocerebellar tract found?

Answer 19

in the medulla in the external cuneate nucleus

Question 20

What is the most common hereditary condition involving degeneration of the spinocerebellar pathways?

Answer 20

Friedreich ataxia

Question 21

What are the areas of the spinal cord affected by Friedreich ataxia?

Answer 21

spinocerebellar tracts, dorsal columns, corticospinal tracts, an cerebellum

Question 22

How to identify a cord section: If there is a large ventral horn?

Answer 22

C5 -T1 or L2 - S2

Question 23

How to identify a cord section: If there is not a large ventral horn?

Answer 23

T1-L1, C1-C4

Question 24

How to identify a cord section: If both dorsal columns are present.

Answer 24

above T5

Question 25

How to identify a cord section: If both dorsal columns are not pressent?

Answer 25

below T5

Question 26

How to identify a cord section: If there is a lateral horn?

Answer 26

T1 - L2

Question 27

How to identify a cord section: If lateral horns are not present?

Answer 27

C1 - C8 or L3 - S5

Question 28

What is Brown-Sequard Syndrome?

Answer 28

hemisection of the cord causing lesion of each of the 3 main neural systems

Question 29

What is a hallmark sign of Brown Sequard syndrome?

Answer 29

patient presents with 2 ipsilateral signs and 1 contralateral sign

Question 30

What are the 3 Ps of Tabes Dorsalis?

Answer 30

paresthesias (pins-and-needles sensations), pain, polyuria | also will have Romberg sign

Question 31

Spastic bladder results from lesions found where in the spinal cord?

Answer 31

lesions of the spinal cord above the sacral spinal cord levels

Question 32

The pathogenesis for spastic bladder?

Answer 32

results from lesions of the spinal cord above the sacral spinal cord levels

Question 33

Pathology of polio?

Answer 33

results from a relatively selective destruction of lower motorneurons in the ventral horn by poliovirus

Question 34

Symptoms of polio

Answer 34

a. flaccid paralysis b. muscle atrophy c. fasciculations d. areflexia

Question 35

What levels of the spinal cord is polio typically found?

Answer 35

lumbar levels

Question 36

What does ALS stand for?

Answer 36

amyotrophic lateral sclerosis

Question 37

What is another name for ALS?

Answer 37

Lou Gehrig disease

Question 38

What levels of the spinal cord does ALS typically affect?

Answer 38

begins at cervical levels of the cord and progress either up or down the cord

Question 39

ALS symptoms.

Answer 39

a. progressive spinal muscular atrophy (ventral horn) b. primary lateral sclerosis (corticospinal tract) - spastic paralysis in lower limbs - increased tone and reflexes - flaccid paralysis in upper limbs c. Common in cervical enlargment

Question 40

What part of the spinal cord does occlusion of the ASA affect?

Answer 40

ASA (anterior spinal artery) interrupts blood supply to the ventrolateral parts of the spinal cord

Question 41

What major tracts of the spinal cord are affected with occlusion of the ASA?

Answer 41

corticospinnal tracts and spinothalamic tracts

Question 42

What is syringomyelia?

Answer 42

a disease characterized by progressive cavitation of the central canal

Question 43

What spinal cord levels are typically affected when one has syringomyelia?

Answer 43

usually in the cervical spinal cord level

Question 44

Horner syndrome manifestation?

Answer 44

ptosis miosis anyhydrosis

Question 45

Symptoms of syringomyelia?

Answer 45

a. bilateral loss of pain and temperature at the level of the lesion c. as disease progresses, there is muscle weakness; eventually flaccid paralysis and atrophy of the upper limb muscles due to destruction of ventral horns

Question 46

What is Tabes dorsalis a manifestation of?

Answer 46

neurosyphilis

Question 47

Pathology of Tabes dorsalis?

Answer 47

causes bilateral degeneration of the dorsal roots and secondary degeneration of the dorsal columns

Question 48

What are symptoms of Tabes Doralis?

Answer 48

a. "paresthesias, pain, polyuria" b. associated with late-stage syphilis, sensory ataxia, positive Romberg sign: sways with eyes closed, Argyll Robertson pupils, suppressed reflexes c. common at lumbar cord levels

Question 49

Pathology of atonic bladder?

Answer 49

* results from lesions to the sacral spinal cord segments of sacral spinal nerve roots * loss of pelvic splanchnic motor innervation with loss of contraction of the detrusor muscle results in a full bladder with a continuous dribble of urine from the bladder

Question 50

Pathology of infantile bladder?

Answer 50

Developmental Immaturity The bladder behaves as if it is still in the developmental phase, commonly seen in infants where voiding is involuntary and reflexive. There is a lack of proper maturation of: Cortical control: Necessary for voluntary urination. Neural pathways: Specifically the pontine micturition center, which coordinates bladder and sphincter function.

Question 51

Syringomyelia may present with what other condition?

Answer 51

Arnold-Chiari I malformation

Question 52

What is the buzz word for pain caused by syringomyelia?

Answer 52

"belt-like" or "cape like" loss of pain and temperature

Question 53

When is subacute combined degeneration typically seen?

Answer 53

in cases of B12 deficiency sometimes related to pernicious anemia

Question 54

Where is the myelin loss in subacute combined degeneration found?

Answer 54

patchy losses of myelin in dorsal columns and lateral corticospinal tract

Question 55

What are the symptoms of subacute combined degeneration?

Answer 55

a. vitamin B12, pernicious anemia b. demyelination of the: - dorsal columns (central and peripheral myelin) - spinocerebellar tracts - corticospinal tracts (CST) c. upper thoracic or lower cervical cord.

Question 56

Symptoms of ASA occlusion?

Answer 56

a. DC spared b. all else bilateral signs c. common at mid thoracic levels d. spastic bladder

Question 57

Brown Sequard Syndrome symptoms.

Answer 57

a. DC: ipsilateral loss of position and vibratory senses at and below level of the lesion b. spinothalamic tract: contralateral loss of pain and temp 1-2 segments below lesion and ipsilateral loss at the level of the lesion c. CST: ipsilateral paresis below the level of the lesion d. LMN: flaccid paralysis at the level of the lesion e. descending hypothalamics: ipsilateral Horner syndrome (if cord lesion is above T1)