Disorders of Spine

Question 1

What way are the sensory fibres arranged within the spinal cord?

Answer 1

Fibres carrying cervical information are closest to the dorsal horn
then thoracic, then lumbar then sacral around around edge of the cord

Question 2

What way are the motor fibres arranged within the spinal cord?

Answer 2

Descending fibres carrying information to cervical area closest to anterior horn
then thoracic, lumbar then sacral
sacral found most medially

Question 3

What are the two sensory systems?

Answer 3

dorsal column system

spinothalamic tract

Question 4

How many neurones are needed in each sensory systems?

Answer 4

• always use three neurones
• the first coming from dorsal root ganglion
• last neurone always in thalamus (contralateral side of dorsal)

Question 5

Describe the Dorsal column tract?

Answer 5

• neurone enters through dorsal root ganglion
• travels immediately up dorsal column
• reaches medulla where second neurone synapses
• second neurone crosses over and travels to thalamus
• third = thalamus > cortex

Question 6

What type of information is carried by the Dorsal column tract?

Answer 6

Fine touch and proprioception

Question 7

Describe the difference in spinothalamic tract compared to DCT?

Answer 7

• first neurone synapses with second neurone in the dorsal horn of spinal cord
• second neurone crosses immediately
• synapses with third neurone in thalamus which travels to cortex

Question 8

What type of information is carried by the spinothalamic tract?

Answer 8

Pain and temperature

Question 9

How many neurones are involved in each motor pathway?

Answer 9

Two

Question 10

Describe the motor pathway?

Answer 10

• first neurone starts in pyramidal cells in cortex
• travels through internal capsule and brainstem
• at end of brainstem crosses over
• enters spinal cord where it will synapse with second neurone in ventral horn

Question 11

What are the two descending motor pathways?

Answer 11

Lateral corticospinal tract

rubrospinal tract

Question 12

What information does rubrospinal tract carry?

Answer 12

• motor information to the toe

- works by suppressing the second neurone (which is why toe curls if damage to rubrospinal)

Question 13

What other words can be used to describe the upper and lower motor neurone lesion?

Answer 13

Upper = central or first

Lower = peripheral or second

Question 14

What motor changes will occur with a UMN or LMN lesion?

Answer 14

reduced/ missing power

Question 15

What muscular tone changes will occur with a LMN and UMN lesion?

Answer 15

LMN - Decreased muscular tone

UMN - Increased (spastic)

Question 16

How does muscular tone change in Parkinsons’s?

Answer 16

get rigid muscular tone

Question 17

What does spastic tone mean?

Answer 17

• if continuously contract muscle will eventually collapse muscle so for example drop arm

Question 18

What commonly occurs to deep tendon reflexes in UMN or LMN lesions?

Answer 18

UMN - Exaggerated, increased reflexogenic zone and polyclonal answers

LMN - Weak/missing

Question 19

What is polyclonal answer?

Answer 19

get multiple responses from one stimulation of reflex

Question 20

What is increased reflexogenic zone?

Answer 20

if you stimulate area near reflex will still get a response

Question 21

What pathological reflexes (shouldn’t be present) are present in UMN lesion?

Answer 21

Hoffman - flick finger middle finger will result in grasping motion of other fingers (Pos response)
Babinski - move finger up from bottom of sole of foot to top and toe will curl upward instead of down

Question 22

What pathological reflexes are present in LMN lesion?

Answer 22

none will display neither hoffman or babinski

Question 23

What are the spine enlargements?

Answer 23

1) cervical enlargement (C5-C8) - second neurone (where first neurone is travelling to reach) for the arms
2) Lumbar enlargement - second neurone for legs

Question 24

What are the possible causes of spinal injury?

Answer 24

• trauma
• herniated disc
• tumour
• infection

Question 25

What neurones are affected by high cervical (C1-C4) injury?

Answer 25

quadriplegia + sensation loss depending on which spinal cord segment affected e.g. C4 innervates shoulders and lower neck first neurone affected which means second neurone will also not receive signal

Question 26

What problems will a high cervical injury cause?

Answer 26

1) quadriplegia 2) sensation loss in dermatome of affected vertebrae 3) bladder retention / constipation 4) breathing problems

Question 27

Why is there breathing problems with high cervical lesions?

Answer 27

2nd neurone in thoracic region is for intercostal muscles signal going to the 2nd neurone is stopped at cervical region so unable to breath with intercostal muscles (can still breath with diaphragm but even diaphragm partially impaired)

Question 28

What neurones will be injured by a low Cervical injury (C5-T1)?

Answer 28

In lower limbs first neurone affected not second neurone | In upper limbs both first and second neurones damaged

Question 29

What problems occur with low cervical injury?

Answer 29

- weakness in upper limbs (flaccid not spastic) - Decreased tone upper limbs - lower limbs weakness (spastic) - bladder and bowel impairment - lose sensation in dermatome of spinal cord segment affected

Question 30

What is the difference in problems occurring in high and low cervical injury?

Answer 30

- breathing problems only in high cervical | - low cervical will cause flaccid weakness in upper limbs

Question 31

What problems occur with thoracic (T2-T12) injury?

Answer 31

- breathing problems (only breathe with diaphragm not chest) - lower limb paralysis (spastic) - bowel and bladder impairment

Question 32

When is paralysis spastic and when is it flaccid?

Answer 32

spastic when second neurone intact (2nd neurone still fires increasing tone) flaccid when both first and second neurone affected

Question 33

What problems can occur in lumbar enlargement injuries (L1-S1)?

Answer 33

- lower paraplegia (flaccid) - bowel and bladder impaired - lose sensation in corresponding dermatomes

Question 34

What problems can occur in injuries of Cauda Equina and S2?

Answer 34

- upper limbs intact - can have flaccid weakness of lower limbs - impairment of bowel and bladder (peripheral) - sensation lose in corresponding dermatome (saddle region) - loss of anal tone

Question 35

When will there be peripheral impairment of bladder and bowel and when will there be central?

Answer 35

Peripheral only in S2 and cauda equina injury (leaking of bladder/bowel) rest of spine will result in central

Question 36

What is the cauda equina?

Answer 36

axons of second neurone

Question 37

What is Brown Sequard syndrome?

Answer 37

- injury involves only one side of cord (hemicord lesion) - half of body will then be affected - symptoms depend on location of lesion

Question 38

In brown sequard syndrome which symptoms will be ipsilateral and contralateral?

Answer 38

``` ipsilateral (side of lesion) - paralysis - deep sensation - proprioception Contralateral (opposite) - pain - temperature ```

Question 39

Which spinal cord vertebrae correspond with which spinal cord segments?

Answer 39

(most are slightly offset so C8 segment is not at C8 vert) C4-C6 = +1 (corresponding seg is one higher) C7-T5 = +2 T6-T11 = +3 T12 = +4 L1 = conus medullaris L2-S2 = Cauda equina