L1 Cerebellum Disorders

Question 1

Function of normal motor system

Answer 1

Voluntary movements, facilitated by motor plan from cortex, delivered by LMN and sensory input

Question 2

Function of cerebellum

Answer 2

1. integrates sensory and other inputs from multiple regions of cortex and four spinal cord pathways
2. (Inferior olivary nucleus) Compares the efferent and afferent copies to calculate motor error, and sends those errors back, updating the motor plan

Question 3

Efferent copy of information

Answer 3

copy of motor plan from M1

Question 4

Afferent copy

Answer 4

sensory info relaying what happened in periphery during task

Question 5

Cerebellum uses info that it receives to…

Answer 5

1. smoothly coordinate ongoing movements
2. coordinate the sequencing of voluntary muscle contraction
3. contribute to motor planning
4. contribute to motor learning
5. contribute to language, decision making, affect

Question 6

Peduncles

Answer 6

are how info travels in and out of cerebellum

Question 7

Lateral hemisphere of cerebellum

Answer 7

helps with motor planning for extremities

influences the lateral corticospinal tract

Question 8

Intermediate hemisphere of cerebellum

Answer 8

function: distal limb coordination

influences lateral corticospinal tract, rubrospinal tract

Question 9

Vermis and Flocculonodular lobe

Answer 9

function: proximal limb and trunk coordination. balance and VOR

influences anterior corticospinal tract, reticulospinal tract, vestibulospinal tract, tectospinal tract, MLF

Question 10

Lateral motor systems

Answer 10

lateral corticospinal tract
rubrospinal tract

Question 11

Medial Motor Systems

Answer 11

anterior corticospinal tract
reticulospinal tract
M/L vestibulospinal tract
tectospinal tract

impacted by vermis and flocc. nodules

Question 12

Cerebellar Dysfunction

Answer 12

causes ataxia or a lack of order

movements have abnormal timing, trajectories through space

Question 13

Ataxia

Answer 13

disordered contractions of agonist and antagonist muscles and resulting lack of coordination between movements at different joints seen in patients with cerebellar dysfunction

Question 14

Dysmetria

Answer 14

abnormal trajectories through space. Undershoot or overshoot

Question 15

Dysrhythmia

Answer 15

abnormal timing and rhythm of movements

Question 16

Lateral lesions

Answer 16

present with ipsilateral deficits

Question 17

Lesions of vermis

Answer 17

have bilateral deficits

Question 18

Truncal ataxia

Answer 18

lesions affecting the cerebellar vermis primarily affect the medial motor systems

results in drunk like gait

Question 19

Appendicular ataxia

Answer 19

lesions affecting the intermediate and lateral cerebellar regions affect the lateral motor systems

Question 20

Sensory ataxia

Answer 20

damage to the lateral columns leading to a lack of peripheral proprioceptive input

improves with visual feedback

Question 21

Dysdiadochokinesia

Answer 21

abnormalities of rapid alternating movements

Question 22

Postural tremor

Answer 22

tremor seen when the limb muscles are activated to hold a particular position

Question 23

Essential tremor

Answer 23

low amplitude postural tremor

Question 24

Action or intention tremor

Answer 24

appendicular ataxia during movements toward a target

Question 25

Ocular dysmetria

Answer 25

overshoot or undershoot of the target during saccades

Question 26

Nystagmus

Answer 26

rhythmic beating that can change direction, occasionally upbeating with cerebellar dysfunction

Question 27

Cerebellar S/S: Eye

Answer 27

Ocular Dysmetria Nystagmus inability to suppress VOR

Question 28

Cerebellar Tremors

Answer 28

postural essential action or intention

Question 29

Cerebellar S/S Speech

Answer 29

-speech has ataxic quality with fluctuations in rate and volume -speech may be slurred and difficult to understand

Question 30

Possible pathologies for Cerebellar disorders

Answer 30

Developmental Metabolic Progressive Degenerative Trauma Stroke Tumor

Question 31

Friedrich's Ataxia

Answer 31

(progressive degenerative) -no medical cure -most common autosomal recessive disease -results in deficiency of frataxin -onset is at 15 yo -life expectancy is 37.5 yo

Question 32

Results of frataxin deficiency

Answer 32

-lesions in DRG, causing peripheral neuropathy -dentate nuclei -reduction in SC diameter, especially in DCML in spinocerebellar tracts -impacts on CV and endocrine systems

Question 33

CP of Friedrich's Ataxia

Answer 33

-hallmark feature is ataxia -peripheral neuropathy -absent LE reflexes -reduction of proprioception and vibration sense -LE weakness and pes cavus -DM -VO impairments -cardiomyopathy

Question 34

Ataxia is usually...

Answer 34

ipsilateral to side of a cerebellar lesion this is because pathways from cerebellum are double crossed

Question 35

Crossings of lateral motor pathways

Answer 35

First = cerebellar outputs exit in decussation of superior cerebellar peduncle in midbrain Second = corticospinal and rubrospinal tracts descend in the SC at the pyramids

Question 36

Lesions of lateral and intermediate hemispheres case

Answer 36

S/S of proximal and distal limbs, including ataxia, intention tremor, dysdiadochokinesia

Question 37

Midline lesions of cerebellar vermis or Flocculonodular lobes causes...

Answer 37

unsteady gait due to truncal ataxia and vestibulooccular dysfunction does not cause unilateral deficits b/c medial motor systems influence trunk bilaterally eye movements abnormalities and intense vertigo, nausea, vomiting due to connection to flocculonodular lobe

Question 38

Eye patching of impaired eye

Answer 38

gives it a rest and prevents fatigue and double vision

Question 39

Eye patching of non-impaired eye

Answer 39

to allow weaker eye an opportunity to work without the distraction of double vision

Question 40

Impairment Examination includes

Answer 40

appendicular ataxia truncal ataxia vestibular tests oculomotor tests

Question 41

Appendicular Ataxia Exam

Answer 41

finger to nose heel to shin rapid alternating movements toe tapping finger tapping indicates that proprioception is intact

Question 42

Truncal Ataxia Exam

Answer 42

Tandem Gait Romberg Test (not the best) Titubation Normal Gait

Question 43

Titubation

Answer 43

rhythmic tremor mainly of the head and/or upper trunk with a frequency of 3-4 cycles/second seen in any position or during activities

Question 44

Gait in cerebellar dysfunction

Answer 44

Wide-based, unsteady gait tandem gait will fall toward side of lesion

Question 45

Saccades for cerebellum

Answer 45

abnormal with present of undershoot or overshoot smooth pursuit would be abnormal with the presence of saccadic intrusions

Question 46

Nystagmus cerebellum results

Answer 46

might be present and would likely be direction changing

Question 47

Dorsal Column Lesion

Answer 47

visual feedback will improve ataxia no dizziness, vertigo, nausea loss of proprioception/touch

Question 48

Lacunar Stroke

Answer 48

can lead to ataxia hemiparesis syndrome combo of unilateral UMN signs and ataxia of same side

Question 49

Scale for the assessment and rating of ataxia (SARA)

Answer 49

8 item performance based scale, yielding a total score of 0 (no ataxia) to 40 (most severe) patient performs gait, stance, sitting, speech, finger chase, nose to finger, fast alternating hand movements, heel shin slide

Question 50

Cueing/Facilitation for Cerebellar Involvement

Answer 50

Use tactile, verbal, visual cues, fading over time use extrinsic cueing practice should be random, whole, and high repetition

Question 51

DOs of Cerebellar Ataxia Treatment

Answer 51

-proximal stability when necessary -start with lower degrees of freedom -external cues -high repetition practice -progress to targeting distal accuracy -compensatory strategies are OK

Question 52

DONTs of Cerebellar Ataxia Treatment

Answer 52

-start with work on distal accuracy -weight the limb for increased proprioceptive feedback -randomize practice -emphasize strength training (most have normal strength, but not good motor control)