CA

Question 2

Define Cerebellar Ataxia (CA)

Answer 2

Abnormal coordination due to damaged neurons in the cerebellum. Affects:

• speed
• amplitude
• accuracy
• force of movement

Question 3

Causes of CA (and 4 examples)?

Answer 3

Focal lesions (e.g. stroke, TBI, tumour and MS)

Question 4

Name the 3 functional divisions of the cerebellum and describe their functions

Answer 4

1) Vestibular cerebellum ? (balance) balance, eye movement
2) Cerebrocerebellum ? (planning) preparation, initiation, precision, timing, sequencing, coordination of movement
3) Spinocerebellum ? (execution) execution of limb movements, smoothness of muscle movements

Question 5

What roles does the cerebellum have?

Answer 5

1. Motor control regulation
2. Synergies
3. Intensity of movement
4. Movement to movement error correction
5. Timing and sequencing

Question 6

General function of the cerebellum

Answer 6

Dexterity and postural control

Question 7

Define ataxia

Answer 7

Lack of voluntary coordination of muscle movements

Question 8

Define

• Dysmetria
• Rebound phenomenon

Answer 8

Dysmetria ? lack of coordination typified by under/overshooting (not measuring distance correctly)

Rebound phenomenon ? slow antagonist action

Question 9

Define

• Dysdiadochokinesia
• Dysarthria
• Nystagmus

Answer 9

Dysdiadochokinesia ? inability to perform rapid alternating movements

Dysarthria ? poor coordination of speech production muscles

Question 10

Define

• Dyssynergia
• Nystagmus

Answer 10

Dyssynergia - poor coordination of timing onset and offset of ag/antagonists (loss of smoothness)

Nystagmus ? oscillating eye movement

Question 11

What are the main impairments in CA? (2)

Answer 11

Loss of dexterity/coordination etc

Loss of balance

Question 12

What are the main motor performance characteristics in CA?

Answer 12

Dysmetria
Rebound phenomenon
Dysdiadochokinesia 
Dyssinergia
Tremors
Dysarthria
Nystagmus

Question 13

How is CA assessed?

Answer 13

Dexterity tests
- Pronation/supination, postural sway, heel/shin, heel over foot, finger to nose/finger, rebound

• Functional assessment ? sitting, standing etc.

Question 14

Is a strength assessment usually necessary in CA?

Answer 14

NO

- Strength is usually unaffected in CA

Question 15

CA measures (6)

Answer 15

Measures (record accuracy)

• 10 m walk test (variable step lengths)
• TUG
• Step test
• Functional Reach
• 6 min walk
• 9 hole peg test

Question 16

Typical motor behaviours in CA

- restrictions (2), increases (2) and excessive (2)

Answer 16

Restricted

• amplitude of movement
• ROM (i.e. stiffness)

Excessive

• pre shaping and use of support surfaces during reaching (use of adaptive strategies)
• BOS, stepping and use of arms in walking

Increased

• speed and difficulty slowing when walking
• variability of performance

Question 17

Intervention considerations for CA

Answer 17

Considerations:

• Task specific, high reps
• May modify and add adaptive behaviours to make task easier with degenerative CA (e.g. multijoint training for recoverable, stabilize joints for degenerative)
• Train accuracy and speed
• Remember balance is a main impairment in CA (safety)

Question 18

CA research say about reaching?

Answer 18

Reaching

• Abnormally curved wrist path
• Better with joints fixed

Question 19

CA research say about gait?

Answer 19

Gait

• Less PF and knee yield
• More variable

Stepping over an obstacle
- more dysmetria than normal walking

Question 20

CA research on timing?

Answer 20

Heel raise

• same sequence but poor timing
• poor build up of EMG

Question 21

CA research on dual tasks?

Answer 21

Poor with addition of dual task

Question 22

CA research on training accuracy and balance/coordination?

Answer 22

Improved accuracy

Improved function and independent walking ability

Question 23

Degenerative CA training?

Answer 23

2hrs daily for 4ks PT/OT
= better (walking speed, less falls, ADLs)
= maintained at 12/24wks