Cerebellum examination

Question 1

what is the overall structure of the cerebellum examination?

Answer 1

1. general inspection
2. gait
3. Romberg’s test
4. speech
5. eyes
6. upper limbs
7. lower limbs

Question 2

what does DANISH stand for?

Answer 2

• dysdiadochokinesia
• ataxia (gait and posture)
• nystagmus
• intention tremor
• slurred, staccato speech
• hypotonia/heel-shin test

Question 3

what should be looked for in general inspection?

Answer 3

• abnormal posture
• speech abnormalities
• scars
• gait
• walking aids
• hearing aids
• prescriptions

Question 4

what is ataxia?

Answer 4

a neurological sign consisting of involuntary movements with an irregular oscillatory quality which interfere with the normal smooth trajectory of movement; can be truncal or appendicular

Question 5

what is truncal ataxia?

Answer 5

ataxia affecting proximal musculature that is involved in gait stability; caused by damage to the cerebellar vermis and associated pathways

Question 6

what is appendicular ataxia?

Answer 6

ataxia affecting musculature of the arms and legs involved in the control of limb movement; caused by damage to the cerebellar hemispheres

Question 7

what is involved in cerebellar degeneration?

Answer 7

progressive loss of Purkinje cells in the cerebellum

Question 8

what are some causes of cerebellar degeneration?

Answer 8

chronic alcohol abuse, nutritional deficiency, paraneoplastic disorders, neurological diseases

Question 9

what are some typical clinical features of cerebellar degeneration?

Answer 9

• broad-based ataxic gait
• truncal ataxia
• dysmetria
• nystagmus

Question 10

how do you perform Romberg’s test?

Answer 10

1. position yourself within arms reach of the patient
2. ask patient to put their feet together and keep their arms by their sides
3. ask them to close their eyes
4. positive sign = falling without correction; indicates unsteadiness is due to sensory ataxia (deficit of propioceptive or vestibular function, rather than cerebellar function)
5. swaying with correction is not a positive result and often occurs due to truncal ataxia

Question 11

how is speech assessed? what would speech be like in cerebellar pathology?

Answer 11

1. ask patient to repeat “British constitution” and “baby hippopotamus” or C,C,C,C or L,L,L,L
2. cerebellar lesions can cause ataxic dysarthria which can present as scanning speech (words broken down into separate syllables, separated by pauses and spoken with varying volume) and slurred speech

Question 12

what is assessed in the eyes?

Answer 12

1. nystagmus
2. dysmetric saccades
3. impaired smooth pursuit

Question 13

what is nystagmus?

Answer 13

involves repetitive, involuntary oscillation of the eyes and can be physiological or associated with cerebellar pathology

Question 14

how is nystagmus assessed?

Answer 14

1. ask patient to report any diplopia during the assessment
2. ask patient to look straight ahead and examine eyes in primary position. look for any abnormal movement
3. move your finger in a H pattern
4. look for multiple beats of nystagmus

Question 15

how can you describe nystagmus?

Answer 15

• direction: most nystagmus has a fast phase and slow phase; direction is defined by the direction of the fast phase (direction is towards side of lesion in cerebellar pathology)
• direction of gaze: horizontal or vertical gaze
• plane: beats in horizontal or vertical plane

Question 16

what direction is the nystagmus in cerebellar pathology?

Answer 16

direction is towards the side of the cerebellar lesion

Question 17

how do you assess dysmetric saccades?

Answer 17

1. position your hand 30cm to the side of your head
2. ask patient to look at your hand, then back to your nose. repeat on both sides
3. movement of eyes should be quick and accurate; in cerebellar lesions, there will be often be overshoot (eyes go too far past the target, then correct themselves back to the target; these are dysmetric saccades)

Question 18

how is smooth pursuit assessed?

Answer 18

1. when patient is tracking your finger, the eyes should move smoothly
2. in cerebellar lesions, pursuit can be jerky or saccadic

Question 19

what is assessed in the upper limbs?

Answer 19

1. finger-to-nose test
2. rebound phenomenon
3. tone assessment
4. dysdiadochokinesia

Question 20

how is the finger-to-nose test performed?

Answer 20

1. position your finger so the patient has to fully outstretch their arm to reach it
2. ask the patient to touch their nose with the tip of their index finger and then touch your fingertip
3. ask them to do this as fast as possible
4. presence of dysmetria and intention tremor suggests ipsilateral cerebellar pathology

Question 21

what is dysmetria?

Answer 21

lack of coordination of movement; they miss the target by over/undershooting

Question 22

what is intention tremor?

Answer 22

broad, coarse, low-frequency tremor that develops as a limb reaches the endpoint of a deliberate movement

Question 23

what is the rebound phenomenon?

Answer 23

reflex that occurs when a patient attempts to move a limb against resistance that has been suddenly removed

Question 24

how is rebound phenomenon assessed?

Answer 24

1. ask patient to close their eyes and position their arms outstretched in front of them with palms facing upwards
2. explain to the patient that you will apply downward resistance on each arm and they should maintain their arm position as you apply resistance
3. push downwards on one forearm and immediately remove resistance
4. observe movement
5. in healthy people, when the resistance is removed the limb moves a short distance upwards before antagonist muscles contract and move the limb back to the original position
6. exaggerated version suggests spasticity, complete absence suggests cerebellar disease

Question 25

how do you assess tone in the upper limbs?

Answer 25

1. assess tone in muscle groups of the shoulder, elbow and wrist on each arm, comparing sides as you go 2. support patient's arm by holding their hand and elbow 3. ask patient to relax and allow you to fully control arm movement 4. move muscle groups of shoulder (circumduction), elbow (flexion/extension), wrist (circumduction)

Question 26

how is dysdiadochokinesia assessed?

Answer 26

1. ask patient to place their left palm on top of their right palm 2. ask them to turn over their left hand and touch the back of it onto their right palm 3. ask them to return to the original position 4. repeat this as fast as possible 5. observe speed and fluency and repeat with other hand 6. patients with cerebellar ataxia may struggle and be slow and irregular

Question 27

what is assessed in the lower limbs?

Answer 27

1. tone 2. knee jerk reflex (L3,4) in each leg 3. heel-to-shin test

Question 28

how is tone assessed in the lower limbs?

Answer 28

1. assess tone in hip, knee and ankle muscles 2. roll each leg 3. lift each knee briskly off the bed (warn them first) and observe movement of leg; in patients with normal tone, the knee should rise while the heel remains in contact with the bed (would lift off bed if there's increased tone)

Question 29

how is the knee-jerk reflex (L3,4) assessed?

Answer 29

1. remove weight from lower limb by supporting it or asking them to hand their legs over side of bed 2. ensure leg is completely relaxed 3. tap patellar tendon with tendon hammer 4. if reflex is absent make sure they're fully relaxed and perform reinforcement manoeuvre

Question 30

how is the heel-to-shin test performed?

Answer 30

1. ask patient to place their left heel on their right knee and run it down their shin in a straight line 2. ask them to return to the starting position 3. repeat sequence in smooth motion until you tell them to stop 4. repeat assessment on other side 5. dysmetria suggests ipsilateral cerebellar pathology 6. weakness can also produce dysmetria, so power should be assessed before

Question 31

what further assessments and investigations should be suggested?

Answer 31

1. full neuro exam 2. neuoimaging 3. formal hearing assessment