EXAMINATION OF CO-ORDINATION
Objectives:
At the end of this session each student will be able to:
1. List normal and abnormal cerebellar functions.
2. Examine co-ordination function of cerebellum.
3. Describe findings of co-ordination functions of the cerebellum.
4. Interpret findings of co-ordination function of the cerebellum.
J.J. Kambona (M.B.Ch.B;
M.Med)
Normal and abnormal functions of cerebellum:
A co-ordinated combination of a series of motor actions is needed to produce
a smooth and accurate movement. This requires integration of sensory
feedback with motor output. This integration occurs mainly in the
cerebellum.
The normal functions of the cerebellum:
Maintenance of posture and balance.
1
Co-ordination of rapid voluntary movements.
Abnormalities of the cerebellar functions are shown by the presence
of:
Tremors. Nystagmus.
Hypotonia. Abnormal movements.
Decreased deep tendon Disordered speech i.e.
reflexes. dysarthria.
In the presence of weakness, tests for co-ordination must be interpreted
with caution and are unlikely to be informative if there is significant
weakness.
What to do it:
Examination of co-ordination involves the examination of:
1. Upper limbs. 3. Trunk.
2. Lower limbs. 4. Gait.
How to do it:
1. Upper limbs:
A. Pronator test:
Ask the patient to hold his arms outstretched with his palms
pronated.
Ask him to close his eyes.
Tell the patient to keep his arms in this position.
Watch the hands for some seconds.
Push his arms up or down suddenly.
B. Finger-nose test:
Hold your index finger out about an arm’s length (≈ 50 cm) in
front of the patient.
Ask the patient to touch your finger with his index finger and then
touch his nose.
When he has done this correctly ask him to repeat this faster.
Watch for accuracy and smoothness of movement.
C. Repeated rapid alternating movements:
Ask the patient to pat one hand on the back of the other quickly
and regularly (demonstrate). Or
Ask the patient to twist his hand as if opening a door or
unscrewing a light bulb (demonstrate). Or
Ask the patient to tap the back of his right hand alternatively with
the palm and then the back of his left hand. Repeat with the right
hand (demonstrate).
2. Lower limbs:
Heel-sheen test:
2
Let the patient lie down.
Ask him to lift his leg and place the point of his heel on his knee and
then run it down the sharp part of his shin (demonstrated).
Watch for accuracy and smoothness of movement.
Do not allow the patient to run his heel back along his shin as this may
act as a guide-rail and can mask inco-ordination.
3. Trunk:
Ask the patient to sit up from lying without using his hands. Does he
fall to one side? Or
Heel-toe test: Ask the patient to walk along the straight line
(demonstrate).
What you find:
Pronator test:
o The upper limbs return rapidly to position: Normal.
o The upper limbs oscillate up and down several times before coming
to rest: Cerebellar disease.
Finger-nose test:
o The patient is able to complete the task quickly and accurately:
Normal.
o The patient develops tremors as his finger approaches its target.
This is called ‘intentional tremors’.
o Finger may overshoot its target; this is called ‘past pointing’ or
‘dysmetria’. It suggests cerebellar disease.
Repeated rapid alternating movements:
There is a disorganization of the movements of the hands and the
elbows which takes wider excursions than expected with irregularity of
the movements, which are performed without rhythm.
This disorganization of movements is called ‘dysdiadochokinesia’ and
suggests cerebellar disease.
Heel-shin test:
There is disorganization of the movement with the heel falling off the
anterior part of the shin, knee falling from side to side.
The finger-nose and heel-shin test can be used as an indication of loss
of joint position sense.
Trunk:
Patient is unable to sit from lying without falling to one side or unable
to walk along the straight line without falling. This is called Truncal
ataxia and is associated with gait ataxia.
3
What it means:
Unilateral incoordination suggests ipsilateral cerebellar syndrome.
Common causes:
o Demyelination. o Vascular disease.
o Rare:
Head injury.
Brain tumour. Brain abscess.
Bilateral incoordination suggests bilateral cerebellar syndrome.
Common causes:
o Demyelination. o Vascular disease.
o Drugs e.g. anticonvulsants, alcohol etc.
o Rare:
Hypothyroidism. Paraneoplastic
syndrome.
Hereditary cerebellar degenerations.
Truncal ataxia, gait ataxia, without limb incoordination suggests midline
cerebellar syndrome. The common cause is lesions of cerebellar vermis
(the same as those for bilateral cerebellar syndrome).
References:
1. Geraint fuller. Coordination; Neurological examination made easy. 3 rd
edition, page: 185-189.
2. Hutchison R. Examination of the central nervous system. Hutchison’s
clinical methods. 21st edition, chapter 11, page 219-281.
3. Essential of clinical medicine, page: 89-129.
4. Neurological disorders. The Merck manual of diagnosis and therapy. 17 th
edition, page 1341-1502.
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