The International Cooperative Ataxia Rating Scale (ICARS) (Trouillas et al.,1997) is a 100-point semi- quantitative scale. It is divided into four parts, on the basis of the compartmentalization of cerebellar symp- toms (Babinski & Tournay,1913):
1. Postural and stance disturbances (subscore: /34) 2. Limb movement disturbances (subscore: /52) 3. Speech disorders (subscore: /8)
4. Oculomotor deficits (subscore: /6)
Posture and Gait Score (total of scores A to G)
A. Walking capacities: 10-m test including half-turn, near a wall
0 Normal
1 Almost normal naturally, unable to walk with feet in tandem
2 Walking without support, but abnormal and irregular
3 Walking without support but with considerable staggering; difficulties in half-turn
4 Walking with autonomous support impossible;
episodic support of the wall for a 10-m test 5 Walking only possible with one stick 6 Walking only possible with two special sticks
or with a stroller
7 Walking only with accompanying person
8 Walking impossible, even with accompanying person (wheelchair)
SCORE ...
B. Gait speed: a preceding score of 4 or more gives directly a score of 4 in this test
0 Normal 1 Slightly reduced 2 Markedly reduced 3 Extremely slow
4 Walking with autonomous support no longer possible
SCORE ...
C. Standing capacities, eyes open
0 Normal, able to stand on 1 foot more than 10 1 Cannot stand on 1 foot more than 10 sec, butsec
can stand with feet together
2 Able to stand with feet together, but cannot stand with feet in tandem position
3 Able to stand in natural position without support, with no or moderate sway. Cannot stand with feet together
4 Standing in natural position without support, with considerable sway and corrections 5 Unable to stand in natural position without
strong support of one arm
6 Unable to stand at all, even with strong support of two arms
SCORE ...
D. Spread of feet in natural position without support, eyes open: patient is asked tofind a comfortable position, and the distance between the medial malleoli is measured.
0 Normal (#10 cm)
1 Slightly enlarged ($10 cm)
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Chapter 4 – Clinical scales
2 Clearly enlarged (between 25 and 35 cm) 3 Severely enlarged ($35 cm)
4 Standing in natural position impossible SCORE ...
E. Body sway with feet together, eyes open 0 Normal
1 Slight oscillations
2 Moderate oscillations (#10 cm at the level of head)
3 Severe oscillations with risk of fall ($10 cm at the level of head)
4 Immediate falling SCORE ...
F. Body sway with feet together, eyes closed 0 Normal
1 Slight oscillations
2 Moderate oscillations (#10 cm at the level of head)
3 Severe oscillations with risk of fall ($10 cm at the level of head)
4 Immediate falling SCORE ...
G. Quality of sitting position: on a hard surface, thighs together, arms folded
0 Normal
1 Slight trunk oscillations
2 Moderate oscillations of trunk/legs 3 Severe dysequilibrium
4 Impossible SCORE ...
Kinetic functions (total of scores H to N)
H. Knee-tibia test: patient in a supine position, head tilted. Patient asked to raise one leg and place the heel on the knee and then slide the heel down the anterior tibial surface of the resting leg towards the ankle. On reaching the ankle joint, the leg is again raised in the air to a height of about 40 cm, and the action is repeated. At least three
movements of each limb. Under visual guidance.
0 Normal
1 Lowering of heel in continuous axis, movement decomposed in several phases, without real jerks, or abnormally slow 2 Lowering jerkily in the axis
3 Lowering jerkily with lateral movements 4 Lowering jerkily with extremely strong lateral
movements or test impossible SCORE Right ...
SCORE Left...
I. Heel-to-knee test: the action tremor of the heel-to-knee test is specifically observed when the patient holds the heel on the knee for a few seconds before sliding down the anterior tibial surface under visual control.
0 No trouble
1 Tremor stopping immediately when the heel reaches the knee
2 Tremor stopping in less than 10 sec after reaching the knee
3 Tremor continuing for more than 10 sec after reaching the knee
4 Uninterrupted tremor or test impossible SCORE Right ...
SCORE Left...
J. Finger-to-nose test: subject sitting on a chair.
Hand is resting on the knee before the beginning of the movement.Three movements of each limb are performed under visual guidance.
0 Normal
1 Oscillating movement without decomposition 2 Segmented movement in two phases and/or
moderate dysmetria in reaching the nose 3 Movement segmented in more than two
phases and/or considerable dysmetria in reaching the nose
4 Patient unable to reach the nose SCORE Right ...
SCORE Left...
K. Finger-to-nose test: the “intention” tremor is specifically looked for. Tremor appearing during the “ballistic” phase of the movement is assessed.
See previous task.
0 Normal
1 Simple swerve of the movement
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2 Moderate tremor with estimated amplitude
#10 cm
3 Amplitude of tremor between 10 cm and 40 cm
4 Amplitude of tremor$40 cm SCORE Right ...
SCORE Left...
L. Finger-finger test: the sitting patient is asked to maintain medially the twofingers pointing at each other for about 10 sec at a distance of about 1 cm, at the level of the thorax, under visual guidance.
Action tremor is specifically looked for.
0 Normal 1 Mild instability
2 Moderate oscillations offingers with estimated amplitude#10 cm
3 Oscillations of thefingers between 10 and 40 cm
4 Jerky movements$40 cm of amplitude SCORE Right ...
SCORE Left...
M. Pronation-supination alternating movements: the subject is sitting on a chair. Forearms are raised vertically, and alternative movements of the hands are performed. Each side is assessed separately.
0 Normal
1 Slightly irregular and slowed
2 Clearly irregular and slowed, with no sway of the elbow
3 Extremely irregular and slowed movement, with sway of the elbow
4 Movement completely disorganized or impossible
SCORE Right ...
SCORE Left...
N. Drawing of the Archimedes spiral on a pre-drawn pattern: subject comfortably settled in front of a table.The sheet of paper isfixed on the table. No timing requirement. Dominant hand examined.
0 Normal
1 Impairment and decomposition, the line quitting the pattern slightly, but without hypermetric swerve
2 Line completely out of the pattern with recrossings and/or hypermetric swerves 3 Major disturbance due to hypermetria and
decomposition
4 Drawing completely disorganized or impossible
SCORE ...
Speech assessment (total of scores O to P)
O. Fluency of speech: the patient is requested to repeat several times a standard sentence, for instance: “A mischievous spectacle in Czechoslovakia”
0 Normal
1 Mild modification offluency 2 Moderate modification offluency 3 Considerably slow and dysarthric speech 4 No speech
SCORE ...
P. Clarity of speech 0 Normal
1 Suggestion of slurring
2 Definite slurring, most words understandable 3 Severe slurring, speech not understandable 4 No speech
SCORE ...
Oculomotor deficits (total of scores Q to S)
Q. Gaze-evoked nystagmus: the subject is asked to look laterally at thefinger of the examiner: the movements assessed are mainly horizontal, but may be oblique, rotatory, or vertical.
0 Normal 1 Transient
2 Persistent but moderate 3 Persistent and severe SCORE ...
R. Abnormalities of the ocular pursuit: the subject is asked to follow the slow lateral movement performed by thefinger of the examiner
0 Normal
1 Slightly saccadic 2 Clearly saccadic
SCORE ...
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Chapter 4 – Clinical scales
S. Dysmetria of saccades: the indexfingers of the examiners are placed in each temporal visualfield of the patient, whose eyes are in the primary position.The patient is asked to look laterally at thefinger on the right and on the left.The average overshoot or undershoot of the two sides is estimated.
0 Absence of dysmetria
1 Bilateral clear overshoot or undershoot of the saccade
SCORE ...
The ICARS is a reliable scale satisfying accepted criteria for inter-rater reliability, test–retest reliabil- ity, and internal consistency (Schmitz-Hubsch et al., 2006a). Inter-rater correlation is very high for the total score, and high to very high for each component sub- score (Storey et al., 2004).The scale is sensitive to a range of ataxia severities from mild to severe. Some authors argue that the ICARS might show some redun- dancies of several items and that the different factors extracted by a factorial analysis do not coincide with the ICARS subscores, questioning its usefulness (see sectionComparison between scales).
The ICARS is also useful to extract and rate the severity of cerebellar signs in multiple system atrophy, although it is contaminated by parkinsonian features (Tison et al.,2002).