ATAXIA
By
Dr. Heba A. Metwally

Anatomy and physiology of cerebellum

Cerebellar disorders (Ataxia): defintion,
clinical features, types.

Problems of ataxic patients

Physical management of ataxia
A)Assessment
B) treatment
ANATOMY AND PHYSIOLOGY OF CEREBELLUM
Anatomy:
Cerebellum lies behind the brainstem and occupies
most of the posterior cranial fossa.
 It is attached to the brain stem by 3 pairs of tracts
called the cerebellar peduncles which connect the
cerebellum with other centers in the CNS.
 It is composed of
 Gray matter → forming the Cerebellar cortex, Deep
cerebellar nuclei (Dentate, Interposed and Fastigial
nuclei).
 White matter → formed of fibers entering and leaving
the cerebellum through the cerebellar peduncles

Dentate nucleus
Interposed nucleus
Fastigial nucleus
ANATOMY AND PHYSIOLOGY
OF CEREBELLUM
♦ Anatomy
 It is divided (by 2 fissures; 1ry and posterolateral fissure) into 3
prominent anatomical lobes:
A. The anterior lobe.
B. The posterior lobe.
C. The flocculonodular lobe.
 The anterior and posterior lobes are divided into longitudinal
zones;
 a) Vermal zone → occupies the vermis.
 b) Intermediate (or paravermal) zone → lying on each side of
the vermis, occupying the medial regions of the cerebellar
hemispheres.
 c) Lateral zone of the cerebellar hemisphere → lying just
lateral to the intermediate zone.
ANATOMY AND PHYSIOLOGY OF CEREBELLUM
 It
1.
2.
3.
is divided into 3 major functional divisions;
Vestibulocerebellum→ composed of the
"flocculonodular lobe“→ connected to vestibular
apparatus.
Spinocerebellum → composed of the vermis and
paravermal zone→ connected to spinal cord.
Cerebrocerebellum→ composed of lateral zones
of the cerebellar hemispheres→ connected to
cerebral hemispheres.
FUNCTIONS
OF THE
CEREBELLUM
1.
Regulation of Equilibrium.
2.
Maintenance of tone.
3.
Regulation
(or
Coordination)
Voluntary Movements.
4.
Motor learning.
of
FUNCTIONS
OF THE
CEREBELLUM
1. Regulation of Equilibrium.
Through connections with vestibular apparatus, cerebellum
helps to maintain equilibrium during the change in head position,
and during exposure to acceleration or active movements of the body
Lesion leads to disturbances in equilibrium during standing
and walking
2. Maintenance of tone.
Through connections with spinal cord, cerebellum regulates the
tone and contraction of the axial and proximal limb ms.
Lesion leads to hypotonia.
FUNCTIONS
OF THE
CEREBELLUM
3. Coordination of Voluntary Movements.
Through connections with cerebral hemispheres,
cerebellum coordinate voluntary movements
Defintion of coordination: it is the ability to use the
right muscle at right time with proper intensity to reach
certain goal.
Coordination of movements means one's ability to
proceed smoothly and precisely from one movement to
the next in proper succession.
FUNCTIONS
OF THE
CEREBELLUM
3. Coordination of Voluntary Movements:
 The
cerebellar role in coordination of movements is
carried out by a No. of mechanisms, including:a) Comparator and Error- Correction Mechanism.
b) Damping Mechanism.
c) Planning the Sequence and Timing of Movements
FUNCTIONS
OF THE
CEREBELLUM
3. Coordination of Voluntary Movements:
a)




Comparator and Error- Correction Mechanism.
When the motor areas of the CC send motor commands to ms
for performance of a voluntary movement, the cerebellum
receives immediately an "efference copy" of the intended
motor command
As the movement proceeds, the cerebellum receives
proprioceptive signals about the actual motor performance.
Cerebellum acts as a "comparator" that compares the motor
intentions of the higher centers with the actual performance
of the involved ms.
When there is any "error" in performance or "deviation" from
the original plan of the intended voluntary motor act, then the
cerebellums send 'corrective signals" back to the motor areas of
the CC →ms.
Corrective signals
Plan of motor act•
Actual performance •
FUNCTIONS
OF THE
CEREBELLUM
3. Coordination of Voluntary Movements:
b) Damping Mechanism.
 All movements of the body tend to overshoot
due to momentum. The cerebellum sends
braking signals to stop the movement at
intended point, thereby preventing the
overshoot.
 If the cerebellum is damaged, the cerebral
cortex will recognize the overshooting only
after it occurs and corrects it, this leads to
oscillation of the limb around the intended
point i.e. intention kinetic tremor.
FUNCTIONS
OF THE
CEREBELLUM
3. Coordination of Voluntary Movements:
c) Planning the Sequence and Timing of Movements:
a)
A)
Planning:
cerebellum
receives
signal
from
the
cortical
association areas before the start of movement. it then provides the
plan of the next movement without being involved at all at the
present movement.

B) Timing ( predictive): cerebellum provides perfect timing of
voluntary movements. This is established by computing (calculating)
the appropriate timing for the "onset" and "termination" of
contraction of each of the ms involved in the performance of the
successive movements during voluntary motor acts → assures the
smooth progression of the whole movement.
FUNCTIONS
OF THE
CEREBELLUM
4. Motor learning:
 When
a person first performs a complex motor act,
the degree of cerebellar adjustment of movements is
almost always inaccurate, then cerebellar neuronal
circuits learn to make more accurate movement the
next time.
 Thus, after the motor act has been repeated many
times (motor training), the successive steps of the
motor act become gradually more precise.
 Once the cerebellum has perfectly learned its role in
different patterns of movements, it establishes a
specific "stored program" for each of the learned
movements (feed-forward)
Feed-forward: means that cerebellum programs or
models voluntary movement skills based on memory of
pervious sensory input and motor output.
 These
movements include writing, typing, talking,
running, and many other athletic and professional
motor skills.
 These movements occur so rapidly that it is almost
impossible to depend for their control on the sensory
feed-back information from the periphery, because the
movement would be over before such information
reaches the cerebellum and the cerebral cortex.
 These movements are referred to as "ballistic"
movements (ballistic is a word meaning "thrown"),
because once the movement goes on there is no way to
modify its present course by any sensory feed-back
control mechanism.
CEREBELLAR DISORDERS (ATAXIA):
Definition:
Ataxia is incoordination of voluntary motor activity with or
without dis-equilibriation in the absence of motor weakness.


Cerebellar syndromes (Main clinical features):
a) Archicerebellum= vestibulocerebellum syndrome:



It is manifested by:1) Swaying during standing, with a tendency to fall down.
2) Unsteady (staggering) gait→ wide-based in order to
provide better equilibrium during walking
CEREBELLAR DISORDERS (ATAXIA):

Cerebellar syndromes (Main clinical features):
b) Paleocerebellum=spinocerebellum syndrome:
It is manifested by: Hypotonia and hyporeflexia that occur also in both
Archicerebellar and Neocerebellar syndromes

CEREBELLAR DISORDERS (ATAXIA):

Cerebellar syndromes (Main clinical features):
c) Neocerebellum= cerebro cerebellum syndrome:
It is manifested by: Hypotonia and hyporeflexia
 Asthenia
 Incoordination;
- 1) Dysmetria→ inability to judge (errors) in the range and
direction of the movement (hypometria or hypermetria)
- 2) Intention Tremors (Kinetic Tremors): They appear
when the patient performs a voluntary motor act, not seen
when the ms are at rest.
N.B: patients has head nodding, trunk titubation and
intention kinetic tremors of extremities.

CEREBELLAR DISORDERS (ATAXIA):





3) Decomposition of Complex Movements: The motor act is
carried out as several fragmented steps rather than a smoothly
progressing movement.
For instance, in reaching for an object by the hand, the cerebellar
patient may first move the shoulder joint, then the elbow,
followed by the wrist and fingers → simulate movements of a
"robot".
4) Rebound Phenomenon
The cerebellar patient is unable to stop the ongoing movement
rapidly due to failure of the damping functions of the cerebellum.
This can be observed in what is called "rebound phenomenon".
When there is a flexion of the forearm against resistance
(provided by the examiner's hand), the cerebellar patient cannot
stop the resultant inward movement of his limb in due time
following its release, and the forearm flexes forcibly and may
strike his body with considerable violence.
CEREBELLAR DISORDERS (ATAXIA):
5) Dysdiadochokinesia
 • Dysdiadochokinesia → inability of the patient to
perform rapid alternating opposite movements e.g.
rapid repetitive pronation and supination of forearm.
 The movements are slow and irregular.
 • It results from failure to adjust precisely the proper
timing for the onset and termination of the successive
alternating contractions of the opposing ms groups.
 6) Nystagmus
 Nystagmus of cerebellar disorders is a tremor of the
eye balls as a result of "dysmetria" of the "saccadic
movements" of the eyes.

CEREBELLAR DISORDERS (ATAXIA):









7) Dysarthria:
Staccato speech →slow, explosive, interruptive speech. Or
scanning speech →slow and decomposed speech.
Decomposition of words is due to failure to adjust the
precise timing of contraction of the different ms of speech.
8) Unsteady Gait
The gait is unsteady and broad-based due to dysmetria and
kinetic tremors of the lower limb ms.
Unilateral Mild lesion→ deviation toward same side of
lesion
Bilateral mild lesion → zigzag gait.
Unilateral sever lesion→ wide base gait
Bilateral sever lesion → drunken gait.
CEREBELLAR DISORDERS (ATAXIA):

Types:
Cerebellar ataxia
Sensory ataxia
Vestibular ataxia
Combined ataxia
CEREBELLAR ATAXIA
CEREBELLAR ATAXIA
Friedreich ataxia
Heridofamilial, occurs 1st decade of life.
 Pathologically there is degeneration in
Archicerebellum mainly------- Ataxia.
Pyramidal tracts-------- +ve Babiniski sign
Posterior column-----lost deep sensation, diminshed
reflexes
Peripheral neuropathy----stock and glove
hypoesthesia
Other features :skeletal deformities e.g. pes cavus,
scoliosis and ♥cardiomyopathy.

SENSORY

ATAXIA
Definition: It is ataxia due to loss of the proprioceptive
(deep) sensations, at any point in their pathway (see fig. 9).

Causes:
Peripheral nerve: peripheral neuropathy specially diabetic,
alcoholic and nutritional.
Posterior root: tabes dorsalis.
Posterior column: subacute combined degeneration of the
cord.
Medial lemniscus: brain stem lesions.
Thalamus: thalamic syndrome.
Cortical sensory area: parietal lobe lesions.
SENSORY
ATAXIA
Clinical picture:
Kinetic tremors appear only on closure of the eyes.
Rhomberg's test: when the patient stands with his
feet close together & his eyes closed, his body sways &
he may fall if not supported.
Stamping gait: heavy strike of the ground on walking
due to lost deep sensation.
Deep sensory loss.
Hypotonia
Hyporeflexia

VESTIBULAR ATAXIA

Definition: It is ataxia due to lesions of the
vestibular division of the vestibulocochlear nerve .

Causes:
Meniere's disease.
Labyrinthitis.
Acoustic neuroma.

Clinical picture:
Vertigo, tinnitus, deafness & vestibular nystagmus.
Problems of movement regulation expressed as error
in rate, range, direction and force.
 Balance reactions are inappropriate and slow to be
initiate . Difficulty in adapting posture to changing

condition.
Lack of the normal regulation and graduation of
muscle contraction necessary for all movement and
posture  excess of motion
 Instability around shoulder interfere with:
a) control of the arm
b) manipulation of object at a distance from him.
 Instability around pelvis interfere with the control of
the pelvis of the extended leg.


Difficulty in regulating small ranges of mov + intention tremor lead to problems with
manipulation activities

Poor visual fixation and eye hand contact due to ataxic arm movement, nystagmus and
voluntary restriction of head movement

Orofascial dysfunction

Poor posture

Subnormal ADL

Secondary problems as respiratory, circulatory and deformity may occur in sever cases.

Gait problems
hypermetria  manifest itself by raising the feet to an unnecessary high level above the
ground.
decomposition  result in lag of the trunk to be moved forward with the movement of
the leg with a tendency to fall backward.
MANAGEMENT OF ATAXIA
 Assessment:
Some important points must be considered as:
 Assessment and evaluation of both sides of the body must
be done even if unilateral lesion of cerebellum has been
diagnosed.
 Assessment and evaluation of the patient must be done in
quite place to prevent distraction, considering age of the
patient, and his psychological status to gain full
cooperation from him.
 Assessment and evaluation of functional activities must
include:
- Assistance needed
- Time to complete activity
- Level of effort involved
- Potential hazards
MANAGEMENT OF ATAXIA
 Assessment:
Some important points must be considered as:
 Assessment and evaluation of posture and ROM are
very important because the possibility of presence of
congenital deformities.
 Assessment
and
evaluation
of
coordination,
considering the components of movements ( response
orientation, control, speed,…etc).
 Evaluation of gait, ask the patient firstly to walk
slowly then change directions with different speeds.
 Patient’s progress in ambulation can be determined
by the numbers they loose their balance in treatment
session, frequency of a specific errors, the distance
ambulated or the level of assistance needed.
Assessment of ataxic patients
- Motor assessment including muscle tone and muscle
test, reflexes and ROM.
- Sensory assessment including superficial and deep
sensation
- Orofacial function assessment including facial
expression, lip & jaw closure….etc.
- Coordination of respiration with swallowing and
speech.
Gait assessment
- International Cooperative Ataxia Rating Scale
(Evaluating truncal and extremity ataxia, gait ataxia,
nystagmus and talking)
Assessment of ataxic patients
- Coordination assessment (the most important
item) including equilibrium and non equilibrium
subtypes.
- Equilibrum coordination tests stastic and dynamic
balance.
- Non equilibrum coordination tests focus on
assessment of movement capabilities in four main
areas:
1- Alternate or reciprocal motion.
2- Movement composition, or synergy.
3- Movement accuracy.
4- Fixation, or limb holding.
Movement Capabilities The non-equilibrium coordination
examination focuses on movement capabilities in several
main areas:
• Alternate or reciprocal motion, which is the ability
to reverse movement between opposing muscle groups
• Movement composition, or synergy, which involves
movement control achieved by muscle groups acting
together
• Movement accuracy, which is the ability to gauge or
judge distance and speed of voluntary movement
• Fixation or limb holding, which addresses the
ability to hold the position of an individual limb or limb
segment
ASSESSMENT OF NON EQUILIBRIUM COORDINATION
It includes specific tests
In upper limb:
Finger to nose test
Finger to finger test
Finger to Doctor finger test
Adiadokokinesia
Rebound phenomena
In lower limb:
Heel to knee test
Walking along a straight line (tandom)
Romberg test
ASSESSMENT OF NON EQUILIBRIUM COORDINATION
ASSESSMENT OF NON EQUILIBRIUM
COORDINATION
THE GOALS OF RESTORATIVE PHYSICAL TREATMENT CAN
BE BRIEFLY DESCRIBED AS:








Long term goal: - To make the patient functional as much
as possible with maximum safety and less energy cost.
Short term goals:1. To improve the background of movement by improving
proximal control, stability, and postural reactions.
2. To regulate the interplay between two muscle groups.
3. To reduce tremor.
4. To improve visual fixation and eye hand contact.
5. To improve orofacial problems.
6. To improve gait problems.
TREATMENT:
1-Methods to improve proximal instability :
 Approximation
 Rhythmic Stabilization: - It is simultaneous isometric
contraction of agonist and antagonist.
 Alternative isometric technique. It is an isometric
contracrion of antagonist followed by isometric
contraction of agonist.
 Tonic holding
 Weight bearing position as quadruped position and
maintain it for 20 minutes.
TREATMENT:
2- Methods to improve coordination :
A- PNF techniques
 Slow-reversal and Slow-reversal hold technique.
 Compined pattern of PNF (bilateral symmetrical,
bilateral asymmetrical, reciprocal same diagonal and
reciprocal opposite diagonal).
B. Frenkel's ex for lower limbs and coordinated
exercises for upper limbs
TREATMENT:
2-Methods to improve coordination :
C. Frenkel's ex: - It is a series of coordinated exercise
designed to improve coordination of lower limb with
specific graduation to compensate proprioceptive loss by
other intact neural sense.
Principles
- It should be done slowly
-The patient must watch movement carefully so put
pillow under the head if the patient is supine lying.
- When he control one activity then proceed the next
one
- - Command should be sharp.
TREATMENT:
Methods to improve coordination :
1. Frenkel's ex:
Graduations
1. Fast then slow
2. Big joint then small joint
3. One joint then more than one joint
4. One direction then more than one direction
5. Unilateral then bilateral
6 Symmetrical then asymmetrical
7. Continuous then interrupted
8. on the bed then off the bed
9. Wide BOS then narrow BOS (Supine then sitting
then standing)
COORDINATION TRAINING INCLUDE:
Perception:
to tell whether or not performance is occuring as
desired through proprioceptive pathways and reinforced by visual
and tactile perception.
Precision:
breaking down activity to units which are simple so
that they can be practiced more precisely.
Perceptual practice: repetition of activity at frequentaly
intervals. Millions of time.
Peak
performance: the patient practices the movement below
the peak performance which is determined according to complexity,
muscular effort and repetion in order to avoid fatigue
Progression:
revision of peak performance as improvement
occur and transition of exercise s into functional goal.
TREATMENT:
3. Methods to decrease The Tremor of limbs
 Tonic holding
 Alternative isometric ex.
 Slow reversal hold with hold at the end and in
between
 It can be reduced by ankle and wrist weights (Velcro
cuffs) (1-2LB) for wrist (2-3LB) for ankle or weighted
belt
 4. Methods to manage athenia: Graduated Resistive exercises to antigravity muscles.
 Endurance Ex
TREATMENT:
5. Methods to improve balance:
 Balance can improved in antigravity position
(sitting, standing) in normal base of support
 - Postural stability is improved by using antigravity
position in the developmental sequence
 - Tai Chi and yoga
 - Plyometric ex’s
TREATMENT:
6. Methods to manage gait (gait training):
Preparation for ambulation
1. This starts from sitting or prone to reach a quadruped position,
then advances to kneeling and then applies crawling
2. When standing from sitting, patient slides forward in the chair
and bends his trunk to put COG over his feet .The trunk and legs
should be extended only after gaining balance on the feet.
3. Standing activities should be started in the parallel bars.
4. Standing balance exercises.
5. Approximation through shoulders and hips.
6. Tremor can be reduced by ankle weight or weighted belt.
7. Rhythmic Stabilization for trunk rotation.
8. Maintain Standing without pulling on bars.
9. Once standing is stable, alternate lifting of feet is practiced.
SPECIFIC
INTERVENTIONS FOR BALANCE AND GAIT
I. Video-game based coordinative training
 Intensive coordination training using whole-body
controlled videogames can be an effective and
motivational therapy for children with progressive
ataxia.
 Supervision from a physiotherapist is essential to
ensure the correct movements are being performed
and for safety.
SPECIFIC
INTERVENTIONS FOR BALANCE AND GAIT
II. Treadmill training
 Treadmill training can be an effective intervention
for people with ataxia due to brain injury.
 Intensity and duration of training seem to be
significant factors. Consistent intensive training over
many months combined with over-ground training
may be required. This intervention has not been
tested in people with progressive ataxias. The
training programme consisted of three commercially
available Microsoft Xbox Kinect videogames
7- Methods to manage vertigo:
- Vestibular habituation exercises
- Cawthorne and Cooksey exercises
N.B.:

Cold application, vibration and strong resistance
have adverse effects on the ataxic patients.

crutches or canes may be used but require
reciprocal movement of arms and legs with
appropriate timing and placement.