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CEREBELLAR DISORDERS

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					CEREBELLAR DISORDERS



                by
            PURUSHOTHAM
             Cerebellum anatomy
located in posterior cranial fossa
    Tentorium cerebelli (cerebrum)
     -
   4th ventricle (brain stem)

- communicate with other structure
via superior, middle, and inferior
cerebellar peduncle

- longitudinal division
Vermis, Paravermal Region,
Cerebellar Hemisphere

- transverse division
 Anterior Lobe
    ------------ primary fissure
 Posterior Lobe
                 postero-
    ------------ postero-lateral fissure
 Flocculonodular Lobe
Cerebellum anatomy
      Cerebellum                 Classifications


                            Classification by
                            Phylogenetic
                            Development
Anatomical Classification
   Anterior Lobe            Paleocerebllum
   Posterior Lobe           Neocerebellum
   Flocculonodular Lobe     Archicerebellum

                            Functional
                            Classification
                            Spino cerebellum
                            Cerebral cerebellum
                            Vestibulo cerebellum
    Cerebellum                      Function


  Maintenance of Equilibrium
   - balance, eye movement
  Coordination of movement and maintenance of posture
   - posture, gait
  Adjustment of Muscle Tone

 Role in motor control, Motor Leaning – Motor Skills

 Sequencing and timing of movement

 Control of rapid muscular activities ex: playing musical

instrument

  Cognitive Function
          cerebellum Syndromes
                 syndrome:
  Posterior lobe syndrome: Intension tremor
                         Dysmetria
                         Dysdiadochokinesia
                         Speech problems

                syndrome:
  Anterior lobe syndrome: Gait ataxia
Loss of coordination /Clumsy movements of lower limbs

                   lobe:
  Flocculonodular lobe: Truncal ataxia. standing on wide
  base of support, reeling from side to side
    Cerebellum             Internal Configurations


Cerebellar Cortex

    Molecular Layer
    Purkinje Cell Layer
    Granular Layer

Medullary Center

Deep Cerebellar Nuclei

      Fastigial Nuclei
      Globose Nucleus
      Emboliform Nucleus
      Dentate Nucleus
u




    Out put

              in put
Blood supply to the cerebellum
      Main Connections of the Vestibulocerebellum


Vestibular
 Organ                                     Floculonodular
                                               Lobe
              VESTIBULAR NUCLEUS             Vermis


    vestibulospinal tract

                  MLF                      FASTIGIAL
                                           NUCLEUS

                 lower motor neuron     ARCHICEREBELLUM

                      LMN
          Main Connections of the Paleocerebellum



         RED                                    NUCLEUS
                                             INTERPOSITUS
       NUCLEUS


rubrospinal
      tract                Inferior             ANTERIOR
                            Olivry                LOBE
                                               PARAVERMAL
                           Nucleus                ZONE



     lower motor neuron                     PALEOCEREBELLUM
     SPINAL CORD          spinocerebellar
                          tract
            Main Connections of the Neocerebellum



   CEREBRAL                                  DENTATE
                        THALAMUS
    CORTEX                                   NUCLEUS



pyramidal
    tract               Pontine              POSTERIOR
                                                LOBE
                        Nucleus              CEREBELLAR
                                             HEMISPHERE


  lower motor neuron                       NEOCEREBELLUM
       LMN
      Pyramidal Tract and Associated Circuits



                  upper motor neuron
                        UMN


                                           BASAL
Cerebellum
                                          GANGLIA
                pyramidal      tract

                  lower motor neuron
                        UMN
         Cerebellum and Automatic Motor Control


Motor Cortex

                                                 CEREBELLUM

                      Red Nucleus



          Reticular                 Vestibular
         Formation                   Nucleus




      Lower Motor Neuron (LMN)                     Proprioceptors
      Cerebellum                              Clinical Syndromes


                                 lobe):
Archicerebellar Lesion (Floc nod lobe): truncal ataxia
                             LOBE):
Paleocerebellar Lesion (ANT LOBE): gait disturbance
                           lobe):
Neocerebellar Lesion (post lobe): hypotonia, ataxia,
intentional tremor.
------------------------------+++++++------------------------------------------
------------------------------+++++++------------------------------------------
 Ataxia:
•Ataxia: incoordination of movement
    - decomposition of movement (dyssynergia)
                      past-
    - dysmetria ( past-pointing)
    - dysdiadochokinesia
    - rebound phenomenon
    - gait ataxia, truncal ataxia, titubation
•Intention Tremor
•Hypotonia
• Nystagmus
               PROGRESSIVE ATAXIA

The degenerative disorders manifested by progressive
ataxia are termed spinocerebellar degeneration.

Familial cerebellar degeneration of
childhood is

         Ataxia Telangiectasia
            (Louis- Bar syndrome)

     Is a primary immunodeficiency disorder
Familial spino cerebellar degeneration of adults:

Spinal form :   Friedreich’s Ataxia.

                Roussy-levy syndrome.

                Marie’s spastic ataxia.

Cerebellar form : Cortical      cerebeller degeneration
                   Dyssynergia cerebellaris myoclonia.
                   ( Ramsay Hunt syndrome)

                   Olivo ponto cerebellar degeneration.
  Friedreick’s ataxia

•Is a rare inherited disorder that affects the nervous system.

•Is an abnormality of the motor & sensory nerve conduction
mainly involving the spinal cord.

•The spinal cord is shrunken, especially in the thoracic
region.

•There is degeneration & gliosis of :
             •Posterior column, cortico-spinal tracts,

             •Ventral & dorsal spino cerebellar tracts.
   Sensory Ataxia                               Syndrome


Tabes Dorsalis
  - common variety of neurosyphilis

  - posterior colum and spinal posterior root lesion

  - loss of discriminative touch sensation and conscious
      proprioception and vibration below the level of lesion

  - loss of deep tendon reflex (DTR)
                          2. posterior
                             white column




Sensory ataxia (tabes dorsalis)
               Sensory Ataxia
  Is distinguished from cerebellar ataxia by the
presence of
  near normal coordination with eyes opened.

   Also it lacks the associated features of cerebellar
ataxia
   such as pendular deep tendon reflexes,
           Scanning dysarthia,
           nystagmus.
   Demonstrate pseudo athetosis & Romberg’s sign.
             Clinical features
Ataxia:
Ataxia: incoordination of movement
   - decomposition of movement (dyssynergia)
                  past-
   - dysmetria ( past-pointing)
   - dysdiadochokinesia
   - rebound phenomenon
   - gait ataxia, truncal ataxia, titubation

Intention Tremor
Hypotonia
 Nystagmus
Impaired balance
                           )
Dysarthria (Scanning speech)
Pendular knee jerk
    a   b   c
                Cerebellar
                  Ataxia

                Ataxic gait and
                position:
d                 Left cerebellar tumor

                a. Sways to the right in
                   standing position
                b. Steady on the
                  right leg
                c. Unsteady on the
                  left leg
                d. ataxic gait
Balance
Motor Skill




         Pablo Casals
  Posture
Gait – Ataxia
  Tremor
       Cerebellar
    Medulloblastoma
(flocculonodular lesion)
    Cerebellar tumors on vermis
     - Truncal Ataxia
     - Frequent Falling

    The child in this picture:
     - would not try to stand
       unsupported
     - would not let go of the bed rail
       if she was stood on the floor.
Investigations
DIFFERENT FORMS OF
      ATAXIA
           PROGRESSIVE ATAXIA

The degenerative disorders manifested by progressive
ataxia are termed spinocerebellar degeneration.

Familial cerebellar degeneration of childhood is

           Ataxia Telangiectasia

      ( Boder-Sedwick syndrome or Louis- Bar syndrome)

     Is a primary immunodeficiency disorder
                     Definition / Criteria

  Early onset progressive cerebellar ataxia.

   Oculo-cutaneous telangiectasia ( dilated blood vessels in
the
    eyes & skin.)

  Immunodeficiency mostly through IgA,IgG & Ig E levels.

  Hypersensitvity to ionising radiations.

  Increased incidence of malignancies primarily lymphoid.

  Raised alpha – fetoprotein levels.
   Familial spino cerebellar degeneration of adults :

Spinal form : Friedreich’s Ataxia.

              Roussy-levy syndrome.

              Marie’s spastic ataxia.

Cerebellar form : Cortical cerebeller degeneration of Holmes

                  Dyssynergia cerebellaris myoclonia.
                  ( Ramsay Hunt syndrome)

                  Olivo ponto cerebellar degeneration.
                Friedreick’s ataxia
Is a rare inherited disorder that affects the nervous system.

Is an abnormality of the motor & sensory nerve conduction
mainly involving the spinal cord.

The spinal cord is shrunken,especially in the thoracic region.

There is degeneration & gliosis of :

Posterior column,corticospinal tracts,

Ventral & dorsal spino cerebellar tracts.
Cerebellar form : Changes in cerebellum are less marked,

There is purkinje cell loss & atrophy of dentate nucleus.


Clinical presentation :

Onset in the first or second decade .

Progressive ataxia,dysarthia, nystagmus.

Loss of vibration & joint position sense.
                     Genetics
Freidreick’s ataxia is inherited autosomal recessive disorder

T is due to an abnormality in the gene located in the
chromosome 9 (frataxin mitochondrial protein)
             Sensory Ataxia
Sensory ataxia is both sign & symptom in neurological
disorders.

Is a form of in coordination.

Is distinguished from cerebellar ataxia by the presence of
near normal coordination with eyes opened.

Also it lacks the associated features of cerebellar ataxia
such as pendular deep tendon reflexes,scanning dysarthia,
nystagmus.

Demonstrate pseudo athetosis & Romberg’s sign.
Patient usually complains of loss of balance in the dark.

Sensory ataxia is present in sensory polyneuropathies,
conditions causing dysfunction of dorsal columns
such as Tabes dorsalis.
Movement disorders associated
           with
    Cerebellar lesions
Hypotonicity
Hypotonia is a typical symptom of cerebellar lesion.

Lack of cerebellum’s facilitatory input.

Ipsilateral if lesion confined to lateral cerebellum but
may be bilateral or contralateral to lesions in the
intermedaite area of the cerebellum.
Can be detected by:

  Palpation.

  The extremity drops against gravity.

  If the client is distracted the object may drop
  from his grasp.

  DTR may be subnormal or low usually pendular.
Asthenia
A lesion of the cerebellum can produce asthenia.

Muscle strength on the involved side reduces by 50%

Bremer theorized that asthenia is caused by loss of
cerebellar facilitation to the motor cortex, which
In turn could reduce the activity of spinal motor
neurons.

Future research is required to untangle the patho
physiology of asthenia & hypotonicity.
                 Ataxia


Is a umbrella term used to describe the lack of
coordination displayed by individuals with
cerebellar lesions.
              Trunk & Extremities
Disturbances of posture & balance.
Lesions of the vestibulo-cerebellum cause an
extreme instability of stance & posture.

Posture may be distorted by changes in
propioceptive loops that operate via cerebellum,

Dorsal cerebellar, ventral cerebellar, spino olivary

Deiter’s nucleus & fastigal nucleus

Decreased fusimotor activity.
Postural tremor may be evident by back & forth
oscillatory movements of the body while the
patients maintains a standing posture.

The freqeuncy of this oscillation is typically about
3 hz & both antagonistic muscles about a joint
participate.

When standing individuals have a tendency to
spread their feet apart & use their arms for
balance.
                    Dysmetria

Is a disturbance in the ability to judge the distance or
range of a movement ,

It may be manifested by an overestimation or an
underestimation of the required range needed to reach
the object or goal.

People with cerebellar damage may also display
intentional tremor, in which a hand oscillates back &
forth as they try to touch their nose or the heel
oscillates as they attempts to slide it down the opp shin.
This tremor has a frequency of 3 to 5 hz & is
typically enhanced during the termination of
goal directed movement.

Abnormal co-activation of the antagonists could
contribute to dysmetria.

This would delay in reversing any resistive movt,
producing an overshoot & very imprecise alternating
movt against resistance.
Disturbances of gait
• Staggering gait.

• Generally unsteady, irregular, deviated.

• Arm swing is typically lost.

• The cerebellum has been theorized to play a
  significant role in the generation of locomotion.

• Gait disruption can be result of errors in rate &
  absolute level of force of muscle contraction
Movement decomposition (Dyssynergia)

A client with a cerebellar lesion may perform a
movement in a distinct sequence of steps rather in
a one smooth pattern.

Dysfunction of the dentate nucleus has been
implicated in movement decomposition .

Asynergia is the loss of ability to associate muscles
together for complex movement pattern.
Dysdiadochokinesia
Is a impaired ability to perform rapidly alternating
movements.

Movts are irregular , with rapid loss of range &
rhythm especially as the speed is increased.

Dysdiadochokinesia is related to dysmetria in that
both result from the inappropiate timing of
muscle activity.
                Dysarthria

Scanning speech

Typically slow, slurred , hesistant with prolonged
syllables.

Inablity of muscles of the larynx to intiate or stop
contractions quickly or hypotonicity
                Nystagmus

Voluntary movements of the eyes is also affected
by cerebellar lesions.

A relatively common disturbance in the eye movt
is gaze evoked nystagmus.

Is believed to be linked to the cerebellum’s influence
on synergy & tone of the extra occular muscles.
   Rebound phenomenon


Was originally described by holmes.

Is the loss of check reflex.
Physiotherapy Assessment
         Preliminary considerations

Level of skill in each activity ( including amount of
assistance or assistive devices required).

The occurrence of irrelevant movements, oscillations,
swaying, unsteadiness.

Number of extremities involved.

Distribution of co-ordination impairment;
Proximal or distal
Situations or occurrences that alter ( increase or
decrease) coordination deficits.

Amount of time required to perform an activity.

Level of safety.
Testing protocol
         Gather equipment

Coordination assessment form

Pen or pencil to record data

Stopwatch

Mat or treatment table

Method of occluding vision
             Testing protocol

Are movts direct, precise,& easily reversed ?

Do mvts occur within a reasonable or normal
amount of time ?

Does increased speed of performance affect
quality of motor activity ?

Can appropriate motor adjustments made if
speed & direction are changed ?
Does occluding vision alter the quality of motor
activity ?

Is there involvement proximal or distal ?

One side of the body versus the other ?

Does patient fatigue rapidly ?
         Recording test results
4= Normal performance is demonstrated.

3= Mvt accomplished with slight difficulty.

2= Moderate difficulty is demonstrated,
arrhythmic, performance deteriorates with
speed.

1= Severe difficulty.

0= Patient is unable to accomplish activity.
                   Hypotonicity
                           Reduced firmness
Muscle palpation

                           Pendular
DTR

                           All the fingers are flexed
Flex one finger only

                           Slack, asymmetrical
Resting posture

Hold object while
                           Drops objects when
conversing
                           distracted
                 Asthenia

Maintain arms in 90    Arms tire quickly
degree flexion

Max resisted muscle    Weaker contractions
contraction



ADL activities         Tire easily
    Balance & postural control

Hold limb against pull    Postural tremor
of gravity

Pertubations in sitting   Loses balance easily
and standing



Stand on one foot         Loses balance easily
or walk backwards
         Standing posture

Feet apart

Trunk flexed slightly

Needs to hold for stability

Postural tremor of legs
               Dysmetria

Flex arms to             Not able to resume 90
90,quickly elevate       degree without
over head then return   initial error
to 90
                        Intentional tremor
Slide heel down shin    undershoots or
slowly
                        overshoots

                        Intentional tremor
Peg hole
           Gait disturbance

March in one place      Unable to follow
                        rhythm


Walk on heels or toes   Loses balance &
                        rhythm
Walk clockwise &
counter-clockwise
counter-                Stumble in one
                        direction
       Typical gait pattern

Slow

Stumbles easily

Not rhythmical

Irregular Step length &height
        Dysdiadochokinesia

Tap hand on knee   Rapidly loses rhythm



Walk as fast as    Gait becomes
possible           impaired



ADL                Unable to brush teeth,
                   stir food
    Movement decomposition

Touch heel to      Mvt broken up into
opposite knee      separate phases



Typical movement   Activity appears as if
                   in slow motion
Non equilibrium coordination test
    Finger to nose

    Finger to therapist finger

    Alternate nose to finger

    Pronation / supination

    Rebound test

    Pointing & past pointing

    Heel on shin

    Drawing a circle
Equilibrium coordination test
    Standing.

    Standing with feet together.

    Standing in tandem walking position.

    Standing on one foot.

    Walk sideways, backwards, cross stepping.

    March in place.
              Romberg’s sign


Neurological test to assess dorsal column.

Is positive if & only if,

   The patient can stand with eyes open.


   The patient falls with eyes closed.
Rehabilitation
       Physiotherapy goals


Postural stability.

Functional gait.

Accuracy of limb movement.
      Head & trunk control

Needs to be assisted sequentially to each
level of independency.

Sitting can be achieved only when there is
good head & trunk control.

Standing only when sitting balance is
achieved.
       Head & trunk control

Work on head control.

Prone posturing on wedge.

Facilitation.

Biofeedback.
          Sitting balance
 Joint approximation techniques at
proximal joints.

Rhythmic intiation & stabilization.

Progressive challenges in sitting.

Weight shifting.
       Preparing for ambulation
Hip stability ( kneeling, crawling).

Quadriped position.

Activities in parallel bar.

Tremors can be reduced by ankle
weights.
      Preparing for ambulation

 Rhythmic stabilization applied to trunk
rotation.

Biofeedback from Force platform.

 Activities can be practiced in rhythm
with music to promote skill &
progression.
             Ambulation
 Feedback about step length, body
rotation, accessory mvt.

Use of ambulatory aid.
                 Dysmetria
Use of PNF patterns .

Frenkel’s exercises.

Slow progression.

Tie weights to the extremity.

EMG Biofeedback.
   DR. PURUSHOTTAM
   ASST. PROFESSOR



  SRINIVAS COLLEGE OF
PHYSIOTHERAPY, MANGALORE