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Cerebral Palsy
A motor function disorder caused by a permanent, nonprogressive brain defect or lesion present at birth or shortly thereafter
Cerebral Palsy
Describe the gross anatomy of the brain
Describe the functions of the lobes of the cerebral cortex, the pre‑ and post‑central gyrus
Describe the function of the hindbrain, midbrain, forebrain and brain stem
Describe the function of the basal ganglia
Describe the role of the motor cortex, basal ganglia and cerebellum in movement
Describe the function organisation of the basal ganglia and the communication pathways with the thalamus and cerebral cortex
Relate the motor and sensory homunculus to motor control and sensory receptor density and loss of function due to brain lesions
Name the cranial nerves and describe their functions
Compare the anatomical location and functions of the parasympathetic and sympathetic nervous systems
Compare Spastic cerebral palsy, Athetoid cerebral palsy and Ataxic cerebral palsy
Describe the role of the muscle spindle in determining posture
Cerebral Palsy
Types
Causes
Clinical Features
Associated Disorders
Motor Control
Types
4 Major Groups:
70% Spastic:
Motor Cortex, increased muscle rigidity and tone.
10% Athetoid or Dyskinetic:
Basal Nuclei, slow writhing, involuntary movements,
sometimes distal, jerky movement.
10% Ataxic:
Cerebellum, disturbance of balance, muscle coordination.
Interior tremor, hypotonia.
10% Mixed:
spastic/athetosis or ataxic/athetosis
25% Convulsions:
Causes
Inherited (5 -10%)
Prematurity / Maternal infection
Low birth weight
Anoxia
Perinatal trauma
Excessive neonatal jaundice
Childhood diseases
Trauma
Clinical Features
Persistence of primitive reflexes (>12mo)
Altered tone
Developmental delay in reaching milestones
Feeding problems
Visual perceptual difficulties
Hearing
Speech disturbances
Visual
Strabismus:
An abnormal ocular condition in which the visual axes of the eyes
are not directed at the same point
Myopia
A condition of nearsightedness caused by the elongation of the
eyeball or by an error in refraction so that parallel rays are focused
in front of the retina.
Nystagmus
Involuntary, rhythmic movements of the eyes.
The oscillations may be horizontal,, vertical, rotary, or mixed.
Agnosia
Total or partial loss of the ability to recognize familiar objects or
persons through sensory stimuli as a result of organic brain
damage.
Hearing
auditory agnosia
Speech
don’t develop correct feeding patterns
Associated Disorders
Hyperkinesis (attention deficit disorder)
Mental retardation
Epilepsy
Motor Control
3 levels of command have been recognised
Segmental
Projection
Programs/instruction
Segmental level
resides in each single segment of the spinal cord
Central Pattern Generators (CPGs) control the pattern of locomotion
Projection level
controls the spinal cord
two major pathways
pyramidal
extrapyramidal
Pyramidal pathway
Corticospinal tract
Corticobulbar tract
neurons of the primary motor cortex
large pyramidal tracts
collaterals to brain stem nuclei and cerebellum
activate voluntary muscles
largely excitatory
Cranial Nerves
I Olfactory
II Optic
III Oculomotor
IV Trochlear
V Trigeminal
VI Abducens
VII Facial
VIII Vestibulocochlear
IX Glossopharyngeal
X Vagus
XI Spinal Accessory
XII Hypoglossal
Extrapyramidal pathway
Reticular - standing
Vestibular - balance
Red nuclei - controls flexors
Superior collicili - mediate head movements in response
to vision and sound
set patterns of day to day activity
assumed these control CPGs
A tip
After severe damage to the Pyramidal system, movements become crude and speech slurred
Programs/Instructions level
Two major components
Cerebellum
Basal nuclei
Cerebellum
key centre, contains files for motor routines
ultimate target for ascending information
also receives information from collaterals and various brain stem nuclei
lacks direct connection to spinal cord
Cerebellum: appearance
Basal ganglia
Also known as Cerebral Nuclei or Basal Nuclei
Collection of nuclei in White matter of Cerebral Cortex
Contains caudate nucleus, putamen, globus pallidus
Communicates with Motor Cortex via the Thalamus
Basal ganglia
Function is often described in terms of “Brake Hypothesis”
To sit still, need to put the brakes on all movements except reflexes that maintain upright posture
To move, you must apply a brake to some postural reflexes, and release the brake on voluntary movement
Basal ganglia
Deficits fall into 2 categories: the presence of unwanted movements (brakes not applied when you want them)
OR
Absence or Difficulty with Intended movements (Brakes applied when you don’t want them)
Basal Nuclei
cross roads of many afferent and efferent pathways
receive input from primary and association areas
send output via thalamus to cerebral cortex
influence flow of motor information in extrapyramidal pathways
Motor areas of brain
Cerebrum
Pyramidal tracts
Basal ganglia (cerebral nuclei)
Brain stem nuclei
Extrapyramidal tracts
Cerebrum
Primary motor cortex present in precentral gyrus
Primary motor cortex plans motor activity
Motor cortex sends impulse for initiation of voluntary motor activity.
Neurons of pyramidal tract originate here and carry impulses to skeletal muscle.
Pyramidal tracts
Descending motor neuron tracts
(white matter in spinal cord),
which carry voluntary motor commands from cortex to skeletal muscle.
Tracts pass through brain stem and cross over (decussate) in brain stem.
Basal ganglia (cerebral nuclei)
Areas of grey matter in the brain that lie in each hemisphere beneath the lateral ventricle.
These control coordination of learned motor patterns and the muscle tone required for those movements.
Caudate nucleus. Coordination of motor activity (walking).
Lentiform nucleus.
Putamen. Coordination of moter activi9ty (walking).
Globus pallidis. Control muscle tone.
Brain stem nuclei
Brain stem nuclei more areas of grey matter that control muscle tone for posture and equilibrium.
Reticular formation processing control centre
Vestibular nucleus equilibrium / balance
Red nucleus muscle tone / posture
Tectum involuntary motor responses
Extrapyramidal tracts (white matter)
Descending motor neurons carrying unconscious motor commands from the cerebral nuclei and brainstem nuclei.
The cerebellum coordinates these motor commands, but no tract directly carries information from cer4ebellum, instead, the information comes through nuclei.