Cerebral Palsy - Paediatric Neurology

Cerebral Palsy

·        = A persistent disorder of posture or movement caused by a non-progressive, non-hereditary lesion of the immature brain, acquired either in utero or later at a time of rapid development of the CNS (up to several years after birth)

·        May be accompanied by other impairments, eg retardation, vision defects or epilepsy 

·        Though lesion is static, the clinical features may develop for several years as brain function matures (may give appearance of being progressive – clinical signs have to wait until that part of the brain    „kicks in‟)

·        Incidence:

o  Stable at about 2/1000.

o  80/1000 for very preterm babies

·        Stages of brain development:

o  Up to 20 weeks ® major brain malformations:

§  Lissencephaly (brain without cortex)

§  Microgyria: lots of little indentations

§  Migration defects: islands of grey matter in the middle of white matter 

o  26 – 32 weeks: neurons climb glial fibrils: intense growth – prone to ischaemia. If born then, prone to germinal matrix bleeds. But ischaemia more important ® Periventricular Leukomalacia (PVL) 

o  Myelination starts at about 30 weeks, but most is after birth. Damage only becomes obvious as myelination complete (conscious control of arm at 4 – 5 months, leg at 9 months) 

·        Causes:

o  Anything that damages neurons: ischaemia, hypoglycaemia, infection, trauma, toxins 

o  Only 10-30% attributed to “intrapartum asphyxia”. Normal PO2 in utero is 15 – 25 mmHg Þ well adjusted to hypoxia 

o  For many it‟s due to an unknown earlier adverse event

o  Significant proportion preterm (43%)

o  Intrauterine Growth Retardation ® ­risk by 5 times

·        Exam findings:

o  Hyperactive reflexes

o  Abnormal movements of chorea, athetosis, dystonia

o  Abnormal absence or persistence of infantile reflexes

·        Differential:

o  Metabolic disorder

o  CNS degenerative diseases

o  Cerebellar dysgenesis or spinocerebella degeneration

Classification

·        Hemiplegia:

o  0.79/1000

o  Congential: 

§  Spastic paralysis of arm and leg on same side. Arm usually weaker than the leg. Distal parts worse than proximal. Growth of affected parts reduced

§  Face not involved

§  Epilepsy common – correlates with degree of mental retardation (but IQ often normal) 

§  Mechanism: vascular (ie stroke in utero). If preterm, usually periventricular rather than cortical and leg weaker than arm

o  Acquired:

§  Following infection, trauma, CVA, status epilepticus, etc

§  Most in first 3 years of life

§  Flaccid with facial involvement, spastic later

·        Diplegia:

o  0.9/1000

o  Spastic:

§  Problem in preterm 28 – 32 weeks 

§  Follow bilateral periventricular injury, especially with hydrocephalus complicating, or injury to basal ganglia or parasagital cortex

§  Stiff lower limbs (may be floppy as neonates): flexion of hips and knees, scissoring (internal rotation and adduction), weak trunk and eventual contractures. May dislocate hips

§  Upper limbs variably affected (if worse then more global)

§  Hyperreflexia and spasticity with variable wasting

§  Epilepsy uncommon, intellect may be retained (69%).  Head growth mirrors intellect

·        Quadriplegia:

o   Global cerebral insult: massive haemorrhage, shock, obstructed umbilical chord

o   Upper limbs often worse than lower, generalised spasticity and wasting.

o   Severe mental retardation, cranial nerve palsies, aspiration, etc

·        Athetoid: 

o   Extrapyramidal injury, especially perinatal insults (including kernicterus – unconjugated hyperbilirubinaemia) 

o   Appears after 5 months: involuntary movements and posturing, poor trunk control, hypotonia or normal, normal reflexes

o   Impaired speech, drooling, facial grimacing, often deaf (especially high tone)

o   IQ often normal but difficulties communicating.  Epilepsy in 25%

·        Ataxic:

o   Cerebellar symptoms predominate

o   Cerebellum abnormal on imagining

o   Presents at 1 – 2 years, but floppy and docile from the start

o   Ataxia, intention tremor, late walking, high tone deafness, normal IQ in 50%

o   Can be familial disease

·        Management:

o   Team approach: physio, OT, orthopaedic surgeon, etc

o   Prevent contractures and encourage normal developmental stages

o   Treat epilepsy

o   Rule out deafness, check special senses

o   Encourage communication

o   Prevent malnutrition

o   Encourage mobility and upright posture (frees up hands for „learning‟ activities)

o   Support for child and family

o   Manage constipation, incontinence