cerebral palsy

cerebral palsy , disability caused by brain damage before or during birth or in the first years, resulting in a loss of voluntary muscular control and coordination. Although the exact cause is unknown, apparent predisposing factors include disease (e.g., rubella , genital herpes simplex ), very low infant birthweight (less than 3.3 lb [1.5 kg]), and injury or physical abuse. Maternal smoking, alcohol consumption, and ingestion of certain drugs can also contribute. Most cases are associated with prenatal problems; about 10% of the cases are thought to be due to oxygen deficiency during the birth process. The severity of the affliction is dependent on the extent of the brain damage. Those with mild cases may have only a few affected muscles, while severe cases can result in total loss of coordination or paralysis.

There are many different forms of the disability, each caused by damage to a different area of the brain. The spastic type, accounting for over half of the cases, results from damage to the motor areas of the cerebral cortex and causes the affected muscles to be contracted and overresponsive to stimuli. Athetoid cerebral palsy, caused by damage to the basal ganglia, results in continual, involuntary writhing movements. Choreic cerebral palsy is characterized by jerking, flailing movements. Ataxic cerebral palsy, involving the cerebellum, causes either an impaired sense of balance or a lack of coordinated movements. In addition to these types, which may occur singly or together, emotional, visual, and hearing impairments and convulsive seizures may be present. Some of those affected have a degree of mental retardation, but in many the intellect is unimpaired.

There is no cure for the disorder. Treatment usually includes physical, occupational, and speech therapy, and sometimes includes biofeedback and muscle relaxants. Sometimes appliances such as braces and surgery are helpful. Measures that appear to help decrease the incidence of cerebral palsy include maternal immunization against rubella, maternal abstention from smoking and alcohol consumption, magnesium sulfate given in premature labor, treatment for Rh incompatibility (see blood groups ), and treatment of hyperbilirubinemia ( jaundice ) in the newborn.

cerebral palsy denotes ‘a disorder of movement and posture resulting from a permanent, non-progressive defect or lesion of the immature brain’. There are a number of causative factors, most of which act before birth, but some can act up until the age of 2 years, to cause a non-progressive disorder of the still-developing brain. The overall incidence of cerebral palsy is about 5 per 2000 infants, although there are quite large variations between countries.

In some cases there are prenatal influences which cause failure of brain development: either definite genetic factors, inadequate supply of oxygenated blood to the fetal brain, rubella in the first trimester of pregnancy, toxoplasmosis transmitted across the placenta, or irradiation.

In about half of all instances cerebral palsy is associated with pre-term delivery and low birthweight. Compared to those at full term and of normal weight, such infants are particularly at risk of developing cerebral palsy if they suffer hypoxia or inadequate blood flow to the brain around the time of birth, or if they suffer brain infection (encephalitis, meningitis) or head injury during early life.

There are many variations in the types of cerebral palsy, and often there is a mixture of neurological abnormalities. The children may have increased muscle tone (spasticity), which most commonly affects all four limbs — the condition of spastic tetraplegia; or there may be spastic paraplegia, when the arms are apparently unaffected; or the so-called cerebral diplegia, often associated with premature birth, when the arms are less affected than the legs. There can also be hemiplegia, affecting one half of the body, or monoplegia, affecting one limb.

There may also be involuntary movements, such as the writhing (athetoid) type and various disturbances of co-ordination, depending on the parts of the brain affected. Less commonly, cerebral palsy takes the form of a hypotonic tetraplegia, with no spasticity, when the child has a mobility problem but with floppy muscles.

Children with cerebral palsy frequently have other severe handicaps. About half of them have an IQ less than 70, whilst 25% have an IQ above 90, compared with 3% below 70 and 75% above 90 in the general population. Epileptic seizures are more common than in the population overall. Retarded speech development may parallel the degree of learning disorder, but it is frequently also complicated by the problems of defective muscle control. Different forms of speech defect (dysarthria) accompany the different types of movement disorder.

Although the brain abnormality underlying the cerebral palsy is permanent and cannot be corrected, much help can be given to affected children and their families by way of physiotherapy, play and occupational therapy, speech therapy, orthopaedic surgery, and a variety of nutritional, mobility, and educational aids.

Forrester Cockburn

cerebral palsy Disorder mainly of movement and coordination caused by damage to the brain during or soon after birth. It may feature muscular spasm and weakness, lack of coordination and impaired movement or paralysis and deformities of the limbs. Intelligence is not necessarily affected. The condition may result from a number of causes, such as faulty development, oxygen deprivation, birth injury, haemorrhage or infection.