Cerebral Palsy Health Article

Demographics

Cerebral palsy is one of the most common causes of chronic childhood disability. About 3,000 babies are born with the disorder each year in the United States, and about 1,500 preschoolers are diagnosed with cerebral palsy during the first three years of life. In almost 70% of cases, CP is found with some other disorder, the most common being

mental retardation. In all, around 500,000–700,000 Americans have some degree of cerebral palsy.

The prevalence of CP has remained very stable for many years. The incidence increases with premature or very low-weight babies regardless of the quality of care. Twins are also four times more likely to develop CP than single births.

Despite medical advances, in some cases the incidence of CP has actually increased over time. This may be attributed to medical advances in areas related to premature babies or the increased usage of artificial fertilization techniques.

Causes and symptoms

CP is caused by damage to an infant's brain before, during or shortly after delivery. The part of the brain that is damaged determines what parts of the body are affected.

There are a number of factors which appear to predispose a child to CP including:

• Exposure of the expectant mother to certain infections like rubella, toxoplasmosis and cytomegalovirus,
• Exposure of the expectant mother to certain chemicals like alcohol, cigarettes, cocaine and teratogenic (capable of causing birth defects) agents,
• Severe physical trauma to the mother during pregnancy, multiple births or maternal illness,
• Children who are born prematurely (less than 32 weeks) or who are very low birth weight (less than 1,500 grams or about 3⅓ pounds),
• Failure of the brain to develop properly or neurological damage to the infant's developing brain, including hypoxia (lack of oxygen) during birth,
• Bacterial meningitis and other infections, bleeding in the brain, lack of oxygen, severe jaundice, and head injury during the first few years of a child's life.

Cerebral palsy is categorized into four different groups that are characterized by different symptoms. Generally, babies that are severely affected may have obvious signs immediately following birth. Many infants do not display immediate CP symptoms. Parents are usually able to notice developmental delays, especially if they have another unaffected child. At the age of about three months, parents may notice a lack of facial expressions or that their baby does not respond to some sounds, or does not follow movement with their eyes. Certain other indicative symptoms may appear at around six months of age, including inability to lift the head or roll over and difficulty feeding. An affected child may be unable to crawl, sit, or stand without support and drooling is a common problem because of poor facial and throat muscle control. CP symptoms depend on the individual and the type of CP and, in particular, whether or not there is a mixed form of the condition.

The four main categories of cerebral palsy are:

• Spastic CP: Children with spastic CP have increased muscle tone. Their muscles are stiff and their movements can be awkward. Seventy to eighty percent of people with this disease have spasticity. Spastic CP is usually described further by what parts of the body are affected. In spastic diplegia, the main effect is found in both legs. In spastic hemiplegia, one side of the person's body is affected. Spastic quadriplegia affects a person's whole body (face, trunk, legs, and arms).
• Athetoid or dyskinetic CP: Children with athetoid CP have slow, writhing movements that they cannot control. The movements usually affect a person's hands, arms, feet, and legs. Sometimes the face and tongue are affected and the person has a hard time talking. Muscle tone can change from day to day and can vary even during a single day. Ten to twenty percent of people with CP have the athetoid form of the condition.
• Ataxic CP: Children with ataxic CP have problems with balance and depth perception. They might be unsteady when they walk. They might have a hard time with quick movements or movements that need a lot of control, like writing. Controlling their hands or arms when they reach for something is often difficult. People with ataxic CP can have increased or decreased muscle tone.
• Mixed CP: Some people have more than one type of CP, but this is most often a mixture of spasticity and athetoid movements, with tight muscle tone and involuntary reflexes.