Cerebral palsy (CP) is a group of disorders that affect a person’s ability to move and maintain balance and posture. CP is the most common motor disability in childhood. Cerebral means having to do with the brain. Palsy means weakness or problems with using the muscles. CP is caused by abnormal brain development or damage to the developing brain that affects a person’s ability to control his or her muscles.
All people with CP have problems with movement and posture. Many also have related conditions such as intellectual disability; seizures; problems with vision, hearing, or speech; changes in the spine (such as scoliosis); or joint problems (such as contractures).
CP is caused by abnormal development of the brain or damage to the developing brain that affects a child’s ability to control his or her muscles. There are several possible causes of the abnormal development or damage. People used to think that CP was mainly caused by lack of oxygen during the birth process. Now, scientists think that this causes only a small number of CP cases.
The abnormal development of the brain or damage that leads to CP can happen before birth, during birth, within a month after birth, or during the first years of a child’s life, while the brain is still developing. CP related to abnormal development of the brain or damage that occurred before or during birth is called congenital CP. The majority of CP (85%–90%) is congenital. In many cases, the specific cause is not known. A small percentage of CP is caused by abnormal development of the brain or damage that occurs more than 28 days after birth. This is called acquired CP, and usually is associated with an infection (such as meningitis) or head injury.