Cerebral palsy is caused by injuries or abnormalities of the brain. Most of these problems occur as the baby grows in the womb. But they can happen at any time during the first 2 years of life, while the baby's brain is still developing.
In some people with cerebral palsy, parts of the brain are injured due to a low level of oxygen (hypoxia) in those areas. It is not known why this occurs.
Premature infants have a slightly higher risk of developing cerebral palsy. Cerebral palsy may also occur during early infancy as a result of several conditions, including:
In some cases, the cause of cerebral palsy is never determined.
Symptoms of cerebral palsy can be very different between people with this group of disorders. Symptoms may:
Be very mild or very severe
Only involve one side of the body or both sides
Be more pronounced in either the arms or legs, or involve both the arms and legs
Symptoms are usually seen before a child is 2 years old. Sometimes symptoms begin as early as 3 months. Parents may notice that their child is delayed in reaching developmental stages such as sitting, rolling, crawling, or walking.
There are several different types of cerebral palsy. Some people have a mix of symptoms.
Spastic cerebral palsy is the most common type. Symptoms include:
Muscles that are very tight and do not stretch. They may tighten even more over time.
Abnormal walk (gait): arms tucked in toward the sides, knees crossed or touching, legs make "scissors" movements, walk on the toes
Joints are tight and do not open all the way (called joint contracture)
Muscle weakness or loss of movement in a group of muscles (paralysis)
Symptoms may affect one arm or leg, one side of the body, both legs, or both arms and legs
The following symptoms may occur in other types of cerebral palsy:
Abnormal movements (twisting, jerking, or writhing) of the hands, feet, arms, or legs while awake, which gets worse during periods of stress
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Nass R, Ross G. Developmental disabilities. In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley's Neurology in Clinical Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 61.
Noritz GH, Murphy NA; American Academy of Pediatrics Neuromotor Screening Expert Panel. Motor delays: early identification and evaluation. Pediatrics. 2013;131:e2016-2027. PMID: 23713113 www.ncbi.nlm.nih.gov/pubmed/23713113.
Joseph V. Campellone, MD, Division of Neurology, Cooper University Hospital, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.