Review of cerebral palsy, Part I: Description, incidence, and etiology.

Cerebral palsy (CP) is a nonprogressive disorder of motor function. Although it has been recognized for more than a century, much remains unknown regarding its etiology. It has been estimated that 17 to 60 percent of the cases of CP have no known perinatal or neonatal complications. Undocumented antenatal events may cause brain damage or increase the infant's vulnerability to future events. The prevalence of CP has remained relatively constant; however, its incidence in the preterm population has increased with the improving survival of the very low birth weight infant.