heterogeneous group of nonprogressive motor disorders caused by chronic brain injuries that originate in the prenatal period, perinatal period, or first few years of life; the four major subtypes are spastic, athetoid, ataxic, and mixed cerebral palsy, with spastic forms being the most common; the motor disorder may range from difficulties with fine motor control to severe spasticity in all limbs; spastic diplegia (Little disease) is the most common subtype, and is characterized by spasticity that is more prominent in the legs than in the arms.