In this form of cerebral palsy, which affects 70 to 80 percent of patients, the muscles are stiffly and permanently contracted. Doctors will often describe which type of spastic cerebral palsy a patient has based on which limbs are affected. The names given to these types combine a Latin description of affected limbs with the term plegia or paresis, meaning paralyzed or weak. Many individuals who have cerebral palsy have no associated medical disorders. However, disorders that involve the brain and impair its motor function can also cause seizures and impair an individual's intellectual development, attentiveness to the outside world, activity and behavior, and vision and hearing.
Mental impairment is even more common among children with spastic quadriplegia.
Seizures or epilepsy. As many as half of all children with cerebral palsy have seizures. During a seizure, the normal, orderly pattern of electrical activity in the brain is disrupted by uncontrolled bursts of electricity. When seizures recur without a direct trigger, such as fever, the condition is called epilepsy. Tonic-clonic seizures generally cause patients to cry out and are followed by loss of consciousness, twitching of both legs and arms, convulsive body movements, and loss of bladder control.