Mixed Cerebral Palsy:
About 10 percent of children with cerebral palsy have what is known a mixed-type cerebral palsy. These children have both the tight muscle tone of spastic cerebral palsy and the involuntary movements of athetoid cerebral palsy. This is because they have injuries to both the pyramidal and extrapyramidal areas of the brain. Usually the spasticity is more obvious at first, with involuntary movements increasing when the child is between nine months and three years old. The most common mixed form includes spasticity and athetoid movements, but other combinations are also possible.