Of course, Ritalin is not perfect and you cannot expect a miracle. Stimulants don't work for all ADHD children and nothing will transform a problem child into an angel. What you must look for is significant improvement worth the effort and the risk. That's all, just significant improvement.
Head injuries include both injuries to the brain and those to other parts of the head, such as the scalp and skull. Head injuries can be closed or open. A closed (non-missile) head injury is where the dura mater remains intact. The skull can be fractured, but not necessarily.
A closed head injury is different from an open head injury, in that no object actually penetrates the brain. Closed head injuries can be diffuse, meaning that they affect cells and tissues throughout the brain; or focal, meaning that the damage occurs in one area.