As I was backing out of a driveway the car suddenly accelerated in reverse. The brake did not stop or slow the vehicle. As a result the car's right fender hit a large oak tree. There was damage to the fender, the door and to the undercarriage. In addition, my wife who was sitting in the passenger seat was thrown back and she struck her head on the top seat belt connection. She had a cut in the back of her head that required an emergency room visit to the local hiospital. They did a CAT scan and they used seven staples close the wound. There were several messages flashed on the dash that indicated brake and cruise control issues. These messages wer of very short duration and could not be recazlled.