In the early evening on October 1, 2003, Christina Crosby was three miles into a 17 mile bicycle ride, intent on reaching her goal of 1,000 miles for the riding season. She was a respected senior professor of English who had celebrated her 50th birthday a month before. As she crested a hill, she caught a branch in the spokes of her bicycle, which instantly pitched her to the pavement. Her chin took the full force of the blow, and her head snapped back. In that instant, she was paralyzed.