Hixson earned eight gold medals, four silver medals, and six bronze medals across four summer Paralympic Games, from 1964 to 1976. At the 1964 Paralympics, held in Tokyo, she earned medals in swimming, club throw, discus throw, shot put, and javelin events. At the 1968 Paralympics, held in Tel Aviv, she won medals in shot put, javelin, and women's pairs lawn bowls events. At the 1972 Paralympics, held in Heidelberg, she won medals pentathlon, javelin, and discus throw events. And at the 1976 Paralympics, held in Toronto, she won medals in table tennis and javelin events.