An anterior cruciate ligament (ACL) tear is an injury to the knee commonly affecting athletes, such as soccer players, basketball players, skiers, and gymnasts. Nonathletes can also experience an ACL tear due to injury or accident. Approximately 200,000 ACL injuries are diagnosed in the United States each year. It is estimated that there are 95,000 ruptures of the ACL and 100,000 ACL reconstructions performed per year in the United States. Approximately 70% of ACL tears in sports are the result of noncontact injuries, and 30% are the result of direct contact (player-to-player, player-to-object). Women are more likely than men to experience an ACL tear. Physical therapists are trained to help individuals with ACL tears reduce pain and swelling, regain strength and movement, and return to desired activities.