Experienced athletes know that injury to the knee's anterior cruciate ligament (ACL) can mean spending the season on the sidelines. While ACL injury is uncommon in the general population, athletes — especially young women who play basketball, soccer or volleyball — are susceptible. Treatment of an ACL injury can get you back to your sport, but the best defense is a strong offense. If you're active in a sport that involves pivoting or jumping, learn how your training program can help you avoid an ACL injury.

Ligaments are strong bands of tissue that attach one bone to another. The anterior cruciate (KROO-she-ate) ligament, one of two ligaments that cross in the middle of the knee, connects the thighbone (femur) to the shinbone (tibia) and helps stabilize the knee joint. The ACL may tear, either partially or completely, as a result of a hard twist, sudden stop while running, jump landing or direct blow to the knee. You may experience a loud, painful pop when the ligament is first injured, followed by swelling of the knee.

The pain and swelling of an ACL injury can last for several weeks. While some people can continue to function, most say their knee feels unstable or loose. It may give way if you return to your sport. Short-term treatment can relieve the pain and inflammation, but it takes months for an ACL injury to heal completely. Treatment may include surgery to rebuild the torn ligament, along with an intense rehabilitation program.