Posterior cruciate ligament injury happens far less often than does injury to the knee's better known counterpart, the anterior cruciate ligament (ACL). The posterior cruciate ligament and ACL help to hold your knee together. If either ligament is torn, you may experience pain, swelling and a feeling of instability.
Ligaments are strong bands of tissue that attach one bone to another. The cruciate (KROO-she-ate) ligaments connect the thighbone (femur) to the shinbone (tibia). The anterior and posterior cruciate ligaments form an "X" in the center of the knee.
While a posterior cruciate ligament injury generally causes less pain, disability and knee instability than does an ACL tear, it can still sideline you for several weeks or months.