forces caused by a fall to the knee rather than the ankle or lower leg. The ACL injury usually occurs when the knee is forcefully twisted, or hyper-extended. Many patients recall hearing a loud pop when the ligament tears, and feel the knee give way. This injury has received a great deal of attention from orthopedic surgeons over the past 15 years and very successful operations to reconstruct the torn anterior cruciate ligament have been performed.The tearing oh the posterior cruciate ligament is another sports related knee injury, though less common than the ACL. This injury can occur when the knee is forcefully twisted or hyper-extended, but other ligaments are usually injured or torn, before the posterior cruciate ligament (PCL) is torn in these injuries. The most common way for the PCL alone to be injured is from a direct blow to the front of the knee while the knee is bent. If the tibia moves too far back the PCL can rupture. This is a common cause of injury to the PCL during an automobile accident. As the automobile strikes another and stops suddenly, the front passenger or driver slides forward. The bent knee hits the dashboard just below the kneecap. This forces the tibia backward on the femur tearing the PCL. The same force can occur during a fall on the bent knee, where the force of the fall on the tibia pushes it back against the femur and tears the PCL. The PCL may not be the only ligament injured when the knee is injured violently, such as a severe hyperextension injury where the knee is forced backwards (bends in the opposite direction that is should). This injury may occur when the foot is planted on the ground and the knee is struck from the front, (such as with a car bumper, or another player in soccer or football). It is not uncommon to see several ligaments injured in addition to the PCL during a true knee dislocation.Cartilage tears are another type of knee injury and can be very painful. The most common cause is an ...
