Answer:
The anterior cruciate ligament (ACL) is so prone to injury because it connects the femur, tibia and middle of the knee and is a crossing point of these three bones. The ACL prevents the tibia from sliding too far underneath the femur and also prevents over-rotation of femur on the tibia. Hence, any movement of the knee beyond its range of motion may result in ACL injury.
Step-by-step explanation:
Anterior Cruciate Ligament (ACL) is the ligaments that crosses the middle of the knee and connects the thighbone (femur) with shinbone (tibia) and helps in stabilizing the knee joint. This ACL ligament may get injured due to sudden stop or change in direction, landing awkwardly, and receiving a direct blow to the knee while playing sports. In ACL injury, the knee swells and cannot bear weight. The ACL upon injury might tear down or stretch which makes standing and walking completely unbearable.