What is an ACL Tear?

The anterior crucial ligament is one of the most important ligaments in the knee and is one of the most common sports injuries in athletes. The injury occurs in sports that involve jumping, cutting, landing, or a sudden change in direction.

Overview

The ACL is a band of tissue in the knee that connect the femur to the tibia. It's main job is to prevent the tibia from sliding too far foward and control twist or pivoting movements. This ligament is greatly important in sports such as gymnastics, soccer, basketball, football, etc., because they involve high-impact and quick direction changes.

What Happens

The most common injury situation is a sudden stop or change in direction. When an awkward landing occurs, the knee will twist inward. Athletes often feel a pop and immediate instability, where the knee "gives out". Within the next few hours the knee will begin to swell and pain will increase. Inside the knee, the ACL fibers are either partially or completely torn, the small blood vessels rupture inside the joint, and blood and fluid quickly collect in the knee. Within the first 24-72 hours the knee will become swollen and stiff, range of motion becomes limited, and the quadriceps muscle may "shut down".

After Reconstruction

During ACL reconstruction surgery the torn ligament is removed and tunnels are drilled into the femur and tibia. Common graft options are hamstring tendon, patellar tendon, or quadriceps tendon. The graft is placed in the position of the ACL and is secured with screws or fixation devices. After the reconstruction swelling will gradually decrease and range of motion begins to restore. It's blood supply will slowly increase, and the graft with continue to strengthen and reorganize. 

Summary

An athlete's understanding of what happens during and after an ACL tear will allow for a more patient, safe, and aware approach to recovery. Rehab is a process that takes time and will create strength and control gradually.