From an interview with
Dr. Zachary DiPaolo
McLeod Orthopaedics Florence

A tear in your knee’s Anterior Cruciate Ligament is a serious injury that will probably require surgical intervention. McLeod Orthopedic Surgeon Dr. Zachary DiPaolo describes the types of ACL tears and their consequences.

Here is an overview of Dr. DiPaolo’s comments:
The anterior cruciate ligament or ACL is a ligament in the inside part of your knee. You can’t feel it or see it by just examining or touching the knee. It happens to be very highly correlated with athletic injuries. You do have other ligaments in your knee. There is a posterior cruciate ligament (PCL), which crosses just behind the ACL. You can injure that one as well. It’s just very less common. You also have medial and collateral ligaments that are on the outside of the knee. The ligament’ purposes is to keep the knee stable during regular walking and in cutting, pivoting and jumping sports. The ACL just happens to be of those four main ligaments, the one that’s injured most frequently.

ACL tears come in two types — non-contact and contact. The majority of ACL tears happened to be Non-Contact injuries. A person is running. They plant their foot, twist to pivot and change directions and the knee buckles. ACL tears we see most frequently occur in soccer or basketball. Contact ACL injuries more frequently occur in football. A player is trying to bring you down any way they can and they collide with your knee.

We have really good mechanisms, biomechanical studies on how the ACL actually tears in a non-contact injury and a pivoting mechanism is probably the easiest way to think about it. As far as contact injuries though, that can be from a car accident, a bad football tackle or some of traumatic injury.

Typically, when a person tears an ACL, they hear or feel a “pop” in their knee. Sometimes, even people near them can hear the pop. Most of the time, there’s immediate pain and a significant amount of swelling. So, the rule of thumb in the orthopedic sports world is that a young person who had felt or heard a pop with significant swelling is that they have an ACL tear, until proven otherwise.

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