Introduction to the ACL / Mechanism Of Injury
- Posted on: Nov 3 2016
The knee is composed of various structures, including bones, muscles, cartilage, ligaments and
tendons. Various injuries can occur to the knee, whether it be fractures, dislocation, ligament
tears, or others.
This series of posts will be focusing on the Anterior Cruciate Ligament (ACL), and what happens when someone suffers an injury to this ligament.
What is the ACL?
The ACL is a very strong ligament in the knee. A ligament is a dense band of connective tissue
that connects one bone to another bone. In the case of the ACL, it connects the upper leg bone or
femur to the lower leg bone, the tibia. The function of the ACL is to prevent the tibia from
sliding too far forward in front of the femur. It also prevents the tibia, from rotating too much.
How does it get injured?
Injuries to the ACL are classified as contact or non contact injuries. An example of a contact
injury, would be a football player tackling another player and hitting them in the knee.
A non contact injury, which is more common, is caused by forces generated within the athlete’s
body. This usually involves some more of twisting motion (remember one of the ACL’s
functions is to prevent too much rotation), the knee shifting too far forward, or the knee
collapsing in. This is seen most often when athletes plant their foot and pivot or twist on it. For
example, a soccer player kicking a ball or basketball player pivoting his or her foot.
How do you know if you injured your ACL?
In the event of a full tear or rupture, people normally report hearing an audible “popping noise”
followed by a lot of pain and inability to put weight through that leg.
(http://orthoinfo.aaos.org/topic.cfm?topic=a00325 )
It doesn’t always have to be completely torn though. In the event of a partial tear or smaller
injury to the knee, an individual may experience pain in the knee, notice swelling around the
knee, feel that the knee gives out, catches, or locks, and other symptoms.Continue Reading
If you experience knee pain, as a result of a specific injury or not, and any of the other symptoms
mentioned above, you may want to seek the advice of a medical professional, like a physical
therapist.
Below are two resources that talk more about the knee, injuries that can occur to it, and the ACL.
http://orthoinfo.aaos.org/topic.cfm?topic=a00325
http://www.physio-pedia.com/Anterior_Cruciate_Ligament_(ACL)_Injury
Posted in: Knee
