The Cause of Noncontact Anterior Cruciate Ligament Injuries

I took a break from research reviews.  Well not a review, kind of a filtering down to help you, compared to a full-blown research analysis.

During the break I was getting feedback from you on what you want to see.

I have heard you loud and clear on the things that you want to see when it comes to injuries – elbow injuries, ankle injuries, shin splints, iliotibial band syndrome, tensor fascia latae issues, acute injury recovery tips, chronic pain injury tips, and dealing with pain at the back of the knee when walking.  I will be working on this throughout 2011.

Let me clear out a few of the papers that I have put to the side and still need to look at.  Now let’s get to the article.

What They Looked At

They looked at 10 anterior cruciate ligament (ACL) injury videos from women during handball and basketball in order to determine what biomechanical factors lead to the ACL injury.

Here is an example of the injury that they looked at:

What they did for the video analysis was very cool in the article.

Cool Points

Few cool things that they said in the introduction:

  • Noncontact ACL injuries in women occurring during cutting or one leg landing movements.

What They Found

  • At initial contact there was a valgus movement (knee going in).
  • The tibia rotated internally and then externally.
  • ACL injury occurred at about 40 milliseconds mark after initial contact.
  • The mechanism of injury was the valgus movement of the knee with the tibia rotated internally, and then after the tear, the tibia externally rotating.
  • The valgus and internal rotation movements contributed to the ACL injury.

A few other things that are not in the abstract:

  • 6 injured left knee and 4 right.
  • ACL injury occurred during the game and were handling the ball.
  • There was a rapid valgus movement of 12 degrees.
  • There was a low flexion angle and injury.

Here is a great visual from the paper that I thought was great on how they feel a noncontact ACL injury occurs:

Take Home Message

Focus of a Prevention Program – Prevention programs should focus on good cutting and landing technique with knee flexed and without valgus loading of the knee.

More than Lines and Side Shuffle – I remember when I played basketball.  All we would do for prevention were lines, side shuffles, and drills.  This does not cut it anymore.  More needs to be done with landing and preparing the knee in all planes of movement.  This can easily be done with an 8 minute program that focuses on neuromuscular re-education of the knee.  This can be done before a game or as a drill during practice.

Where to get more info – Koga H, Nakamae A, Shima Y, Iwasa J, Myklebust G, Engebretsen L, Bahr R, Krosshaug T. (2010). Mechanisms for noncontact anterior cruciate ligament injuries: knee joint kinematics in 10 injury situations from female team handball and basketball. Am J Sports Med. 2010 Nov;38(11):2218-25. Epub 2010 Jul 1.

I go through my knee injury rehabilitation exercises here:

If you are looking for other ACL articles to read, I have a stack of them:


Preventing a Second ACL Injury
Knee Pain Due to a Sloppy Knee
ACL Injuries in Female Athletes

Thank you so much for reading.  Let me know if you have any questions or what you think in the comment box below.

Rick Kaselj, MS