The infamous ACL... what's the story behind these three letters? The ACL, or Anterior Cruciate Ligament, is one of the most important stabilizing structures of the knee. It provides support by holding the tibia (lower leg or shin bone) in place relative to the femur (upper leg or thigh bone), controlling the knee joint during activity. An ACL injury is usually season ending, typically requiring surgery followed by a rehabilitation period ranging from six to 12 months – depending if other structures are injured, the specific activity to be resumed, and the athlete's level of play.
How is this structure injured?
In about one-third of all cases, the ACL is torn by direct contact; two-thirds happen during a non-contact event. Non-contact injury events are related to a sudden deceleration, a rapid change of direction, or an abnormal motion such as hyperextension or an inward shift of the knee.
The ACL injury rate is approximately one in 3,000 or 200,000 cases per year in the U.S. However, many have called this injury an epidemic affecting female athletes. Statistics indicate that girls/women are four to eight times more likely than boys/men to injure the ACL with most injuries occurring to females during a non-contact event.
Here's the good news
Since the early 1980's, researchers have been looking at hormonal, structural, strength and mechanics to determine what causes the difference in injury rates between males and females. What the research is showing is that many non-contact injuries can be prevented through training hip and core strength and stability, implementing correct landing mechanics, as well as developing an over-all balance of strength in the hip and leg. Additionally, other preliminary results have indicated that certain athletes can be identified as having an increased risk of injury to the ACL. By targeting those athletes at greater risk, prevention programs can be implemented to reduce/eliminate injury occurrences.
The ACL injury is serious due to the usual need for reconstructive surgery and length of rehabilitation prior to returning to activity, but with the addition of strengthening and training programs, research is showing that injury rates can be decreased. Prevention can bring the epidemic under control, keeping all athletes on the field.
For more information about knee injuries or other sports medicine topics, call the Aurora Sports Medicine Hotline™ at (414) 219-7776 or (800) 219-7776.