ACL Injuries in the Female Athlete
 
 

 

 

ACL Injuries in the Female Athlete

 

With increased participation in sports by female athletes over the past 10 years we are finding more severe knee injuries within this population, in particular, more women are vulnerable to anterior cruciate ligament (ACL) injury.  Severe knee injury is defined as an injury that takes an athlete out of sports participation for more than 21 days.  In a recent study by the National Athletic Trainers’ Association, severe injuries account for 14.9% of all high school sports-related injuries.  After football injuries, wrestling, girls’ basketball and girls’ soccer maintained the highest levels of injury, with girls’ volleyball showing the next highest level of ACL injury.  According to the National Collegiate Athletic Association (NCAA), female basketball players are four times as likely to suffer from an ACL tear as male basketball players. 

The ACL connects the tibia (shin bone) and femur (thigh bone), providing anterior stability to the knee for activities requiring running, jumping, landing, deceleration, twisting, turning, and changing directions quickly on an extended (straight) knee.  About 80% of sports-related ACL tears are "non-contact" injuries. This means that the injury occurs without the contact of another athlete.  Most often ACL tears occur when pivoting or landing from a jump. The knee gives-out from under the athlete when the ACL is torn. When cutting, or landing from a jump, females have been observed with their knees more extended and rotated inward.   Also, studies have shown females to have a delay in muscle recruitment, poor hamstring recruitment patterns, and less joint stiffness. Researchers also believe ACL injure may be due to differences in hormone levels on ligament strength and stiffness, neuromuscular control, lower limb biomechanics, ligament strength and fatigue.  Lower limb biomechanics show that female athletes have a wider pelvis than males which also causes an increased inward or Q-angle of the knee.  A twisting injury in a males’ knee may only stretch his ACL; however, because of the greater Q angle, the same type of twisting injury in females’ knee may cause a complete ACL tear.  Increased rearfoot pronation also contributes to an increase in the inward angle of the knee, increasing the prevalence of ACL injury.

Prevention of ACL injury in the female athlete is critical to the success of the athletes’ career.    A team of researchers at the University of North Carolina-Chapel Hill led by Spero G. Karas, MD, assistant professor of orthopaedics at Emory University, Atlanta, found that female athletes tend to hold their trunks and hips in a more erect posture while performing running and jumping maneuvers, suggesting that this difference may contribute to the increased risk of ACL injury. Female athletes should be conditioned to place themselves in a more protective position in sport activities, and, thereby, reduce ligament injury.  The Sports Performance Center has been working with female athletes in the prevention of ACL injury using stretching, strengthening, and proprioception training to reduce injury in at the high school level.  Also, a thorough evaluation of the female athlete by a physical therapist is critical in the prevention process.  Cybex evaluations are used to assess the strength of the female athletes’ lower extremity strength deficits as well as evaluation of the foot to correct any excess rearfoot pronation that may be present. There is no doubt that improving one's proprioception, strength, and posture will help reduce the incidence of ACL injuries in females.