Studies have shown that the injury rate to the knee's anterior cruciate ligament (ACL) is up to eight times higher for women than it is for men, particularly in sports requiring stopping and jumping tasks. Such injuries in young athletes often require surgery and prolonged rehabilitation.
The ACL is one of one of two ligaments that cross within the knee joint to prevent the leg bone (tibia) and thigh bone (femur) from slipping forward or backward out of the joint. Although ACL injuries are more than 70 percent sports-related, most occur when there is no direct physical contact between athletes.
Writing in the March/April issue of the American Journal of Sports Medicine, authors from the University of North Carolina at Chapel Hill point to a particular risk factor for ACL injury in women: greater anterior shear force, or forward slippage of the tibia, that is applied to the knee during sports-related stop-jump tasks.
"Data from soccer, volleyball and basketball suggest that women are two to eight times more likely to have an ACL injury. During the landing phase of stop-jump activities in those sports, significant shears occur, the tibia moving forward. And if the tibia moves too far forward of the ACL on the femur, it tears the ACL," said senior author Dr. William E. Garrett, Jr., Frank C. Wilson Distinguished Professor and chair, department of orthopaedics in the medical school.
The study involved three-dimensional videography and force-plate data to record three stop- jump tasks of ten women and ten men, recreational athletes ages 19 to 25 years. A recreational athlete was defined as someone who competes three times or les
Contact: Lslie H. Lang
University of North Carolina School of Medicine