A high school point guard dribbles down the basketball court, cuts to her right, and suddenly falls to the floor in pain. A collegiate soccer player lunges the wrong way. A softball player hears a loud pop. All three young women have anterior cruciate ligament (ACL) tears, putting them on the sidelines—and on the operating table.
For reasons yet to be explained, female athletes are 2½ to four times more likely to tear ACLs than men, depending on the sport. Strengthening and stretching programs help. Now, new research may help predict the season-ending knee injury, while there’s still time to prevent it.
“An ACL injury for a female athlete doesn’t just affect her at the moment of injury; a high percentage experience long-term consequences such as osteoarthritis and disability: This is unacceptable,” says Mette K. Zebis, Ph.D., from the Institute of Sports Medicine Copenhagen, who was lead author of a recent study on ACL injuries. “If we can identify those at risk for the injury, we can help prevent it.”
The study, published in the October issue of the American Journal of Sports Medicine, is the first to discover that levels of electrical activity in specific muscles may predispose a female athlete to ACL injury.
The research team utilized electromyography (EMG) technology to test 55 healthy elite female athletes while they performed “side-cutting,” a maneuver linked to many noncontact ACL injuries. Preliminary data show that lower EMG signals in the back of the thigh and higher activity in the front of the thigh are linked to subsequent ACL tears.
The high-risk zone developed by Dr. Zebis and her colleagues is a “promising” tool. Clinical recommendations will be based on the findings of additional studies.
“Our study provides a foundation,” says Dr. Zebis. “Larger studies should be conducted to confirm our suspicions that this screening tool will be a huge asset in preventing future female athletic injuries.”