Growing  Pains

Growing Pains

Teenage girls are prime targets for ligament injuries

By Nancy Maes

Julissa Campos was playing soccer at Chicago’s Holy Trinity High School when she heard a sound like the snap of a rubber band. “When I pivoted, my upper body turned but my lower body didn’t, so something in my knee tore,” she recalls. “I couldn’t get back up because it was so extremely painful.” Campos had torn her anterior cruciate ligament (ACL), which is common in teenage female athletes, particularly those playing soccer, volleyball and basketball. Adolescent girls are more than two times as likely as boys in similar sports to injure their ACL, which stabilizes the knee.

Cynthia LaBella, MD, medical director at Lurie Children’s Institute for Sports Medicine, says, “Studies show that the gender disparity in ACL injury rates is most likely due to the fact that girls tend to use their muscles differently from boys during athletic maneuvers, such as jumping, landing, pivoting and changing directions. Girls tend to use their quadriceps to do more of the work rather than their hamstrings; whereas boys tend to use those two muscle groups more evenly, so there are more equal forces acting on the knee.”

“Also, girls tend not to engage all of their thigh, hip and core muscles and, instead, rely on their bones and ligaments to stop their joint motions; whereas boys tend to fire all their muscles around the joint to stabilize it and stop it from moving. Girls also tend to have one leg stronger than the other, so there is some asymmetry in terms of their lower-extremity muscle strength; whereas boys tend to have more equal strength between left and right legs.”

In addition, girls are more susceptible to injuring their ACL during their teen years. “The theory is that these changes happen during puberty when boys get a boost of testosterone, which leads to bigger, stronger muscles to go along with their increase in height and weight,” LaBella says. “Girls get the increase in height and weight, but don’t get the testosterone boost and the increase in muscle strength and size. So their ability to control their new body size with their muscles is much more limited.”

“It’s like the girls are stuck with the Hyundai-sized engine when the car size grows, while boys get the Cadillac-sized engine to go with their much bigger car,” LaBella says.

While physical therapy and rehabilitation may be an option for some people with ACL injuries, particularly those who are not very active, Brad Dunlap, MD, an orthopedic surgeon with the NorthShore Orthopaedic Institute, says that many choose surgery to reconstruct the ACL.

“The vast majority of both female and male athletes who have ACL injuries opt for surgery because they want to get back into their sport,” Dunlap says. Arthroscopic surgery to reconstruct the ACL is done on an outpatient basis. The new ACL can be created with a graft from a deceased donor or from the patient’s own tissue. “For adolescents, studies have shown much more positive results using their own tissue,” Dunlap says.

Rehab can last from six to nine months—not always easy for a teen athlete—before a patient can return to playing sports. “Rehabilitation is a big hurdle mentally for teens, but it allows the new ACL graft to heal back into the knee and be solid and stable enough to withstand the force of the pressure of doing sports,” Dunlap says. “The danger in going back too early is that you might rerupture the ACL.”

Lurie Children’s Institute for Sports Medicine offers a Knee Injury Prevention Program, a free training for coaches that teaches a 15-minute warm-up routine designed to reduce the risk of ACL injuries among female teen athletes. “Boys can benefit from the program, too,” LaBella says.

After ACL surgery, Campos had a hard time dealing with the lengthy rehab. “The process was very difficult because I was so angry that the injury happened,” she says. “But then I pulled through it and had almost my full range of motion back after six months.”