"With more girls competing in soccer, basketball, gymnastics and volleyball—sports requiring maneuvers such as jumping and landing, or quick stops and turns—more cases of ACL injuries are being seen," says Dr. Ahmad, director of the Center for Pediatric and Adolescent Sports Medicine at Morgan Stanley Children's Hospital and assistant professor of orthopaedic surgery at Columbia University College of Physicians and Surgeons.
The study posits two primary reasons for girls' increased susceptibility to ACL injuries. First, adolescent girls tend to develop increased quadriceps strength, while not increasing hamstring strength. With very strong quads overpowering the hamstrings, an imbalance occurs, leading to undue stress on the ACL. Second, girls become skeletally mature earlier during puberty, and they tend to perform their sports activities in a more upright position that adds stress to the ACL.
The study followed 53 female and 70 male recreational soccer players, aged 10 to 18. Greater knee laxity—one indication of risk for ACL injury—was found among mature girls (8.85 mm), especially when compared to mature boys (7.33 mm). Previous research has shown that estrogen may contribute to laxity and weakened ACLs. None of the study participants had evidence of damage to their ACLs. The study also found mature girls had significantly greater quadriceps-to-hamstring ratio (2.06) when compared to immature girls (1.74), immature boys (1.58) and mature boys (1.48).
Dr. Ahmad suggests tips for girls on how to prevent ACL injuries, including making them more aware of their upright position during activities like landing from a jump and training them to assume a more flexed stance. He also suggests strengthening of hamstring, hip and core muscles.
'When an injury takes place, the child's knee and surrounding areas should be iced and elevated to prevent inflammation,' says Dr. Ahmad. 'With any persisting pain or lack of mobility, parents should consult with their physician.'