"Prior to conducting our study, we understood that previous ankle injury was a strong risk factor for a repeated ankle injury," said Bruce Beynnon of the University of Vermont.
To analyze ankle ligament injury risk factors, Beynnon and colleagues measured factors in 901 Vermont high school and collegiate athletes who logged a total of 50,680 "person-days" of exposure to soccer, basketball, lacrosse or field hockey over four years. Athletes who suffered prior ankle trauma were not included.
Risk of ankle injury was highest among female basketball athletes who are at significantly greater risk than male basketball athletes, according to the study.
The researchers found that the women in the study were at increased risk of suffering their first ankle injury when there was a strength imbalance in the muscles that control the side-to-side movement of the ankle. They also identified several non-modifiable risk factors, including alignment of the muscles in the front of the leg with the knee; loose ankles, which are suggestive of weak ligaments or structural problems; and equally dominate legs.