Several recent studies, which include a controlled study of first-time anterior cruciate ligament (ACL) injuries in Vermont high school and college athletic team members—conducted by Bruce Beynnon, PhD, University of Vermont McClure Professor of Musculoskeletal Research, Director of Research, Department of Orthopaedics and Rehabilitation and research colleagues—have examined multiple factors such as the size of the femoral notch to explain why some people are at greater risk for injury than others.
In a study published in the August issue of American Journal of Sports Medicine, Dr. Beynnon and colleagues have “very accurately characterized the incidence rate and magnitude of this problem in Vermont.”
The investigators examined 88 student athletes (27 male and 61 female) who suffered first-time, noncontact ACL injuries during the study and compared their measurements, which were taken using MRI, to a non-injured control group of 88 athletes (same male-female breakdown) from the same teams, with the same extrinsic factors (eg, environment, playing surface, training, footwear, level of competition, and coaching). One of the findings that study authors discovered is that the risk of injury increased as the size of the femoral notch and ACL decreases.
In a parallel five-year epidemiological study, also published in same issue, researchers reported on the effects of level of competition, sport, and sex on the incidence of first-time noncontact ACL injuries.
For this study, Dr. Beynnon and colleagues collected data from 38 institutions located throughout Vermont. Colleges reported 48 ACL injuries during the sport seasons studied, while high schools reported 53 injuries. The research team learned that college athletes had a significantly higher ACL injury risk than high school athletes and that female athletes were two times more at risk for ACL injuries than males. In comparison to athletes taking part in Lacrosse, risk of ACL injury was significantly greater among those participating in soccer and rugby.
“An athlete’s risk of having a first-time noncontact ACL injury is independently influenced by level of competition, the participant’s sex, and type of sport they participate in, and there are no interactions between their effects. Female college athletes have the highest risk of having a first-time noncontact ACL injury among the groups studied,” Dr. Beynnon and colleagues stated.