A comparison of anterior knee laxity in female intercollegiate gymnasts to a normal population

Increased joint laxity may predispose an individual to ligamentous injury. Female gymnasts have a high incidence of ligamentous injury, including the anterior cruciate ligament (ACL). Previous authors have found a relationship between ACL disruption and preexisting ligament laxity. The purpose of this study was to compare anterior knee laxity in the knees of female intercollegiate gymnasts with those of a normal female population. A secondary purpose was to measure genu recurvatum and assess the relationship between it and anterior laxity in the knee. We tested 30 gymnasts and 30 control subjects having no history of ACL injury with the KT-1000 knee arthrometer. The quadriceps active, 133 N (30 lb) anterior drawer, and manual maximum tests were performed on the subjects' right knees along with goniometer measurements. Using a two-way analysis of variance (ANOVA) with repeating measures, we detected a significant increase in anterior laxity when comparing the 133 N to the manual maximum test, but no significant difference between gymnasts and nongymnasts. We concluded that gymnasts, as a group, are not abnormally lax when compared to an active population of similar age. Future comparison of the longitudinal data of those who incur ACL injury during their gymnastics careers may show whether individuals with increased laxity have increased risk of ligamentous injury.