Ligamentous laxity of the knee during childhood and adolescence.

Abstract

There is little age- and sex-specific objective data concerning anterior knee translation in school-aged children. We aimed to establish age- and sex-specific baseline data for anterior knee translation of the knee in girls and in boys in grades 5 to 12. We also investigated whether a correlation exists between anterior knee translation and global joint laxity in girls in grades 5 to 12. A sample of convenience from a local school was used. Fifteen boys and 15 girls were randomly chosen from each grade, 5 to 12, to undergo anterior translation measurements with the KT2000 knee ligament arthrometer at 15, 20, and 30 lb of force. In addition, Beighton scores and bone age were determined. Anterior knee translation decreased with age in both girls and boys. Girls had greater anterior knee translation and end-point compliance than age-matched boys. In girls, there was a positive correlation between increased global joint laxity and increased anterior knee translation at 20 and 30 lb. However, hyperextension of the knee by itself was not a predictor of greater anterior translation. Anterior translation of the knee showed age and sex variation in school-aged children. These data are important in establishing a foundation of baseline data to understand sex differences in ligament development and function and to help guide injury prevention strategies. Level II diagnostic study.