Anterior knee laxity is greater in athletic females who attain menarche at a younger age.

Abstract

Females with above-average anterior knee laxity values are at increased risk of anterior cruciate ligament (ACL) injury. The purpose of this study was to examine the effects of menarche age (MA) and menarche offset on anterior knee laxity in young, physically active women. Anterior knee laxity (KT-2000) and menstrual characteristics (per self-report) were recorded in 686 Slovenian sportswomen from team handball, volleyball and basketball club sports (average years sport participation: 7.3 ± 3.6 years). Females were stratified into four groups based on their self-reported age at menarche: 9-11, 12, 13 and 14+ years. Anterior knee laxity was compared across MA groups using a univariate analysis of variance (ANOVA) with Bonferroni correction, with and without controlling for factors that could potentially differ between groups and influence anterior knee laxity. Females were then stratified into four groups based on the number of years they were away from their age at onset of menarche. Groups were compared using a univariate ANOVA with Bonferroni correction, with and without controlling for factors that differed between groups and could influence anterior knee laxity. Anterior knee laxity was greater in females who attained menarche at 12 years of age (6.4 ± 1.5 mm) or younger (6.6 ± 1.6 mm) compared to 14 years of age or older (5.8 ± 1.2 mm) (p < 0.001; partial η2 = 0.032). Anterior knee laxity was 0.7-1.4 mm greater in females who were 5 or more years away from menarche compared to those who were within 2 years of menarche (5.8 ± 1.3 mm; p < 0.001). Anterior knee laxity is greater in females who attained menarche at a younger age and in females who are 5 or more years postmenarche. Age of menarche represents a critical pubertal event that is easy for women to recall and may provide important insights into factors that moderate anterior knee laxity, a risk factor for ACL injury in women. Level IV.