A Cross-Sectional Study of the Relationship between Cortical Bone and High-Impact Activity in Young Adult Males and Females

Abstract

Sexual dimorphism in skeletal development is well recognized and likely to contribute to gender differences in fracture risk (1), such as the relatively high risk of hip fractures in elderlywomen(2). At the hip, these differences have been reported to emerge during the adolescent growth spurt and to be comprised largely of greater periosteal apposition in males, leading to greater femoral neck width and bending strength (3). More rapid periosteal boneformationin males, leading to greater corticalbonesize, has also been reported at the mid-femur (prepubertal children and young adults combined) (4), mid-tibia (peripubertal children) (5),anddistal tibiaandfemoral neck (18 yr olds) (6). Our previous cross-sectional study of hip structure in peripubertal children from the Avon Longitudinal Study of Parents and Children (ALSPAC) revealed that emergence of these differences coincided with the onset of puberty (7).Any suggestion that sex steroids contribute to sexual dimorphism of the skeleton is consistent with previous findings from rodent studies suggesting that estrogens and androgens respectively suppress and stimulate periosteal growth (8, 9).