Socioeconomic differences in growth of metacarpal II during adolescence in females: Interactions with sexual and skeletal maturity

Abstract

In order to study the role of socioeconomic status (SES) in growth of the second metacarpal (MC) during adolescence in females, 352 cross-sectional observations of 34 girls from high SES 11-17 years of age were compared with 876 cross-sectional observations of age-matched low to middle SES Turkish girls. Values for MC length (L), L/outer diameter (D), total cortical thickness (C), C/L, C/D%, stature, weight, stages of secondary sexual development (SSD), and skeletal age (SA) were significantly greater in the high SES, while outer (D) and medullary diameter (M), C-area, M-area, and MC-volume were significantly smaller. The estimated total average increase in C/year was 0.21 versus 0.22 mm in low-middle and high SES girls, respectively, being twice as high before 14 years compared with at 14-17 years. The decrease in M started earlier and was steeper in the high SES. M was significantly smaller in the high SES when SSD or years before and after menarche was controlled, and also after SA of 14 years, while C was not significantly different under these conditions. M and D values for a given L were significantly greater in low-middle SES girls, while differences in C were not significant. It was concluded that reduced C for age in low-middle SES girls is a reflection of their overall slower growth relative to high SES girls, and once they catch up in growth the difference in C between groups is no longer significant. However, there still is a greater D for a given L, which is mainly due to significantly greater M for L, which was present at the beginning of the study. (C) 1997 Wiley-Liss, Inc.