Cortical bone maintenance and geometry of the tibia in prehistoric children from Nubia's Batn el Hajar

Abstract

The relationship between advancing age in adults and patterns of cortical bone maintenance has been extensively documented for archaeological populations (Dewey, et al., 1969; Van Gerven et al., 1969; Perzigian, 1973). Most recently, this research has been expanded to include a more thorough consideration of the geometric properties of bone in relationship to adult age changes (Martin and Atkinsin, 1977; Ruff and Hayes, 1983). To date, however, few studies have documented subadult patterns of cortical bone maintenance in archaeological populations and none have incorporated the relationship between patterns of cortical bone loss and gain and the changing geometric properties of growing bone. Using a sample of 172 tibias from children excavated from the Medieval Christian site of Kulubnarti, located in Nubia's Batn el Hajar, the present research examines the relationship between percent cortical area, bone mineral content, and cross-sectional moments of inertia. Among these children, bone mineral content increases steadily from birth in spite of a reduction in percent cortical area during early and late childhood. It appears, therefore, that tissue quality of the bone is not adversely affected by the reduction. Furthermore, the reduction in percent cortical area in later childhood corresponds to a dramatic increase in bending strength measured by cross-sectional moments of inertia. Thus, whether this cortical reduction is due entirely or in part to either normal modeling or nutritional stress, the tissue and organ quality of the bone is not adversely affected.

Bone quantity and quality in past populations

“…There is some evidence from the archaeological Nubian material that suggests that some type of compensatory mechanism was occurring with the reduction in bone mass to prevent a compromise in bone quality. For example, investigation of cortical maintenance in prehistoric Nubian children found that growth mechanisms were able to compensate for observed nutrition-related and modeling bone loss to maintain bone quality (Van Gerven et al, 1985).…”

Do environmental disturbances of an individual's growth and development influence the later bone involution processes? A study of two mediaeval populations

“…It was then that large-scale studies on the nature and rate of bone loss in North African prehistoric and historical human groups from Sudanese Nubia were planned. The studies resulted in numerous detailed and exhaustive works (Dewey et al, 1969a,b;Armelagos et al, 1972Armelagos et al, , 1982Mielke et al, 1972;Martin & Armelagos, 1979;van Gerven et al, 1985). Parallel to the above mentioned studies, research on human bone remains from the North American continent was initiated.…”

Effects of age and occupation on cortical bone in a group of 18th–19th century British men

“…Cortical thickness has been used as an osteological indicator of stress (Cox et al, 1983), particularly nutritional stress, albeit to a much lesser extent than other markers such as stature or dental enamel hypoplasias. Most workers studying cortical bone as a stress indicator have focused on patterns of growth in cortical thickness, using juvenile skeletons (Cook, 1979;Huss-Ashmore et al, 1982;Hummert, 1983;van Gerven et al, 1985;Mays, 1985Mays, , 1995Mays, , 1999a. Some studies of adult remains have also taken this perspective (Hatch et al, 1983;Pfeiffer and King, 1983;Owsley, 1991), deficiencies of peak cortical bone in adulthood being taken as indicators of unfavorable conditions during the growth period.…”