Cross-sectional data on 2799 subjects from five different populations and longitudinal data on 113 older adults indicate continuing adult bone growth in the second metacarpal. Similar B-decade increases in the size of the cranium confirm continuing bone growth as a general phenomenon not necessarily related to weightbearing or flexion stress and representing an increase of approximately 10% in skeletal volume concomitant with the major age-associated decrease in skeletal mass.In 1964, Smith and Walker provided cross-sectional radiographic evidence for continuing "expansion" of the femur in women aged 45-90. Trotter and Peterson ('67), using skeletalized femora have given confirmation to this trend. Epker, Kelin and Frost ('65) similarly reported an increase in the size of the periosteal envelope through the seventh decade in rib cross sections of subjects of both sexes. Moore ('55) earlier published separate cross-sectional data indicating continuing growth of the cranial vault through late adulthood, thus indicating that weight-bearing, flexion-stressed bones axe not unique in the apparent property of continuing growth.With cross-sectional data from five populations at hand, and having both longterm and short-term longitudinal data from a single ongoing study population, we have been concerned with three aspects of the problem of continuing bone growth. First, there is the question of such adult growth in various bones throughout the body, weight-bearing, flexion-stressed and otherwise. Second, there is the problem of generalization-whether such bone expansion is population-limited or not and sexspecific or not. Third, there is the problem of confinnation of such continuing growth on an individual basis in order to rule out artifacts of sampling and differential survival.It is the purpose of the present study to explore continuing bone growth in two populations from the United States and AM. J. Pays. ANTHROP., 26: 313-318.three Central American populations, using longitudinal data to further test for individual trends. It is the additional purpose of this study to investigate adult bone growth in both weight-bearing bone and in bone not subject to compression or flexion stress in order to determine whether such mechanical factors play a necessary role in continuing bone growth. METHODS AND MATERIALSThis study is based upon vernier caliper measurements of the second metacarpal on pastero.anterior hand radiographs from five different population samples, one skeletal and four living. 2799 subjects are represented in the cross-sectional study.

No abstract

No abstract

No abstract

No abstract

Additional and extended data on 2726 subjects from Costa Rica, Honduras, Nicaragua and Panama provide confirming evidence for continuing bone expansion of the second metacarpal at midshaft. As shown in 4924 subjects from eight populations, subperiosteal apposition is more rapid in the female than in the male, and accounts for a net increase of 10% in cross-sectional area from age 25 to age 85. Unlike endosteal resorption, which is precipitous in onset, adult subperiosteal gain is continuous from the third through the ninth decades.

The skeletal maturation of 7972 rural children from the six Central American nations, aged one month through 22 years, is evaluated. The results suggest that retardation in skeletal maturation during childhood is significantly greater than during adolescence, while growth in body size shows a progressive delay from infancy through adolescence. In other words, the apparent improvement in skeletal maturation during adolescence is not associated with a n equivalent "catch-up" in body size. Similarly, prolongation of the period of growth does not fully compensate for the slow rate of growth. It is postulated that the small stature in Central America is related to the marked childhood retardation and to the fact that during adolescence, the timing of skeletal maturation is less affected than growth in size.

No abstract