Aging of metacarpal density at midshaft and proximal end

Aging of bone density of the second metacarpal at midshaft (compact bone) and the proximal end (trabecular bone) was compared in 114 men and 115 women, 30–98 years of age. The microdensitometric (MD) pattern of the bone at both sites, area (Σ GS) and midheight (GSmid), were measured in standardized aluminun equivalents (SAE). In both sexes, Σ GS and GSmid showed a greater deviation at the proximal end than at midshaft. There was a significant correlation between both sites for each parameter. Pattern area was significantly greater at the proximal end than at midshaft( P ⩽ 0.01), but the relation was reversed for GSmid. At both sites, Σ GS and GSmid decreased gradually with age in both sexes, especially after 69 years in women. Each parameter showed a significant negative linear regression with age at both sites in women and at midshaft in men. In both sexes, the slope of the regression curve of Σ GS with age was significantly steeper at the proximal end than at midshaft. In women, the estimated rate of decline was 0.90% and 0.56% for Σ GS, and 1.20% and 0.73% for GSmid per year at the proximal end and midshaft, respectively. The bone density loss with age may be slightly greater in trabecular than in compact bone. © 1995 Wiley‐Liss, Inc.