Age-Related Changes and Regional Variations in Three-Dimensional Microstructural Properties of Male Proximal Femoral Trabecular Bone

Abstract

"Purpose: The purpose of this study was therefore to explore regional variations in the 3D microstructure of trabecular bone in human proximal femur, with respect to aging. Materials and Methods: A total of 162 trabecular bone cores were obtained from six regions (femoral head, superior and inferior regions of the neck, and superior/middle and inferior regions of the trochanter) of twenty-seven normal femora of Korean male cadaver donors, aged 40-90 years. These specimens were scanned using high-resolution micro-computed tomography (micro-CT). The following 3D microstructural parameters were calculated: bone volume fraction (BV/TV), trabecular thickness (Tb.Th), separation (Tb.Sp) and number (Tb.N), structure model index (SMI) and degree of anisotropy (DOA). Results: The results showed that the trabecular microstructure changed significantly with age, as well as varied from different regions of the proximal femur. There was a significant decrease in bone volume fraction and an almost identical decrease in trabecular thickness associated with aging at any region. Regional analysis demonstrated a significant difference not only in BV/TV, Tb.Th, Tb.Sp, Tb.N, DOA between superior and inferior neck, but also difference in BV/TV, Tb.Sp, Tb.N, SMI, DOA between superior and inferior trochanter. Conclusions: Age-related changes in bone loss and trabecular microstructure within the male proximal femur are not uniform in this Korean cadaveric population. As a result of mechanical and age-related adaptation, significant regional variations in microstructural properties of trabecular bone are likely to be an important factor affecting the mechanical properties of the proximal femur. "