Regional variations in trabecular morphological features of femoral head of patients with proximal femoral fractures

The regional microstructural variations in femoral head from proximal femoral fracture patients were investigated. Micro-CT scanning was performed on seven femoral heads from proximal femoral fracture patients. Each femoral head was divided into three regions according to the trabecular orientation from the fovea of femoral head to the femoral neck. Eight three-dimensional trabecular cube models were reconstructed from each region. A total of 154 trabecular cubic models were reconstructed because the corresponding areas for 14 cubic models were damaged during the surgeries. Eight trabecular morphological parameters were measured and analyzed, namely, trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), specific bone surface (BS/BV), bone volume fraction (BV/TV), structural model index (SMI), degree of anisotropy (DA), trabecular pattern factor (Tb.Pf), and trabecular number (Tb.N). Bivariate correlation analyses were performed for all morphological parameters. One-way ANOVA tests were performed to analyze the differences of each parameter among three regions. Post-hoc multiple comparisons (Student-Newman-Keuls method) were performed to analyze the morphological difference between two regions. Trabecular bone of proximal femoral fracture patients significantly degenerated in all regions of femoral heads. BV/TV was statistically correlated with Tb.Th, Tb.Sp, BS/BV, Tb.Pf, and Tb.N (. p < 0.05). Statistical differences in morphological parameters were observed between regions (. p < 0.05). The trabecular strength in the middle regions was significantly higher than that in other regions because of the relationships between morphological parameters and mechanical parameters. Trabeculae in the medial region were more uniform and stable along each direction than those in the lateral region. Most trabeculae in the lateral region only grew along the weight-bearing direction, and those along the other directions degenerated significantly. This study provides detailed trabecular morphological information on fractured femoral heads, as well as references for the prevention of high fracture risk in the elderly.