We hypothesized that subjects with hyperostosis frontalis interna (HFI), which represents local, endocranial thickening of the frontal bone, would express extra-calvarial manifestations of this condition. Therefore, we compared femoral bone mineral density, geometry, and microarchitecture of males and females with HFI to those without this condition as well as between males and females with HFI. The sample was taken from human donor cadavers, 38 males (19 with and 19 without HFI) and 34 females (17 with and 17 without HFI) that were age-matched within the same sex. The specimens of femoral bones were scanned using microcomputed tomography and dual-energy X-ray absorptiometry (DXA). Parameters of hip structure analysis (HSA) were calculated from data derived from DXA scans. Females with HFI had increased cortical bone volume fraction and their cortical bone was less porous compared to females without HFI. Males with HFI showed microarchitectural differences only with the trabecular bone. They had increased bone volume fraction and decreased trabecular separation compared to males without HFI, although with borderline significance. These microarchitectural changes did not have significant impact on femoral geometry and bone mineral density. The same, still unknown etiological factor behind HFI might be inducing changes at the level of bone microarchitecture at a remote skeletal site (femoral bone), in both sexes. These alterations still do not have the magnitude to induce obvious, straightforward overall increase of bone mineral density measured by DXA. HFI could be a systemic phenomenon that affects both males and females in a similar manner.

我们假设患有额骨增生症（HFI）（代表额骨的局部，颅内增厚）的受试者会表达这种情况的颅外表现。因此，我们比较了患有HFI的男性和女性与没有HFI的男性和女性之间的股骨矿物质密度，几何形状和微结构。该样本取自同性别内年龄匹配的38位男性（有HFI的人和19位没有HFI的人）和34位女性（有HFI的人和17位没有HFI的人）。使用微计算机断层扫描和双能X射线吸收法（DXA）扫描股骨标本。髋部结构分析（HSA）的参数是根据DXA扫描得出的数据计算得出的。与没有HFI的女性相比，患有HFI的女性的皮质骨体积分数增加，并且其皮质骨的孔少。患有HFI的男性仅在小梁骨上表现出微结构差异。与没有HFI的男性相比，他们的骨体积分数增加了，而小梁的分离减少了，尽管具有临界意义。这些微结构改变对股骨的几何形状和骨矿物质密度没有显着影响。HFI背后相同但仍未知的病因可能是在男女两性的远处骨骼部位（股骨）引起的骨骼微结构水平的变化。这些改变仍然没有引起DXA测量的骨矿物质密度明显，直接的总体增加的幅度。