Dudle Alice, Gugler Yvan, Satir Osman Berk, Gewiess Jan, Klein Stefan, Zysset Philippe
ARTORG Center for Biomedical Engineering Research, University of Bern, Switzerland.
Department of Orthopaedic Surgery and Traumatology, Inselspital, Bern University Hospital, Switzerland.
Bone Rep. 2024 Jul 2;22:101786. doi: 10.1016/j.bonr.2024.101786. eCollection 2024 Sep.
Aging is associated with an increased risk of fragility fractures at the hip, resulting from a loss of bone mass. While this loss is typically reported as a decreased mean areal bone mineral density (aBMD) in the proximal femur or the femoral neck, its evolution is spatially inhomogeneous, which might also contribute to the increased risk of fractures. Yet, little is known about the evolution of BMD distribution and cortical thickness with age in the proximal femur. We propose a 3D spatio-temporal atlas of the proximal femur to identify regions with high BMD losses and cortical thinning. The atlas is based on 532 post-mortem QCT scans from donors aged 20 to 94, including 179 female subjects. A point cloud with anatomically corresponding positions was defined for each femur based on a personalized coordinate system. The evolution of BMD and cortical thickness was computed as a multiple linear regression with age and BMI, for female and male subjects separately. The average BMD decrease with age was significant in all subregions for both sexes but higher in females. High BMD losses were observed in the superior and middle neck regions, in the medial part of the head, and in the trochanteric trabecular bone. BMD was well preserved in the inferior neck and, for males, in cortical regions. In both sexes, the cortical thickness decreased significantly in the superior and posterior neck cortex and increased significantly in the inferior neck. Higher BMI was associated with increased BMD in the inferior neck and medial shaft cortex, as well as with increased cortical thickness in all neck and shaft regions for both sexes. The spatio-temporal atlas showed the evolution of BMD distribution and cortical thickness in the proximal femur, with high losses in typical fracture locations, such as the femoral neck and pertrochanteric regions.
衰老与髋部脆性骨折风险增加相关，这是由骨量流失所致。虽然这种流失通常表现为股骨近端或股骨颈平均骨面积密度（aBMD）降低，但其变化在空间上是不均匀的，这也可能导致骨折风险增加。然而，关于股骨近端骨密度分布和皮质厚度随年龄的变化情况，人们知之甚少。我们提出了一个股骨近端的三维时空图谱，以识别骨密度损失高和皮质变薄的区域。该图谱基于532例年龄在20至94岁的捐赠者的死后定量CT扫描，其中包括179名女性受试者。基于个性化坐标系为每根股骨定义了具有解剖学对应位置的点云。分别针对女性和男性受试者，将骨密度和皮质厚度的变化计算为年龄和体重指数的多元线性回归。两性所有亚区域的骨密度随年龄的平均降低均显著，但女性更高。在上颈部和中颈部区域、股骨头内侧部分以及转子间小梁骨中观察到骨密度大量流失。下颈部以及男性的皮质区域骨密度保存良好。在两性中，上颈部和后颈部皮质的皮质厚度显著降低，下颈部则显著增加。较高的体重指数与下颈部和内侧骨干皮质的骨密度增加相关，也与两性所有颈部和骨干区域的皮质厚度增加相关。时空图谱显示了股骨近端骨密度分布和皮质厚度的变化，在典型骨折部位，如股骨颈和转子周围区域有大量骨量流失。
