Anatomical Institute, University of Basel, Basel, Switzerland.
Division of Macroscopic and Clinical Anatomy, Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria.
J Anat. 2023 Sep;243(3):475-485. doi: 10.1111/joa.13857. Epub 2023 Mar 9.
The sacroiliac auricular surface has a variable morphology and size. The impact of such variations on subchondral mineralization distribution has not been investigated. Sixty-nine datasets were subjected to CT-osteoabsorptiometry for the qualitative visualization of chronic loading conditions of the subchondral bone plate using color-mapped densitograms based on Hounsfield Units in CT. Auricular surface morphologies were classified into three types based on posterior angle size: Type 1: >160°, Type 2: 130-160° and Type 3: <130°. Auricular surface size was categorized based on the mean value (15.4 cm ) separating the group into 'small' and 'large' joint surfaces. Subchondral bone density patterns were qualitatively classified into four color patterns: two marginal patterns (M1 and M2) and two non-marginal patterns (N1 and N2) and each iliac and sacral surface was subsequently categorized. 'Marginal' meant that 60-70% of the surface was less mineralized compared with the highly dense regions and vice versa for the 'non-marginal' patterns. M1 had anterior border mineralization and M2 had mineralization scattered around the borders. N1 had mineralization spread over the whole superior region, N2 had mineralization spread over the superior and anterior regions. Auricular surface area averaged 15.4 ± 3.6 cm , with a tendency for males to have larger joint surfaces. Type 2 was the most common (75%) and type 3 the least common morphology (9%). M1 was the most common pattern (62% of surfaces) by sex (males 60%, females 64%) with the anterior border as the densest region in all three morphologies. Sacra have a majority of surfaces with patterns from the marginal group (98%). Ilia have mineralization concentrated at the anterior border (patterns M1 and N2 combined: 83%). Load distribution differences related to auricular surface morphology seems to have little effect on long-term stress-related bone adaptation visualized with CT-osteoabsorptiometry. Higher iliac side mineralization was observed in larger joint surfaces and age-related morphomechanical size alterations were seen in males.
耳状面的形态和大小存在差异。但是目前尚未研究这些差异对软骨下矿化分布的影响。本研究共纳入 69 例数据集，对其进行 CT 骨吸收测量，通过 CT 单位的彩色密度图对软骨下骨板的慢性负荷情况进行定性可视化。根据后角大小，将耳状面形态分为 3 种类型：1 型>160°，2 型 130-160°，3 型<130°。根据耳状面平均大小（15.4cm），将关节面分为“小”和“大”关节面。将软骨下骨密度模式分为 4 种颜色模式：2 种边缘模式（M1 和 M2）和 2 种非边缘模式（N1 和 N2），然后对每个髂骨和骶骨表面进行分类。“边缘”表示与高密度区相比，60-70%的表面矿化程度较低，反之亦然。M1 有前缘矿化，M2 有边缘矿化。N1 整个上区有矿化，N2 有上、前区矿化。耳状面面积平均为 15.4±3.6cm，男性关节面较大。2 型最常见（75%），3 型最不常见（9%）。M1 是最常见的模式（62%的表面），男女两性中，前缘是最致密的区域。M1 在所有 3 种形态中都是最常见的模式（男性 60%，女性 64%）。骶骨的大部分表面均为边缘组的模式（98%）。髂骨的矿化集中在前缘（M1 和 N2 两种模式结合：83%）。与耳状面形态相关的负荷分布差异似乎对 CT 骨吸收测量显示的长期与压力相关的骨骼适应性影响不大。较大的关节面有较高的髂骨侧矿化，男性可见与年龄相关的形态力学尺寸变化。
