Colyn W, Azari F, Bellemans J, van Lenthe G H, Scheys L
Orthopaedic Department, AZ Turnhout, Steenweg Op Merksplas 44, 2300 Turnhout,
Eur Cell Mater. 2023 Feb 20;45:60-71. doi: 10.22203/eCM.v045a05.
Recent studies highlighted the crucial contribution of subchondral bone to OA development. Yet, only limited data have been reported on the relation between alteration to cartilage morphology, structural properties of the subchondral bone plate (SBP) and underlying subchondral trabecular bone (STB). Furthermore, the relationship between the morphometry of the cartilage and bone in the tibial plateau and the OA-induced changes in the joint's mechanical axis remains unexplored. Therefore, a visualisation and quantification of cartilage and subchondral bone microstructure in the medial tibial plateau was performed. End stage knee-OA patients with varus alignment and scheduled for total knee arthroplasty (TKA) underwent preoperative fulllength radiography to measure the hip-knee-ankle angle (HKA) and the mechanical-axis deviation (MAD). 18 tibial plateaux were μ-CT scanned (20.1 μm/voxel). Cartilage thickness, SBP, and STB microarchitecture were quantified in 10 volumes of interest (VOIs) in each medial tibial plateau. Significant differences (p < 0.001) were found for cartilage thickness, SBP, and STB microarchitecture parameters among the VOIs. Closer to the mechanical axis, cartilage thickness was consistently smaller, while SBP thickness and STB bone volume fraction (BV/TV) were higher. Moreover, trabeculae were also more superior-inferiorly oriented, i.e. perpendicular to the transverse plane of the tibial plateau. As cartilage and subchondral bone changes reflect responses to local mechanical loading patterns in the joint, the results suggested that region-specific subchondral bone adaptations were related to the degree of varus deformity. More specifically, subchondral sclerosis appeared to be most pronounced closer to the mechanical axis of the knee.
近期研究突显了软骨下骨在骨关节炎（OA）发展过程中的关键作用。然而，关于软骨形态改变、软骨下骨板（SBP）及下方软骨下小梁骨（STB）的结构特性之间的关系，仅有有限的数据报道。此外，胫骨平台软骨与骨的形态测量学和OA引起的关节机械轴变化之间的关系仍未得到探索。因此，对内侧胫骨平台的软骨和软骨下骨微观结构进行了可视化和量化研究。对患有内翻畸形且计划进行全膝关节置换术（TKA）的终末期膝OA患者进行术前全长X线摄影，以测量髋-膝-踝角（HKA）和机械轴偏差（MAD）。对18个胫骨平台进行了μ-CT扫描（体素为20.1μm）。在每个内侧胫骨平台的10个感兴趣体积（VOI）中对软骨厚度、SBP和STB微结构进行量化。在各VOI之间，软骨厚度、SBP和STB微结构参数存在显著差异（p<0.001）。更靠近机械轴处，软骨厚度始终较小，而SBP厚度和STB骨体积分数（BV/TV）较高。此外，小梁在上下方向上的排列也更多，即垂直于胫骨平台的横平面。由于软骨和软骨下骨的变化反映了对关节局部机械负荷模式的反应，结果表明特定区域的软骨下骨适应性与内翻畸形程度有关。更具体地说，软骨下硬化似乎在更靠近膝关节机械轴处最为明显。
