Azari Fahimeh, Colyn William, Bellemans Johan, Scheys Lennart, van Lenthe G H
Biomechanics Section, Mechanical Engineering, KU Leuven, Leuven, Belgium.
Department of Orthopedic Surgery, AZ Turnhout, Turnhout, Belgium.
JBMR Plus. 2024 Feb 1;8(4):ziae014. doi: 10.1093/jbmrpl/ziae014. eCollection 2024 Apr.
Knee osteoarthritis is a whole joint disease highlighting the coupling of cartilage and bone adaptations. However, the structural properties of the subchondral bone plate (SBP) and underlying subchondral trabecular bone (STB) in the femoral compartment have received less attention compared to the tibial side. Furthermore, how the properties in the femoral compartment relate to those in the corresponding tibial site is unknown. Therefore, this study aimed to quantify the structural bone and cartilage morphology in the femoral compartment and investigate its association with those of the tibial plateau. Specifically, tibial plateaus and femoral condyles were retrieved from 28 patients with end-stage knee-osteoarthritis (OA) and varus deformity. The medial condyle of tibial plateaus and the distal part of the medial femoral condyles were micro-CT scanned (20.1 μm/voxel). Cartilage thickness (Cart.Th), SBP, and STB microarchitecture were quantified. Significant ( < <.001; 0.79 ≤ ≤ 0.97) correlations with a relative difference within 10% were found between the medial side of the femoral and tibial compartments. The highest correlations were found for SBP porosity ( = 0.97, mean absolute difference of 0.50%, and mean relative difference of 9.41%) and Cart.Th ( = 0.96, mean absolute difference of 0.18 mm, and relative difference of 7.08%). The lowest correlation was found for trabecular thickness ( = 0.79, mean absolute difference of 21.07 μm, and mean relative difference of 5.17%) and trabecular number ( = 0.79, mean absolute difference of 0.18 mm-, and relative difference of 5.02%). These findings suggest that the distal femur is affected by OA in a similar way as the proximal tibia. Given that bone adaptation is a response to local mechanical forces, our results suggest that varus deformity similarly affects the stress distribution of the medial tibial plateau and the medial distal femur.
膝关节骨关节炎是一种强调软骨与骨适应性耦合的全关节疾病。然而，与胫骨侧相比，股骨髁间区的软骨下骨板（SBP）和下方的软骨下小梁骨（STB）的结构特性受到的关注较少。此外，股骨髁间区的特性与相应胫骨部位的特性之间的关系尚不清楚。因此，本研究旨在量化股骨髁间区的骨结构和软骨形态，并研究其与胫骨平台的相关性。具体而言，从28例终末期膝关节骨关节炎（OA）和内翻畸形患者中获取胫骨平台和股骨髁。对胫骨平台的内侧髁和股骨内侧髁的远端进行显微CT扫描（体素为20.1μm）。量化软骨厚度（Cart.Th）、SBP和STB微结构。在股骨和胫骨内侧髁间区之间发现了显著相关性（< <.001；0.79≤ ≤0.97），相对差异在10%以内。SBP孔隙率（ = 0.97，平均绝对差异为0.50%，平均相对差异为9.41%）和Cart.Th（ = 0.96，平均绝对差异为0.18mm，相对差异为7.08%）的相关性最高。小梁厚度（ = 0.79，平均绝对差异为21.07μm，平均相对差异为5.17%）和小梁数量（ = 0.79，平均绝对差异为0.18mm-，相对差异为5.02%）相关性最低。这些发现表明，股骨远端受OA影响的方式与胫骨近端相似。鉴于骨适应性是对局部机械力的一种反应，我们的结果表明，内翻畸形同样会影响胫骨内侧平台和股骨内侧远端的应力分布。
