Continuum-level finite element models (FEMs) of the humerus offer the ability to evaluate joint replacement designs preclinically; however, experimental validation of these models is critical to ensure accuracy. The objective of the current study was to quantify experimental full-field strain magnitudes within osteoarthritic (OA) humeral heads by combining mechanical loading with volumetric microCT imaging and digital volume correlation (DVC). The experimental data was used to evaluate the accuracy of corresponding FEMs. Six OA humeral head osteotomies were harvested from patients being treated with total shoulder arthroplasty and mechanical testing was performed within a microCT scanner. MicroCT images (33.5 µm isotropic voxels) were obtained in a pre- and post-loaded state and BoneDVC was used to quantify full-field experimental strains (≈ 1 mm nodal spacing, accuracy = 351 µstrain, precision = 518 µstrain). Continuum-level FEMs with two types of boundary conditions (BCs) were simulated: DVC-driven and force-driven. Accuracy of the FEMs was found to be sensitive to the BC simulated with better agreement found with the use of DVC-driven BCs (slope = 0.83, r² = 0.80) compared to force-driven BCs (slope = 0.22, r² = 0.12). This study quantified mechanical strain distributions within OA trabecular bone and demonstrated the importance of BCs to ensure the accuracy of predictions generated by corresponding FEMs.

肱骨的连续体级有限元模型 (FEM) 提供了在临床前评估关节置换设计的能力；然而，这些模型的实验验证对于确保准确性至关重要。本研究的目的是通过将机械载荷与体积 microCT 成像和数字体积相关 (DVC) 相结合来量化骨关节炎 (OA) 肱骨头内的实验全场应变幅度。实验数据用于评估相应 FEM 的准确性。从接受全肩关节置换术治疗的患者中采集 6 例 OA 肱骨头截骨，并在 microCT 扫描仪内进行机械测试。MicroCT 图像 (33.5 µm 各向同性体素）在预加载和后加载状态下获得，BoneDVC 用于量化全场实验应变（≈ 1 mm 节点间距，精度 = 351 µ应变，精度 = 518 µ应变）。模拟了具有两种边界条件 (BC) 的连续级 FEM：DVC 驱动和力驱动。与力驱动的 BC（斜率 = 0.22，r ² = 0.12 ）相比，FEM 的准确性被发现对模拟的 BC 很敏感，使用 DVC 驱动的 BC（斜率 = 0.83，r ² = 0.80）发现更好的一致性）。本研究量化了 OA 骨小梁内的机械应变分布，并证明了 BC 对确保相应 FEM 生成的预测准确性的重要性。