Department of Mechanical Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab 140001, India.
Center for Biomedical Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab 140001, India.
J Biomech. 2021 Jun 23;123:110495. doi: 10.1016/j.jbiomech.2021.110495. Epub 2021 May 5.
Type-2 diabetic (T2D) and osteoporosis (OP) suffered patients are more prone to fragile fracture though the nature of alteration in areal bone mineral density (aBMD) in these two cases are completely different. Therefore, it becomes crucial to compare the effect of T2D and OP on alteration in mechanical and structural properties of femoral trabecular bone. This study investigated the effect of T2D, OP, and osteopenia on bone structural and mechanical properties using micro-CT, nanoindentation and compression test. Further, a nanoscale finite element model (FEM) was developed to predict the cause of alteration in mechanical properties. Finally, a damage-based FEM was proposed to predict the pathological related alteration of bone's mechanical response. The obtained results demonstrated that the T2D group had lower volume fraction (-18.25%, p = 0.023), young's modulus (-23.47%, p = 0.124), apparent modulus (-37.15%, p = 0.02), and toughness (-40%, p = 0.001) than the osteoporosis group. The damage-based FE results were found in good agreement with the compression experiment results for all three pathological conditions. Also, nanoscale FEM results demonstrated that the elastic and failure properties of mineralised collagen fibril decreases with increase in crystal size. This study reveals that T2D patients are more prone to fragile fracture in comparison to OP and osteopenia patients. Also, the proposed damage-based FEM can help to predict the risk of fragility fracture for different pathological conditions.
2 型糖尿病（T2D）和骨质疏松症（OP）患者更容易发生脆性骨折，尽管这两种情况的骨密度（aBMD）面积变化的性质完全不同。因此，比较 T2D 和 OP 对股骨小梁骨机械和结构性能变化的影响至关重要。本研究使用 micro-CT、纳米压痕和压缩试验研究了 T2D、OP 和低骨量对骨结构和机械性能的影响。此外，开发了纳米尺度有限元模型（FEM）来预测机械性能变化的原因。最后，提出了基于损伤的 FEM 来预测与骨骼机械响应相关的病理变化。结果表明，T2D 组的体积分数（-18.25%，p=0.023）、杨氏模量（-23.47%，p=0.124）、表观模量（-37.15%，p=0.02）和韧性（-40%，p=0.001）均低于骨质疏松症组。基于损伤的 FE 结果与所有三种病理条件下的压缩实验结果吻合良好。此外，纳米尺度 FEM 结果表明，矿化胶原纤维的弹性和失效特性随晶体尺寸的增加而降低。本研究表明，与 OP 和低骨量患者相比，T2D 患者更容易发生脆性骨折。此外，提出的基于损伤的 FEM 可以帮助预测不同病理条件下的脆性骨折风险。
