Department of Industrial Engineering, Alma Mater Studiorum-University of Bologna, Bologna, Italy.
Medical Technology Lab, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy.
PLoS One. 2022 Sep 9;17(9):e0272529. doi: 10.1371/journal.pone.0272529. eCollection 2022.
Pathologies such as cancer metastasis and osteoporosis strongly affect the mechanical properties of the vertebral bone and increase the risk of fragility fractures. The prediction of the fracture risk with a patient-specific model, directly generated from the diagnostic images of the patient, could help the clinician in the choice of the correct therapy to follow. But before such models can be used to support any clinical decision, their credibility must be demonstrated through verification, validation, and uncertainty quantification. In this study we describe a procedure for the generation of such patient-specific finite element models and present a first validation of the kinematics of the spine segment. Quantitative computed tomography images of a cadaveric lumbar spine segment presenting vertebral metastatic lesions were used to generate the model. The applied boundary conditions replicated a specific experimental test where the spine segment was loaded in compression-flexion. Model predictions in terms of vertebral surface displacements were compared against the full-field experimental displacements measured with Digital Image Correlation. A good agreement was obtained from the local comparison between experimental data and simulation results (R2 > 0.9 and RMSE% <8%). In conclusion, this work demonstrates the possibility to apply the developed modelling pipeline to predict the displacement field of human spine segment under physiological loading conditions, which is a first fundamental step in the credibility assessment of these clinical decision-support technology.
病理性改变，如癌症转移和骨质疏松，会严重影响椎骨的机械性能，并增加脆性骨折的风险。通过直接从患者的诊断图像生成的患者特异性模型来预测骨折风险，可以帮助临床医生选择正确的治疗方法。但是，在这些模型可以用于支持任何临床决策之前，必须通过验证、确认和不确定性量化来证明其可信度。在本研究中，我们描述了一种生成此类患者特异性有限元模型的方法，并对脊柱节段的运动学进行了初步验证。使用具有椎体转移性病变的尸体腰椎节段的定量计算机断层扫描图像来生成模型。施加的边界条件复制了特定的实验测试，其中脊柱节段在压缩-弯曲状态下加载。通过数字图像相关测量的完整场实验位移与模型预测的椎体表面位移进行比较。实验数据和模拟结果之间的局部比较得到了很好的一致性（R2 > 0.9，RMSE% <8%）。总之，这项工作表明可以应用所开发的建模流程来预测人体脊柱节段在生理载荷条件下的位移场，这是评估这些临床决策支持技术可信度的第一步。
