Varga Peter, Inzana Jason A, Schwiedrzik Jakob, Zysset Philippe K, Gueorguiev Boyko, Blauth Michael, Windolf Markus
AO Research Institute Davos, Switzerland.
AO Research Institute Davos, Switzerland.
Clin Biomech (Bristol). 2017 May;44:7-13. doi: 10.1016/j.clinbiomech.2017.03.001. Epub 2017 Mar 2.
High incidence and increased mortality related to secondary, contralateral proximal femoral fractures may justify invasive prophylactic augmentation that reinforces the osteoporotic proximal femur to reduce fracture risk. Bone cement-based approaches (femoroplasty) may deliver the required strengthening effect; however, the significant variation in the results of previous studies calls for a systematic analysis and optimization of this method. Our hypothesis was that efficient generalized augmentation strategies can be identified via computational optimization.
This study investigated, by means of finite element analysis, the effect of cement location and volume on the biomechanical properties of fifteen proximal femora in sideways fall. Novel cement cloud locations were developed using the principles of bone remodeling and compared to the "single central" location that was previously reported to be optimal.
The new augmentation strategies provided significantly greater biomechanical benefits compared to the "single central" cement location. Augmenting with approximately 12ml of cement in the newly identified location achieved increases of 11% in stiffness, 64% in yield force, 156% in yield energy and 59% in maximum force, on average, compared to the non-augmented state. The weaker bones experienced a greater biomechanical benefit from augmentation than stronger bones. The effect of cement volume on the biomechanical properties was approximately linear. Results of the "single central" model showed good agreement with previous experimental studies.
These findings indicate enhanced potential of cement-based prophylactic augmentation using the newly developed cementing strategy. Future studies should determine the required level of strengthening and confirm these numerical results experimentally.
与继发性对侧近端股骨骨折相关的高发病率和死亡率增加，可能使侵入性预防性增强治疗成为合理选择，这种治疗可强化骨质疏松的近端股骨以降低骨折风险。基于骨水泥的方法（股骨成形术）可能产生所需的强化效果；然而，先前研究结果的显著差异要求对该方法进行系统分析和优化。我们的假设是，可通过计算优化确定有效的通用增强策略。
本研究通过有限元分析，研究了骨水泥位置和体积对15例近端股骨在侧方跌倒时生物力学性能的影响。利用骨重塑原理开发了新的骨水泥分布位置，并与先前报道的最佳“单一中心”位置进行比较。
与“单一中心”骨水泥位置相比，新的增强策略提供了显著更大的生物力学益处。与未增强状态相比，在新确定的位置用约12毫升骨水泥进行增强，平均刚度增加11%，屈服力增加64%，屈服能量增加156%，最大力增加59%。较弱的骨骼从增强中获得的生物力学益处比较强的骨骼更大。骨水泥体积对生物力学性能的影响近似呈线性。“单一中心”模型的结果与先前的实验研究结果吻合良好。
这些发现表明，使用新开发的骨水泥注入策略进行基于骨水泥的预防性增强具有更大潜力。未来的研究应确定所需的强化水平，并通过实验证实这些数值结果。
