Šafran J, Pavlacký T, Marcián P, Herůfek R, Veselý R
Brno University of Technology, Brno, Czech Republic.
Masaryk University, Faculty of Medicine, Brno, Czech Republic.
J Orthop Surg Res. 2025 Jul 28;20(1):712. doi: 10.1186/s13018-025-06031-4.
This study investigated the biomechanical behavior of four different screw configurations used to fix comminuted proximal ulna fractures with a locking compression plate (LCP), via a detailed finite element model based on realistic anatomical geometry. The model incorporated realistic anatomical geometry including both cortical and cancellous bone, soft tissue constraints, and loading conditions representing the physiological self-weight of the forearm, with the humerus fixed at its proximal end. The stress distribution on the plate, strain intensity within the bone tissue, and interfragmentary motion (IFM) between fracture fragments were evaluated for each configuration. The results indicate that all the tested configurations provide adequate stability under normal loading conditions, with no risk of material failure. However, excessive stress concentrations were observed in specific screw regions depending on the configuration, particularly when proximal screws anchoring the olecranon (e.g. screws 2 and 3 in Variant 3) were omitted. Strain analysis revealed moderate physiological bone loading across variants, whereas IFM assessment highlighted the importance of securing the coronoid and apical fragments to prevent compromised healing. These findings suggest that a specific reductions in osteosynthetic material, such as omitting certain diaphyseal screws while maintaining crucial olecranon and coronoid fixation, may provide sufficient fracture stabilisation under the modelled conditions, potentially minimising implant-related complications. This modelling approach offers a valuable tool for preclinical assessment of osteosynthesis strategies and supports future comparative research on fixation methods with varying biomechanical properties.
本研究通过一个基于真实解剖几何结构的详细有限元模型，研究了四种不同螺钉配置用于使用锁定加压钢板（LCP）固定粉碎性尺骨近端骨折的生物力学行为。该模型纳入了包括皮质骨和松质骨在内的真实解剖几何结构、软组织约束以及代表前臂生理自重的加载条件，肱骨在其近端固定。对每种配置评估了钢板上的应力分布、骨组织内的应变强度以及骨折碎片之间的骨折块间运动（IFM）。结果表明，所有测试配置在正常加载条件下均提供了足够的稳定性，没有材料失效的风险。然而，根据配置的不同，在特定螺钉区域观察到了过度的应力集中，特别是当锚固鹰嘴的近端螺钉（例如变体3中的螺钉2和3）被省略时。应变分析显示各变体间骨的生理加载适中，而IFM评估突出了固定冠突和根尖碎片以防止愈合受损的重要性。这些发现表明，在模拟条件下，特定的骨合成材料减少，例如在保持关键的鹰嘴和冠突固定的同时省略某些骨干螺钉，可能提供足够的骨折稳定性，潜在地减少与植入物相关并发症。这种建模方法为骨合成策略的临床前评估提供了一个有价值的工具，并支持未来对具有不同生物力学特性的固定方法的比较研究。
