Markus Heinecke, Stefan Schwan, Immanuel Ries, Kumar Jayakumar Ram, Filippo Migliorini, Thomas Mendel
Chair of Orthopedics of Jena University Hospital, Campus Eisenberg, German Center for Orthopedics, Jena University Hospital, Klosterlausnitzer Strasse 81, 07607, Eisenberg, Germany.
Fraunhofer Institute for Microstructure of Materials and Systems IMWS, Walter-Hülse-Strasse 1, 06120, Halle (Saale), Germany.
Sci Rep. 2025 Jul 25;15(1):27146. doi: 10.1038/s41598-025-11174-9.
The incidence of periprosthetic femoral fractures has increased in recent years. Osteosynthetic stabilisation is challenging, particularly for UCS IV.3-C fractures. Lateral plate osteosynthesis is the gold standard; however, it allows excessive vibration, leading to plate breakage. Orthogonal double plate osteosynthesis has been established but requires considerable intraoperative dissection of the anterior extensor muscle. This work aims to analyse newly developed plate designs that demonstrate adequate vibration behaviour, which, in turn, promotes callus healing and causes less soft tissue trauma than the plate constructs used to date. A hip prosthesis geometry and a parameterised volume geometry of a UCS IV.3-C type periprosthetic femur fracture were simulated to generate a finite element model. Additionally, three alternative design studies were developed to optimise an LCP®, and the various constructs were then investigated using a finite element model concerning comparative stress and deformation under static and dynamic loading and their influence on fracture gap expansion. Isolated lateral plate osteosynthesis (V1) and double plate osteosynthesis (V2) served as references. The alternative plate designs include a ventral frame at the fracture level (V3) or spanning the length of the lateral LCP® (V4). The fifth variant is a fulcrum support attached to the existing LCP® at the fracture level (V5). Compared with V1, V3 and V4 yielded comparable results, presenting greater stiffness and increased survival. The functionality of V5 shows nearly identical outcomes to those of V1. Here, failure with plastic deformation is already observed under static loading, which does not occur with V2 even under dynamic loading, thus representing the most stable construct, albeit one that does not permit adequate vibration behaviour. For V3 and V4, optimal strain behaviour in the fracture gap is also evident after load application. Alternative implant design variants with an additional anterior frame lead to reduced deformation and failure of fixation in UCS IV.3-C periprosthetic femur fractures. In addition to double plate osteosynthesis, alternative plate constructs exhibit optimal strain behaviour conducive to callus fracture healing. Furthermore, the selected designs decrease the required dissection of the quadriceps muscle.
近年来，人工关节周围股骨骨折的发生率有所增加。骨合成稳定术具有挑战性，尤其是对于UCS IV.3 - C型骨折。外侧钢板骨合成术是金标准；然而，它会产生过度振动，导致钢板断裂。正交双钢板骨合成术已确立，但需要对股前伸肌进行大量术中解剖。这项工作旨在分析新开发的钢板设计，这些设计表现出足够的振动特性，进而促进骨痂愈合，并且比迄今使用的钢板结构造成的软组织创伤更小。模拟了髋关节假体几何形状和UCS IV.3 - C型人工关节周围股骨骨折的参数化体积几何形状，以生成有限元模型。此外，开展了三项替代设计研究以优化锁定加压钢板（LCP®），然后使用有限元模型研究各种结构在静态和动态载荷下的比较应力和变形及其对骨折间隙扩展的影响。孤立的外侧钢板骨合成术（V1）和双钢板骨合成术（V2）作为对照。替代钢板设计包括在骨折水平处的腹侧框架（V3）或跨越外侧LCP®长度的框架（V4）。第五种变体是在骨折水平处连接到现有LCP®的支点支撑（V5）。与V1相比，V3和V4产生了可比的结果，表现出更大的刚度和更高的存活率。V5的功能显示出与V1几乎相同的结果。在此，即使在静态载荷下也已观察到塑性变形失效，而V2即使在动态载荷下也不会出现这种情况，因此V2代表最稳定的结构，尽管它不具备足够的振动特性。对于V3和V（4），加载后骨折间隙中的最佳应变行为也很明显。带有附加前框架的替代植入物设计变体可减少UCS IV.3 - C型人工关节周围股骨骨折中的变形和固定失败。除双钢板骨合成术外，替代钢板结构表现出有利于骨痂骨折愈合的最佳应变行为。此外，所选设计减少了股四头肌所需的解剖。
