Onder Yilmaz, Bulut Tugrul, Eroglu Osman Nuri, Ciklacandir Samet, Isler Yalcin
Department of Orthopaedics and Traumatology, Izmir Katip Celebi University, Ataturk Training and Research Hospital, Izmir, Türkiye.
Department of Biomedical Engineering, Izmir Katip Celebi University Faculty of Engineering and Architecture, Izmir, Türkiye.
Acta Orthop Traumatol Turc. 2024 Dec 31;58(6):313-317. doi: 10.5152/j.aott.2024.24076.
The aim of this study was to evaluate whether the locking femoral neck plate (LFNP) can be an alternative fixation method to the cannulated screws with a medial buttress plate. For this purpose, we compared biomechanically the LFNP and cannulated screws with or without a medial buttress plate in Pauwels type 3 femoral neck fractures.
A vertical fracture model was created at an 80-degree angle to the femoral neck in 28 synthetic bone models. The models were randomly divided into 4 groups, each containing 7 bones each. The bone fracture models were fixed with 3 parallel cannulated screws in group 1, 3 parallel cannulated screws combined with a medial buttress plate in group 2, LFNP in group 3, LFNP combined with a medial buttress plate in group 4. The stability of the specimens was tested biomechanically at a 7° valgus inclination to simulate normal 2-legged weight-bearing through an anatomical femur. The forces corresponding to 0.5 mm, 1 mm, 1.5 mm, and 2 mm displacement and failure loads were calculated in all groups.
The axial load values corresponding to 4 di!erent fracture displacements and the failure load values of the groups were compared, group 1 was significantly weaker (P < .05 for each) while group 4 was significantly stronger (P < .05 for each) compared to the other groups. There was no statistically significant di!erence between group 2 and group 3 (P > .05 for each).
The results of this biomechanical study showed that the LFNP fixation system provided su"cient biomechanical stability for unstable Pauwels type 3 femoral neck fractures. The biomechanical performance of LFNP was similar to that of cannulated screws with medial buttress plate and better than that of cannulated screws alone. This suggests that LFNP can be a promising stable alternative fixation method to cannulated screws with a medial buttress plate in unstable femoral neck fractures.
本研究旨在评估锁定股骨颈钢板（LFNP）是否可作为带内侧支撑钢板的空心螺钉的替代固定方法。为此，我们在生物力学方面比较了LFNP与带或不带内侧支撑钢板的空心螺钉在 Pauwels 3型股骨颈骨折中的应用。
在28个合成骨模型中创建与股骨颈呈80度角的垂直骨折模型。将模型随机分为4组，每组7块骨。第1组用3枚平行空心螺钉固定骨折模型，第2组用3枚平行空心螺钉联合内侧支撑钢板固定，第3组用LFNP固定，第4组用LFNP联合内侧支撑钢板固定。通过解剖股骨以7°外翻倾斜模拟正常双腿负重，对标本的稳定性进行生物力学测试。计算所有组在0.5 mm、1 mm、1.5 mm和2 mm位移及破坏载荷时对应的力。
比较了4种不同骨折位移对应的轴向载荷值和各组的破坏载荷值，与其他组相比，第1组明显较弱（各比较P <.05），而第4组明显较强（各比较P <.05）。第2组和第3组之间无统计学显著差异（各比较P >.05）。
本生物力学研究结果表明，LFNP固定系统为不稳定的 Pauwels 3型股骨颈骨折提供了足够的生物力学稳定性。LFNP的生物力学性能与带内侧支撑钢板的空心螺钉相似，且优于单纯空心螺钉。这表明在不稳定股骨颈骨折中，LFNP可成为带内侧支撑钢板的空心螺钉一种有前景的稳定替代固定方法。
