Pastor Tatjana, Zderic Ivan, Beeres Frank J P, Helmy Nader, Richards R Geoff, Kriechling Philipp, Drenchev Ludmil, Skulev Hristo K, Gueorguiev Boyko, Pastor Torsten
AO Research Institute Davos, Davos, Switzerland.
Department of Orthopaedics and Traumatology, Bürgerspital Solothurn, Solothurn, Switzerland.
J Orthop Res. 2025 Mar;43(3):473-482. doi: 10.1002/jor.26020. Epub 2024 Nov 25.
Helical plates used for proximal humeral shaft fracture fixation avoid the radial nerve distally as compared to straight plates. To investigate in a human cadaveric model the biomechanical competence of straight lateral plates versus 45° helical plates used for fixation of proximal comminuted humeral shaft fractures, eight pairs of human cadaveric humeri were instrumented using either a long straight PHILOS plate (Group 1) or a 45° helical plate (Group 2) for treatment of an unstable proximal humeral shaft fracture. All specimens were tested under non-destructive quasi-static loading in axial compression, internal and external rotation, and bending in four directions. Subsequently, progressively increasing cyclic loading in internal rotation was applied until failure and interfragmentary movements were monitored by motion tracking. Axial displacement (mm) was 3.13 ± 0.31 in Group 1 and 2.60 ± 0.42 in Group 2, p = 0.015. Flexion/extension deformation (°) in Group 1 and Group 2 was 0.56 ± 0.42 and 0.43 ± 0.23, p = 0.551. Varus/valgus deformation (°) was 6.39 ± 0.44 in Group 1 and 5.13 ± 0.87 in Group 2, p = 0.012. Shear (mm) and torsional (°) displacement were 5.36 ± 0.76 and 17.75 ± 1.06 in Group 1, and 5.03 ± 0.46 and 16.79 ± 1.36 in Group 2, p ≥ 0.090. Cycles to catastrophic failure were 10000 ± 1401 in Group 1 and 9082 ± 1933 in Group 2, p = 0.708. From a biomechanical perspective, 45° helical plating is associated with lower axial and varus/valgus displacement under axial loading and demonstrates comparable resistance to failure versus straight plating. Therefore, 45° helical plates can be considered as a valid alternative to straight plates for treatment of proximal humeral shaft fractures.
与直板相比，用于肱骨近端骨干骨折固定的螺旋板在远端可避免桡神经。为了在人体尸体模型中研究用于固定肱骨近端粉碎性骨干骨折的直板与45°螺旋板的生物力学性能，使用长直板PHILOS板（第1组）或45°螺旋板（第2组）对八对人体尸体肱骨进行器械固定，以治疗不稳定的肱骨近端骨干骨折。所有标本均在轴向压缩、内旋和外旋以及四个方向弯曲的非破坏性准静态载荷下进行测试。随后，在内旋中施加逐渐增加的循环载荷直至失效，并通过运动跟踪监测骨折块间的运动。第1组的轴向位移（mm）为3.13±0.31，第2组为2.60±0.42，p = 0.015。第1组和第2组的屈伸变形（°）分别为0.56±0.42和0.43±0.23，p = 0.551。内翻/外翻变形（°）在第1组为6.39±0.44，在第2组为5.13±0.87，p = 0.012。第1组的剪切（mm）和扭转（°）位移分别为5.36±0.76和17.75±1.06，第2组为5.03±0.46和16.79±1.36，p≥0.090。灾难性失效的循环次数在第1组为10000±1401，在第2组为9082±1933，p = 0.708。从生物力学角度来看，45°螺旋钢板在轴向载荷下轴向和内翻/外翻位移较低，并且与直板相比具有相当的抗失效能力。因此，45°螺旋板可被视为治疗肱骨近端骨干骨折的直板的有效替代方案。
