ZESBO - Centre for Research on Musculoskeletal Systems, Leipzig University, Leipzig, Germany; Institute of Anatomy, Leipzig University, Leipzig, Germany.
ZESBO - Centre for Research on Musculoskeletal Systems, Leipzig University, Leipzig, Germany; Institute of Anatomy, Leipzig University, Leipzig, Germany.
Clin Biomech (Bristol). 2023 May;105:105984. doi: 10.1016/j.clinbiomech.2023.105984. Epub 2023 May 4.
Complex proximal humerus fractures place high demands on osteosynthetic treatment. In some cases, double plating has already been used to increase primary stability of the osteosynthesis. This approach was advanced in the present study by developing an additive plate for the sulcus bicipitalis. To demonstrate the superior primary stability of the newly developed plate osteosynthesis, a biomechanical comparison against a conventional locking plate with an additional calcar screw was performed.
Ten pairs of cadaveric humeri were treated proximally with a locking plate (PENTA plate small fragment, INTERCUS). Each had a two-part fracture model with a fracture gap of 10 mm. All right humeri were treated with an additive novel plate that extends along the bicipital sulcus and encircles the lesser tuberosity proximally. First, the specimens were loaded sinusoidally at 250 N in 20° abduction for 5000 cycles. Afterwards quasi-static loading until failure was applied.
The movement at the fracture gap due to the cyclic loading occurred mainly as rotation around the z-axis, corresponding to a tilt medially and distally. The double plate osteosynthesis reduces the rotation by approximately 39%. For all load cycles observed, except 5000 cycles, medial and distal rotation of the head was significantly reduced by the double plate. The failure loads showed no significant differences between the groups.
In the tested scenario under cyclic loading, the novel double plate osteosynthesis showed a significant superiority of primary stability over the conventional treatment with one locking plate. Furthermore, the study showed the advantages of cyclic load application over quasi-static load application until failure.
复杂的肱骨近端骨折对骨合成治疗有很高的要求。在某些情况下，已经使用双钢板来增加骨合成的初始稳定性。在本研究中，通过为二头肌沟开发附加钢板，对这种方法进行了改进。为了证明新开发的钢板骨合成的初始稳定性更好，与附加骺螺钉的常规锁定钢板进行了生物力学比较。
用锁定钢板（PENTA 小片段板，INTERCUS）对 10 对 cadaveric 肱骨近端进行治疗。每个肱骨都有一个两部分骨折模型，骨折间隙为 10mm。所有右侧肱骨均用新型附加钢板治疗，该钢板沿二头肌沟延伸并在近端环绕小结节。首先，以 250N 的正弦波在 20°外展下加载 5000 个循环。然后施加准静态直至失效的载荷。
由于循环加载导致骨折间隙的运动主要是围绕 z 轴的旋转，对应于内侧和远端的倾斜。双钢板骨合成将旋转减少了约 39%。除了 5000 个循环外，对于观察到的所有负载循环，双钢板显著减少了头部的内侧和远端旋转。两组的失效载荷没有显著差异。
在循环加载测试场景中，新型双钢板骨合成在初始稳定性方面明显优于传统的单锁定钢板治疗。此外，该研究还表明了循环载荷应用相对于直至失效的准静态载荷应用的优势。
