AO Research Institute, AO Foundation, Clavadelerstrasse 8, 7270 Davos, Switzerland.
BMC Musculoskelet Disord. 2010 Aug 4;11:172. doi: 10.1186/1471-2474-11-172.
In the face of costly fixation hardware with varying performance for treatment of distal humeral fractures, a novel technique (U-Frame) is proposed using conventional implants in a 180 degrees plate arrangement. In this in-vitro study the biomechanical stability of this method was compared with the established technique which utilizes angular stable locking compression plates (LCP) in a 90 degrees configuration.
An unstable distal 3-part fracture (AO 13-C2.3) was created in eight pairs of human cadaveric humeri. All bone pairs were operated with either the "Frame" technique, where two parallel plates are distally interconnected, or with the LCP technique. The specimens were cyclically loaded in simulated flexion and extension of the arm until failure of the construct occurred. Motion of all fragments was tracked by means of optical motion capturing. Construct stiffness and cycles to failure were identified for all specimens.
Compared to the LCP constructs, the "Frame" technique revealed significant higher construct stiffness in extension of the arm (P = 0.01). The stiffness in flexion was not significantly different (P = 0.16). Number of cycles to failure was found significantly larger for the "Frame" technique (P = 0.01).
In an in-vitro context the proposed method offers enhanced biomechanical stability and at the same time significantly reduces implant costs.
面对治疗肱骨远端骨折的各种昂贵固定硬件，我们提出了一种新颖的技术（U 型框架），即使用常规植入物以 180 度板排列。在这项体外研究中，我们将这种方法的生物力学稳定性与现有的技术进行了比较，后者使用角度稳定的锁定加压钢板（LCP）以 90 度配置。
在 8 对人体尸体肱骨中创建了不稳定的远端 3 部分骨折（AO 13-C2.3）。所有骨对均采用“框架”技术或 LCP 技术进行操作，其中“框架”技术是将两块平行的板在远端相互连接。通过光学运动捕捉，对所有标本进行模拟手臂屈伸的循环加载，直到结构失效。
与 LCP 结构相比，“框架”技术在手臂伸展时显示出明显更高的结构刚度（P = 0.01）。在弯曲时，刚度没有明显差异（P = 0.16）。“框架”技术的失效循环数明显更大（P = 0.01）。
在体外环境下，所提出的方法提供了增强的生物力学稳定性，同时显著降低了植入物的成本。
