Hammond James, Ruland Robert, Hogan Christopher, Rose David, Belkoff Stephen
Department of Orthopaedic Surgery, Naval Medical Center Portsmouth, Portsmouth, VA 23703, USA.
J Hand Surg Am. 2012 Dec;37(12):2506-11. doi: 10.1016/j.jhsa.2012.07.025. Epub 2012 Sep 18.
To determine (1) the most distal site at which a tension band construct can maintain bony alignment during dynamic loading of a transverse, length-stable olecranon osteotomy; (2) the location of displacement during cyclical loading; and (3) the ultimate load to failure of the fixation.
We divided 23 non-osteoporotic, fresh-frozen upper extremities into 4 groups. We created transverse osteotomies at 25% of the olecranon surface in group 1, 50% in group II, 75% in group III, and 100% in group IV. We used standard tension band wiring technique to stabilize each osteotomy. We mounted specimens on a biomechanical testing machine at 90° elbow flexion and subjected them to a 150-N sinusoidal load through the triceps tendon at 1 Hz for 500 cycles. An optical motion tracking system synchronized with the testing machine-measured displacement of the osteotomy in any plane. On completion of cycling, we loaded specimens at 1 mm/s until 2-mm displacement occurred. We analyzed data to determine the effect of the location of the osteotomy on load to failure and location of displacement.
Of the 23 specimens, 21 survived the cycling process. The 2 specimens that failed were both in group II (50%). Excluding these 2 specimens, the average displacement at the 3 virtual points was less than 1.05 mm in all 4 osteotomy groups. There were no statistical differences between groups. Load to failure was 476, 361, 511, and 610 N for groups I to IV, respectively. Differences between groups were not statistically significant.
The stability achieved with tension band wire fixation did not vary with the location of the osteotomy.
Based on this biomechanical study, when it is properly executed, tension band wire fixation may be used effectively for transverse, length-stable fractures of the olecranon regardless of the amount of articular surface included on the proximal fragment.
确定（1）在横行、长度稳定的鹰嘴截骨术动态加载过程中，张力带结构能够维持骨对线的最远端位置；（2）周期性加载过程中的位移位置；（3）固定的极限破坏载荷。
我们将23个非骨质疏松的新鲜冷冻上肢分为4组。在第1组中，于鹰嘴表面25%处制作横行截骨术；第2组为50%；第3组为75%；第4组为100%。我们采用标准张力带钢丝技术稳定每个截骨术。将标本置于生物力学测试机上，使肘关节屈曲90°，并通过肱三头肌腱以1Hz的频率施加150N的正弦载荷，持续500个循环。一个与测试机同步的光学运动跟踪系统测量截骨术在任何平面的位移。循环结束后，以1mm/s的速度加载标本，直至出现2mm的位移。我们分析数据以确定截骨术位置对破坏载荷和位移位置的影响。
23个标本中，21个在循环过程中存活。2个失败的标本均在第2组（50%）。排除这2个标本后，所有4个截骨术组中3个虚拟点的平均位移均小于1.05mm。各组之间无统计学差异。第1至4组的破坏载荷分别为476、361、511和610N。各组之间的差异无统计学意义。
张力带钢丝固定所实现的稳定性并不随截骨术位置的改变而变化。
基于这项生物力学研究，当操作适当时，张力带钢丝固定可有效地用于横行、长度稳定的鹰嘴骨折，而无论近端骨折块包含的关节面数量多少。
