R Adams Cowley Shock Trauma Center, Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
R Adams Cowley Shock Trauma Center, Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
Injury. 2020 Apr;51(4):850-855. doi: 10.1016/j.injury.2020.02.059. Epub 2020 Feb 11.
To compare clinically important mechanical properties of three techniques used to fix transverse olecranon fractures (Arbeitsgemeinschaft fur Osteosynthesefragen and Orthopaedic Trauma Association class 2U1B1): (1) intramedullary (IM) screw, (2) locking plate, and (3) tension band wire in a realistic loading protocol using a cadaveric model.
Fresh frozen cadaveric transverse olecranon fracture models were fixed with an IM screw (n = 6), a locking plate (n = 6), or a tension band (n = 6). Compression after fixation was recorded using a pressure sensor in the fracture before samples were loaded through the triceps tendon for 500 cycles of 0-500 N, assessing implant survival. The primary outcome measure was compression force before loading. The secondary outcome was frequency of implant failure defined as breakage of the implant itself or fracture gapping >5 mm. Binary outcomes were compared with χ, and continuous variables were compared with unadjusted analysis of variance and a multivariable regression model adjusting for age, sex, dual-energy X-ray absorptiometry T-score, and testing order.
No statistically significant difference was shown in fracture compression between IM screw (mean, 162 N; 95% confidence interval [CI], 27-297 N), locking plate (mean, 125 N; 95% CI, -9-260 N), and tension band (mean, 163 N; 95% CI, 29-298 N) in unadjusted (p = 0.89) and adjusted (p = 0.82) analyses. A 100% implant failure rate was observed with tension band compared with 0% implant failure with IM screw or locking plate (p < 0.01).
We found no statistically significant differences in compression across the fracture site among techniques. We did find a higher risk of implant failure with tension band compared with IM screw and locking plate during cyclic loading in cadaveric bone.
通过尸体模型，在现实的加载方案中比较三种用于固定横断尺骨鹰嘴骨折的技术（ Arbeitsgemeinschaft fur Osteosynthesefragen 和 Orthopaedic Trauma Association 2U1B1 类）的临床重要力学特性：（1）髓内（IM）螺钉，（2）锁定板，（3）张力带钢丝。
用 IM 螺钉（n=6）、锁定板（n=6）或张力带（n=6）固定新鲜冷冻的横断尺骨鹰嘴骨折模型。在样本通过三头肌腱加载 500 次 0-500N 循环之前，使用骨折处的压力传感器记录固定后的压缩力，以评估植入物的存活率。主要观察指标为加载前的压缩力。次要结果是植入物失效的频率，定义为植入物本身断裂或骨折间隙>5mm。二项结果用χ²进行比较，连续变量用未调整方差分析和多变量回归模型进行比较，该模型调整了年龄、性别、双能 X 射线吸收法 T 评分和测试顺序。
在未调整（p=0.89）和调整（p=0.82）分析中，IM 螺钉（平均 162N；95%置信区间 [CI]，27-297N）、锁定板（平均 125N；95% CI，-9-260N）和张力带（平均 163N；95% CI，29-298N）之间，骨折处的压缩差异无统计学意义。与 IM 螺钉或锁定板相比，张力带的植入物完全失效率为 100%，而植入物失效率为 0%（p<0.01）。
我们发现，在尸体骨的循环加载中，各种技术之间的骨折部位的压缩差异没有统计学意义。与 IM 螺钉和锁定板相比，张力带的植入物在循环加载中更容易失效。
