Division of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway; Norwegian Armed Forces Joint Medical Services, Oslo, Norway.
Division of Orthopaedic Surgery, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
J Shoulder Elbow Surg. 2020 Jun;29(6):1242-1248. doi: 10.1016/j.jse.2020.01.079. Epub 2020 Mar 3.
Tension band wiring (TBW) is the standard method for treating transverse olecranon fractures, but high rates of complications and reoperations have been reported. Plate fixation (PF) with locking screws has been introduced as an alternative method that may retain the fracture reduction better with a higher load to failure.
Twenty paired cadaveric elbows were used. All soft tissues except for the triceps tendon were removed. A standardized transverse fracture was created, and each pair was allocated randomly to TBW or PF with locking screws. The triceps tendon was mounted to the materials testing machine with the elbow in 90° of flexion. Construct stiffness was compared 3 times. Then, the elbows underwent a chair lift-off test by loading the triceps tendon to 300 N for 500 cycles. Finally, a load-to-failure test was performed, and failure mechanism was recorded.
The construct stiffness of PF was higher in the first of 3 measurements. No difference was observed in the cyclic test or in load to failure. Hardware failure was the failure mechanism in 8 of 10 TBW constructs, and all failures occurred directly under the twists of the metal wire. Hardware failure was the cause of failure in only 1 elbow in the PF group (P < .01).
There was no difference in fracture displacement following fixation with TBW and PF with locking screws in transverse olecranon fractures. However, assessment of the mode of hardware failure identified the metal cerclage twist as the weakest link in the TBW construct.
张力带钢丝（TBW）是治疗横断性尺骨鹰嘴骨折的标准方法，但据报道，其并发症和再次手术率较高。带锁定螺钉的钢板固定（PF）已被引入作为一种替代方法，它可能通过更高的失效载荷更好地保持骨折复位。
使用 20 对尸体肘部。除去除三头肌腱以外的所有软组织。创建标准化的横断骨折，然后将每对随机分配至 TBW 或带锁定螺钉的 PF。将三头肌腱安装到材料试验机上，使肘部处于 90°的弯曲状态。比较 3 次构造刚度。然后，通过向三头肌腱施加 300N 的力进行 500 次循环，使肘部进行椅上升测试。最后，进行失效载荷测试，并记录失效机制。
PF 的结构刚度在前 3 次测量中的第一次更高。在循环测试或失效载荷中没有差异。TBW 构建的 8 个中有 10 个出现硬件失效，所有失效都直接发生在金属丝扭曲的地方。PF 组中只有 1 个肘部出现硬件失效（P<0.01）。
在横断性尺骨鹰嘴骨折中，TBW 和 PF 固定后的骨折移位没有差异。然而，对硬件失效模式的评估表明，金属环扎丝扭曲是 TBW 构建的最薄弱环节。
