John J, Wagner W W, Kuiper J H
Robert Jones Agnes Hunt Orthopaedic Hospital, Gobowen, Oswestry, UK.
Int Orthop. 2007 Oct;31(5):703-7. doi: 10.1007/s00264-006-0238-0. Epub 2006 Oct 11.
Tension-band wiring is commonly used to treat transverse patella fractures. The most common configuration has parallel Kirschner (K) wires and a stainless steel wire loop placed in a vertically oriented figure of eight. Early mobilisation is important but can cause detrimental displacement at the fracture site. A wooden model of a transversely fractured patella was used to compare different fixation constructs. The fracture was fixed using two K wires and a stainless steel wire loop. One or two wire twists were used, placed either arbitrarily or at corners of the loop. The loop was oriented either vertically or horizontally. Interfragmentary compression at the point of wire breakage and permanent displacement on cyclic loading was measured for each construct. Placement of the figure of eight in a horizontal orientation with two wire twists at the corner improved interfragmentary compression by 63% (p<0.05, Tukey post hoc test). On cyclic loading, all constructs with vertical figure of eight but none with a horizontal construct failed (p=0.01; Fisher's exact test). Permanent fracture displacement after cyclic loading was 67% lower with horizontal figure of eight constructs (p<0.05; t test). Placing wire twists at the corner and a horizontal placement of figure of eight improves stability of the construct.
张力带钢丝固定术常用于治疗髌骨横行骨折。最常见的构型是平行克氏针（K 针）和置于垂直“8”字形的不锈钢丝环。早期活动很重要，但可能导致骨折部位有害的移位。使用一个髌骨横行骨折的木制模型来比较不同的固定结构。骨折采用两根 K 针和一个不锈钢丝环进行固定。使用一到两个钢丝扭结，扭结位置随意或位于环的角部。环的方向为垂直或水平。测量每种结构在钢丝断裂点的骨折块间压缩以及循环加载时的永久移位。将“8”字形置于水平方向并在角部有两个钢丝扭结可使骨折块间压缩提高 63%（p<0.05，Tukey 事后检验）。在循环加载时，所有垂直“8”字形结构均失败，但水平结构无一失败（p = 0.01；Fisher 精确检验）。水平“8”字形结构在循环加载后的永久骨折移位降低了 67%（p<0.05；t 检验）。在角部放置钢丝扭结和将“8”字形水平放置可提高结构的稳定性。
