股骨粗隆间骨折滑动加压外固定器的设计及生物力学评价

Biomechanical Test and Study of Sliding Load External Fixator in Fixture of Femoral Intertrochanteric Fracture

目的设计制作股骨粗隆间骨折滑动加压外固定器,并对其生物力学性能进行评价。方法取5对成人新鲜股骨标本,造成AO分型A1·1型股骨粗隆间骨折模型。试验组用滑动加压外固定器固定,对照组用单侧成角外固定器固定。实验分为骨折端张开角度的测试、骨断端应力分布的测试、骨断端接触面积的计算。结果①张开角度:各载荷条件下试验组张开角度明显小于对照组;②骨断端的应力分布:试验组包括张力侧各点均为压应力,而对照组在外侧4个测试点为拉应力;③骨折端接触面积:相同载荷下骨折端接触面积试验组较对照组大47·1%。结论滑动加压外固定器的各项生物力学性能均优于普通外固定器。

Objective To design and make the sliding load external fixator （SLEF） and evaluate its biomechanical properties. Methods Five pairs of fresher adult femur specimens were prepared, and the model of A1.1 （AO classification） fracture was established. For the experimental group the specimens were fixed with the sliding load external fixation （SLEF）, while for the contorl group the specimens were fixed with traditional one arm external fixation. It was conducted on the electronic almighty experimental plane. Experimental tests were divided into the opened angle, the stress distribution in the edge of fracture, the fracture - contact area. Results （1） Opened angle： under every load, the opened angle of the experimental group was significantly smaller than control group. （2）The stress distribution in the edge of fracture： the outer side four points were pulled stress, but the experimental group including tension side were all pressure stress. （3）Fracture-contact area： the experimental group was 47.1% bigger than the control group under the same load. Conclusion The performance of the biological mechanics about sliding load external fixator （SLEF） is superior to the ordinary fixed devices.