重建髋臼前后柱完整性的生物力学研究

The Biomechanics Research of Reconstructed Anterior and Posterior Column of the Acetabulumn

目的 运用平面有限元及光弹实验原理,研究髋臼负重区前后柱骨折后的应力分布,阐明髋关节骨性关节炎产生病理基础和力学机制。方法 建立骶髂关节和髋关节平面有限元模型,模拟单腿站立负重状态,分析髋臼负重区及近负重区在不同骨折类型和位移下的应力分布。结果 髋臼负重区的裂缝型和台阶型骨折局部应力增大;负重区内位移一致的台阶型较裂缝型骨折局部出现应力集中。近负重区较负重区内的骨折所产生的应力小。结论 髋臼负重区骨折应尽可能达到解剖复位,尤以台阶型为著。恢复髋臼前后柱的完整性,可减少负重区的应力集中,减小髋臼病损、延缓关节退变的发生。早期的髋臼重建对后期因髋关节骨性关节炎行人工髋关节置换术提供可靠骨性结构,使手术有更多的选择空间。

Objective Two methods of 2 - D finite element and photoelastic experiment were used to analyze the contact stress changes of forward and back columns acetabulum fracture. The objective was to explain the cause of basic pathology and mechanism of hip joint os-teoarthritis. Methods Two-D finite models of sacroiliac and hip joint were used to test the changing stress and strains under the different kind of fracture,which were in sustaining lord position or near it, when standing by one leg. Results The stress of fractures in sustaining lord position were more hazard than others. The stress in ascended fractures is larger than in wrinkled one under the same position. The stress which near sustaining position have no changes. Conclusion The fractures in sustaining lord position should be reconstructed, especially for ascended fractures. It can reduce the hazard stress in sustaining lord position and make the development of hip joint os-teoarthritis slowly. It can provide convinces for later hip joint replacement surgery.