垂直应力影响骨盆环应力分布的实验研究

目的：应用三维光弹力学实验，研究垂直应力对骨盆环应力分布的影响。方法：我敏材料E－51环氧树脂制作人体骨盆三维光弹模型共8具（16个髋关节）。骨盆模型加模型垂直作用力，模型应力冻结，测量和分析骨盆环的应力分布及应力改变。结果：双腿站立及垂直应力下，等色线条纹集中在骶髂关节和髋臼附近，垂直应力主要通过骶髂关节，髂骨弓状线处，髋臼穹顶及骶骨传导，随着垂直应力的增加，骶髂关节，髂骨弓状线处，髋臼穹顶及骶骨等部位的应力明显增大（P＜0．05）；耻骨上支的应力也增大（P＞0．05）。结论：垂直应力作用下，骨盆环的应力分布复杂，骨折易发生在骶髂关节，髂骨，髋臼穹顶骶骨等部位，耻骨上支传导部分垂直应力；治疗垂直不稳定型骨盆骨折时应复位及内固定上述损伤部位。

The Experimental Study and Clinical Application of Effect of the Vertical Stress on the Pelvic Ring

Objective: Our aim was to investigate the biomechanic characteristic of the pelvic ring under the vertical stress by the 3-dimensional photoelastics. Methods: Eight photoelastic pelvic models (16 hip joints) were made with light-sensatory material with hypersensitivity E-51 epoxy resin. The various vertical loading was put on the pelvic models, while the froze stress was performed. We analyzed the distribution and change of pelvic model stresses. Results: With the standing condition of double legs and vertical stresses, the streaks on the pictures of identical color-string were centralized on the sacroiliac joint and the acetabulum. The vertical stresses on the pelvis were transmitted through the sacroilic joint, the arch line of ilium, the dome of acetabulum, and the sacrum. When the vertical stresses on the pelvis increased, the stresses increased significantly on the sacroilic joint, arch line of ilium, the dome of acetabulum, and the sacrum ( P < 0.05 ), but did not change obviously on the pubic superioris ( P > 0.05). Conclusion: With the vertical stresses, the distribution of pelvic stresses is complicated. With the vertical stresses, the fractures occurred easily on the sacroilic joint, arch line of ilium, the dome of acetabulum, and the sacrum. The pubic superioris can transmit the vertical stresses. It is necessary to treat vertically unstable pelvic fractures with replacement and internal fixed the injured pelvic ring.