桥形钢板的研制与实验研究

Experimental study of bridge plate with polyethylene washer

目的 为克服接骨板固定后骨吸收和骨结构紊乱 ,设计一种加垫的桥形钢板 ,通过动物实验比较新型钢板和普通加压钢板对骨折愈合和骨结构变化的影响。方法 30只新西兰兔在双侧胫腓骨连接处截骨 ,右侧用直条钢板固定 ,左侧用有垫桥形钢板固定 ,在中央和两边螺孔内放置降解速度不同的高分子垫圈。术后 5、10、15周分三批处死动物后测量骨折和螺钉间内、外径和骨皮质厚度并进行光镜和荧光观察。结果 对照侧骨皮质变薄 ,骨髓腔扩大较实验组明显 ;组织学发现 ,实验组骨痂出现早 ,骨质吸收少 ,骨折局部改进快。结论 加垫桥形钢板可以减少钢板对骨的应力遮挡效应 ,有利于骨折愈合。

Objective In order to decrease stress shielding effect including osteoporosis and resorption of the bone after plate fixation,bridge plate padded with different absorption rates ultrahigh molecular polyethylene washers in its screw holes was designed and used in the fracture site. Methods A comparative study was done on thirty adult New Zealand rabbits in this experiment. Ordinary stress stainless steel plate and bridge plate padded with washer were fixed respectively on mid shaft of the tibia. The rabbits were sacrificed at 5,10 and 15 weeks. The fixed bone segments of both tibiae were removed for radiological and histological examination. Results The results showed that the severity of osteoporosis and resorption in experiment group were less than that in the control. Conclusion The bridge plate padded washers in its screw holes can reduce bone resorption caused by stress shielding and made the fracture union quickly.