Terjesen T, Apalset K
Department of Orthopaedic Surgery, Trondheim University Hospital, Norway.
J Orthop Res. 1988;6(2):293-9. doi: 10.1002/jor.1100060218.
In order to throw some light on the controversial issue of the optimal stiffness in fracture fixation, the effects on bone healing of rabbit tibial osteotomies fixed by plates with four different degrees of stiffness were studied. The least stiff plate was made of glass fiber-reinforced epoxy; the other three were made of stainless steel. The median bending stiffness in vitro of tibial osteotomies fixed with the various plates were 13%, 17%, 61%, and 74%, related to the stiffness of intact tibiae. Transverse midshaft unilateral tibial osteotomies were fixed by the various plates, and the animals were killed after 6 weeks. The amount of periosteal callus was inversely related to the stiffness of the plates. A marked trend toward decreased strength and stiffness occurred in tibiae where the most rigid plate was used, compared with the values of those with the less rigid plates. This indicates that the stress-protecting effect of very stiff plates begins early in the healing period and is pronounced even at 6 weeks and that a steel plate of lower stiffness is more appropriate for bone healing. However, too flexible plates involve increased risk of redislocation and mechanical failure.
为了阐明骨折固定中最佳刚度这一有争议的问题，研究了用四种不同刚度的钢板固定兔胫骨截骨术对骨愈合的影响。最软的钢板由玻璃纤维增强环氧树脂制成；另外三种由不锈钢制成。用不同钢板固定的胫骨截骨术在体外的中位弯曲刚度分别为完整胫骨刚度的13%、17%、61%和74%。用不同钢板固定横断胫骨中段单侧截骨术，6周后处死动物。骨膜骨痂量与钢板刚度呈负相关。与使用较软钢板的胫骨相比，使用最硬钢板的胫骨出现了强度和刚度降低的明显趋势。这表明非常硬的钢板的应力保护作用在愈合早期就开始了，甚至在6周时就很明显，并且较低刚度的钢板更适合骨愈合。然而，过于柔韧的钢板会增加再脱位和机械故障的风险。
