齿接触半环抱钢板对骨折处皮质骨血供的影响

【目的】研究齿接触半环抱钢板对骨折局部钢板下皮质骨血供的影响。【方法】成年新西兰大白兔30只,体质量2.8～3.5 kg。双侧胫骨中段横形截骨,右侧用齿接触半环抱钢板内固定(实验组),左侧用同等型号的AO传统钢板内固定(对照组)。术后2、4、6周各10只处死后行墨汁灌注微血管造影术。而后获取骨标本,用手术显微镜观察钢板下皮质骨内微血管的形态,并进行钢板下全层皮质骨纵向照片,每批照片随机抽取30张,用全自动图像数字分析系统(video image digital analysis system,VIDAS)分析钢板下皮质骨内微血管面积分数。【结果】①钢板下皮质骨内微血管形态观察:术后2周,对照组钢板下皮质骨出现大面积缺血区,并持续到术后6周;术后2周,实验组钢板下出现较小范围的缺血区,但微血管走行及分布紊乱,到术后6周,缺血区基本消失,微血管走行基本恢复正常。②钢板下皮质骨内微血管面积分数分析:术后2、4、6周,实验组分别为对照组的1.42、1.96和2.43倍,差异具有统计学意义(P<0.05)。【结论】齿接触半环抱钢板能够保护钢板下皮质骨血供,有利于骨折愈合。

The Tooth Contact Half Cycle Steel Plate Internal Fixation on Cortical Bone Blood Supply at Fracture Site

[Objective] To study the influence of the tooth contact half cycle (TCC) steel plate on cortical bone blood supply at the fracture site. [Methods] 30 adult New Zealand rabbits, weighed from 2. 8 - 3. 5 kg,were used in this experiment. After transverse osteotomy of middle shaft of both tibiae, internal fixation with TCC-steel plate was done in the right tibiae (experimental group) and the similar pattern AO conventional steel plate in the left (control group). Each 10 rabbits were killed and microan-giography was used to do respectively at 2,4 and 6 weeks after surgery. Bone samples were acquired aimed to observe the microvessel morphology of the cortical bone and to take the photographs of microcir-culation of the cortical bone under operating microscope . 30 films randomly drawn from each batch photographs at 2,4 and 6 weeks after surgery were used to analyse the image surface fraction change in micro-circulation of the cortical bone beneath the TCC - steel plate and the AO conventional steel plate with video image analysis system (VIDAS) software. [Results] CD The microvessel morphology of the cortical bone observation: on the control group, a large area ischemia zone of the cortical bone beneath the steel plate was seen at 2 weeks after operation and not disappeared until 6 weeks after operation. In the experimental group, a small area ischemia zone was found, but the distribution of microvessel was disorder; however, at 6 weeks after operation, ischemia zone was almost disappeared and the distribution of microvessel almost restored to normal. (2) The microvascular image surface fraction analyses: the results of the experimental group were 1. 42,1. 96,2. 43-fold as much as that of the control group respectively at 2,4 and 6 weeks after surgery. Statistical difference existed between the two groups ( P < 0. 05). [Conclusion ] The TCC-steel plate can preserve the cortical bone blood supplies beneath the steel plate and improve healing of the fracture.