管状骨增宽牵引成骨组织形态学变化的实验研究

目的 探讨管状骨增宽牵引后新骨形成的变化。方法 在成年山羊的后肢放置2只增宽牵引器。实验组9只术后第8天牵引，对照组3只不牵引。牵引完毕后不同时期，各宰杀3只，评价管状骨增宽牵引后新骨形成的质和量。结果 实验组胫骨平均增宽7．83mm，X射线见牵引间隙逐渐变模糊，暴露侧有骨不连，非暴露侧成骨良好，牵引完毕3个月，未暴露侧新形成板层骨与原来胫骨融为一体，而暴露侧骨不连区为致密纤维组织。结论 管状骨增宽牵引成骨后，两侧牵引间隙成骨不一致，良好的血供，对新骨形成至关重要。

The histomorphological changes of tubular bone following widening distraction osteogenesis

ObjectiveThe purpose of this experimental study was to investigate the histomorphological changes of tubular bone following widening distraction osteogenesis. Methods Twelve Chinese mountain goats were subjected to the study. After the procedure of vertical and horizontal osteotomy, two widening distraction osteogenesis devices were put in each goat's left tibiae. After an 8-day latency period, nine tibiae were widening distracted; another three tibiae served as sham control group. Every three animals from the experimental group were sacrificed in different consolidated periods including 1-month, 2-month, and 3-month. Radiography, tetracycline double labeling, histomorphology, as well as biomechanics were used to evaluate the quality and quantity of new generated bone in different consolidated period after distraction osteogenesis. Results After a distraction period, the average width of the tibiae is increased 7.83mm. From the end of distraction to 3-month after the consolidation period, radiography demonstrated that the distraction gaps gradually became vague. Tetracycline double labeling showed that the double labeling brands were rarely seen in normal cortex bone, but strongly increased in the distracted callus. Mineralization rates (MR) has a significant difference (P<0.05) within distracted callus region compared with control cortex bone. Histomorphological study shows that there was a different result in two sides of vertical distracted gaps. The non-exposure side had a good bone formation, while a non-union of bone occurred at the exposure side. Three months after consolidation period, part of the gap in exposure side was filled with dense connection tissue, whereas the distracted callus had been remodeled and become lamellar bone in non-exposure side. The control group showed normal fracture healing procedure. ConclusionsThere was a different outcome in two sides distraction gaps of tubular bone following widening distraction osteogenesis. A viable and well-perfused soft-tissue envelope in the area of distraction osteogenesis is important for creation of sufficient amount of new bone during distraction osteogenesis.