人造骨修复骨缺损过程的实验研究

EXPERIMENTAL STUDY ON ARTIFICIAL BONE IN REPAIRING BONE DEFECTS

目的了解人造骨修复骨缺损的过程。方法选择健康中国家兔45只,将其左桡骨制成20 mm的骨缺损模型,在左侧桡骨骨缺损处用人造骨移植、钢板螺丝钉固定,右侧做为对照。于术后2、4、6、8、12、16、24周行X线拍片,并取骨缺损处标本切片,观察在骨缺损修复后各个时期的组织形态学变化过程。术后24周测量抗弯强度。结果人造骨植入后2周骨骼残端有少量骨痂形成,与植入材料之间有纤维组织存在,并有少量新骨形成;术后4周骨骼残端与人造骨之间有连续骨痂形成,骨残端成骨活跃,有部分的编织骨出现,植入材料内部有散在的新生骨出现;16周时人造骨与骨残端之间有模糊的密度过渡区,在骨缺损区出现条带状的新生骨;24周骨缺损区有大量的新生骨形成,骨连接基本形成。24周后实验组桡骨带钢板测量平均抗弯强度为(89.98±18.21)N,对照组平均抗弯强度为(88.26±17.54)N,二者无显著性差异(P>0.05)。实验组去除钢板后测量平均抗弯强度为(45.73±9.62)N,与对照组比较有显著性差异(P<0.01)。结论羟基磷灰石人造骨植入骨缺损后其愈合过程与正常骨愈合类似,但其替代过程需要较长时间;用羟基磷灰石人造骨修复骨缺损时一定要有可靠的固定材料,以弥补羟基磷灰石人造强度较差的不足。

Objective To explore the process of repairing bone defects with artificial bones, Methods Models of 20mm bone defect on the left radii were made from 45 rabbits raised in china, and artificial bones were used to repair the defects. Sections of the defects were observed 2,4,6,8,12,16 and 24 weeks later through studying X- rays to get the histomorphological changes in different periods. The anti-bending intensity was measured 24 weeks later. Results A small number of calli formed on the bone stumps two weeks later and fibrous tissues and some new bones began to appear between the artificial bones and the defected ones. Continuous Porisis began by the 4th week,some woven bones appeared, and new bones began to form in the transplanted bones, There appeared some transition area between the artificial bone and the bone stumps, A streak of new bone appeared by 16th week, A large number of new bones formed by the 24th week and bone union formed. The radial average anti-bending intensity was （89, 98 ± 18.2） N in the experimental group, while（88.26 ± 17.54） N in the contrast group（ P 〉0.05）, When the steel plates were removed in the experimental group, the average anti-beMing intensity Was （45,73 ± 9, 62）N, and there existed significant differences between te two groups（ P 〈 0.01 ）, Conclusion Artificial bone made from hydroxyapatite（HA） can produce similar healing effects as normal bones, but this needs more time. In addition, reliable fixing materials must be chosen to make up for the low intensity of HA in repair bone defects.