脊柱内固定导致邻近关节突关节退变的实验研究（超微结构观察）

目的 研究脊柱内固定对邻近运动节段关节突关节的超微结构影响。方法 制作山羊多节段脊柱内固定的动物模型，对近固定头侧２个邻近关节突关节进行扫描电镜及透镜电镜的观察。结果 固定３组邻近关节突关节出现了软骨基质较严重的破坏，而软骨细胞呈现出活跃的分泌功能；固定６个月软骨基质的破坏进一步加剧，而软骨细胞也出现较严重的退变表现。在３月及６月组中，头部２个邻近关节突关节的退变程度基本一致。结论 脊柱内固定导致

AN EXPERIMENTAL STUDY ON THE DEGENERATION OF ADJACENT FACET JOINTS INDUCED BY SPINAL FIXATION (ULTRASTRUCTURE INVESTIGATION)

Objective To study the ultrastructural changes in the adjacent facet joints induced by spinal fixation. Metheds Transmission and scanning electronic microscopies were performed on the cartilage of 2 adjacent facet joints cephalic to the multi-segment spinal fixation in 10 sheep models at 3 months and 6 months postoperatively.Results The ultrastructure observation at 3 months showed minor lesions in the matrix of cartilage. The chondrocytes were hyperactive in synthetic and secretory function.At 6 months, the lesions in the matrix were aggravated and most of chondrocytes were degenerative.The first and second adjacent facet joints cephalic to the spinal fixation were found to have similar morphological evidences of degeneration in the whole course of observation. Conclusion The degeneration of the adjacent facet joints induced by spimal fixation is mainly attributed to the high stress environment of the adjacent segments.