软骨终板钙化在椎间盘退变过程中的作用机理

Study on the Mechanism of Cartilage End-plate Calcification on Dise Degeneration

目的 :研究椎体软骨终板钙化在椎间盘退变过程中的作用。方法 :2 0只新西兰兔随机分为造模与对照组 2组 ,每组再分 3个月和 8个月 2个观察亚组。切除造模组动物颈棘上、棘间韧带及分离颈椎后旁两侧肌肉 ,造成颈椎力学上的失衡而诱导兔颈椎间盘退行性改变。在术后 3个月和 8个月时分别处死动物 ,取颈椎间盘组织 ,行病理学检查在形态学上评定颈椎间盘退变程度 ,测定不同退变程度椎间盘软骨终板钙化层厚度。结果 :退变程度较轻或基本正常的颈椎间盘 ,软骨终板结构良好 ,潮标清晰 ;退变程度较重的颈椎间盘 ,软骨终板发生明显纤维化 ,潮标前移 ,钙化软骨和软骨下骨板增厚。软骨终板钙化层厚度与椎间盘退变程度呈非常明显的相关性。结论 :颈椎软骨终板的不断钙化和骨化导致颈椎间盘营养发生障碍可能是启动颈椎间盘退变的关键因素。

Objective:To study the mechanism of the cartilage end plate calcification on intervertebral disc degeneration.Methods:In experiment,20 white New Zealand rabbits were used and divided into two groups:control group and model group.Each group consisted of two subgroup:3 months group and 8 months group.An experimental model of the cervical disc degeneration in the rabbits was established by resection of the cervical supraspinous and interspinous ligaments and detachment of the posterior paravertebral muscles from the cervical vertebrae.Mechanical instability in the cervical spine elicited by this surgical intervention accelerated the process of intervertebral disc degeneration.The degrees of intervertebral disc degeneration were graded in morphology;and the thickness of the calcified layer of the cartilage end plate was measured in each degenerated cervical disc.Results:In less severely degenerative cervical disc,morphology of cartilage end plate showed nearly normal construction,and tidemark was clear.In severely degenerative disc,its matrix and cells showed fibrosis,tidemark advanced forwardly,and calcified cartilage thickened.There exists a positive correlation between the thickness of the calcified layer of the cartilage end plate and the degree in cervical disl coninues to calcify and ossify result in of the cervical disc degeneration.Conclusion:The cartilage end plate and the degree of the cervical disc degeneration.nutrition supply impediment,which is key factor that initiates cervical disc degeneration.