姿势对椎间盘退变影响的实验研究

The Experimental Study of the Postures＇ Effect on the Disc Degeneration

目的 通过建立压力可控型椎间盘退变模型,探讨不同的姿势对椎间盘退变的影响.方法 80只成年大鼠随机分为A,B,C,D 4组,分别模拟人类在站立（A组）、坐位直立（B组）、坐位前屈（C组）3种状态下椎间盘内的压力情况,应用恒定加压装置对第9,10尾椎加压,D组为对照组.A,B,C组每日加压4h,对照组仅在尾椎穿针,不加压;4组分别在7,14d后取标本进行组织学观察,应用免疫组化和阿利新蓝分析测量Ⅱ型胶原纤维和蛋白多糖含量,观察椎间盘退变情况.结果 ①A组、D组类似,椎间盘组织形态、基质胶原和蛋白聚糖（PG）含量和成分无明显变化;②C组椎间盘发生软骨细胞变性、坏死,髓核皱缩,纤维环胶原纤维变性、排列紊乱,软骨终板钙化、断裂,胶原纤维排列紊乱等组织形态学改变.髓核和软骨终板中PG总量和Ⅱ型胶原表达下降（P〈0.05〈0.05）③B组14d时形态学未观察到软骨细胞坏死等退变表现,但Ⅱ型胶原以及PG含量比对照组明显减少（P〈0.05）,退变程度较C组轻.结论 椎间盘承受的压力越大,持续时间越长,退变越明显,因此不同的姿势对椎间盘退变影响不同,其中以坐位前屈时对椎间盘退变影响最大,从而提醒人们在生活工作中注意良好的姿势.

Objective To develop a pressure-control degenerative disc animal model and find the different posture＇effect on the disc degeneration. Methods Eighty mice were divided into 4 groups randomly and each group＇ discs were under the different pressure （ produce by a permanent pressurizing device） simulating the different human posture. Each group was under the different loading simulate human standing（ Group A） ,sitting（ Group B ） ,and sitting flexion（ Group C） position. Group D was the control group without any pressure to the disc. Mice of the A, B, C groups were under the different loading for 4 hours a day. 7 and l4 days later,the mice were sacrificed and histology changes, collagen Ⅱ and proteoglycan（PG） components content were observed to find the degeneration situation of the discs. Results （1）Mice in Group A and Group D were similar and showed no morphology,collagen Ⅱ and PG content changes on intervertebral disc. （2）In group C,the pathological changes of the intervertebral disc including：Spit of the annulus fibrosis,dehydration of pulposus nucleus,derangement of the collagen of the annulus fibrosis, calcification, ossification and separation of the cartilage endplate ; PG content in the pulposus nucleus and the cartilage endplate and the collagen Ⅱ decreased significantly （ P 〈 0.05 ）. （3）In group B, no pathological changes were observed but the collagen Ⅱ and PG content decreased significantly compared to the control group （ P 〈 0.05 ）. Conclusion As the load was larger and the duration was longer, the discs degeneration were more severe. Therefore, the different posture had different effect on the disc and the sitting flexion posture was the most dangerous one that the people should avoid.