大鼠腰椎亚脱位模型节段活动范围减小的研究

目的:观察大鼠腰椎亚脱位动物模型基本特性:节段活动范围减小。方法:将108只350～450g雄性SD大鼠随机分为实验组(单纯固定组、旋转固定组)和假手术组。再将各组按固定时间分为2、4、8和12周4个亚组。单纯固定组和旋转固定组分别植入外部连接固定系统进行造模,假手术组仅行手术干预。在各连接期结束时,X线片观察3组造模节段椎体后缘沿线夹角;脊柱刚度测试系统检测单纯固定组和旋转固定组刚度。结果:影像学检测结果显示,实验组大鼠椎体后缘所成的锐角(posterior body angle,PBA)变化呈逐渐减小趋势;而且,各连接期结束时,单纯固定组与旋转固定组间PBA变化差异无统计学意义(P>0.05),实验组与假手术组间PBA变化差异有统计学意义(P<0.05)。刚度检测结果显示实验组大鼠脊柱造模节段刚度随连接时间的延长而增加,2组之间刚度比较差异无统计学意义(P>0.05)。结论:外部连接固定系统诱导的大鼠腰椎亚脱位模型,可有效导致大鼠造模节段脊椎生物力学特性的变化,即节段活动范围减小,且此种变化与时间相关。

Study on hypomobility of motion segment of rats with lumbar subluxation model

Objective:To observe the basic characteristics of rats with subluxation,which was hypomobility of motion. Methods:One hundred and eight male SD rats (weighted,350 to 450 g) were randomly divided into experimental group(simple fixation and rotatory fixation) and sham operation group. Each group was subdivided into four groups,including 2,4,8 and 12 weeks sub-groups. Simple fixation and rotatory fixation group were modeled by implanting external linked fixation system; Sham operation group was dealed with operation intervention. At the end of connection,X-ray films was used to observe posterier body angle(PBA);Spinal stiffness system for stiffness in simple fixation group and rotatory fixation group. Results:Radiographic results showed that variation of PBA n experimental groups tended to decrease;and there was no significant difference between simple fixation group and rotatory fixation group at the end of linking time(P>0.05). But there was significant difference between the experimental group and sham operation group(P<0.05). The degree of stiffness showed that the stiffness in experimental group increased with the linking time,but no meaning between groups(P>0.05). Conclusion:Rats with subluxation induced by external linked fixation system can effectively change biomechanical characteristics of spine,reduced the motion with linking time.