可生物降解聚-DL-乳酸腰椎间融合器的设计及生物力学研究  

Design and biomechanical study of biodegradable posterior Poly-dl-lactic acid lumbar intervertebral cage

作　　者：李开南[1] 刘建峰[2] 汪学军[1] 兰海 何智勇[1] 熊成东[3] 张明梅 

机构地区：[1]成都铁路中心医院骨科,610081 [2]遵义医学院2002级骨科,研究生563003 [3]中国科学院成都有机化学研究所,610064

出　　处：《中国脊柱脊髓杂志》2007年第1期38-41,共4页Chinese Journal of Spine and Spinal Cord

摘　　要：目的:探讨矩形和圆形两种可生物降解材料制成的腰椎间融合器的生物力学特性。方法:应用可生物降解聚-DL-乳酸材料制成两种腰椎间融合器,矩形融合器前高后低,四壁上下方均呈齿状,内外侧壁上有数个小孔;圆形融合器,圆柱状中空,壁外面有深螺纹,螺纹的凹槽内开有数个小孔。依次在以下六种L4～L5节段新鲜牛标本模型上进行生物力学测试:(1)正常组(完整节段标本模型);(2)单纯椎间盘摘除模型组;(3)椎间髂骨块植入组(植骨块为牛髂骨块制成矩形骨块);(4)椎间置入钛矩形融合器组;(5)椎间置入圆形融合器组(圆形组);(6)椎间置入矩形融合器组(矩形组)。每组均进行前屈、后伸、左右侧弯及左右旋转情况下椎体位移测定。对圆形和矩形融合器在离体装载骨和未装载骨的状态下进行压缩载荷实验。结果:生物力学测试结果表明,与正常组活动范围比较,圆形组背伸时和矩形组左侧弯时活动度有显著性差异(P<0.05);与髂骨植骨组比较,圆形组在背伸时有显著统计学差别(P<0.05),矩形组各方向没有统计学差别(P>0.05);圆形组与矩形组之间比较,圆形组背伸时不稳定;与其他各组间比较,钛cage组各方向运动范围均减小,有明显统计学差异(P<0.05)。矩形和圆形融合器未装载骨组最大压缩载荷分别为8000±215N、900±118N,装载骨组最大压缩载荷分别为8300±223N,1000±95N。结论:聚-DL-乳酸生物降解材料制成的腰椎间融合器能够满足腰椎生物力学稳定性要求,且矩形融合器在性能上优于圆形融合器。Objective：To evaluate biomechanical characteristic of cylindrical and rectangular bioresorbable cages of poly-dl-lactic acid （PDLLA）.Method：The rectangular cages made of PDLLA were hollow with the feature of higher in anterior edge and lower in posterior edge.The circumferential walls were tooth-like,with a few small holes in its medial wall.The round-shape cages were designed to be cylindrical and hollow with screw.There were several small holes in the concave of the whorl.The biomechanical tests were carried out under the following 6 conditions： （ 1 ） normal group （intact spinal column） ; （2） removal of intervertebral disc ; （3） implantation of iliac crest bone; （4）implantation of titanium cage; （5）implantation of cylindrical PDLLA cage; （6）implantation of rectangular PDLLA cage.The cyclic load was applied to the spine under the conditions of flexion/extension,bending laterally and axial rotation.Result：In biomechanical test,compared with normal group,there was significant difference in dorsal extension in cylindrical group and in left collateral flexion in rectangular group.As for biomechanical tests,there was a statistically significant difference with respect to extension in cylindrical group and left bending compared with normal group.Compared with group 3,there was significant difference with respect to extension in group 5,yet no statistical difference in group 6 in every dimension.The cylindrical cage showed more unstablility than the rectangular cage in dorsal extension.The range of motion in group 4 was lower than that in any other group in every direction,which had significant difference.On the cylindrical group and the rectangular group,the maximum compressing load with respect to the cage implantation alone was 8000±215N and 900±118N respectively,yet 8300±223N and 1000±95N for cage implantation combined with bone graft.Conclusion：The PDLLA lumbar intervertebral cage could meet the demands of lumbar biomechanical stability,and the this kind of cage with r

关 键 词：聚-DL-乳酸 生物降解 腰椎 椎间融合器 生物力学 

分 类 号：R318.0[医药卫生—生物医学工程] R318.08[医药卫生—基础医学]