利用成年猪脊柱制作胸腰段后凸畸形模型进行脊柱三维运动实验

目的]探讨应用成年猪脊柱制作胸腰段后凸畸形模型进行生物力学实验研究的可行性,以及胸腰段后凸畸形对腰椎三维运动的生物力学影响.方法]收集24例成年家猪胸腰椎脊柱新鲜标本,随机分为三组,制造两个Cobb角度水平的胸腰段后凸畸形和相应的腰椎过度前凸模型,进行脊柱三维运动实验,测量L2、3和L4、5的前屈/后伸、左/右侧弯、左/右旋转的运动范围( ROM)以及所对应的中性区(NZ)的大小,对各组数值进行方差分析,用snk(q检验)法对分组变量进行多重比较.结果]后凸的胸腰段对邻近运动节段(L2、3)矢状面上的运动(前屈/后伸)ROM以及NZ的影响更明显,P＜0.05,而左/右侧弯、左/右旋转的ROM及NZ没有统计学差异,P＞0.05；而下腰椎运动节段(L4、5)的前屈/后伸、左/右侧弯、左/右旋转的ROM及NZ均没有统计学差异,P＞0.05.结论]利用成年猪脊柱制作胸腰段后凸畸形模型进行脊柱三维运动实验是可行、简便、有效的；腰椎前屈/后伸运动范围的过度增大,是胸腰段后凸畸形后为维持脊柱矢状面平衡的一个重要代偿改变,且ROM的增大以上腰椎的改变更为明显.

Model of thoracolumbar kyphosis with fresh adult porcine spine specimens:a biomechanics study

Objective]To investigate the feasibility of animal modle of the kyphosis of thoracolumbar spine with fresh adult porcine spine specimens and changes of the range of 3D-motion of lumbar vertebrae secondary to the kyphosis of thoracolumbar spine.Methods]Twenty-four fresh porcine thoracolumbar spine(T10~L6) specimens were divided into 3 groups at random(8 in each group): the normal or intact group(group Ⅰ),experiment group 1(group Ⅱ Cobb angle =36.57°±5.71°),and experiment group 2(group Ⅲ Cobb angle =67.98°±1.59°).Pure moments of flexion-extension,left-right axial torsion,and left-right lateral bending were measured with a flexibility machine,and the ROM(range of motion) and NZ(neutral zone) of the L2、3 and L4、5 vertebrae were recorded with a motion measurement system after preconditioning.The measued results of ROM & NZ were statistically analyzed by means of one-way ANOVA and snk-test.Results]The average of ROM and NZ of L2、3’ s flexion-extension in kyphosis groups(group II and group III) were larger than that in the normal group(P<0.05),and the kyphosis Cobb’s angle,the ROM and NZ of L2、3’ s flexion-extension were also larger.However it was found that the average of ROM and NZ of L2、3’ s left-right axial torsion and left-right lateral bending in kyphosis groups(group II and group III) had no significant difference compared with the normal group(P>0.05).Statistical difference was not found in both ROM and NZ of L4、5’ s moments of flexion-extension,left-right axial torsion,and left-right lateral bending among the three groups(P>0.05).Conclusion]It is a feasible,convenient and effective meathod for creating a animal modle of the kyphosis of thoracolumbar spine with fresh adult porcine spine specimens.Over augmentation of the ROM and NZ of upper lumbar flexion-extension are main compensations secondary to the kyphosis of the thoracolumbar spine.However,ROM and NZ of upper lumbar left-right axial torsion and left-right lateral bending have no changes.