PLIF 和 TLIF 两种腰椎间融合术的生物力学测试

目的：比较两种椎间融合方式，即后路椎间融合术（ PLIF ）、椎间孔入路椎间融合术（ TLIF）术后的生物力学差异。方法：选取15具新鲜家猪腰椎标本，随机分为3组，每组5个标本，模拟临床手术方式行PLIF、TLIF，在微机控制电子万能实验机上测试其生物力学特性。结果：与正常对照组相比，PLIF组和TLIF组的前屈后伸方向的抗弯强度明显增强，有统计学差异，P＜0．05；实验组间无统计学差异。两试验组与对照组之间轴向应力没有统计学差异，而相应的抗扭转强度则有所减弱，有统计学差异，P＜0．05。实验组间，TLIF组的抗扭转强度强于PLIF组，有统计学差异，P＜0．05。结论：经PLIF、TLIF术后，腰椎的稳定性均有所下降。在屈伸、旋转运动状况下，PLIF组和TLIF组稳定性减弱，但在左右侧弯、轴向刚度的变化上，与正常对照组差别不大。 TLIF组抗扭转强度强于PLIF组。

Biomechanical Testing between the Two Lumbar Fusion Surgery of PLIF and TLIF

Objective： To compare the biomechanical differences of two interbody fusion methods in postoperative, namely, posterior lumbar interbody fusion （ PLIF） and transforaminal interbody fusion （ TLIF） .Method： 15 fresh pig lumbar spine specimens were randomly divided into three groups （ control group,PLIF group and TLIF group）.There were five specimens in every group .PLIF group and TLIF group were used to simuLate clinical surgical to test their biomechanical properties with the electronic testing ma -chine controlled by computer .Result： Compared with control group , the mean flexion stiffness of TLIF group and PLIF group was significantly increased , P〈0.05; there was no significant difference between the experimental groups .The axial stress between the two experimental groups and control group was no statisti-cally significant.But the corresponding torsional strength weakened significantly , P〈0.05.In the experimen-tal groups, the torsional strength of TLIF group was stronger than the PLIF group , P〈0.05.Conclusion：The stability of the lumbar spine has declined after the surgery of PLIF and TLIF .Inflexion, rotation situation , the stability of PLIF group and TLIF group weakened;but in lateral bending and axial stiffness , little differ-ence with the control group .The torsional strength of TLIF group is stronger than the PLIF group .