腰椎微创极外侧经椎间孔椎体间融合术的生物力学评价

目的 通过生物力学测试比较腰椎微创极外侧经椎间孔椎体间融合术(E-TLIF)与传统术式的生物力学稳定性.方法 采用正常猪脊柱运动节段标本24副,随机进行不同处理后分为正常对照组(CG组)、单纯椎弓根螺钉内固定组(SG组)、经椎间孔腰椎体间融合术(TLIF)组、E-TLIF组；分别测试不同载荷时各组在轴向压缩、前屈、后伸、左侧屈时的应变、位移变化及左侧扭转稳定性等生物力学指标,并进行统计学比较.结果 E-TLIF组的载荷-应变和位移、最大载荷下轴向稳定性、扭转稳定性等生物力学指标与TLIF组比较差异无统计学意义(P＞0.05).在左侧屈活动中,E-TLIF组[线性位移(3.40 ±0.09)mm,角位移2.57°±0.12°]稳定性优于TLIF组[线性位移(3.98 ±0.22)mm,角位移3.03°±0.18°](t=2.61,P＜0.05),E-TLIF组和TLIF组在轴向(前屈、后伸)、侧屈、旋转方向上的力学稳定性均高于SG组(t=4.17 ～4.53,P＜0.01).结论 E-TLIF手术是一种安全、有效的腰椎椎体间融合术式.

Bio-mechanical evaluation of extreme lateral transforaminal lumbar interbody fusion

Objective To evaluate the feasibility and post-operation stability of extreme lateral transforaminal lumbar interbody fusion (E-TLIF) and other traditional surgical approach via bio-mechanical test.Methods There were 24 normal lumbar spine segment of swine were divided into the following four groups: control group,standard group (internal fixed with pedicle screws only),transforaminal lumbar interbody fusion (TLIF) group and E-TLIF group.The specimen in anteflect,hypsokinesis,lateral flexion and rotate movements were tested respectively with bio-mechanical devices to study on the load-straining changes and biomechanics index.Results After TLIF or E-TLIF,specimen turned out more steady than normal control group(t =4.17-4.53,P ＜0.01 ).Compared with TLIF group [linear displacement (3.98 ±0.22)mm,angular displacement 3.03° ± 0.18°],specimen after E-TLIF [linear displacement (3.40 ±0.09) mm,angular displacement 2.57° ± 0.12°]were more stable in biomechanics index on lateral flection movement ( t =2.61,P ＜ 0.05 ),but no difference on axial or rotational movements ( P ＞ 0.05 ).Conclusion E-TLIF is a safe and more efficient operation approach.