腰椎微创极外侧经椎间孔椎体间融合术的生物力学评价

Bio-mechanical evaluation of extreme lateral transforaminal lumbar interbody fusion

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问融合术（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TuF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。

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-meehanical 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 biomeehanies 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.