保留脊柱后方韧带复合体腰椎管扩大术的基础研究与临床应用

BASIC AND CLINICAL STUDIES ON LUMBAR VERTEBRAL CANAL EXPANSION WITH PRESERVATION OF POSTERIOR LIGAMENTS COMPLEX

目的评价保留脊柱后方韧带复合体腰椎管扩大术临床疗效及生物力学特征。方法取8个新鲜腰骶椎标本,根据处理方法,分为3组。A组:8个完整腰骶椎标本进行生物力学测定;B组:A组测试后,切除L3～53个全椎板,保留后方韧带复合体,即为保留脊柱后方韧带复合体的腰椎管扩大术(改良术式);C组:B组测试后,将保留的韧带复合体切除,即为传统术式。3组均行轴向压缩实验、三点弯曲实验及扭转实验。2000年6月-2006年6月,收治309例腰椎管狭窄症患者,行保留脊柱后方韧带复合体腰椎管扩大术。其中男152例,女157例;年龄20～80岁,平均57.2岁。病程3个月～41年。单纯腰椎管狭窄症55例;腰椎管狭窄合并腰椎间盘突出症254例,其中合并L4、5椎间盘突出105例,L4～S1椎间盘突出56例,L5、S1椎间盘突出86例,L2、3高位腰椎间盘突出7例。术后采用JOA下腰痛手术疗效评分标准、患者手术满意度及影像学观察进行疗效评定。结果轴向压缩实验:前屈时,A、B组应变、应力、轴向位移均小于C组(P<0.01);轴向刚度大于C组(P<0.01)。后伸时,A、B、C3组间上述指标差异无统计学意义(P>0.05)。三点弯曲实验:在相同弯矩下,挠度、倾角、弯曲刚度A、C组及B、C组比较,差异均有统计学意义(P<0.01),A、B组间差异无统计学意义(P>0.05)。扭转实验:相同扭角条件,B组承载的扭矩大于C组(P<0.01);相同扭矩条件,B组扭角小于C组(P<0.01),B组扭转刚度大于C组(P<0.01)。临床应用结果:术中神经根牵拉伤7例;术后脑脊液漏5例,伤口感染4例,经处理后痊愈。309例均获随访,随访时间1～7年。根据JOA下腰痛评分标准,JOA评分平均改善率为86.0%;其中优163例,良112例,可34例,优良率89%。X线片未见椎体不稳。患者手术满意度为87%。结论保留脊柱后方韧带复合体腰椎管扩大术有利于保持脊柱的力学稳定性,疗效佳。

Objective To investigate the clinical application and efficacy of lumbar vertebral canal expansion with preservation of posterior ligaments complex, and to study its biomechanical properties. Methods Eight fresh lumbosacral cadaveric samples were divided into 3 groups. In group A, 8 intact lumbosacral cadaveric samples were used for biomechanical test. In group B, L3-5 laminectomy were, after the test in group A, performed and the posterior ligaments complex was preserved. In group C, the posterior liagments complex was excised after the test in group B. In all 3 groups, the axial compression test, three-point bending test and torsional test were conducted. From June 2000 to June 2006, 309 patients （152 males and 157 females, aged 20-80 years with the average of 57.2 ） with lumbar canal stenosis received operation of the lumbar vertebral canal expansion with preservation of posterior ligaments complex. The course of disease was 3 months to 41 years. There were 55 patients suffering from pure lumbar canal stenosis, and 254 from lumbar canal stenosis combined with lumbar disc herniation, among which 105 were at L4,5 level, 56 at L4-S1 level, 86 at L5, S1 level, and 7 at L2.3 level. The therapeutic effect was assessed based on the JOA low back pain scoring system, the satisfaction degree of patient and radiographical observation. Results The axial compression test was performed. In the position of forward bending, stress, strain and axial displacement were smaller in groups A, B than those in group C, and axial stiffness in groups A, B was higher than those in group C, and the difference was significant （P 〈 0.01）. In the position of backward extension, there was no significant difference among 3 groups （P 〉 0.05）. Concerning the three-point bending test, under the same bending moment, there was a significant difference in deflection, dip and bending rigidity between group A and group C, and also between group B and group C （P 〈 0.01）, but no significant difference betweengroup A and group B （P 〉 0.05）. In the torsional test, under the same torsional angle, the torque in group B was bigger than that in group C （P 〈 0.01）. Under the same torque, the torsional angle in group B was smaller than that in group C （P 〈 0.01）, and the torsional stiffness in group B was higher than that in group C （P 〈 0.01）. The complications included 7 cases of distraction of nerve root, 5 leakage of cerebrospinal fluid and 4 wound infection. MI complications were treated and restored completely. M1 patients were followed up for 1-7 years. According to the JOA low back pain scoring system, the improvement rate averaged 86.0%. Of all the 309 cases, 163 were excellent, 112 good, 34 fair, and the choiceness rate was 89%. The satisfaction rate of patient was 87%. There was no radiographic vertebral instability postoperatively. Conclusion The lumbar vertebral canal expansion with preservation of posterior ligaments complex is conducive to maintaining the stability of lumbar spine and have good clinical outcomes.