L4 ~ 5后路腰椎椎间融合术后腰椎前凸指数对临近节段疾病发生的影响

Effect of postoperative lordosis distribution index on adjacent segment disease after L4-5 posterior lumbar interbody fusion

目的探讨L4~5后路腰椎椎间融合术(posterior lumbar interbody fusion,PLIF)治疗退行性腰椎疾病后腰椎前凸分布指数(lordosis distribution index,LDI)与邻近节段疾病(adjacent segment disease,ASD)的关系。方法纳入本科2009-2014年行L4~5 PLIF治疗退行性腰椎疾病的患者266例,测量术前术后下腰椎脊柱参数,包括下腰椎前凸(lower lumbar lordosis,LLL)、腰椎前凸(lumbar lordosis,LL)、骶骨倾斜角和LDI;记录围术期信息、合并症和术中数据。用logistic回归分析确定ASD的危险因素,绘制Kaplan-Meier曲线比较术后各LDI亚组患者的ASD未患病率。结果ASD的发生率为7.5%。logistic回归显示:BMI增加1个单位的ASD发生风险提高1.252倍,术后异常LDI的患者发生ASD的风险是术后正常LDI患者的5.450倍。Kaplan-Meier分析显示:术后低LDI组、高LDI组与中LDI组相比,ASD 10年未患病率有统计学差异(71.43%和78.30 vs 90.95%,P均<0.05)。结论BMI和术后LDI分级是ASD的危险因素。术后LDI异常的患者较术后LDI正常的患者更容易发生ASD。

Objective To investigate the relationship between postoperative lordosis distribution index(LDI)and adjacent segment disease(ASD)after L4-5 posterior lumbar interbody fusion(PLIF)for spinal degenerative disease.Methods Totally 266 subjects who underwent L4-5 PLIF in our center for spinal degenerative disease from 2009 to 2014 were included in our study.The average follow-up time was 85 months.Lower lumbar lordosis(LLL),lumbar lordosis(LL)and LDI on the pre-and postoperative radiograph were measured.Perioperative information,comorbidities and operative data were documented.Logistic regression analysis was used to identify the risk factors of ASD.Kaplan-Meier curve was plotted for the comparisons of ASD-free survival of 3 different postoperative LDI subgroups.Results The incidence of ASD was 7.5%.For every 1-unit increase in BMI,adjacent segment disease risk increased by 25%.Patients with abnormal postoperative LDI had a 5.45 times higher risk of ASD than patients with normal postoperative LDI.Kaplan-Meier curves showed a marked difference in ASD-free survival in low and high LDI subgroups compared to moderate LDI group(71.43%and 78.30 vs 90.95%,P<0.05,respectively).Conclusion Higher BMI and abnormal postoperative LDI are risk factors of ASD.Patients with abnormal postoperative LDI are more likely to develop ASD than those who had normal postoperative LDI.