站立前屈位X线片联合仰卧位MRI评估退变性腰椎滑脱节段的稳定性

Application of standing flexion X-ray and supine MRI to evaluate degenerative lumbar spondylolisthesis segmental instability

中文关键词:  退变性腰椎滑脱  腰椎失稳  过伸过屈位X线片  仰卧位MRI

英文关键词:Degenerative lumbar spondylolisthesis  Lumbar instability  Flexion -extension X-ray  Supine position MRI

中文摘要:

  【摘要】 目的：探讨站立前屈位X线片联合仰卧位MRI评估退变性腰椎滑脱节段稳定性的可靠性及可行性。方法：回顾性分析2016年1月1日~2018年6月30日在山东大学齐鲁医院（青岛）脊柱外科住院治疗的87例退变性腰椎滑脱症患者的临床资料。男20例，女67例；年龄47~87岁（65.9±9.0岁）。滑脱节段：L3 10例，L4 66例，L5 11例；依据Meyerding分类，Ⅰ度滑脱82例，Ⅱ度滑脱5例。所有患者均在站立位获得前屈、后伸侧位X线片及仰卧位MRI片，利用图像存档通信系统（PACS系统）对影像数据进行回顾性分析，包括站立位前屈（F）、后伸（E）X线片和仰卧位MRI（S），MRI图像选取T1加权正中矢状面图像。将滑脱距离与椎体宽度的百分比定义为滑脱百分比并用于最后分析。计算出F与E、F与S之间滑脱百分比的差值定义为滑移率。滑移率≥8%定义为节段不稳定。结果：三种体位平均滑脱百分比F位最大[（16.97±5.93）%]，其后依次为E位[（14.04±6.38）%]和S位[（9.89±5.34）%]，三种体位之间有统计学差异（F-E：P＜0.01；F-S：P=0.00；E-S：P=0.00）。F-S、F-E之间平均滑移率分别为（7.08±4.60）%（-0.49%~24.32%）、（2.93±3.29）%（-3.46%~11.24%），两者之间有统计学差异（P=0.00）。以滑移率≥8%为标准，诊断为节段不稳的患者共40例，其中F-S发现37例（92.5%），F-E发现7例（17.5%）；F-E显示滑脱节段不稳的7例中，4例F-S也显示不稳，另3例（7.5%）F-S未显示不稳。结论：对于退变性腰椎滑脱节段稳定性的评估，应用站立前屈侧位X线片结合平卧位MRI比站立前屈后伸位X线片能更好地显示滑脱节段的不稳定；站立前屈位X线片联合仰卧位MRI片可明显提高诊断的准确性，降低漏诊率。

英文摘要:

  【Abstract】 Objectives: To investigate the reliability and feasibility in evaluating degenerative lumbar vertebral instability through combined standing flexion X-ray with supine MRI. Methods: Retrospectively reviewed the 87 patients with degenerative lumbar spondylolisthesis treated in the spinal surgery department of Qilu Hospital of Shandong University(Qingdao) from January 2016 to June 2018. Among them, 67 cases were female and 20 cases were male, with an average age of 65.9±9.0 years(ranged from 47-87). Spondylolisthesis segment distribution: 10 cases at L3 segements, 66 cases at L4, and 11 cases at L5 segement. According to Meyerding classification, 82 cases were of degree Ⅰ, and 5 cases were of degree Ⅱ has. All the patients underwent flexion-extension X-ray in standing position and MRI in supine position. Image data were retrospectively analyzed through Picture Archiving and Communication System(PACS), including data of standing flexion position X-ray(F), extension position X-ray(E) and supine MRI(S). For the MRI image, T1 weighted and mid-sagittal were selected. The percentage of slip distance to the width of vertebral body was defined as slip percentage for analysis. The difference of slip percentage between F and E position, F and S position was defined as slip rate. Slip rate≥8% was defined as segmental instability. Results: The average slip percentage was the highest at F position(16.97±5.93)%, followed by E position(14.04±6.38)% and S position(9.89±5.34)%. There were significant statistical differences between the three positions (F-E: P<0.01; F-S, P=0.00; E-S: P=0.00). The average slip rate of F-S and F-E was (7.08±4.60)%(-0.49%-24.32%) and (2.93±3.29)%(-3.46%-11.24%) respectively, with significant statistical differences(P=0.00). Defining slip rate≥8% as the standard, 40 cases were diagnosed as segmental instability. Among them, F-S has 37 cases(92.5%), F-E has 7 cases(17.5%). Of the 7 cases shown segmental instability in F-E, 4 cases also showed instability in F-S, while the other 3 cases(7.5%) didn′t show instability in F-S. Conclusions: For the evaluation of segmental stability of degenerative lumbar spondylolisthesis, the application of standing flexion lateral X-ray combined with MRI in the supine position can better show segmental instability of the sliding segment than the X-ray of standing flexion-extension. The combination of standing flexion position X-ray and supine position MRI significantly improved the diagnostic sensitivity and reduced the rate of missed diagnosis.