颈腰综合征患者一期行颈椎减压术后腰椎症状改善的影像学预测因素分析

Study on imaging predictive factors of lumbar symptoms improvement in patients with tandem spinal stenosis after primary cervical decompression surgery

中文关键词:  颈腰综合征  颈椎手术  影像学参数  预测因素

英文关键词:Tandem spinal stenosis  Cervical spine surgery  Imaging parameters  Predictive factors

中文摘要:

  【摘要】 目的：观察以脊髓型颈椎病为主要临床表现的颈腰综合征（tandem spinal stenosis，TSS）患者先行颈椎减压手术后腰椎症状改善情况与影像学参数的关系，探讨相关的影像学预测因素。方法：回顾性分析2015年1月~2022年12月在我院一期行颈椎减压手术的69例TSS患者的临床资料，年龄41~86岁（64.3±10.5岁），随访24~48个月（33.8±5.5个月）。记录并统计所有患者术前的症状、体征、Nurick步态分级和术前及末次随访时的颈椎日本骨科协会（Japanese Orthopaedic Association，JOA）评分、腰椎JOA评分；根据末次随访时腰椎JOA评分相对于术前的改善情况将患者分为改善组（n=37）和未改善组（n=32），在影像学资料上测量两组患者的脊髓压缩比和颈髓最狭窄处硬膜囊横截面积、C3~C7椎管与椎体的比值和椎管实际宽度、L1~L5的椎管实际宽度，按Lee等提出的颈椎和腰椎椎管狭窄评分标准评估椎管狭窄情况，统计颈椎椎管狭窄评分≥1的颈椎个数、颈椎椎管最狭窄处评分和颈椎椎管狭窄总评分，腰椎椎管狭窄评分≥1的腰椎椎管狭窄个数、腰椎椎管最狭窄处评分和腰椎椎管狭窄总评分，采用t检验、χ2检验或曼-惠特尼U检验比较两组间的差异。对两组有统计学差异的计量资料采用受试者工作特征曲线（receiver operating characteristic，ROC）确定参数的最佳阈值，计算ROC曲线下面积（area under the ROC curve，AUC）及其相应的95%置信区间（confidence interval，CI），采用多因素Logistic回归分析确定TSS患者一期行颈椎减压手术后腰椎症状未改善的影像学预测因素。结果：未改善组腰椎椎管狭窄总评分显著性高于改善组（5.00±1.68 vs 2.68±1.23，P＜0.001），椎管狭窄评分≥1的腰椎个数显著性多于改善组（2.47±0.84个 vs 1.86±0.95个，P=0.004），马尾神经冗余征阳性患者比例显著性高于改善组（14/18 vs 6/13，P=0.017）。腰椎椎管狭窄总评分的AUC为0.864（P＜0.001，95%CI 0.779~0.950），诊断效能最佳阈值为3.5（灵敏度81.3%，特异性75.7%）；椎管狭窄评分≥1的腰椎个数AUC为0.691（P=0.007，95%CI 0.565~0.817），诊断效能最佳阈值为1.5（灵敏度87.5%，特异性56.8%）。多因素Logistic回归分析显示腰椎椎管狭窄个数＞1.5与腰椎症状改善无显著相关性（OR=1.493，95%CI 0.392~5.686，P=0.557）；马尾神经冗余征阳性与腰椎症状改善无显著相关性（OR=2.815，95%CI 0.740~10.711，P=0.129）；腰椎椎管狭窄总评分>3.5与腰椎症状改善有显著相关性（OR=10.983，95%CI 3.261~36.994，P＜0.001），为TSS患者一期颈椎减压手术后腰椎症状不改善的独立危险因素。结论：腰椎椎管狭窄总评分＞3.5的TSS患者一期颈椎减压手术后腰椎症状改善的可能小。

英文摘要:

  【Abstract】 Objectives: To investigate the relationship between the improvement of lumbar symptoms and imaging parameters in patients with tandem spinal stenosis(TSS) primarily manifesting as cervical spondylotic myelopathy(CSM) after initial cervical decompression surgery, and to explore related imaging predictive factors. Methods: A retrospective analysis was conducted on 69 TSS patients who underwent primary cervical decompression surgery, with an average age of 64.3±10.5 years(ranging from 41 to 86 years old) and a follow-up period of 33.8±5.5 months(ranging from 24 to 48 months). Preoperative symptoms and signs, Nurick gait classification, and preoperative and final follow-up Japanese Orthopaedic Association(JOA) scores for both the cervical and lumbar spine were recorded and analyzed. The patients were divided into an improvement group(n=37) and a non-improvement group(n=32) based on the improvement conditions of lumbar spine JOA scores at the final follow-up. Imaging parameters were measured including spinal cord compression ratio, cross-sectional area of the dural sac at the narrowest point of the cervical spinal cord, the ratio of the vertebral canal to the vertebral body and the actual spinal canal width from C3 to C7, and the actual width of the vertebral canal from L1 to L5. The conditions of spinal canal stenosis were evaluated according to the grading system of spinal canal stenosis of cervical and lumbar spine proposed by Lee et al, and the number of cervical vertebrae with a stenosis score ≥1, score at the narrowest part of cervical spinal canal, and the total score of cervical stenosis, as well as the number of lumbar vertebrae with a stenosis score ≥1, score at the narrowest part of lumbar spinal canal, and the total score of lumbar stenosis were calculated. Intergroup comparisons were performed using t tests, chi-square tests, and Mann-Whitney U tests. For the statistic data with statistical differences between the two groups, receiver operating characteristic(ROC) curve was used to determine optimal thresholds for each parameter, and the area under the ROC curve(AUC) and its corresponding 95% confidence interval(CI) were calculated. Multivariate logistic regression analysis was conducted to identify radiological predictive factors for non-improvement of lumbar symptoms in TSS patients. Results: The non-improvement group was significantly higher than the improvement group in the total score of lumbar stenosis(5.00±1.68 vs 2.68±1.23, P<0.001), the number of lumbar vertebrae with a stenosis score ≥1(2.47±0.84 vs 1.86±0.95, P=0.004), and the prevalence of redundant nerve roots(14/18 vs 6/13, P=0.017). The AUC of the total lumbar stenosis score was 0.864(P<0.001, 95%CI 0.779-0.950), with an optimal threshold of 3.5(sensitivity: 81.3%; specificity: 75.7%). The AUC of the number of lumbar vertebrae with a stenosis score ≥1 was 0.691(P=0.007; 95%CI 0.565-0.817), with an optimal threshold of 1.5(sensitivity: 87.5%; specificity: 56.8%). Multivariate logistic regression showed that the number of lumbar spinal stenosis >1.5(OR=1.493; 95%CI 0.392-5.686; P=0.557) and presence of redundant nerve roots(OR=2.815; 95%CI 0.740-10.711; P=0.129) had no significant relationship with improvement of lumbar symptoms. The total lumbar stenosis score >3.5 was significantly related with improvement of lumbar symptoms(OR=10.983; 95%CI 3.261-36.994; P<0.001), which was an independent risk factor for non-improvement in lumbar symtoms after initial cervical decompression in TSS patients. Conclusions: When the total score of lumbar spinal stenosis exceeds 3.5 in TSS patients, the possibility of improvement in lumbar symptoms after initial cervical decompression is small.