后路椎板切除侧块螺钉固定治疗多节段颈椎病术后脊髓后移和膨胀变化及其与疗效的相关性

The change and relationship between clinical outcome and backward translation and expansion of spinal cord in multilevel cervical myelopathy after laminectomy and lateral mass screw fixation

中文关键词:  颈椎病  椎板切除  脊髓后移  疗效  相关性

英文关键词:Cervical myelopathy  Laminectomy  Spinal cord shift  Outcome  Correlation

中文摘要:

  【摘要】 目的：探讨后路椎板切除减压侧块螺钉固定治疗多节段颈椎病术后脊髓后移和膨胀变化及其与疗效的相关性。方法：回顾性分析2011年7月～2014年1月在我院采用后路椎板切除侧块螺钉固定术治疗并获得随访的32例多节段颈椎病患者。在颈椎中立侧位X线片上测量手术前后C2~C7 Cobb角；利用photoshop cs5软件在MRI矢状位T2加权像上选择正中切面，测量获得减压的各间隙上位椎体后下缘分别与脊髓前缘、脊髓后缘的距离，并计算获得减压各间隙的脊髓膨胀距离及脊髓中点后移距离，脊髓整体后移距离和平均膨胀距离为各节段脊髓中点后移距离和膨胀距离的平均值。记录术前及末次随访JOA评分并计算JOA评分改善率。比较手术前后C2~C7 Cobb角及JOA评分变化，并对脊髓整体后移距离与术后颈椎Cobb角、JOA评分改善率与术后脊髓整体后移距离及平均膨胀距离进行相关性分析。手术前后C2~C7 Cobb角及JOA评分比较采用配对t检验，相关性分析采用Pearson分析。结果：术后随访15.8±4.7个月（11～22.5个月）。术后2例患者出现C5神经根麻痹症状，经对症治疗后3周~3个月逐渐好转。手术前、后C2~C7 Cobb角分别为 5.8°±1.2°和18.5°±5.5°，JOA评分分别为8.8±2.5分和14.5±2.0分，手术前后差异均有统计学意义（P＜0.05）。JOA评分改善率为（65.4±34.4）%（26%~100%）。术后脊髓整体后移距离为2.7±1.8mm（1.0~4.5mm），脊髓平均膨胀距离为1.9±1.4mm（0.8~3.4mm）。术后脊髓整体后移距离与术后C2~C7 Cobb角无明显相关性（r=0.11，P>0.05）；JOA评分改善率与术后脊髓整体后移距离呈低度相关（r=0.40，P=0.025），与脊髓平均膨胀距离中度相关（r=0.67，P=0.037）。结论：后路椎板切除钉棒固定治疗多节段脊髓型颈椎病，通过脊髓后移及膨胀的变化取得较满意的疗效，但不能依赖重建的颈椎前凸获得脊髓的后移。JOA评分改善率与术后脊髓整体后移距离及平均膨胀距离呈正相关性。

英文摘要:

  【Abstract】 Objectives: To investigate the change of spinal cord backward drift and expansion after posterior laminectomy decompression and lateral mass screw fixation for multilevel cervical myelopathy and the relationship between curative effect and the spinal cord′s change. Methods: From July 2011 to January 2014, 32 patients with multilevel cervical myelopathy underwent laminectomy and lateral mass screw fixation in our hospital. C2-7 Cobb angle was measured in neutral neck lateral radiograph before and after operation. Using Photoshop cs5 software, the distance of each intervertebral space after decompression from the upper posterior vertebral body margin to the anterior and posterior margin of the spinal cord was measured respectively in the MRI sagittal T2 weighted median film. And the distance of each intervertebral space of the expansion and the midpoint of backward drift of spinal cord was calculated and the average value was take. The JOA scores at preoperation and the last follow-up were recorded, as well as the improvement rate. The changes of C2-C7 Cobb angle and JOA score were compared before and after operation. Correlation analysis was performed between the whole spinal cord drifting distance and postoperative cervical Cobb angle, and between the improvement rate of JOA and the whole drifting distance/expansion of spinal cord. The preoperative and postoperative C2-C7 Cobb angle and JOA score were compared by paired t test, and Pearson analysis was used for the analysis of correlation. Results: Patients were followed up for 11 to 22.5 months, averaging 15.8±4.7 months. The symptoms improved after surgery, preoperative and postoperative Cobb angle was 5.8°±1.2° and 18.5°±5.5° respectively, JOA score was 8.8±2.5 and 14.5±2.0 respectively, and the difference was statistically significant(P<0.05). The JOA improvement rate was (65.4±34.4)%（26%-100%）. The whole spinal cord drifting distance was 2.7±1.8mm(1.0-4.5mm), and the average spinal cord expansionary distance was 1.9±1.4mm(0.8-3.4mm). No obvious correlation was found between spinal cord drifting distance and postoperative cervical curvature(r=0.11, P>0.05). Low correlation between the JOA recovery rate and the whole spinal cord drifting distance(r=0.40, P=0.025) and moderate correlation between the JOA recovery rate and the average spinal cord expansionary distance(r=0.67, P=0.037) were noted. 2 cases suffered from C5 nerve root palsy and were cured by correspondant treatment for 3 weeks to 3 months. Conclusions: Laminectomy and lateral mass screw fixation is satisfactory due to its back drifting and expansion of spinal cord. There is positive correlation of the JOA recovery rate with the spinal cord drifting and expansion distance.