脊髓线分型在颈椎后路单开门椎管成形术中的应用

Application of classification of spinal cord line in posterior cervical open-door laminoplasty

中文关键词:  脊髓线  分型  减压  颈椎  椎管成形术

英文关键词:Spinal cord line  Classification  Decompression  Cervical vertebra  Laminoplasty

中文摘要:

  【摘要】 目的：介绍脊髓（spinal cord，SC）线的定义、临床分型及其在颈椎后路单开门椎管成形术中的应用策略，并对其可信度和可重复性进行检验分析。方法：回顾性分析2018年1月~2020年12月于温州医科大学附属第二医院接受颈椎后路单开门椎管成形术进行脊髓减压的86例患者的临床资料，其中男51例，女35例，年龄34~77岁，术后随访时间12~36个月。根据术前MRI上SC线与前方致压物的关系，将其分为3种类型：Ⅰ型为致压物在SC线前方，Ⅱ型为致压物与SC线接触，Ⅲ型为致压物超过SC线。由5位脊柱外科医师对患者的MRI图像进行独立评估与分型，通过Kappa一致性检验分析其可信度及可重复性。2021年1月~2022年12月招募50例多节段颈髓压迫疾病（脊髓型颈椎病、颈椎后纵韧带骨化、发育性颈椎管狭窄）患者进行前瞻性研究，根据尽量改善SC线分型的原则决定开门节段，随访12~34个月，对回顾性及前瞻性研究的患者均记录术前和末次随访改良脊髓前方压迫程度评分、颈部疼痛视觉模拟评分（visual analogue scale，VAS）、日本骨科协会（Japanese Orthopaedic association，JOA）评分及改善率，采用配对样本t检验比较各型手术前后评分差异，采用单因素方差分析比较三型间评分差异，评估不同SC线分型患者术后脊髓减压情况及临床疗效。结果：回顾性分析的86例患者中SC线Ⅰ型38例，Ⅱ型31例，Ⅲ型17例。观察者间一致性的Kappa系数0.817~0.945；观察者内一致性的Kappa系数为0.891~0.963，可信度及可重复性满意。患者术前各型之间脊髓压迫程度评分、VAS评分无统计学差异（P＞0.05），且末次随访与术前相比均有统计学差异（P<0.05）；Ⅰ型患者末次随访脊髓压迫程度评分和VAS评分最低，Ⅲ型患者最高（P<0.05）；Ⅰ型JOA评分改善率为（73.49±11.26）%，Ⅱ型为（67.08±9.01）%，Ⅲ型为（53.74±7.93）%，三组间有统计学差异（P<0.05）。前瞻性分析的50例患者中SC线Ⅰ型27例，Ⅱ型15例，Ⅲ型8例。术前脊髓压迫程度评分Ⅰ型为3.67±0.47分，Ⅱ型为3.84±0.37分，Ⅲ型为4.00±0.00分，末次随访时Ⅰ型为1.24±0.62分，Ⅱ型为2.60±0.58分，Ⅲ型为3.40±0.52分；Ⅰ型VAS评分由术前6.48±0.85分改善为末次随访时的1.11±0.51分，Ⅱ型由术前6.67±0.90分改善为末次随访时的1.73±0.59分，Ⅲ型由术前7.13±0.64分改善为末次随访时的2.38±0.52分（P<0.05）。Ⅰ型患者末次随访脊髓压迫程度评分和VAS评分最低，Ⅲ型患者最高（P<0.05）。Ⅰ型JOA评分由术前12.07±1.17分改善为末次随访时的15.59±0.69分，Ⅱ型由术前10.93±0.80分改善为末次随访时的14.67±0.72分，Ⅲ型由术前10.13±1.13分改善为末次随访时的13.63±0.74分（P<0.05）。Ⅰ型JOA评分改善率为（72.50±12.38）%，Ⅱ型为（61.99±9.78）%，Ⅲ型为（51.25±5.19）%，三组间有统计学差异（P<0.05）。结论：SC线分型实用可靠，其可信度和可重复性较好。选择适宜开门节段使SC线分型为Ⅰ型的后路单开门椎管成形术可解除前方脊髓压迫；当SC线分型为Ⅲ型时，后路手术后前方仍有压迫，需考虑行前路手术。

英文摘要:

  【Abstract】 Objectives: To introduce the definition of the spinal cord(SC) line, and its clinical classification and application strategies in posterior cervical open-door laminoplasty, and to examine and analyze the credibility and repeatability of this classification. Methods: The clinical data of a total of 86 patients who underwent cervical open-door laminoplasty via posterior approach in The Second Affiliated Hospital of Wenzhou Medical University from January 2018 to December 2020 were analyzed retrospectively. There were 51 males and 35 females, aged 34-77 years old, with postoperative follow-up period ranging from 12 to 36 months. The patients were classified into three types based on the location relationships between the SC line and compressor in the preoperative MRI: Type Ⅰ, the compressor at compression level did not exceed the SC line; Type Ⅱ, the compressor contacted the SC line; Type Ⅲ, the compressor exceeded the SC line. Five spinal surgeons independently evaluated and classified the MRI images of the patients, and Kappa consistency tests were performed to analyze the credibility and repeatability. 50 patients with multilevelcervical spinal cord compression diseases(cervical spondylotic myelopathy, ossification of the posterior longitudinal ligament, and developmental cervical spinal canal stenosis) were recruited and treated for a prospective study from January 2021 to December 2022, and the range of open-door segments was determined under the principle of improving the SC line classification as much as possible. The patients were followed up for 12 to 34 months. The modified anterior spinal cord compression score, neck pain visual analogue scale(VAS), Japanese Orthopaedic Association(JOA) score and recovery rates of the patients were recorded pre-operatively and at final follow-up in both retrospective and prospective studies. Paired samples t test was used to compare the scores before and after surgery in each type of patients, and one-way ANOVA was used to compare the scores between the three groups, to assess the postoperative spinal cord decompression and clinical outcomes of the different SC line types. Results: Among the 86 patients analyzed retrospectively, 38 were Type Ⅰ, 31 were Type Ⅱ and 17 were Type Ⅲ. The Kappa coefficient was 0.817-0.945 for inter-observer consistency, which was 0.891-0.963 for intra-observer consistency, indicating satisfactory credibility and repeatability. There was no significant difference in modified anterior spinal cord compression score and VAS score between the three types of patients before surgery(P>0.05), and all of them were statistically different at the final follow-up compared with the preoperative period(P<0.05). The modified anterior spinal cord compression score and VAS score were the lowest at the final follow-up in Type Ⅰ, which were the highest in Type Ⅲ(P<0.05). The JOA recovery rate was (73.49±11.26)% in Type Ⅰ, (67.08±9.01)% in Type Ⅱ, and (53.74±7.93)% in Type Ⅲ, with statistically significant differences between the three types(P<0.05). Among the 50 patients analyzed prospectively, 27 were Type Ⅰ, 15 were Type Ⅱ and 8 were Type Ⅲ. The preoperative spinal cord compression score was 3.67±0.47 in Type Ⅰ, 3.84±0.37 in Type Ⅱ, and 4.00±0.00 in Type Ⅲ, which was 1.24±0.62 in Type Ⅰ, 2.60±0.58 in Type Ⅱ, and 3.40±0.52 in Type Ⅲ at the final follow-up, respectively. The VAS score decreased from 6.48±0.85 preoperatively to 1.11±0.51 at final follow-up in Type Ⅰ. Type Ⅱ cases exhibited a decrease in VAS score from 6.67±0.90 preoperatively to 1.73±0.59 at final follow-up. And the VAS score decreased from a preoperative value of 7.13±0.64 to 2.38±0.52 at final follow-up in Type Ⅲ(P<0.05). The modified anterior spinal cord compression score and VAS score were the lowest in Type Ⅰ and the highest in Type Ⅲ at final follow-up(P<0.05). The JOA score improved from 12.07±1.17 preoperatively to 15.59±0.69 at final follow-up in Type Ⅰ. Type Ⅱ cases exhibited an improvement in JOA score from 10.93±0.80 preoperatively to 14.67±0.72 at final follow-up. And the JOA score improved from a preoperative value of 10.13±1.13 to 13.63±0.74 at final follow-up in Type Ⅲ(P<0.05). The JOA recovery rate was (72.50±12.38)% in Type Ⅰ, (61.99±9.78)% in Type Ⅱ, and (51.25±5.19)% in Type Ⅲ, which was statistically different between the three groups(P<0.05). Conclusions: The SC line and its classification are practical and reliable, demonstrating good credibility and repeatability. Suitable open-door segment in posterior open-door laminoplasty in patients of Type Ⅰ SC line can make anterior spinal cord compression relieved; And anterior surgery needs to be considered when anterior compression remained after posterior surgery in patients of Type Ⅲ SC line.