Clinical Study of Cervical Spondylotic Myelopathy Treated by Single Door Laminoplasty
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摘要:
目的 通过分析颈椎单开门成形术术后患者远期临床疗效,探讨颈脊髓面积改变量与患者术后远期临床疗效的相关性。 方法 回顾性分析自2015年11月至2021 年6月期间在海南医学院第一附属医院行颈椎单开门成形术的60例脊髓型颈椎病患者。术后末次随访时采用日本骨科协会(JOA)改善率评估患者远期临床疗效。将末次随访JOA改善率 > 60%的32例患者分为预后良好组,而末次随访JOA改善率≤60%的28例患者分为预后不良组。记录2组患者性别、年龄、症状持续时间、失血量、手术时间、术前及术后JOA评分。并通过术前、术后颈椎MRI、CT及X射线测量椎管矢状面直径、颈椎曲率指数、颈椎活动度、椎管面积及颈脊髓面积。 结果 预后良好组术后颈脊髓面积改变量为(55±41) mm2显著大于预后不良组的(35±37) mm2,2组间差异具有统计学意义(P < 0.05)。此外,预后良好组术前、术后椎管面积及门轴位置均明显大于预后不良组(P < 0.05)。但2组间术前、术后椎管尺状面直径及颈椎活动度的差异无统计学意义(P > 0.05)。而多因素回归分析显示,术前(OR = 6.924,P < 0.05)及术后JOA评分(OR = 22.000,P < 0.05)、术前椎管面积(OR = 2.518,P < 0.05)和颈脊髓面积改变量(OR = 5.513,P < 0.05)与患者末次随访JOA改善率有关。 结论 SDCL术后颈脊髓面积改变量、术前颈椎管面积、及术前术后JOA评分与术后末次随访时JOA改善率密切相关。术者可依据SDCL术后颈脊髓面积改变量预判患者的远期疗效。 Abstract:Objective By analyzing the long term clinical effect of patients after single open-door cervical laminoplasty, the correlation between the change of cervical spinal cord area and the long term clinical effect of patients was discussed. Methods A retrospective analysis was performed on 60 patients with cervical spondylotic myelopathy who underwent cervical single open-door laminoplasty in the First Affiliated Hospital of Hainan Medical College from November 2015 to June 2021. The long-term clinical efficacy was evaluated by Japanese Orthopaedic Association (JOA ) improvement rate at the last follow-up. 32 patients with JOA improvement rate of > 60% at the last follow-up were divided into good prognosis group, while 28 patients with JOA improvement rate of ≤60% at the last follow-up were divided into poor prognosis group. Gender, age, duration of symptoms, blood loss, operation time, preoperative and postoperative JOA score were observed. Spinal canal sagittal diameter, cervical curvature index, cervical range of motion, spinal canal area and cervical spinal cord area were measured by preoperative and postoperative cervical MRI, CT and X-ray. Results The change of cervical spinal cord area in the good prognosis group was (55 ± 41 ) mm2, which was significantly larger than that in the poor prognosis group (35 ± 37 ) mm2, and the difference between the two groups was statistically significant (P < 0.05 ). The preoperative and postoperative spinal canal area and the axial position in the good prognosis group were significantly larger than those in the poor prognosis group (P < 0.05 ). But there was no significant difference in the preoperative and postoperative spinal canal ulnar diameter and cervical activity between the two groups (P > 0.05 ). Multivariate regression analysis showed that preoperative (OR = 6.924, P < 0.05) and postoperative JOA score (OR = 22.000, P < 0.05 ), preoperative spinal canal area (OR = 2.518, P < 0.05 ) and cervical spinal cord area change (OR = 5.513, P < 0.05 ) were related to the improvement rate of JOA at the last follow-up. Conclusion The change of cervical spinal cord area after SDCL, preoperative cervical spinal canal area, and preoperative and postoperative JOA score are closely related to the improvement rate of JOA at the last follow-up. Surgeons can predict the long-term efficacy of the patients according to the change of cervical spinal cord area after SDCL. -
颈椎单开门成形术 (single-door cervical laminoplasty,SDCL)可适用于后纵韧带骨化、多节段颈椎间盘突出症及椎管狭窄症等疾病的治疗[1-3]。SDCL通过扩大颈椎椎管容积,增加颈椎受压节段脊髓的活动面积,减轻对颈脊髓神经的受压,从而改善患者的临床症状[4-6]。虽然目前研究表明脊髓型颈椎病患者在SDCL术后可获得令人满意的远期临床疗效,但部分患者在SDCL术后远期治疗效果欠佳[1, 7]。而SDCL术后神经功能的恢复受颈脊髓受压时间、颈椎管容积、术前JOA评分及颈椎硬膜囊的扩张空间等因素的影响[8-13]。日本骨科协会于1975年为定量评估颈椎病患者的脊髓受压程度提出了JOA评分,并通过治疗后JOA评分的改善率来评估患者的疗效[14]。然而依据JOA评分来评估脊髓型颈椎病患者的疗效虽受到学者们的青睐[15-16],但目前很少有研究报道手术治疗后颈脊髓面积的改变量与JOA评分改善率的相关性[17]。因此本研究的目的是分析SDCL术后患者末次随访时JOA改善率,并讨论颈脊髓面积改变量与SDCL术后患者远期预后的相关性。
1. 资料与方法
1.1 一般资料
本研究经过伦理委员会的批准后,纳入自2015年11月至2021 年6月期间在海南医学院第一附属医院接受SDCL治疗的60例患者。其中预后良好组32例患者,其中男18例,女14例,平均年龄(63.5±10.2)岁,手术出血量(238±155)mL、手术时间(136±38)min及住院时间(9.8±2.6)d、随访时间(18.8±13.1)月;预后不良组28例患者,其中男15例,女13例,平均年龄、手术出血量、手术时间及住院时间分别为 (61.3±8.5)岁、(246±180)mL、(141±36)min及(10.2±3.4) d,2组间差异并无统计学意义。此外,2组患者性别、年龄、症状持续时间等差异均无统计学意义(P > 0.05),见表1。纳入标准:(1)通过海南医学院第一附属医院影像(CT及MRI)检查诊断为脊髓型颈椎病的患者[17],同时病变范围均超过3个节段;(2)所有患者均接受C3至C7的SDCL手术减压;(3)所有手术均有一名高年资医师完成。排除标准: (1)患者临床症状及术后随访资料不完善;(2)外伤、肿瘤及畸形等颈髓受损。
表 1 2组患者基本资料($\bar x \pm s $ )Table 1. Basic data of two groups ($\bar x \pm s $ )项目 预后良好组(n = 32) 预后不良组(n = 28) t/z P 性别(男∶女) 18∶14 15∶13 0.483 0.674 年龄(岁) 63.5 ± 10.2 61.3 ± 8.5 0.329 0.442 术中失血量(mL) 238 ± 155 246 ± 180 −0.378 0.538 手术时间(min) 136 ± 38 141 ± 36 −0.814 0.315 住院时间(d) 9.8 ± 2.6 10.2 ± 3.4 −0.728 0.414 症状持续时间(月) 51.4 ± 74.6 63.8 ± 78.5 2.672 0.061 随访时间(月) 18.8 ± 13.1 17.9 ± 15.4 0.621 0.328 1.2 手术方法
全身静脉麻醉后患者取俯卧位,常规消毒铺巾。随后取颈后路正中切口,暴露C2至C7棘突、椎板及关节突。咬除C2至C7棘突、棘上韧带及棘间韧带,充分暴露其椎板及侧块。使用高速磨砖在C2至C7双侧椎板、侧块联合处依次磨去外层骨皮质及部分松质骨,留下内侧骨皮质,其中左侧磨去内层骨皮质,以临床症状轻的一侧为门阀、临床症状严重的一侧为门轴进行开门。完成单侧开门后,打开椎板去除硬脊膜、黄韧带及突出椎间盘组织。用Cenerpiece微型板将开门的椎板与对侧C2至C7椎体侧块固定,并在其椎板及侧块处各用2枚螺钉固定。确定开门减压彻底及固定牢固后,依次冲洗伤口、止血、消毒及缝合伤口。
1.3 评价标准
依据术前术后MRI、CT及X射线测量矢状面直径、颈椎曲率指数、活动度、椎管面积、颈脊髓面积(图1)。采用日本骨科协会(JOA)评分评价患者的临床疗效[18],记录术前及术后JOA评分,并根据公式计算JOA改善率[14],JOA改善率 = (术后JOA评分-术前JOA评分)/(17-术前JOA评分)×100%。JOA改善率 > 60%为预后良好,反之则为预后不良。
1.4 统计学处理
采用SPSS 26.0软件进行统计分析。计量资料用均数±标准差(
$ \bar x \pm s $ )表示。2组内术前术后JOA评分的比较采用配对t检验。2组间年龄、术中失血量、手术时间、住院时间、随访时间及解剖参数等计量资料的比较采用独立样本t检验,而2组间末次随访JOA改善率的比较则采用卡方检验。若为非正态分布,则使用Wilcoxon符号秩检验。单变量分析P > 0.05则不考虑进行多变量分析,而多变量分析则使用logistic回归分析,P < 0.05表示差异有统计学意义。2. 结果
2.1 术后解剖参数与疗效
预后良好组与预后不良组患者手术前后矢状面直径、椎管面积、颈椎活动度和颈脊髓面积改变量均有明显的增加(P < 0.05)。预后良好组术前、术后椎管面积(P = 0.030,P = 0.024)、门轴位置(P = 0.001)、颈脊髓面积改变量(P = 0.001)均明显大于预后不良组,2组间差异均具有统计学意义(图2)。但2组间手术前后矢状面直径及颈椎活动度的差异并无统计学意义(P > 0.05),见表2。此外,预后良好组与预后不良组患者术前、术后JOA评分差异均具有统计学意义(P < 0.05)。预后良好组患者术前、术后JOA评分均明显高于预后不良组,而2组末次随访JOA改善率分别为64.1%、42.0%(表3,图3)。随访期间所有患者均未发现钢板移位或断裂、螺钉松动和椎板重新闭合等并发症发生。
表 2 2 组患者解剖参数变化($\bar x \pm s $ )Table 2. Changes in anatomical parameters of the two groups of patients ($\bar x \pm s $ )项目 预后良好
组(n = 32)预后不良
组(n = 28)t P 门轴位置(宽:窄) 23:9 12:16 0.463 0.001* 椎管直径(cm) 术前 1.67 ± 0.15 1.65 ± 0.16 0.354 0.872 术后 2.54 ± 0.12 2.49 ± 0.18 0.696 0.786 改变量 0.87 ± 0.15 0.84 ± 0.18 0.424 0.374 C2~C7 Cobb(°) 术前 12.3 ± 6.8 13.5 ± 8.4 −0.852 0.682 术后 10.6 ± 7.3 11.8 ± 9.1 −0.744 0.583 改变量 −1.7 ± 7.1 −1.7 ± 8.8 −0.624 0.517 颈椎曲率指数 术前 0.12 ± 0.15 0.11 ± 0.10 0.711 0.632 术后 −0.04 ± 0.07 −0.02 ± 0.06 0.520 0.423 改变量 0.11 ± 0.08 0.09 ± 0.08 0.784 0.566 椎管面积(mm2) 术前 198 ± 33 177 ± 32 0.382 0.030* 术后 348 ± 49 325 ± 47 0.249 0.024* 改变量 150 ± 28 148 ± 27 0.399 0.090 颈椎活动度(°) 术前 43.6 ± 12.7 44.8 ± 13.2 −0.884 0.637 术后 28.1 ± 11.8 31.4 ± 11.9 −0.729 0.516 改变量 −15.5 ± 11.8 −13.4 ± 12.5 0.478 0.361 颈脊髓面积(mm2) 术前 105 ± 49 98 ± 44 0.539 0.422 术后 160 ± 78 133 ± 72 0.473 0.316 改变量 55 ± 41 35 ± 37 0.126 0.001* *P < 0.05。 表 3 2 组间术前术后 JOA 评分变化[($\bar x \pm s $ )/%]Table 3. Changes of JOA score between the two groups before and after operation [($\bar x \pm s $ )/%]项目 预后良好组
(> 60%,n = 32)预后不良组
(≤60%,n = 28)术前JOA评分 10.3 ± 2.3 8.8 ± 1.5 术后JOA评分 14.5 ± 1.1 12.2 ± 0.8 末次随访JOA评分 16.9 ± 1.4 12.5 ± 1.2 末次随访JOA改善率 64.1 42.0 注:2组内术前、术后JOA评分统计学意义分别为:t1 = 12.252,P1 = 0.007;t2 = 10.537,P2 = 0.011。 2.2 多因素分析结果
将术前术后JOA评分、术前术后椎管面积、门轴位置及颈脊髓面积改变量进行多因素Logistic回归分析。多因素分析结果显示,术前(OR = 6.924,P = 0.001)及术后JOA评分(OR = 22.000,P = 0.001)、术前椎管面积(OR = 2.518,P = 0.022)和颈脊髓面积改变量(OR = 5.513,P = 0.001)是影响SDCL术后预后的相关因素(表4)。
表 4 影响患者 JOA 改善率的相关因素Table 4. Related factors affecting JOA improvement rate of patients项目 b OR 95%CI P 术前椎管面积 1.035 2.518 1.863~2.020 0.022* 颈脊髓面积改变量 1.868 5.513 1.729~2.105 0.001* 术前JOA评分 2.153 6.924 8.769~9.690 0.001* 术后JOA评分 1.899 22 13.000~13.681 0.001* *P < 0.05。 3. 讨论
SDCL可连续多节段扩大颈椎椎管,增加颈脊髓的面积,现已成为治疗多节段脊髓型颈椎病的常用方法[9, 19]。据研究表明SDCL术后的神经功能改善程度与颈椎硬膜囊的横截面积密切相关[13]。但目前尚无相关研究SDCL术后狭窄节段颈脊髓面积改变量与术后患者远期临床预后的相关性。本研究通过多因素回归分析SDCL术后颈脊髓面积改变量与患者远期临床疗效的相关性,研究表明:SDCL术后患者的术前术后JOA评分、术前椎管面积和术后颈脊髓面积改变量可预测患者远期神经功能的恢复程度。
由于脊髓在椎管内有一定的活动空间,导致部分患者在脊髓压迫早期并无明显的感觉或运动功能障碍。因此单纯依靠脊髓型颈椎病患者的临床症状持续时间并不能够准确的预判患者的脊髓压迫程度。而Yuan等[20]通过对运动、感觉和膀胱功能的综合评估,发现术前JOA评分可以更加准确地反映脊髓压迫的严重程度。此外,Zhang等[21]研究表明,颈椎椎板成形术后预后良好的患者术前JOA评分平均为(10.3±0.2),而预后较差组术前JOA评分(8.4±1.7)。该研究认为术前JOA评分较高的患者术后神经功能恢复程度高,可获得良好的临床疗效。与此同时,Hou等[22]在椎板成形术治疗颈椎后纵韧带骨化的临床疗效中报道,颈椎椎管狭窄程度高于50%的患者,术前及术后末次随访JOA评分分别为(9.8±1.9)、(11.3±3.1),而狭窄程度小于50%的患者,术前及术后末次随访JOA评分分别为(11.4 ± 2.0)、(14.7±2.7)。在本研究中,笔者同样发现相比于术前JOA评分较低的患者,术前JOA评分高的患者末次随访JOA的改善率更高,术后可获得令人满意的远期临床疗效。术后JOA评分虽然能够反映患者的预后,但部分研究发现如患者术前JOA评分较低,即使术后JOA评分相同,其预后也比术前JOA评分高的预后较差。术前JOA评分反映的是术前脊髓损伤的程度,术前JOA评分低意味着脊髓损伤严重,而脊髓的损伤是不可逆转的,因此即使患者术后JOA评分相同,术前JOA评分低的患者术后临床症状改善程度依然较差。
由于颈椎管内脊髓受压导致神经缺血缺氧产生炎性因子刺激神经,从而引起患者术前出现患者神经功能的障碍,而单开门颈椎椎板成形术可对颈脊髓连续多节段减压,增大狭窄节段脊髓的面积,减轻狭窄节段椎管对脊髓神经的压迫,可长期为颈脊髓神经功能的恢复创造条件[23]。Mizutani等[16]研究表明,颈椎椎板成形术后颈脊髓面积改变量及脊髓形态可影响颈椎神经功能的恢复。同时,Takahashi等[24]研究也认为,伴有神经功能障碍的狭窄节段的脊髓面积在椎板成形术后颈脊髓面积的改变量与患者上肢功能远期疗效的密切相关。此外,Zhao等[25]在部分椎板切除及椎间孔减压联合内固定术治疗多节段脊髓型颈椎病是否可改善神经功能中报道,与术前相比,在颈椎部分椎板切除及椎间孔减压术后患者狭窄节段的脊髓面积明显增大,可显著促进患者神经功能的恢复。在我们的研究中,所有患者术后颈脊髓面积较术前均明显增大,而预后良好组患者术后脊髓面积改变量明显大于预后不良照组,多因素回归分析结果也表明颈脊髓面积改变量与末次随访时JOA改善率密切相关。因此术者可通过颈椎单开门椎板成形术后脊髓面积改变量预测患者远期神经功能的恢复程度。
颈椎管狭窄导致狭窄节段的椎管内面积变小,从而压迫患者脊髓和神经的有效活动空间,引起神经功能的障碍。因此,颈椎管面积也是影响患者神经功能恢复的主要因素之一。Yang等[26]通过术前MRI测量颈椎椎管面积来评估硬膜囊的压缩程度,研究表明脊髓型颈椎病患者术前狭窄节段的椎管压迫脊髓活动的空间导致患者出现神经功能的障碍,而在颈椎板成形术术后扩大狭窄节段的椎管面积,增加脊髓的活动空间,因此促进术后患者神经功能的恢复。同时,Subramaniam等[27]研究表明,为实现椎管充分减压,促进术后神经功能的恢复,颈椎管狭窄的患者椎板成形术后狭窄节段的椎管面积至少恢复到正常的58%。与此同时,Li等[28]利用MRI测量椎板切除术术后患者10年后的椎管及脊髓的距离,研究发现椎管狭窄部位的直径从(2.2±1.3) mm增加到(6.1±0.9) mm,而脊髓向后位移了(6.2±1.1) mm,末次随访JOA评分较术前明显改善。此外,Hamburger等[29]研究认为,颈椎椎板成形术后术后椎管横截面面积平均增加了(78.2%±55.9)%,而术后JOA评分较术前增加(3.7±2.2)分,术后患者获得良好的治疗效果。在本研究中,多因素回归分析显示术前椎管面积是影响患者术后预后的主要因素之一,术前颈椎管面积大的患者在SCDL术后可取得良好的预后。此外,单开门颈椎椎板成形术的门轴位置也会影响术后椎椎管面积。然而,本研究中单因素分析时门轴位置虽然会影响术后椎管的面积,但多因素分析结果显示术后椎管面积、门轴位置与SDCL术后末次随访JOA改善率之间并无相关性。由此可见,单开门颈椎椎板成形术中门轴的位置与术后椎管面积可能是末次随访时影响JOA改善率的混杂因素。因此术者在SDCL术中术者应尽可能避免过度的扩张椎管与门轴的位置,减少术后C5神经根麻痹的发生率。
本研究为回顾性研究,且研究样本量少,随访时间较短,后期需要设计严格的随机化前瞻性研究,并且加大研究样本量及更长的随访时间;此外,研究中测量脊髓的横截面积,但没有评估脊髓的形态,后期研究需增加患者的脊髓形态对末次随访时JOA改善率的影响才能获得更加可靠的数据。
综上所述,单开门颈椎板成形术术后颈脊髓面积改变量、术前颈椎管面积、及术前术后JOA评分与术后末次随访时JOA改善率密切相关。术者可依据SDCL术后颈脊髓面积改变量预判患者的远期疗效。
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表 1 2组患者基本资料(
$\bar x \pm s $ )Table 1. Basic data of two groups (
$\bar x \pm s $ )项目 预后良好组(n = 32) 预后不良组(n = 28) t/z P 性别(男∶女) 18∶14 15∶13 0.483 0.674 年龄(岁) 63.5 ± 10.2 61.3 ± 8.5 0.329 0.442 术中失血量(mL) 238 ± 155 246 ± 180 −0.378 0.538 手术时间(min) 136 ± 38 141 ± 36 −0.814 0.315 住院时间(d) 9.8 ± 2.6 10.2 ± 3.4 −0.728 0.414 症状持续时间(月) 51.4 ± 74.6 63.8 ± 78.5 2.672 0.061 随访时间(月) 18.8 ± 13.1 17.9 ± 15.4 0.621 0.328 表 2 2 组患者解剖参数变化(
$\bar x \pm s $ )Table 2. Changes in anatomical parameters of the two groups of patients (
$\bar x \pm s $ )项目 预后良好
组(n = 32)预后不良
组(n = 28)t P 门轴位置(宽:窄) 23:9 12:16 0.463 0.001* 椎管直径(cm) 术前 1.67 ± 0.15 1.65 ± 0.16 0.354 0.872 术后 2.54 ± 0.12 2.49 ± 0.18 0.696 0.786 改变量 0.87 ± 0.15 0.84 ± 0.18 0.424 0.374 C2~C7 Cobb(°) 术前 12.3 ± 6.8 13.5 ± 8.4 −0.852 0.682 术后 10.6 ± 7.3 11.8 ± 9.1 −0.744 0.583 改变量 −1.7 ± 7.1 −1.7 ± 8.8 −0.624 0.517 颈椎曲率指数 术前 0.12 ± 0.15 0.11 ± 0.10 0.711 0.632 术后 −0.04 ± 0.07 −0.02 ± 0.06 0.520 0.423 改变量 0.11 ± 0.08 0.09 ± 0.08 0.784 0.566 椎管面积(mm2) 术前 198 ± 33 177 ± 32 0.382 0.030* 术后 348 ± 49 325 ± 47 0.249 0.024* 改变量 150 ± 28 148 ± 27 0.399 0.090 颈椎活动度(°) 术前 43.6 ± 12.7 44.8 ± 13.2 −0.884 0.637 术后 28.1 ± 11.8 31.4 ± 11.9 −0.729 0.516 改变量 −15.5 ± 11.8 −13.4 ± 12.5 0.478 0.361 颈脊髓面积(mm2) 术前 105 ± 49 98 ± 44 0.539 0.422 术后 160 ± 78 133 ± 72 0.473 0.316 改变量 55 ± 41 35 ± 37 0.126 0.001* *P < 0.05。 表 3 2 组间术前术后 JOA 评分变化[(
$\bar x \pm s $ )/%]Table 3. Changes of JOA score between the two groups before and after operation [(
$\bar x \pm s $ )/%]项目 预后良好组
(> 60%,n = 32)预后不良组
(≤60%,n = 28)术前JOA评分 10.3 ± 2.3 8.8 ± 1.5 术后JOA评分 14.5 ± 1.1 12.2 ± 0.8 末次随访JOA评分 16.9 ± 1.4 12.5 ± 1.2 末次随访JOA改善率 64.1 42.0 注:2组内术前、术后JOA评分统计学意义分别为:t1 = 12.252,P1 = 0.007;t2 = 10.537,P2 = 0.011。 表 4 影响患者 JOA 改善率的相关因素
Table 4. Related factors affecting JOA improvement rate of patients
项目 b OR 95%CI P 术前椎管面积 1.035 2.518 1.863~2.020 0.022* 颈脊髓面积改变量 1.868 5.513 1.729~2.105 0.001* 术前JOA评分 2.153 6.924 8.769~9.690 0.001* 术后JOA评分 1.899 22 13.000~13.681 0.001* *P < 0.05。 -
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