Abstract
目的
回顾性比较颈后路单开门椎管扩大成形术所有手术节段使用钛板固定和交替使用钛板、缝线固定两种术式的临床和影像学结果。
方法
共入组67例患者,其中交替使用钛板、缝线固定组(A组)33例,所有节段使用钛板固定组(B组)34例。比较两组的基础临床数据和影像学资料,如椎管前后径(anteroposterior diameter,APD)、颈椎曲率指数(cervical curvature index,CCI)和开门角。
结果
(1)A、B两组间在手术时间、术中出血量、并发症率、术后住院时间、术前和末次随访时的视觉模拟评分(visual analogue scale,VAS)、日本骨科协会(Japanese Orthopedic Association,JOA)评分及JOA评分改善率上差异均无统计学意义(P>0.05)。(2)A、B两组间术前、术后和末次随访时的CCI、APD差异也无统计学意义(P>0.05)。术后B组C4、C6节段的开门角大于A组,差异具有统计学意义(P<0.05),而C3、C5、C7节段的开门角两组间差异无统计学意义(P>0.05);末次随访时两组间各节段的开门角差异无统计学意义(P>0.05)。(3)各组内术前、术后和末次随访时的CCI差异无统计学意义(P>0.05), 术后和末次随访时的开门角差异也无统计学意义(P>0.05),但各组内术后和末次随访时的APD大于术前APD,差异具有统计学意义(P<0.05)。(4)A组住院治疗费用低于B组,差异具有统计学意义(P<0.05)。
结论
两种单开门术式的临床效果和并发症率并无明显差异,但交替使用钛板、缝线固定的颈后路单开门椎管扩大成形术能降低医疗花费。
Keywords: 颈椎病, 椎板成形术, 治疗结果
Abstract
Objective
To retrospectively compare the effect of alternate levels miniplate and anchor fixation with the effect of all levels miniplate fixation in expansive open-door cervical laminoplasty (EOLP).
Methods
Patients with cervical spondylosis underwent EOLP between July 2015 and June 2016 were included in the study. There were 33 patients in the alternate group (alternate levels miniplate and anchor fixation group) and 34 patients in the miniplate group (all levels miniplate fixation group). Neurological function was evaluated with the Japanese Orthopedic Association (JOA) score and degree of pain was assessed with the visual analogue scale (VAS) score. Basic clinical and surgical data, complication rates and medical costs of the two groups were compared. In addition, radiological examinations were performed pre- and post-operatively and at the final follow-up. Relative imaging data such as anteroposterior diameter (APD), cervical curvature index (CCI) and open angle were collected and compared.
Results
(1) The mean follow-up time was 18.6 months in the alternate group and 18.9 months in the miniplate group. There were no significant differences in operation time, intraoperative blood loss, perioperative complication rates, post-operative hospital stays, VAS scores and neurological recovery rates preoperatively and at the final follow-up between the two groups. (2) Additionally, no obvious differences were observed about CCIs and APDs at the three follow-up time points between the two groups. Post-operative open angles at C4 and C6 in the alternate group were significantly smaller than those in the miniplate group. However, there were no significant differences in C3, C5 and C7 open angles between the two groups post-operatively. Notably, no significant differences were detected about the open angles at all levels between the two groups at the final follow-up. (3) When comparing radiologic data at different time points in each group, CCIs and open angles at each level had no significant differences, but APDs after surgery and at the final follow-up were significantly larger than pre-operative APDs. (4) Total costs in the alternate group were significantly lower than those in the miniplate group.
Conclusion
The two surgical methods showed almost the same neurological recovery rates and complication rates. However, use of alternate levels miniplate and anchor fixation in EOLP can reduce medical expenses.
Keywords: Cervical spondylosis, Laminoplasty, Treatment outcome
颈后路单开门椎管扩大成形术(expansive open-door laminoplasty,EOLP)最早由Hirabayashi等提出,至今已有40余年的历史[1],这一术式主要适用于多节段的脊髓型颈椎病[2]。缝线很早就被用于固定打开的椎板,但这一固定方式并不牢固,随着时间的推移,打开的椎板可能会重新闭合并造成神经脊髓压迫[3,4,5,6]。微型钛板是较新的椎板固定工具,能为开门的椎板提供坚强支撑,目前已经得到了广泛的应用[7,8]。钛板常规会被用于C3~C7的各个节段中,以阻止各节段椎板的再闭合。由于微型钛板价格高昂,为了降低医疗花费,同济医院骨科开始行交替节段钛板、缝线固定这一颈椎后开门术式以减少钛板的使用数量。本研究旨在比较交替钛板、缝线固定和所有节段钛板固定这两种颈后路单开门术式的临床和影像学效果。
1. 资料与方法
1.1. 一般资料
本研究纳入同济医院骨科自2015年7月至2016年6月共67位行EOLP的患者,所有患者的手术节段均为C3~C7,临床诊断依据病史、体格检查和影像学检查(如X线片、CT、MRI等)综合做出。入组排除了既往颈椎手术史、颈椎外伤、颈椎肿瘤、颈椎感染、开门节段不为C3~C7,以及颈椎后路联合颈椎前路、颈椎椎弓根钉和侧块螺钉固定的患者。术前谈话常规向患者阐释两种术式各自可能的优缺点,依据患者自身选择决定最终术式。最终,交替节段钛板、缝线固定(A组)和所有节段钛板固定(B组)的病例数分别为33例和34例。
1.2. 手术方法
所有手术均由具有15年以上执医经历的高年资医师完成。患者全身麻醉后取俯卧位,颈椎轻度屈曲。取颈后部正中切口,依次切开皮肤、皮下组织,沿棘突剥离椎旁肌暴露C3~C7椎板及侧块内缘,咬骨钳修剪C3~C7棘突至合适长度。椎板咬骨钳咬除C2/3及C7/T1间棘间韧带、黄韧带,显露硬膜。以患者症状和影像学压迫较重侧作为开门侧,对侧作为门轴侧。门轴侧使用高速磨钻在C3~C7椎板和侧块交界处开槽做门轴,开门侧使用高速磨钻在C3~C7椎板和侧块交界处切开全层椎板开门。缓慢掀开各节段椎板,切开开门侧C3~C7间黄韧带,小心分离硬膜外粘连。根据手术需要于各节段置入合适大小的微型钛板或锚钉丝线以维持开门。彻底止血,放置负压引流管一根,逐层缝合伤口。
根据术者的习惯与偏好,共两种钛板被使用,分别为强生公司的ARCH钛板和美敦力公司的Centerpiece钛板。A组在C3、C5、C7节段使用微型钛板固定,C4、C6节段使用螺钉吊缝线固定;B组在C3~C7所有节段均使用微型钛板固定。患者术后第2天开始行后颈部肌肉等长收缩训练并佩戴颈托下地活动,术后常规佩戴颈托4周。
1.3. 观察指标
观察比较的临床指标包括手术时间、术中出血量、术后住院天数、住院总费用、手术并发症,如脑脊液漏、C5神经根麻痹、伤口感染、轴性疼痛、内固定失败。采用日本骨科协会(Japanese Orthopedic Association,JOA)评分系统对神经功能进行评估,采用视觉模拟评分(visual analogue scale,VAS)系统进行疼痛程度评估。JOA评分改善度计算公式为:(末次随访JOA评分-术前JOA评分)/(17-术前JOA评分)×100%。分别比较两组术前和末次随访的VAS评分、JOA评分和JOA评分改善度。
轴性疼痛定义为后颈部或肩背部附属肌肉的疼痛,包括肩背部肌肉的僵硬、痉挛,末次随访VAS评分>3分的轴性疼痛定义为显著轴性疼痛[9]。C5神经根麻痹为术后出现的C5神经所支配的肌肉肌力减弱或运动不能。
搜集患者术前、术后(住院期间)和随访的影像资料,比较两组间术前、术后和末次随访各节段的椎管前后径(anteroposterior diameter,APD)、颈椎曲率指数(cervical curvature index,CCI)及术后和末次随访各节段的开门角,随后进一步比较各组内术前、术后和末次随访各节段的APD、CCI及术后和末次随访各节段的开门角。APD采用Wolf法在颈椎侧位片上测量(图1),CCI采用Ishihara法在颈椎侧位片上测量(图2)。开门角在CT或MRI轴位片上测量,开门角为门轴点到开门侧椎板终点的连线与颈椎冠状面间的夹角(图3)。
1.
颈椎侧位片上椎管前后径的测量(Wolf法)
Measurement of APDs according to Wolf’s method in the two groups before surgery, after surgery and at the final follow-up
A-C, lateral X ray images of a 50 years old male patient in group A; D-F, lateral X ray images of a 55 years old female patient in group B.
2.
颈椎侧位片上采用Ishihara法测量颈椎曲率指数
CCIs were measured as described by Ishihara
A, before surgery; B, after surgery; C, at the final follow-up.
3.
CT轴位片(C6节段)上测量颈椎开门角
Measurement of open angles at C6 with axial CT scans
A, before surgery; B, after surgery; C, at the final follow-up.
1.4. 统计学分析
采用SPSS 24.0进行数据分析,定量资料以均数±标准差表示。卡方检验用于比较两组间性别组成、术后并发症的差异,独立样本t检验用于两组间其他连续性变量的比较,采用配对样本t检验行组内前后比较。P<0.05为差异有统计学意义。
2. 结果
2.1. 临床结果
共67例患者纳入研究,其中男性52例、女性15例,平均年龄(53.4±10.8)岁。A组平均随访时间为18.6月,B组平均随访时间为18.9月。两组间年龄、性别组成、手术时间、术中出血量和术后住院时间差异均无统计学意义(P>0.05,表1)。两组间术前和末次随访的VAS评分、JOA评分和JOA评分改善率差异均无统计学意义(P>0.05,表1)。A组医疗总花费低于B组,差异有统计学意义(P<0.05,表1)。
1.
A、B组临床数据比较
Comparison of clinical data between the two groups
| Items | Group A (n=33) | Group B (n=34) | P |
| VAS,visual analogue scale; JOA, Japanese Orthopedic Association. Data were expressed as x±s. | |||
| Age/years | 52.1±10.3 | 54.6±11.2 | 0.35 |
| Gender (male/female) | 23/10 | 29/5 | 0.13 |
| Operation time/min | 177.5±45.5 | 191.2±49.1 | 0.25 |
| Post-operation hospital stay/d | 7.9±2.3 | 8.8±2.0 | 0.08 |
| Blood loss/mL | 471.1±198.1 | 611.6±416.3 | 0.19 |
| VAS score | |||
| Before surgery | 2.0±2.8 | 1.4±3.0 | 0.45 |
| Final follow-up | 1.5±2.2 | 1.7±2.4 | 0.80 |
| JOA score | |||
| Before surgery | 13.3±3.4 | 14.5±2.1 | 0.11 |
| Final follow-up | 15.6±3.2 | 16.1±1.1 | 0.45 |
| Recovery rate/% | 55.6±65.2 | 44.2±49.2 | 0.45 |
| Medical cost/yuan | 107 707.2±10 915.3 | 154 489.6±11 920.9 | <0.001 |
A组JOA评分由术前的13.3±3.4升至末次随访的15.6±3.2, B组JOA评分由术前的14.5±2.1升至末次随访的16.1±1.1,各组末次随访和术前的JOA评分差异具有统计学意义(P<0.05)。
两组患者直至末次随访均未发现内固定松动或断裂等并发症。仅A组术后出现1例脑脊液漏患者,1周后拔除引流管并最终痊愈。术后仅A组1例出现伤口渗液,予以定期换药、预防感染等治疗后伤口愈合。A组术后共2例出现C5神经根麻痹,B组术后1例发生C5神经麻痹,嘱患者进行功能锻炼及营养神经药物治疗后,患者症状于术后3个月缓解明显。A组术后1例出现显著轴性疼痛,B组共4例发生显著轴性疼痛,予物理、药物治疗后,患者症状有所减轻,但直至末次随访,上述患者颈痛VAS评分仍大于3分。A、B组直至末次随访,均未有患者因为神经功能恶化而再次手术治疗。
2.2. 影像学结果
组间比较:两组间术前、术后和末次随访时的CCI及各节段的APD差异无统计学意义(P>0.05,表2)。A组术后C4、C6节段的开门角低于B组,差异具有统计学意义(P<0.05),但两组间C3、C5、C7节段的开门角差异无统计学意义(P>0.05);两组间末次随访时各节段的开门角差异无统计学意义(P>0.05,表3)。
2.
A、B两组间椎管前后径的比较(x±s)
Comparison of anteroposterior diameter between the two groups (x±s) /mm
| Segment | Pre-operation | Post-operation | Final follow-up | ||||||
| Group A | Group B | P | Group A | Group B | P | Group A | Group B | P | |
| C3 | 15.2±1.1 | 15.5±1.4 | 0.49 | 23.3±2.4 | 23.2±2.5 | 0.89 | 22.3±1.4 | 22.1±2.1 | 0.70 |
| C4 | 14.7±1.3 | 14.8±1.4 | 0.75 | 22.6±2.3 | 22.8±2.1 | 0.61 | 22.1±1.3 | 21.9±2.0 | 0.77 |
| C5 | 15.1±1.2 | 15.7±1.5 | 0.12 | 24.1±2.1 | 23.6±2.2 | 0.42 | 23.6±1.4 | 22.5±2.0 | 0.06 |
| C6 | 16.2±1.2 | 16.3±1.5 | 0.74 | 24.6±2.2 | 25.0±2.0 | 0.54 | 23.7±1.6 | 24.1±1.7 | 0.46 |
| C7 | 16.3±1.2 | 17.0±1.7 | 0.06 | 25.7±2.6 | 25.1±2.3 | 0.39 | 25.0±2.1 | 24.5±1.9 | 0.55 |
3.
A、B组两组间开门角的比较(x±s)
Comparison of open angles between the two groups (x±s) /(°)
| Segment | Post-operation | Final follow-up | ||||
| Group A | Group B | P | Group A | Group B | P | |
| C3 | 30.1±5.7 | 34.5±6.9 | 0.06 | 34.0±4.9 | 31.8±7.1 | 0.44 |
| C4 | 28.4±5.3 | 35.1±6.4 | 0.003 | 31.2±6.0 | 31.7±7.0 | 0.87 |
| C5 | 33.5±4.4 | 34.9±6.4 | 0.52 | 33.8±5.0 | 31.5±5.9 | 0.36 |
| C6 | 29.9±6.3 | 37.9±6.0 | 0.001 | 30.6±5.9 | 34.8±4.1 | 0.07 |
| C7 | 32.3±5.2 | 37.7±8.5 | 0.07 | 33.9±5.3 | 34.2±6.0 | 0.91 |
组内比较:各组内术前、术后和末次随访时的CCI间差异无统计学意义(P>0.05), 术后和末次随访时各节段的开门角差异也无统计学意义(P>0.05,表4)。各组术后和末次随访时各节段的APD均大于术前APD,差异有统计学意义(P<0.05),术后和末次随访间各节段的APD差异无统计学意义(P>0.05,表5)。
4.
A、B组各组内术后、随访时开门角的比较(x±s)
Comparison of open angles at different timepoints within each group (x±s) /(°)
| Segment | Group A | Group B | ||||
| Pre-operation | Follow-up | P | Post-operation | Follow-up | P | |
| C3 | 30.1±5.7 | 34.0±4.9 | 0.08 | 34.5±6.9 | 31.8±7.1 | 0.39 |
| C4 | 28.4±5.3 | 31.2±6.0 | 0.20 | 35.1±6.4 | 31.7±7.0 | 0.25 |
| C5 | 33.5±4.4 | 33.8±5.0 | 0.89 | 34.9±6.4 | 31.5±5.9 | 0.21 |
| C6 | 29.9±6.3 | 30.6±5.9 | 0.78 | 37.9±6.0 | 34.8±4.1 | 0.17 |
| C7 | 32.3±5.2 | 33.9±5.3 | 0.09 | 37.7±8.5 | 34.2±6.0 | 0.29 |
5.
A、B组各组内术前、术后和末次随访时APD的两两比较(x±s)
Comparison of APDs at different timepoints within each group (x±s) /mm
| Segment | Group A | Group B | ||||
| Pre-operation | Post-operation | Follow-up | Pre-operation | Post-operation | Follow-up | |
| *P<0.05, vs. pre-operation. | ||||||
| C3 | 15.2±1.1 | 23.3±2.4* | 22.3±1.4* | 15.5±1.4 | 23.2±2.5* | 22.1±2.1* |
| C4 | 14.7±1.3 | 22.6±2.3* | 22.1±1.3* | 14.8±1.4 | 22.8±2.1* | 21.9±2.0* |
| C5 | 15.1±1.2 | 24.1±2.1* | 23.6±1.4* | 15.7±1.5 | 23.6±2.2* | 22.5±2.0* |
| C6 | 16.2±1.2 | 24.6±2.2* | 23.7±1.6* | 16.3±1.5 | 25.0±2.0* | 24.1±1.7* |
| C7 | 16.3±1.2 | 25.7±2.6* | 25.0±2.1* | 17.0±1.7 | 25.1±2.3* | 24.5±1.9* |
3. 讨论
EOLP是椎间盘突出、后纵韧带钙化、先天性椎管狭窄等导致的多节段脊髓型颈椎病的重要减压术式[10]。许多研究显示,再关门是缝线固定EOLP术后的常见并发症,可能造成患者术后神经功能的恶化,甚至需再次手术治疗[3,4,5,6]。Chen等[4]定义连续两次随访时的Pavlov’s值减少10%以上为再关门,结果显示缝线固定术后再关门率为36.5%,术后3例患者(共23例)出现了椎板再关门引起的神经症状并再次手术。Lee等[6]分别用椎管前后径减少10%和开门角减少10°作为再关门的标准,最后测得缝线固定后再关门率分别为44.7%和22.7%。为了降低再关门率,至今已有多种改良固定方式被提出,如在开门椎板间植入自体骨块、羟基磷灰石撑开器、微型钛板、微型钛板联合异体骨等硬质材料[11,12,13], 其中,微型钛板具有支撑牢固、不易脱落等优点,目前使用最为广泛。Chen等[14]的回顾性研究中共有29位患者行微型钛板固定的EOLP, 术后未见再关门现象的发生。
由于微型钛板价格高昂,因此一些研究尝试改良术式以减少钛板的使用数量,以降低医疗花费。Wang等[15]尝试在C3、C5、C7节段采用钛板固定,C4、C6节段开门后旷置,利用椎间韧带连接维持术后旷置节段的开门,术后长达59.2个月的随访显示,末次JOA评分较术前JOA评分得到了显著改善[15];另一项研究进一步将该术式与所有节段钛板固定这一术式进行比较,发现前者虽然降低了医疗花费,但术后神经功能恢复不如后者,作者分析原因可能为术后C4、C6节段的再关门对神经形成了再次压迫[16]。Yang等[17]采用相同术式,影像结果显示术后C4、C6节段的APD和开门角小于C3、C5、C7节段,该影像结果与Wang等[16]的推测原因相吻合。
为了避免旷置节段术后的再关门,本研究在C3、C5、C7节段有坚强固定的基础上,在C4、C6节段使用缝线锚定螺钉固定,结果显示术后A组C4、C6节段的开门角小于B组,但两组间末次随访时的JOA评分及评分改善率并无明显差异。与Wang等[16]在C4、C6节段旷置不同,本研究在C4、C6节段使用缝线螺钉固定,起到了阻止上述椎板再关门的作用,这可能是造成最终临床结果不同的原因。研究表明,与缝线固定相比,所有节段钛板固定能更好地保持颈椎的前突曲线和活动度[4]。本研究中A、B两组在术前、术后和末次随访时的CCI差异均无统计学意义,表明两种术式对颈椎的短期稳定作用相似。
我们进一步比较了各组组内术前、术后和末次随访时的APD、CCI和开门角,发现各组术后和末次随访时的APD、开门角差异均无统计学意义,表明随着时间的推移,两种固定术式的椎板在术后均未发生明显的回弹。临床结果也与此相吻合,直至末次随访,各组均无因神经功能恶化而需再次手术治疗的患者。有研究表明,椎板再关门主要发生于术后6个月内,6个月后由于门轴侧骨性结构的愈合使椎板趋于稳定[18,19]。本研究随访时间远长于6个月,因此有理由推论,延长随访时间,两组再关门率也不会发生明显变化,但这一推论尚需更长时间的随访来证实。
轴性疼痛作为EOLP术后的常见并发症,病因仍不完全清楚。目前认为,颈椎后方肌肉韧带复合体的破坏、关节突关节的损伤和术前严重颈痛是发生术后轴性疼痛的可能原因[20,21]。有研究认为,保护C2和C7棘突上附着的肌肉或术后对肌肉附着点进行修复,能降低术后轴性疼痛的发生率[22,23]。本研究样本量较小,术后共5例患者出现显著的轴性疼痛,其中4例术前颈痛VAS评分为0分,1例术前颈痛VAS评分9分,术中也未对C7棘突和C2半棘肌附着点进行特殊保护,因此无法通过本研究探寻术后轴性疼痛的发生原因。C5神经根麻痹的原因目前也并不清楚,有研究认为可能与术前椎间孔狭窄、术后脊髓过度漂移、术中神经刺激等因素相关[24,25],因为同样的原因,本研究也无法找出术后C5神经根麻痹的相关危险因素。
综上,尽管本研究存在样本量小、随访时间偏短等缺点,但本研究通过对比颈后路单开门椎管扩大成形术中所有节段使用钛板固定和交替使用钛板、缝线固定两种术式,发现两者的临床效果和并发症率并无明显差异,且交替使用钛板、缝线固定能降低医疗花费。
Footnotes
The authors have declared that no competing interests exist.
作者已声明无竞争性利益关系。
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