人工颈椎间盘置换术需要关注的问题

人工颈椎间盘置换术作为治疗颈椎病的新方法,正逐渐成为基础和临床研究的热点。人工颈椎间盘置换术与颈前路椎间盘切除术及融合术相比最大的区别在于重建了颈椎的高度和生理曲度,最大限度地保留脊柱的生理运动功能的同时减少相邻节段的退行性改变。目前临床结果表明人工颈椎间盘置换术可成为替代颈前路椎间盘切除术及融合术的一种手术方式。然而,其特有的并发症以及假体本身存在的问题也逐渐暴露出来,如假体尚无法完全模拟人体椎间盘的生物学效应,以及包括手术方式与假体在内的其他因素。同时,如何预防并发症等问题有待解决,其疗效是否能够长期保证手术节段的活动度,减少相邻节段退变的设计初衷等问题越来越多地引起了学者们的关注。     

角度人工椎间盘置换后对相邻下位椎间隙应力的影响

目的：探讨带角度人工颈椎间盘置换后椎间隙及相邻椎间隙应力变化。方法：根据已有的测量结果,设计角度人工椎间盘。对已建立的C4,5两节段带椎间盘的正常颈椎有限元模型、C4,5置换0°椎间盘假体和置换10°椎间盘假体后的颈椎模型进行轴向加压、前屈/后伸、侧弯、扭转加载,对比观察C4,5椎间隙应力变化;对已建立的C4-C63节段带椎间盘的正常颈椎有限元模型、C4,5置换0°椎间盘假体和置换10°椎间盘假体后的颈椎模型同样方式进行加载,对比置换节段及相邻节段的椎间隙应力变化。结果：C4,5两节模型加载中,轴向加载、前屈/后伸时80 MPa/0°假体与80 MPa/10°假体等效剪应力（Se）大小近似,较正常颈椎增大,侧弯时80 MPa/0°假体Se与正常颈椎接近,80 MPa/10°假体Se较正常颈椎增大。扭转时加载时扭转切应力（Szx/Szy）80 MPa/0°假体和80 MPa/10°假体接近正常颈椎。在C4-C63节段模型加载时,C4,5椎间隙置换80 MPa/10°假体后,轴向加载、前屈后伸、侧弯时,相邻下位节段（C5,6）的椎间隙Se均减小,扭转加载时Szx/Szy接近正常颈椎模型。结论：10°椎间盘假体植入椎间隙对颈椎相邻节段的椎间隙应力影响小,接近正常颈椎间盘力学性能。     

人工颈椎间盘置换术治疗脊髓型颈椎病的疗效观察

目的 观察应用人工颈椎间盘置换术治疗脊髓型颈椎病的疗效.方法对20例脊髓型颈椎病患者24个椎间盘行Prestige LP人工颈椎间盘置换术.术后以Odom分级标准评价疗效,以JOA评分评价脊髓功能,以VAS评分评价颈、肩部及上肢疼痛情况.X线片测量假体椎间盘间隙角及颈椎过屈、过神位活动度,观察异位骨化、骨赘形成及假体松动等情况.结果 患者均获随访,时间30～48个月.患者神经功能均恢复满意.Odom分级评分：优18例,良2例.脊髓功能JOA评分与术前比较差异有统计学意义（P〈0.05）,颈、肩部及上肢VAS评分与术前比较差异均有统计学意义（P〈0.05）.假体活动度与上、下位相邻节段的活动度比较差异均无统计学意义（P〉0.05）.1例单节段于术后24个月发生异位骨化.未见假体移位、松动、下沉等并发症.结论 颈椎人工椎间盘置换患者术后恢复快,颈椎稳定性和活动度无明显受损,近期疗效满意.     

Bryan人工颈椎间盘置换术后颈椎应力变化的三维有限元分析

我们建立了三维有限元模型,于椎间隙植入Bryan人工颈椎间盘假体,通过力学分析方法评价人工颈椎间盘置换对手术节段及上、下邻近节段的活动及应力变化的影响.一、材料与方法1.CT扫描:选取1名行“Bryan人工颈椎间盘置换术( C5/6)”治疗的颈椎病患者为志愿者,分别于术前和术后6个月采用SIEMENS 64层螺旋CT扫描机进行扫描,层厚0.6mm,扫描范围包括C4～C7全部骨性结构、韧带、椎间盘及Bryan人工颈椎间盘假体.     

新型钛合金金属橡胶颈椎间盘假体生物力学分析

【摘要】 目的：评估新型钛合金金属橡胶颈椎间盘假体的生物力学性能。方法：特殊绕丝机制作新型金属橡胶颈椎间盘假体,电镜观察假体表面结构并对假体力学性能、疲劳特性进行测试;将24个新鲜羊颈椎依次按C4/5完整标本、髓核摘除、假体置换、椎间盘切除植骨融合内固定（ACDF）处理后,给予2.5Nm载荷,分别测量其在屈曲、后伸、左右侧屈及左右旋转时的位移,通过计算得出角度变化值,观察置换节段和相邻上下节段的运动范围（ROM）。结果：假体孔隙率为60%～80%,孔径大小90～500μm,弹性模量7MPa,疲劳试验（循环极限次数500×104次,极限载荷设置为200N）后未见假体断裂、高度降低。手术节段ROM测定显示,髓核摘除组各向ROM均显著大于完整组（P＜0.05）,ACDF组的各向ROM均显著小于完整组（P＜0.05）,而假体置换组各向ROM均与完整组无显著性差异（P＞0.05）。对于相邻上位节段,假体置换组各向ROM与完整组无明显差异（P＞0.05）,而ACDF组ROM则大于完整组（P＜0.05）。相邻下位节段,假体置换组前屈ROM与完整组相比无明显差异,后伸ROM小于完整组（P＜0.05）,侧屈、扭转时ROM较完整组增加（P＜0.05）,但变化幅度小于ACDF组（P＜0.05）。结论：钛合金金属橡胶人工颈椎间盘假体保留了手术节段活动度,置入后对相邻椎间节段活动度及力学影响小,理论上可以成为较好的颈椎间盘置换假体。     

颈椎全人工椎间盘置换术治疗颈椎间盘突出症1例报告

颈前路减压植骨融合固定术是治疗颈椎间盘突出症及颈椎病的常用手术方式，它可以同时进行脊髓及神经根减压和重建颈椎稳定性。但颈椎间隙融合后，邻近节段的应力集中，易导致相邻节段的椎间盘加速退变，部分病例需要再次手术。，为此我们应用颈椎全人工椎间盘假体治疗颈椎间盘突出症1例．取得了初步疗效，现报告如下。     

角度人工颈椎间盘置换对关节突应力的影响

目的探讨带角度人工颈椎间盘置换后关节突及相邻关节突应力变化。方法选择400名西北地区40岁以上人群颈椎侧位X线片,计算机辅助设计软件测量颈椎间盘角,设计10°人工颈椎间盘;对已建立的C4、C5两节段带椎间盘的正常颈椎有限元模型、C4、5置换0°椎间盘假体和置换10°椎间盘假体后的颈椎模型进行轴向加压、前屈/后伸、侧弯、扭转加载,对比观察C4、5关节突应力变化;对已建立的C4～C6三节段带椎间盘的正常颈椎有限元模型、C4、5置换0°椎间盘假体和置换10°椎间盘假体后的颈椎模型同样方式进行加载,对比置换节段及相邻节段的关节突应力变化。结果 C3～C7椎间盘角分别为:C3、4(9.97±3.64)°,C4、5(9.95±4.34)°,C5、6(8.59±3.75)°,C6、7(8.49±3.39)°,各椎间隙之间椎间盘角两两比较,C3、4与C4、5,C5、6与C6、7差异无统计学意义(P>0.05),其余各椎间隙之间差异均有统计学意义(P<0.05)。C4、C5两节段模型加载中,轴向加载下三者等效剪应力(Se)无明显差异;前屈/后伸时正常模型Se最大,10°假体置换组最小;侧弯时正常椎体Se最大,10°假体置换组最小;扭转时10°假体置换组更接近正常椎体生理状态力学特性。C4～C6三节段模型加载中,C4、5节段的关节突关节Se在轴向加载、前屈/后伸、侧弯时较正常椎体明显减小;扭转时减小不明显,接近正常状态。相邻下位节段C5、6关节突应力在轴向加载和侧弯时应力明显减小,扭转时应力减小较少,前屈/后伸时无明显改变,接近正常节段力学特性。结论 10°椎间盘假体植入椎间隙对颈椎相邻节段的关节突应力影响小,接近正常颈椎间盘力学性能。     

颈椎人工椎间盘置换术的研究现状

颈椎人工椎间盘置换术（artificial cervical disc replacement，ACDR），亦称颈椎间盘成形术（cervical disc arthroplasty，CDA）。随着人工髋、膝关节置换术取代了导致关节功能严重丧失的髋、膝关节融合术，且腰椎人工椎间盘广泛、成功运用于临床，为了解决颈椎前路减压植骨融合术由于融合节段运动功能丧失所造成的相邻节段的过度运动和应力集中而导致相邻节段退变加速，越来越多的科研人员及医务工作者投入到颈椎人工椎间盘置换术的研究之中。     

人工颈椎间盘置换术治疗颈椎病的中期疗效观察

目的:观察人工颈椎间盘置换术治疗颈椎病的中期临床效果。方法:2004年10月至2008年2月,对24例颈椎病患者共31个椎间隙行人工颈椎间盘置换术,其中脊髓型颈椎病21例28个椎间隙,神经根型颈椎病3例3个椎间隙;10例12个椎间隙应用Bryan假体,14例19个椎间隙应用Prodisc-C假体。术后随访24～65个月,平均39个月,定期对患者进行JOA评分和Oswestry颈椎功能障碍指数(ONDI)评定,并摄颈椎X线片测量置换节段及其相邻上下节段的活动度。结果:1例术后10个月手术节段椎体前缘骨质增生并融合,活动度丢失。其余患者随访期间置换节段稳定,颈椎生理弧度没有明显丢失;没有假体下沉和明显偏移;术后1个月、2年及末次随访时的JOA和ONDI评分与术前比较有统计学差异(P0.01),术后各时间点两两比较无统计学差异(P0.01)。术后1个月、2年及末次随访时置换节段及其相邻上下节段屈伸、左右侧屈活动度与术前比较无统计学差异(P0.01),术后各时间点两两比较亦无统计学差异(P0.01)。结论:人工颈椎间盘置换术后中期疗效满意,但仍然需要更长期随访结果来进一步评价其功能和对邻近节段的影响。     

Bryan人工颈椎间盘置换术的中期随访结果分析

目的 观察Bryan人工颈椎间盘置换术后临床和影像学结果以及相邻节段退变的情况.方法 回顾性分析术后随访时间超过2年的26例单节段置换患者的临床资料,临床效果采用JOA和Odom评分进行评定.采用x线片观察手术节段活动度和椎旁骨化.采用X线片和MRI观察对比相邻节段退变情况.术前X线片示置换节段的活动度为2°～12°,平均为6.9°.结果 (1)临床结果:18例脊髓型颈椎病患者随访时JOA评分平均16分,平均改善率84%,8例神经根型颈椎病患者随访时临床症状全部消失.Odom分级:优秀15例,良好7例,一般4例.(2)X线片:术后置换节段的活动度为1°～14°,平均7.8°;7例出现假体周围异位骨化,仅1例假体运动消失,其余6例平均活动度为5.3°.相邻节段椎间隙高度术后无明显变化.(3)MRI T2加权像:根据Pfirrmann椎间盘退变分级方法,相邻节段椎间盘的分级术后无明显加重表现;相邻节段黄韧带肥厚对椎管的侵占率术后无明显加重;但是上下相邻椎间盘侵占率均略有增加.结论 Bryan人工颈椎间盘置换术保留了置换节段的运动性,避免了相邻节段的加速退变,2年以上随访效果优良.     

人工颈椎间盘置换术后邻近节段退变情况的早中期随访

目的研究人工颈椎间盘置换术治疗颈椎病的临床疗效及邻近节段退变情况。方法 2008年1月-2010年10月,采用人工颈椎间盘置换术治疗颈椎病患者39例。其中男20例,女19例;年龄32～60岁,平均45.7岁。病程1个月～10年,平均30个月。其中脊髓型颈椎病26例,神经根型颈椎病11例,混合型颈椎病2例(神经根型加脊髓型)。单节段病变27例,双节段病变12例。使用Prestige假体9例、Prodisc-C假体4例、Discover假体26例。采用日本骨科协会(JOA)评分评价患者神经功能恢复情况,测量置换节段及邻近节段活动度(Cobb角变化),并采用Kellgren X线颈椎退变分级评估法对邻近节段颈椎间盘退变情况进行评价。结果所有患者均顺利完成手术,术后切口均Ⅰ期愈合。39例均获随访,随访时间12～36个月,平均23.1个月。末次随访时患者JOA评分较术前显著提高(P<0.05),置换节段及置换节段相邻上、下位节段活动度与术前比较差异均无统计学意义(P>0.05)。根据Kellgren X线椎间盘退变分级评价结果显示,末次随访时有5例患者出现退变情况改变,其中从无(0级)退变为轻度(1、2级)3例,由轻度1级退变到轻度2级1例,由轻度2级退变到中度(3级)1例,退变发生率为12.8%,但退变情况分级与术前比较差异无统计学意义(χ2=1.793,P=0.406)。术后15个月(32例患者)邻近椎间盘未发生退变情况。结论人工颈椎间盘置换术治疗颈椎病有良好疗效,可较好地保留置换节段及邻近节段活动度,并可能对邻近节段的椎间盘起保护作用。     

Disc replacement using Pro-Disc C versus fusion: a prospective randomised and controlled radiographic and clinical study

Anterior cervical discectomy and fusion (ACDF) may be considered to be the gold standard for treatment of symptomatic degenerative disc disease within the cervical spine. However, fusion of the segment may result in progressive degeneration of the adjacent segments. Therefore, dynamic stabilization procedures have been introduced. Among these, artificial disc replacement by disc prosthesis seems to be promising. However, to be so, segmental motion must be preserved. This, again, is very difficult to judge and has not yet been proven. The aim of the current study was to first analyse the segmental motion following artificial disc replacement using a disc prosthesis. A second aim was to compare both segmental motion as well as clinical result to the current gold standard (ACDF). This is a prospective controlled study. Twenty-five patients with cervical disc herniation were enrolled and assigned to either study group (receiving a disc prosthesis) or control group (receiving ACDF, using a cage with bone graft and an anterior plate.) Radiostereometric analysis was used to quantify intervertebral motion immediately as well as 3, 6, 12 and 24 weeks postoperatively. Further, clinical results were judged using visual analogue scale and neuro-examination. Cervical spine segmental motion decreased over time in the presence of disc prosthesis or ACDF. However, the loss of segmental motion is significantly higher in the ACDF group, when looked at 3, 6, 12 and 24 weeks after surgery. We observed significant pain reduction in neck and arm postoperatively, without significant difference between both groups (P > 0.05). Cervical spine disc prosthesis preserves cervical spine segmental motion within the first 6 months after surgery. The clinical results are the same when compared to the early results following ACDF.     

A prospective,randomised, controlled multicentre study comparing cervical disc replacement with anterior cervical decompression and fusion

Purpose

Total cervical artificial disc replacement (TDR) simulates normal disc structure, thus avoiding the drawbacks of anterior cervical decompression and fusion (ACDF). This prospective, randomized, controlled and multicentre study aimed to evaluate clinical and radiographic outcomes by comparing cervical disc replacement using Mobi-C disc prostheses with ACDF.

Methods

This prospective, randomized, controlled and multicentre study consisted of 111 patients undergoing single-level Mobi-C disc prosthesis replacement (TDR group, n?=?55) or ACDF (n?=?56) from February 2008 to November 2009 at 11 medical centres across China. Patients were assessed before surgery, at seven days postoperation and one, three, six, 12, 24, 36 and 48 months postoperation. Clinical and neurological outcome was determined by measuring the Japanese Orthopaedic Association (JOA) scores, visual analogue scale (VAS) and Neck Disability Index (NDI). Static and dynamic radiographs were obtained of the cervical curvature, the functional spinal unit (FSU) angle and range of motion (ROM) of the cervical spine, FSU angle and treated and adjacent segments.

Results

A total of 111 patients were included and randomly assigned to either Mobi-C disc prosthesis replacement or ACDF. JOA, VAS and NDI showed statistically significant improvements 48 months after surgery (P?p?>?0.05). ROM in the ACDF group was significantly reduced at one month and remained so throughout the follow-up. By 48-months, more ACDF patients required secondary surgery (four of 56 patients).

Conclusions

Although ACDF may increase the risk of additional surgery, clinical outcomes indicated that both Mobi-C artificial cervical disc replacement and ACDF were reliable. Radiographic data showed that ROM of the cervical spine, FSU angle and treated and adjacent segments were relatively better reconstructed and maintained in the Mobi-C group compared with those in the ACDF group.     

人工椎间盘置换术治疗跳跃型多节段颈椎病的中期疗效

 目的 评价 Bryan 人工间盘置换术治疗跳跃型多节段颈椎病的疗效。方法 回顾性分析 2002 年 2 月至 2012 年 5 月接受 Bryan 间盘置换术（Bryan 组）或颈前路减压植骨融合术（ACDF 组）治疗的跳跃型多节段颈椎病患者相关资料。临床功能评估采用日本矫形外科协会（Japanese orthopaedic association,JOA）评分、颈椎功能障碍指数（neck disability index,NDI）、疼痛视觉模拟评分（visual analoguc scale,VAS）,影像学评估采用颈椎矢状位曲度、颈椎整体活动度及中间节段活动度,并于末次随访时评估邻近节段退变情况。结果 49 例患者随访超过 24 个月,Bryan 组 18 例,ACDF 组 31 例。两组患者性别、年龄、疾病类型等人口学资料的差异无统计学意义。两组患者术后 JOA、NDI、VAS 评分均较术前有明显改善。两组间各时间节点比较仅末次随访时 VAS 评分的差异有统计学意义。Bryan 组术后轴性症状发生率、颈椎活动度和未手术节段活动度分别为 11.1%、35.5°±5.9°和 7.3°±1.4°,ACDF 组分别为 45.2%、24.5°±6.2°、10.1°±1.6°,差异均有统计学意义。Bryan 组患者邻近节段无明显退变,ACDF 组 2 例出现退变,但无需再次手术。结论 应用 Bryan 间盘置换术治疗跳跃型多节段颈椎病,可有效改善神经功能,保留颈椎整体活动度,减少未手术节段活动度的代偿性增加,从而降低邻近节段退变及轴性症状发生率。     

The Bryan cervical disc prosthesis. Preliminary clinical experience with nine implants

PURPOSE: After an anterior cervical discectomy, immobility at the fused level may increase stress on adjacent disc spaces and causes disc degeneration in 92% of the cases with clinical manifestations in 25.6% of the patients within 10 years. The cervical disk prosthesis may help to prevent this problem. The Bryan prosthesis (Medtronic Sofamor Danek) is currently available in France after a European pilot study. METHODS: Since January 2002, 8 patients (9 implants) (mean age: 35 years) were operated on with a prosthesis implantation for disc degeneration after an adjacent previous interbody fusion in 2 patients and for disc herniation or spondylosis in 6 patients. The prosthesis were implanted at the C4-C5 level (one patient), C5-C6 (four patients), and C6-C7 (four patients). Post-operative radiological evaluations with dynamic X-rays and clinical status (Odom questionnaire) were analyzed. RESULTS: Surgical procedures, which were longer than the classical technique, were uneventful. Radicular pain resolved after surgery with excellent results with the Odom's score. With a mean follow-up of 12 months, the prosthesis mobility was 8.9 degrees . But one fusion of an implant was encountered 6 months after implantation. CONCLUSIONS: The general follow-up for the Bryan(R) cervical disc prosthesis implantation is still too short (2 years) for a definitive evaluation. If clinical results on pain are as good as expected, long-term mobility of the prosthesis has to be checked, as it is the main advantage over classical anterior cervical discectomy with fusion. Patient selection has to be considered.     

Biomechanical testing of an artificial cervical joint and an anterior cervical plate

An in vitro biomechanical study was conducted to determine the effects of fusion and nonfusion anterior cervical instrumentation on cervical spine biomechanics in a multilevel human cadaveric model. Three spine conditions were studied: harvested, single-level artificial cervical joint, and single-level graft with anterior cervical plate. A programmable testing apparatus was used that replicated physiologic flexion/extension and lateral bending. Measurements included vertebral motion, applied load, and bending moments. Relative rotations at the superior, implanted, and inferior motion segment units (MSUs) were normalized with respect to the overall rotation of those three MSUs and compared using a one-way analysis of variance (P < 0.05). Application of an anterior cervical plate decreased motion across the fusion site relative to the harvested and artificial joint spine conditions. The reduced motion was compensated for by an increase in motion at the adjacent segments. Use of an artificial cervical joint did not alter the motion patterns at either the instrumented level or the adjacent segments compared with the harvested condition for all modes of testing.     

Bryan颈椎人工椎间盘置换术后5年随访结果

目的:观察Bryan颈椎人工椎间盘置换术后5年随访结果。方法:我院从2003年12月开展Bryan颈椎人工椎间盘置换术,术后达到5年的患者共70例,其中57例获得57～69个月(平均60个月)随访。单节段置换47例,双节段置换9例,3节段置换1例。C3/4 5例、C4/5 10例、C5/6 45例、C6/7 8例。术前和末次随访时进行mJOA、VAS、NDI评分,末次随访时进行Odom′s分级评估临床疗效;术前和末次随访时,在过伸过屈侧位X线片上测量置换节段活动度,在侧位X线片上采用McAfee异位骨化分级方法评定异位骨化情况,在MRIT2加权像上采用Miyazaki颈椎间盘退变分级方法评定相邻节段椎间盘退变情况,在MRI中矢状位T2加权像上测量相邻节段突出椎间盘对椎管的侵占率。结果:(1)mJOA评分术前为13.4±1.9分,末次随访时16.1±1.1分,平均改善率为75.0%;上肢痛VAS评分术前为3.3±1.9分,末次随访时0.9±1.2分;颈肩痛VAS评分术前为3.0±1.5分,末次随访时1.6±1.4分;NDI评分术前为14.8±8.6分,末次随访时5.7±4.2分;以上指标末次随访时与术前比较均有统计学差异(P<0.05)。末次随访时Odom′s分级优21例,良27例,可7例,差2例。(2)28例患者获得X线随访,术前置换节段活动度为6.9°±3.0°,末次随访时为7.2°±3.7°,无统计学差异(P>0.05);末次随访时,30个手术节段中12个(40%)出现异位骨化,其中3个(10%)节段丧失活动度。(3)25例患者获得MRI随访,末次随访时50个相邻节段中7个(14%)椎间盘退变分级加重1级,但无相关临床症状出现;相邻节段突出椎间盘对椎管侵占率的年度平均增幅为0.3%～0.5%。结论:Bryan颈椎人工椎间盘置换术后平均5年随访的临床和影像学结果满意,手术节段活动度得到较好保留,相邻节段退变发生率较低,无相邻节段疾病发生。     

Clinical and radiographic reports following cervical arthroplasty: a 24-month follow-up

We reviewed patients with cervical disc prosthesis replacement for single-level cervical disc disease to evaluate its clinical effect and maintenance of cervical spine motion. Fifteen patients underwent Bryan artificial cervical disc replacement and were followed-up for at least 24 months. No neurological or vascular complications were observed during or after operation. JOA, VAS, and NDI scores showed statistical significant improvement in our follow-up. The procedure achieved an 87% (13/15) satisfactory rate at 24-month evaluations according to Odom's criteria. The range of motion (ROM) of the cervical spine, treated segment, adjacent segment, and functional spinal unit (FSU) decreased at early follow-up, but they recovered to the preoperative level at 12- and 24-month follow-up. Also, preoperative lordosis of the cervical spine and FSU were not only maintained but also even improved during the 24-month follow-up. No obvious degeneration of adjacent discs were found at MRI. There were no cases of prosthesis subsidence or extrusion. The cervical disc prosthesis showed a good clinical outcome; it also restored ROM of the cervical spine and reestablished cervical curvature in our 24-month follow-up. But to be sure of its long term effect, a longer follow-up is needed.