Clinical and radiological results of total disc replacement in the cervical spine with preoperative reducible kyphosis

Purpose

To investigate the clinical and radiological results of total disc replacement (TDR) in the cervical spine with preoperative reducible kyphosis, and discuss when TDR is indicated for the patients with preoperative kyphosis.

Methods

Fifty-two patients who underwent single-level cervical TDR from June 2008 to May 2010 were included in this study. TDR was indicated for patients with preoperative lordosis or reducible kyphosis, and the patients were divided into a lordotic group (preoperative global angle of ≥0°) and kyphotic group (preoperative global angle of <0°). Clinical results were evaluated using the Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score and Neck Disablity Index (NDI). For radiological evaluation, the global and functional spinal unit (FSU) angles and the global and FSU range of motion were measured preoperatively and postoperatively.

Results

The mean NDI in the kyphotic group was significantly higher than that in the lordotic group preoperatively and at six months postoperatively, but the groups showed no significant differences in JOA score, VAS score and NDI at the two year follow-up. The mean global and FSU angles in the kyphotic group were significantly lower than those in the lordotic group preoperatively and at six months postoperatively, but they gradually improved postoperatively. The differences lost significance at the two year follow-up.

Conclusions

Postoperative cervical kyphosis had adverse effects on the NDI after TDR. Artificial discs, symptom relief, and neck functional exercises may contribute to correction of preoperative reducible kyphosis at different stages after cervical TDR. Preoperative reducible kyphosis should not be an independent contraindication for cervical TDR.     

Cervical arthroplasty with Discover prosthesis: clinical outcomes and analysis of factors that may influence postoperative range of motion

Purpose

The aim of this current study was to analyze the clinical outcomes after Discover cervical disc replacement and its effects on maintaining cervical lordosis and range of motion (ROM). The possible factors influencing postoperative ROM were analyzed.

Method

27 men and 28 women with a mean age of 46.4 ± 8.7 years were prospectively followed up for 2 years. Clinical outcomes were assessed using Japanese Orthopedic Association (JOA), Neck Disability Index (NDI), visual analog scale (VAS) and Odom’s criteria. Radiographic information including segment and overall alignment, functional spinal unit (FSU) and overall ROM, and disc heights were prospectively collected during the follow-up. The correlations between the postoperative FSU ROM at last follow-up and influencing factors were analyzed.

Results

Mean NDI, JOA and VAS scores showed statistical improvements at last follow-up. Anterior migration of the prosthesis was detected in six cases. Heterotopic ossification was observed in ten patients. Mean FSU angle, endplate angle of the treated level and mean overall cervical alignment were all improved significantly at last follow-up (P < 0.001). However, mean FSU ROM of the treated segment significantly decreased postoperatively (P = 0.008), while mean overall ROM showed no significant differences. A significant correlation was found between preoperative FSU ROM and postoperative FSU ROM by the Pearson correlation coefficient (r = 0.325, P = 0.034). Multiple linear regression analysis confirmed that preoperative FSU ROM contributed independently to a model with a coefficient of determination of 0.37 (P = 0.034).

Conclusions

In the 2 years follow-up, the Discover cervical disc arthroplasty has provided satisfactory clinical outcomes. It was able to substantially restore segment and overall cervical alignment while partially maintaining segment and overall cervical ROM. Additionally, we found that postoperative FSU ROM positively correlated with preoperative FSU ROM.     

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。     

Clinical and radiographic outcomes of dynamic cervical implant replacement for treatment of single-level degenerative cervical disc disease: a 24-month follow-up

Purpose

To determine the role of dynamic cervical implant (DCI) replacement for single-level degenerative cervical disc disease in Chinese patients.

Methods

Thirty patients with single-level degenerative cervical disc disease were prospectively enrolled between April 2010 and August 2010 (12 women, 18 men; mean age 56.5 years). All patients underwent anterior cervical decompression, DCI replacement, clinical and radiological assessments preoperatively and at 1, 6, 12, and 24 months postoperatively, and Japanese Orthopaedic Association (JOA), Visual Analogue Scale (VAS), Neck Disability Index (NDI), and Short Form 36 (SF-36) scores. Lateral neutral radiographs provided the intervertebral space height. Lateral dynamic radiographs were taken to measure the range of motion (ROM) of the cervical spine and functional spinal unit (FSU) of the treated segment. We compared the amount of motion of the adjacent vertebral endplate and the intrinsic motion of the implant and calculated a correlation analysis.

Results

DCI showed good clinical and radiographic outcomes. At the final follow-up, JOA, VAS, NDI, and SF-36 average scores improved significantly. The intervertebral space height increased slightly after operation and was maintained during follow up. The ROM of the cervical spine and FSU decreased at early follow-up, but recovered to the preoperative level within 1–2 years. There was a high index of linear correlation between the motion of the adjacent vertebral endplate and the intrinsic motion of the implant.

Conclusions

DCI provided elastic dynamic stability for the targeted segment, and restored and sustained intervertebral space height and ROM of the cervical spine.     

Clinical and radiological follow-up of single-level Prestige LP cervical disc replacement

Objective

To evaluate the clinical outcomes and radiographic results of patients who underwent single-level cervical arthroplasty using the Prestige LP.

Method

Thirty-one patients with single-level cervical disc disease received the Prestige LP disc replacement from June 2008 to December 2009. The neck disability index (NDI), Japanese Orthopedic Association score (JOA) and visual analogue scale (VAS) were used to assessed clinical outcomes pre-operatively and post-operatively at 24 months. The overall cervical alignment (C2–7 Cobb angle), the functional segmental unit (FSU) curvature, the range of motion (ROM) of treated and adjacent levels were measured, and the evidence of heterotopic ossification (HO) was observed from static and dynamic radiographs.

Results

There was a statistically significant improvement in the NDI from 20.2 ± 7.5 to 6.4 ± 3.5 (P < 0.000), JOA from 12.8 ± 2.2 to 16.6 ± 0.6 (P < 0.000), the neck VAS score from 4.1 ± 2.5 to 1.4 ± 1.1 (P < 0.000), the arm VAS score from 4.6 ± 2.5 to 0.7 ± 1.1 (P < 0.000). The post-operative overall cervical alignment (9.3° ± 7.2°), ROM of treated level (7.6°) and adjacent level (upper level 9.4° ± 3.1°, lower level 9.1° ± 3.5°) are well maintained. The FSU were 0.2° ± 5.4° and 1.9° ± 5.5° at pre-operation and final follow-up with statistical significance (P = 0.011). Heterotopic ossification was evidenced in five operated segment (16 %).

Conclusions

The Prestige LP disc arthroplasty maintains favorable clinical outcomes, preserves the overall cervical alignment, FSU curvature, ROM of treated level and adjacent levels.     

Bryan颈椎间盘置换术与颈前路减压椎间融合术术后疗效的系统评价

目的:收集并分析SCI收录的关于Bryan颈椎间盘置换术与颈前路减压椎间融合术(anterior cervicaldiseectomy and fusion,ACDF)术后疗效比较的文献,对Bryan颈椎间盘置换术和ACDF术后疗效进行系统评价.方法:检索Pubmed、Medline、Embase、Ovid、Cochrane Library等数据库.入选文献均为临床研究;各研究的干预组(治疗组)术式为Bryan颈椎间盘置换术,对照组术式为ACDF;治疗组和对照组例数均不小于10;术后疗效评价包括颈部功能残障指数(neck disability index,NDI),相应节段运动范围(range of motion,ROM)等常见指标.结果:共4篇文献符合纳入标准.纳入人数共588人,干预组303例,对照组285例;术后2年内NDI合并权重均差(weiishted meBJl difference,WMD)为-0.39(95%CI,-1.56-0.78),P>0.05.术后2年内相应颈椎节段运动范围(ROM)合并WMD值为8.95(95%CI,7.01～10.89),P<0.05.结论:Bryan间盘置换术在术后2年内保留颈椎节段活动方面优于ACDF,尚没有足够证据表明Bryan间盘置换术术后2年内NDI优于ACDF.     

颈人工椎间盘置换治疗单节段颈椎病的中期随访研究

目的观察颈人工椎间盘置换术(CTDR)治疗单节段颈椎病的中期临床疗效。方法回顾性分析2009年1月—2011年10月本院收治的随访4年的81例单节段退变性颈椎病患者临床资料,按照手术方式分为CTDR组(n=41)及颈椎前路椎间盘切除减压融合术(ACDF)组(n=40)。采用颈椎功能障碍指数(NDI)和日本骨科学会(JOA)评分进行功能评价,采用Mc Afee分级评定异位骨化情况,并进行组间比较。通过MRI进行影像学评估,比较2组手术节段、邻近节段活动度(ROM)和C_(2~7) Cobb角。结果两组患者术后NDI和JOA评分明显改善。术后1个月CTDR组NDI明显高于ACDF组,在工作、驾车和娱乐3个项目上差异均有统计学意义(P0.05),两组之间JOA评分改善差异无统计学意义(P0.05)。在上、下邻近节段ROM和C_(2~7) Cobb角方面,CTDR组术前、术后变化不明显;ACDF组上位邻近节段ROM术后明显增加,C_(2~7) Cobb角术后明显减小,与术前相比差异均有统计学意义(P0.05);CTDR组与ACDF组相比,术后上位邻近节段ROM及C_(2~7) Cobb角差异有统计学意义(P0.05)。CTDR组在末次随访时共有15例患者出现异位骨化,2例假体下沉,1例椎体前缘骨赘吸收。ACDF组无椎间融合器下沉、植骨不愈合、畸形愈合、内固定松动断裂等并发症发生。结论 CTDR在早期恢复独立生活能力方面优势明显,中期随访可较好维持颈椎生理曲度及置换节段ROM,减少相邻节段的异常活动,保护邻近椎间盘,但中期随访发现有异位骨化发生。     

Cervical kinematics and radiological changes after Discover artificial disc replacement versus fusion

Background contextThe cervical disc arthroplasty has emerged as a promising alternative to the anterior cervical discectomy and fusion (ACDF) in patients with radiculopathy or myelopathy with disc degeneration disease. The advantages of this technique have been reported to preserve the cervical mobility and possibly reduce the adjacent segment degeneration. However, no studies have compared the clinical outcomes and radiological results in patients treated with Discover artificial disc replacement to those observed in matched group of patients that have undergone ACDF.PurposeWe conducted this clinical study to compare the cervical kinematics and radiographic adjacent-level changes after Discover artificial disc replacement with ACDF.Study designAnalysis and evaluation of data acquired in a comparative clinical study.Patient sampleThe number of patients in the Discover and ACDF group were 149 and 196, respectively.Outcome measuresThe Neck Disability Index (NDI) and visual analog scale (VAS) pain score were evaluated. The range of movement (ROM) by the shell angle, the functional segment unit and global angles were measured, and the postoperative radiological changes at adjacents levels were observed.MethodsA total of 149 patients with symptomatic single or two-level cervical degenerative diseases received the Discover cervical artificial disc replacement from November 2008 to February 2010. During the same period, there were a total of 196 patients undergoing one or two-level ACDF. The average follow-up periods of the Discover disc group and ACDF group were 22.1 months and 22.5 months, respectively. Before surgery, patients were evaluated using static and dynamic cervical spine radiographs in addition to computerized tomography and magnetic resonance imaging. Static and dynamic cervical spine radiographs were obtained after surgery and then at 3- and 6-month follow-up. Then, the subsequent follow-up examinations were performed at every 6-month interval. The clinical results in terms of NDI and VAS scores, the parameters of cervical kinematics, postoperative radiological changes at adjacent levels, and complications in the two groups were statistically analyzed and compared. No funding was received for this study, and the authors report no potential conflict of interest–associated biases in the text.ResultsAlthough the clinical improvements in terms of NDI and VAS scores were achieved in both the Discover and ACDF group, no significant difference was found between the two groups for both single- (VAS p=.13, NDI p=.49) and double-level surgeries (VAS p=.28, NDI p=.21). Significant differences of cervcial kinematics occurred between the Discover and the ACDF group for both the single- and double-level surgeries at the operative segments (p<.001). Except the upper adjacent levels for the single-level Discover and ACDF groups (p=.33), significant increases in adjacent segment motion were observed in the ACDF group compared with the minimal ROM changes in adjacent segment motion noted in the Discover group, and the differences between the two groups for both single and double-level procedures were statistically significant (p<.05). There were significant differences in the postoperative radiological changes at adjacent levels between the Discover and ACDF groups for the single-level surgery (p<.001, χ²=18.18) and the double-level surgery (p=.007, χ²=7.2). No significant difference of complications was found between the Discover and ACDF groups in both single (p=.25, χ²=1.32) and double-level cases (p=.4, χ²=0.69).ConclusionsThe adjacent segment ROM and the incidence of radiographic adjacent-level changes in patients undergoing ACDF were higher than those undergoing Discover artificial disc replacement. The cervical mobility was relatively well maintained in the Discover group compared with the ACDF group, and the Discover cervical disc arthroplasty can be an effective alternative to the fusion technique.     

Discover人工颈椎间盘置换治疗颈椎病的初步应用

目的通过与颈前路减压植骨内固定术治疗患者比较,探讨应用Discover人工颈椎间盘置换治疗颈椎病的早期效果。方法回顾分析2010年3月-2011年3月24例符合选择标准的神经根型和脊髓型颈椎病患者临床资料,按收治时间分为颈前路减压融合组(融合组13例,2010年3月-2010年9月)和Discover人工颈椎间盘置换组(置换组11例,2010年9月-2011年3月)。两组患者性别、年龄、病程、病变分型、病变节段等一般资料比较,差异均无统计学意义(P>0.05),具有可比性。记录手术时间、出血量、术后并发症,采用日本骨科协会(JOA)改善率、颈椎功能障碍指数(NDI)、Odom’s评分评价疗效;置换组于手术前后X线片上测量置换及其邻近节段的过伸过屈、左右侧屈活动度,以及假体偏心距。结果两组患者术后症状均缓解,未出现明显并发症。患者均获随访,融合组随访时间12～18个月,平均15.3个月;置换组随访时间6～12个月,平均9.6个月。术后1、3、6个月置换组NDI均高于融合组(P<0.05),但JOA评分改善率比较差异无统计学意义(P>0.05)。末次随访时融合组Odom’s评分为优6例,良4例,可3例,优良率76.92%;置换组为优9例,良1例,差1例,优良率90.91%;两组比较差异无统计学意义(χ2=3.000,P=0.223)。术后置换组过伸过屈及右侧屈活动度于1个月时明显减小(P<0.05),之后逐渐恢复;左侧屈活动度呈先增加后减少趋势,其中3、6个月时较术前明显增加(P<0.05)。术后置换节段和上位节段左侧屈活动度大于右侧屈(P<0.05),且上位节段左、右侧屈活动度差约为置换节段的2倍;侧屈活动度差与假体偏心距成正相关(P<0.05),且假体偏向侧的侧屈活动度增大,对侧活动度减小。结论 Discover人工颈椎间盘置换术是一种简便、安全且能保留颈椎活动的手术,早期疗效较好。     

Is hybrid surgery of the cervical spine a good balance between fusion and arthroplasty? Pilot results from a single surgeon series

Purpose

Few studies have investigated the role of hybrid surgery (HS) that incorporates anterior cervical discectomy and fusion (ACDF) and artificial disc replacement (ADR) techniques. To our knowledge, this is the first study that provides a direct comparison of all three groups in terms of intra-operative parameters and outcomes with a minimum follow-up of 2 years.

Methods

Seven consecutive patients who underwent HS were matched with another seven patients who underwent ACDF and ADR based on levels of surgery. Prospective data on demographics, pre-operative and post-operative assessments, complications and functional scores (VAS, NDI, EQ-5D health score and index) were analysed using Mann–Whitney U test. Type I error was set at 5 %.

Results

Duration of surgery was significantly shorter for ACDF at 135 min (p = 0.025) compared with HS and ADR. ACDF also had greater blood loss when compared with ADR (p < 0.036). ADR has the shortest duration of hospitalization followed by HS and ACDF (p < 0.031). The HS group returned to work fastest (54 days) when compared with both ACDF (107 days) and ADR (73 days) with statistical significance seen between HS and ACDF (p = 0.035). Cervical range of motion (ROM) and functional scores did not show any significant differences.

Conclusion

HS is comparable to ACDF and ADR in terms of safety and feasibility. Findings of shorter in-hospital stay and earlier return to work in HS group may be further explored in large, randomised controlled trials.     

Clinical and radiological features of hybrid surgery in multilevel cervical degenerative disc disease

Purpose

Although several studies have established the safety and efficacy of cervical disc arthroplasty (CDA) as compared to anterior cervical discectomy and fusion (ACDF), few studies have investigated the role of hybrid surgery (HS) that incorporates ACDF and CDA techniques in multilevel cervical degenerative disc disease (MLCDDD).

Methods

This prospective study enrolled patients with MLCDDD who underwent HS. Twenty consecutive patients who underwent HS were compared with patients who underwent ACDF and CDA at the same level of surgery. Patients were followed up for more than 2 years. Intraoperative parameters, clinical features and outcome scores were recorded. Radiological assessments included overall range of motion (ROM), disc height (DHI), and changes in adjacent disc spaces.

Results

Duration of surgery was significantly shorter for ACDF compared with HS and CDA (P < 0.05). The VAS, SF-36, JOA, and NDI scores improved significantly after surgery in all the patients without significant differences among the groups. Cervical ROM increased significantly in CDA and HS groups as compared with ACDF-treated patients (P < 0.05). The mean DHI at the treated level was significantly restored after surgery in all the groups. The HS group returned to work faster (30 days) when compared with both ACDF (62 days) and CDA (65 days) (P < 0.05).

Conclusion

HS is an effective, reliable, and safe procedure for the treatment MLCDDD. Such a surgical construct is comparable to ACDF and CDA in terms of safety and feasibility. However, large, randomized controlled trials are warranted.

     

Bryan人工颈椎间盘置换术与椎间融合术治疗颈椎病的中期疗效比较

目的 分析对比Bryan人工颈椎间盘置换术与颈前路减压植骨融合术(anterior ceryical discectomy and fusion,ACDF)治疗颈椎病的中期疗效.方法 2003年11月至2004年2月,16例患者行Bryan人工颈椎间盘置换术(A组),35例患者行ACDF(B组),于术前、出院前、术后6周、3、6、12、24个月及随后每半年一次随访,通过日本矫形外科协会(JOA)评分、简明健康状况调查表(SF-36评分)、颈椎残障功能指数(neck disability index,NDI)评定治疗效果.同期摄X线片,检测病变节段的稳定性和活动度.结果 两组患者术中、术后均无严重并发症发生.所有患者均获得6年以上随访,平均73.5个月.A组术后无假体移位、脱落等并发症发生,1例发生自发融合;置换节段活动度与置换前活动度的差异无统计学意义(P＞0.05).B组术后6个月X线片示植骨全部达骨性融合.两组患者术后随访时临床症状均明显缓解,疗效满意.两组患者的JOA评分及SF-36评分、NDI,术后随访时均较术前有明显提高(P＜0.05).B组活动度较术前明显减小(P＜0.01),而A组手术前后差异无统计学意义(P＞0.05);两组术后活动度差异有统计学意义(P＜0.05).结论 Bryan人工颈椎间盘置换术疗效良好,同时还可保留颈椎病变节段活动度,减少轴性症状,为颈椎病治疗提供一种新的方法.

Abstract：

Objective To compare the clinical outcomes of Bryan disc replacement with anterior cervical discectomy and fusion (ACDF) in patients with cervical spondylopathy. Methods Sixteen patients underwent Bryan cervical disc replacement (A group), and 35 patients underwent traditional ACDF (B group) were included in the study. Patients were followed up at regular intervals. The JOA score, SF-36, neck disability index (NDI) score and the dynamic flexion-extension radiographs were used to evaluated the oucomes.Results All the patients were followed up for more than 6 years (mean, 73.5 months). There were no severe adverse events in both groups. In A group, there were no differences between postoperative and preoperative mobility of surgical segments (P＞0.05). All patients obtained bone fusions 6 month after surgery in group B.In both groups, the clinical symptoms relieved obviously after surgery. The postoperative scores of the JOA,SF-36 and NDI significantly improved compared with those of preoperative ones (P＜0.05). In B group, range of motion (ROM) was significantly decreased postoperatively (P ＜0.01); in A group, there were no significant differences between postoperative and preoperative ROM (P＞0.05). The difference between two groups regarding ROM was noted (P＜0.05). Conclusion The mid-term outcomes of Bryan cervical arthroplasty are satisfied. And the cervical arthroplasty which can maintain the mobility of the segment, and decrease the incidence of the postoperative neck axial symptoms is a viable alternative to cervical spondylopathy.     

Comparison of cervical kinematics between patients with cervical artificial disc replacement and anterior cervical discectomy and fusion for cervical disc herniation

Background contextAlthough anterior cervical discectomy and fusion (ACDF) is an effective treatment option for patients with cervical disc herniation, it limits cervical range of motion, which sometimes causes discomfort and leads to biomechanical stress at neighboring segments. In contrast, cervical artificial disc replacement (ADR) is supposed to preserve normal cervical range of motion than ACDF. A biomechanical measurement is necessary to identify the advantages and clinical implications of ADR. However, literature is scarce about this topic and in those available studies, authors used the static radiological method, which cannot identify three-dimensional motion and coupled movement during motion of one axis.PurposeThe purpose of this study was to compare the clinical parameters and cervical motion by three-dimensional motion analysis between ACDF and ADR and to investigate the ability of ADR to maintain cervical kinematics.Study designThis was a prospective case control study.Patient samplePatients who underwent ADR or ACDF for the treatment of single-level cervical disc herniation.Outcome measuresVisual analog scale (VAS), Korean version of Neck Disability Index (NDI, %), and three-dimensional motion analysis were used.MethodsThe patients were evaluated by VAS and the Korean version of the NDI (%) to assess pain degree and functional status. Cervical motions were assessed by three-dimensional motion analysis in terms of sagittal, coronal, and horizontal planes. Markers of 2.5 cm in diameter were attached at frontal polar (Fpz), center (Cz), and occipital (Oz) of 10–20 system of electroencephalography, C7 spinous process, and both acromions. These evaluations were performed preoperatively and 1 month and 6 months after surgery.ResultsThe ACDF and ADR groups revealed no significant difference in VAS, NDI (%), and cervical range of motion preoperatively. After surgery, both groups showed no significant difference in VAS and NDI (%). In motion analysis, significantly more range of motion was retained in flexion and extension in the ADR group than the ACDF group at 1 month and 6 months. There was no significant difference in lateral tilt and rotation angle. In terms of coupled motion, ADR group exhibited significantly more preserved sagittal plane motion during right and left rotation and also showed significantly more preserved right lateral bending angle during right rotation than ACDF group at 1 month and 6 months. There was no significant difference in other coupled motions.ConclusionThree-dimensional motion analysis could provide useful information in an objective and quantitative way about cervical motion after surgery. In addition, it allowed us to measure not only main motion but also coupled motion in three planes. ADR demonstrated better retained cervical motion mainly in sagittal plane (flexion and extension) and better preserved coupled sagittal and coronal motion during transverse plane motion than ACDF. ADR had the advantage in that it had the ability to preserve more cervical motions after surgery than ACDF.     

单节段Prestige LP人工颈椎椎间盘置换术在骨量减少颈椎病患者中的应用

目的 探讨骨量减少的颈椎病患者行单节段Prestige LP人工颈椎椎间盘置换术的安全性和有效性.方法 回顾性分析2012年2月—2017年6月本院采用Prestige LP人工颈椎椎间盘单节段置换术治疗的22例骨量减少的颈椎病患者临床资料.在术前,术后3 d、3个月、6个月、12个月及末次随访时采用日本骨科学会(JOA)评分评价患者神经功能,采用疼痛视觉模拟量表(VAS)评分及颈椎功能障碍指数(NDI)评估患者颈肩部疼痛及颈椎功能情况.在术前,术后3 d、3个月、6个月、12个月及末次随访时测量患者颈椎整体曲度、颈椎整体活动度(C2～7 ROM)、置换节段椎间角度、置换节段ROM(rROM)、置换节段椎间隙高度、置换节段脊柱功能单位(FSU)高度、邻近节段ROM(aROM)及邻近节段椎间隙高度等.观察并记录假体下沉、移位情况.结果 所有手术顺利完成.所有患者随访26～78个月,平均38.2个月.末次随访时所有患者JOA评分、VAS评分及NDI均较术前显著改善,差异有统计学意义(P<0.05).末次随访时置换节段椎间隙高度及FSU高度与术前相比显著增加,差异均有统计学意义(P<0.05).末次随访时颈椎整体曲度、C2～7 ROM、置换节段椎间角度、rROM、aROM及邻近节段椎间隙高度等与术前相比,差异均无统计学意义(P>0.05).至末次随访时,发生假体下沉3例,移位2例.结论 采用单节段Prestige LP人工颈椎椎间盘置换术治疗骨量减少的颈椎病患者安全有效,可维持满意的椎间隙高度和ROM,但需警惕假体下沉和移位等并发症.     

Analysis of factors that may influence range of motion after cervical disc arthroplasty

Background contextCervical artificial disc replacement is increasingly becoming popular among spine surgeons. Cervical disc arthroplasty aims to afford spinal stability and then balance this with flexibility. One of the fundamental benefits from performing cervical arthroplasty instead of fusion is preservation of motion in both the functional spinal unit (FSU) and the overall cervical spine. Eventually, preservation of segmental motion is believed to prevent the development of adjacent segment degeneration. But to justify its use, disc replacement prosthesis must demonstrate actual motion in vivo and preserve range of motion (ROM) after surgery as long as it allows. Without preservation of motion, disc prosthesis becomes just a functional arthrodesis equivalent.PurposeThe purpose of this study was to analyze the possible factors affecting cervical spine ROM after single-level cervical disc arthroplasty.Study design/settingThis is a retrospective radiological study of patients with symptomatic single-level cervical disc disorder who received the cervical disc prosthesis (Bryan Cervical Disc Prosthesis; Medtronic Sofamor Danek, Memphis, TN, USA).Patient sampleProcedure was performed in 39 patients.Outcome measuresThe outcome measures were statistical correlation of possible factors and ROM.MethodsWe investigated possible factors that could affect cervical ROM after surgical intervention using cervical disc replacement. For this, we focused on two main components, namely, patient factors and technical factors. First, we examined patient factors, such as age, sex, preoperative FSU ROM, and preoperative overall cervical spine (whole cervical spine) ROM. Second, we then investigated technical factors, such as the amount of bone resection, disc insertion angle, and disc insertion depth. Then, our study searched if there was any statistical correlation between these factors and the postoperative cervical ROM.ResultsSignificant correlation was found between the postoperative overall cervical spine ROM and preoperative overall cervical spine ROM (p<.0001, R²=0.9062). Postoperative FSU ROM is closely correlated to both the preoperative FSU ROM (p<.0001) and the disc insertion angle (p=.0097). However, no significant correlation was noted between age, sex, disc insertion angle, and disc insertion depth.ConclusionSignificant correlation was found between the postoperative overall cervical spine ROM and preoperative overall cervical spine ROM. Postoperative FSU ROM is closely correlated to both the preoperative FSU ROM and the disc insertion angle. Careful preoperative evaluation of the patient's radiographs and meticulous surgical technique during the surgical procedure could aid in achieving the goals and benefits of cervical disc arthroplasty.     

What are the associative factors of adjacent segment degeneration after anterior cervical spine surgery? Comparative study between anterior cervical fusion and arthroplasty with 5-year follow-up MRI and CT

Purpose

It is well known that arthrodesis is associated with adjacent segment degeneration (ASD). However, previous studies were performed with simple radiography or CT. MRI is most sensitive in assessing the degenerative change of a disc, and this is the first study about ASD by radiography, CT and MRI. We sought to factors related to ASD at cervical spine by an MRI and CT, after anterior cervical spine surgery.

Materials and methods

This is a retrospective cross-sectional study of cervical disc herniation. Patients of cervical disc herniation with only radiculopathy were treated with either arthroplasty (22 patients) or ACDF with cage alone (21 patients). These patients were required to undergo MRI, CT and radiography preoperatively, as well as radiography follow-up for 3 months and 1 year, and we conducted a cross-sectional study by MRI, CT and radiography including clinical evaluations 5 years after. Clinical outcomes were assessed using VAS and NDI. The fusion rate and ASD rate, and radiologic parameters (cervical lordosis, operated segmental height, C2-7 ROM, operated segmental ROM, upper segmental ROM and lower segmental ROM) were measured.

Results

The study groups were demographically similar, and substantial improvements in VAS (for arm) and NDI (for neck) scores were noted, and there were no significant differences between groups. Fusion rates were 95.2 % in the fusion group and 4.5 % in the arthroplasty group. ASD rates of the fusion and arthroplasty groups were 42.9 and 50 %, respectively. Among the radiologic parameters, operated segmental height and operated segmental ROM significantly decreased, while the upper segmental ROM significantly increased in the fusion group. In a comparative study between patients with ASD and without ASD, the clinical results were found to be similar, although preexisting ASD and other segment degeneration were significantly higher in the ASD group. C2-7 ROM was significantly decreased in ASD group, and other radiologic parameters have no significant differences between groups.

Conclusion

The ASD rate of 46.5 % after ACDF or arthroplasty, and arthroplasty did not significantly lower the rate of ASD. ASD occurred in patients who had preexisting ASD and in patients who also had other segment degeneration. ASD may be associated with a natural history of cervical spondylosis rather than arthrodesis.     

Clinical and radiographic results of Bryan cervical total disc replacement: 4-year outcomes in a prospective study

Introduction

Early results have indicated that the Bryan cervical total disc replacement (TDR) favorably compares to anterior cervical decompression and fusion, while it is associated with fewer complications and higher levels of satisfaction. In this study, we sought to prospectively report the midterm outcomes of the Bryan TDR.

Patients and methods

A total of 20 patients had performed their 4-year follow-up visit and had been assessed clinically and radiologically. Clinical outcomes (JOA, VAS, NDI, SF-36) and ROM measurements were investigated preoperatively and at 1 and 6 months, and 1, 2 and 4 years after operation. Complications were also investigated. Occurrences of heterotopic ossifications (HOs) and adjacent-level degeneration (ALD) radiographic changes were detected from 4-year follow-up X-rays.

Results

The mean JOA score, VAS score for arm and neck, NDI score and SF-36 score for PCS and MCS were reduced significantly at each postoperative time point when compared with the preoperative condition. The range of movement of the cervical spine, functional spinal unit, treated segment and the adjacent segment temporarily decreased at the early assessment, but all recovered to preoperative levels over a 6-month to 4-year time period. HO was evident in 6 of the 23 operated segments, which did not restrict the movement of the prosthesis. No obvious ALD was found on MRI. There were no cases of prosthesis migration, subsidence, loosening or wear.

Conclusion

The midterm outcomes demonstrated that the Bryan TDR maintains favorable clinical and radiological results, with preservation of movement and satisfactory clinical outcome. There were no serious complications or cases of prosthetic wear or failure. The long-term benefits are yet to be examined.     

人工颈椎椎间盘置换与颈前路减压融合术治疗脊髓型颈椎病的疗效分析

目的比较人工颈椎椎间盘置换术与颈前路椎间盘切除减压植骨融合术(anterior cervical discectomy and fu-sion,ACDF)治疗脊髓型颈椎病的临床疗效。方法回顾性分析本院收治的人工颈椎椎间盘置换术及ACDF治疗的脊髓型颈椎病病例。测量所有患者颈椎活动度(range of motion,ROM),置换节段及相邻节段的ROM,并行日本骨科学会(Japanese Orthopaedic Association,JOA)评分及Odom分级。结果所有患者术后JOA评分和Odom功能评定均得到显著改善。置换组术后颈椎ROM、置换节段及其邻近间隙平均ROM无明显改变,差异无统计学意义(P>0.05)。ACDF组患者中,术后颈椎ROM显著减小,邻近间隙ROM明显增大,差异有统计学意义(P<0.05)。置换组术后邻近节段的ROM明显小于ACDF组,差异有统计学意义(P<0.01)。结论人工颈椎椎间盘置换术能保持颈椎ROM,避免邻近节段退变,早、中期疗效满意,远期效果尚有待临床进一步研究。     

颈椎人工间盘置换与前路减压融合术治疗单节段颈椎间盘突出症的疗效

目的:探讨Mobi-C颈椎人工间盘置换(cervical artificial disc replacement,CADR)与传统颈椎前路减压融合术(anterior cervical decompression and fusion,ACDF)治疗颈椎间盘突出症的临床疗效。方法:对2009年6月至2012年6月收治的27例单节段颈椎间盘突出症患者进行回顾性分析,男18例,女9例,年龄30~62岁,平均46.7岁。其中12例采用CADR治疗(CADR组),15例采用ACDF治疗(ACDF组)。所有患者有颈肩部及上肢疼痛麻木,病程1~13个月,平均2.4个月。术前、术后1周、末次随访时均进行全面的临床评价和生活质量问卷调查。应用Odom标准评价术后疗效,采用视觉模拟疼痛量表(VAS)记录疼痛级别,用颈椎功能障碍指数(NDI)和健康状况调查问卷SF-36对患者生活质量进行综合评定。结果:27例患者无神经血管并发症发生,均获得随访,平均随访时间16个月(6~30个月)。术后1周CADR组优10例,良2例,ACDF组优5例,良10例,两组疗效差异有统计学意义(χ2=6.75,P=0.019);末次随访时CADR组优10例,良2例,ACDF组优12例,良3例,两组疗效差异无统计学意义(χ2=0.049,P=1.000)。术后1周及末次随访时两组患者的上肢VAS评分均明显缓解(P<0.05)。术后1周:CADR组颈部VAS评分由术前的3.58±0.79下降至0.58±0.51(P<0.05),NDI指数由术前的(23.42±6.36)分下降至(5.42±1.68)分(P<0.05),而ACDF组下降不明显。末次随访时:两组患者的颈部VAS评分、NDI指数及SF-36生活质量与术前比较均有明显改善(P<0.05)。结论:Mobi-C CADR保留了减压节段的运动,允许患者迅速恢复正常的活动,术后早期即可显示明显疗效,且疗效稳定维持,患者的生活质量明显提高。     

Bryan人工间盘置换与前路减压融合治疗颈椎退行性疾病的中期随访研究

 目的 评价人工椎间盘置换术治疗颈椎退行性疾病的中期疗效,并探讨其是否可以减少邻近节段退变的发生。方法 前瞻性对比分析接受颈椎人工间盘置换术(置换组,45例)与颈椎前路减压融合术(融合组,48例)治疗的颈椎退行性疾病患者的随访6年临床疗效和影像学资料。临床疗效评价指标为日本骨科协会评分(Japanese Orthopaedic Association Scores,JOA)、颈椎功能残障指数量表(neck disability index,NDI)和Odom评分。影像学评价指标为矢状位曲度、活动度、邻近节段退变。结果28例置换组患者和35例融合组患者完成随访。两组患者末次随访的JOA评分和NDI均较术前有明显改善,组间比较差异无统计学意义。92.9%的置换组患者和97.1%的融合组患者Odom评分获得很好或较好的结果。两组患者颈椎矢状位曲度末次随访较术前均得到保持。颈椎整体活动度置换组末次随访与术前无明显差异,而融合组则是明显降低。置换组置换节段活动度术前为9.5°±3.7°,术后3个月为7.0°±3.0°,末次随访为6.6°±4.1°,末次随访较术后3个月无明显改变。邻近节段退变评估采用侧位X线片和MRI T2加权像,置换组上、下邻近节段退变均明显少于融合组。结论 Bryan人工椎间盘置换术6年的随访结果基本满意,能更好地保留颈椎生理活动及生物力学环境,从而降低邻近节段退变的发生率。