Effect of intervertebral disc height on postoperative motion and clinical outcomes after Prodisc-C cervical disc replacement

Background contextCervical total disc replacement (TDR) is an emerging technology. However, the factors that influence postoperative range of motion (ROM) and patient satisfaction are not fully understood.PurposeTo evaluate the influence of pre- and postoperative disc height on postoperative motion and clinical outcomes.Study design/settingRetrospective review of patients enrolled in prospective randomized Food and Drug Administration (FDA) trial.Patient sampleOne hundred sixty-six patients with single-level ProDisc-C arthroplasty performed were evaluated.Outcome measuresROM and clinical outcomes based on Neck Disability Index (NDI) and Visual Analog Scale (VAS) were assessed.MethodsPreoperative and postoperative disc height and ROM were measured from lateral and flexion-extension radiographs. Student t test and Spearman's rho tests were performed to determine any correlation or “threshold” effect between the disc height and ROM or clinical outcome.ResultsPatients with less than 4 mm of preoperative disc height had a mean 1.8° increase in flexion-extension ROM after TDR, whereas patients with greater than 4 mm of preoperative disc height had no change (mean, 0°) in flexion-extension ROM (p=.04). Patients with greater than 5 mm of postoperative disc height have significantly higher postoperative flexion-extension ROM (mean, 10.1°) than those with less than 5 mm disc height (mean, 8.3°, p=.014). However, patients with greater than 7 mm of postoperative disc height have significantly lower postoperative lateral bending ROM (mean, 4.1°) than those with less than 7 mm disc height (mean, 5.7°, p=.04). It appears that the optimal postoperative disc height is between 5 and 7 mm for increased ROM on flexion extension and lateral bending. There was a mean improvement of 30.5 points for NDI, 4.3 points for VAS neck pain score, and 3.9 points for VAS arm pain score (all p<.001). No correlation could be found between clinical outcomes and disc height. Similarly, no threshold effect could be found between any specific disc height and NDI or VAS.ConclusionPatients with greater disc collapse of less than 4 mm preoperative disc height benefit more in ROM after TDR. The optimal postoperative disc height range to maximize ROM is between 5 and 7 mm. This optimal range did not translate into better clinical outcome at 2-year follow-up.     

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.     

Effects of a cervical disc prosthesis on maintaining sagittal alignment of the functional spinal unit and overall sagittal balance of the cervical spine

The object of this study is to review the early clinical results and radiographic outcomes following insertion of the Bryan Cervical Disc Prosthesis (Medtronic Sofamor Danek, Memphis, TN), together with its effect on maintaining sagittal alignment of the functional spinal unit (FSU) and overall sagittal balance of the cervical spine for the treatment of single-level or two-level symptomatic disc disease. Forty-seven patients with symptomatic single or two-level cervical disc disease who received the Bryan Cervical Artificial Disc were reviewed prospectively. A total of 55 Bryan disc were placed in 47 patients. A single-level procedure was performed in 39 patients and a two-level procedure in the other eight. Radiographic and clinical assessments were made preoperatively and at 1.5, 3, 6, 9, 12, and 18 and up to 33 months postoperatively. Mean follow-up duration was 24 months, ranging from 13 to 33 months. Periods were categorized as early follow up (1.5–3 months) and late follow up (6–33 months). The visual analogue scale (VAS), neck disability index(NDI), Odom’s criteria were used to assess pain and clinical outcomes. Static and dynamic radiographs were measured by hand and computer to determine the range of motion (ROM), the angle of the functional segmental unit (FSU), and the overall cervical alignment (C2–7 Cobb angle). With all of these data, we evaluated the change of the preoperative lordosis (or kyphosis) of the FSU and Overall sagittal balance of the cervical spine during the follow-up period. There was a statistically significant improvement in the VAS score from 7.0 ± 2.6 to 2.0 ± 1.5 (paired-t test, P = 0.000), and in the NDI from 21.5 ± 5.5 to 4.5 ± 3.9 (paired-t test P = 0.000). All of the patients were satisfied with the surgical results by Odom’s criteria. The postoperative ROM of the implanted level was preserved without significant difference from preoperative ROM of the operated level. Only 36% of patients with a preoperative lordotic sagittal orientation of the FSU were able to maintain lordosis following surgery. However, the overall sagittal alignment of the cervical spine was preserved in 86% of cases at the final follow up. Interestingly, preoperatively kyphotic FSU resulted in lordotic FSU in 13% of patients during the late follow-up, and preoperatively kyphotic overall cervical alignment resulted in lordosis in 33% of the patients postoperatively. Clinical results are encouraging, with significant improvement seen in the Bryan Cervical Artificial disc. The Bryan disc preserves motion of the FSU. Although the preoperative lordosis (or kyphosis) of the FSU could not always be maintained during the follow-up period, the overall sagittal balance of the cervical spine was usually preserved.     

Is cervical lordosis relevant in laminoplasty?

Background contextLaminoplasty aims to decompress the spinal cord and stabilize the cervical spine in patients with multilevel cervical lesions. Not every patient with cervical compressive myelopathy is a good candidate for laminoplasty. Most studies recommend that neutral or kyphotic alignments are contraindications for laminoplasty. However, cervical sagittal alignment does not have a strong and consistent effect on the clinical outcomes of laminoplasty. Moreover, many reports on the effect of cervical sagittal alignment did not designate the ideal definition of alignment and used different definitions of lordosis.PurposeTo identify the effect of preoperative cervical alignment according to two different definitions after midline splitting double-door laminoplasty.Study designRetrospective cohort study.Patient sampleFrom August 2008 to September 2010, 58 patients were diagnosed with cervical myelopathy and treated with midline splitting double-door laminoplasty.Outcome measuresThe clinical results were assessed with the modified Japanese Orthopedic Association (JOA) score, neck disability index (NDI), and visual analog scale (VAS) and were compared to analyze the rate of change between preoperative and postoperative values. Postoperative radiological results at the final follow-up examinations were compared between groups to obtain the change in range of motion and sagittal alignment.MethodThe effect of cervical alignment on JOA, NDI, and VAS scales and also on change of alignment and change of range of motion (ROM) at the final follow-up examinations was analyzed statistically between two groups according to two different definitions such as Toyama classification and Cobb angle.ResultsNo difference was found between the two groups according to Toyama classification in terms of the postoperative improvement rate of the modified JOA score (p=.086), decreasing rate of the VAS (p=.940) or NDI (p=.211), postoperatively. Additionally, no difference was found for the decreasing rate of ROM (p=.427) or sagittal alignment (p=.864) based on the radiological evaluation results. Also, there was no difference between two groups according to Cobb angle in terms of the modified JOA score (p=.743), VAS (p=.548), or NDI (p=.32), postoperatively. Additionally, no difference was found for the ROM (p=1.000) or sagittal alignment (p=.440) based on the radiological evaluation results.ConclusionsDespite nonlordosis cervical sagittal alignment, double-door laminoplasty would be effective for patients with cervical myelopathy because of cervical spondylotic myelopathy or ossification of the posterior longitudinal ligament. Furthermore, sagittal alignment is not the absolute and sole factor that surgeons should consider when determining the optimal treatment strategy.     

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.     

Prestige-LP人工椎间盘置换术治疗跳跃型颈椎椎间盘突出症

目的评价Prestige-LP人工椎间盘置换术治疗跳跃型颈椎椎间盘突出症的疗效。方法回顾分析2008年1月—2015年2月在本院接受人工椎间盘置换术治疗的29例跳跃型颈椎椎间盘突出症患者的临床资料。对所有患者均于术前、术后1周、术后3个月、术后6个月、术后12个月及末次随访时,采用生活质量量表(SF-36)评分、颈部疼痛视觉模拟量表(VAS)评分、日本骨科学会(JOA)评分、颈椎功能障碍指数(NDI)评估临床效果;采用颈椎正侧位及功能位X线片测量颈椎曲度,跳跃节段椎间角度、置换节段、跳跃节段的屈伸活动度(ROM)和椎间高度,以及C2~7屈伸ROM。结果所有患者随访6~82个月,平均25.1个月。所有患者的神经症状均明显好转,术后各随访时间点SF-36、JOA评分、VAS评分、NDI均较术前明显改善,差异具有统计学意义(P0.05)。术后3个月,跳跃节段屈伸ROM由术前的12.72°±3.80°增加到16.04°±3.17°(P0.05),后逐渐减小,至末次随访时接近术前水平。术后上、下置换节段的椎间高度较术前明显增加(P0.05)。所有患者末次随访时颈椎曲度、跳跃节段椎间角度、置换节段及C2~7 ROM与术前相比差异无统计学意义(P0.05)。结论 Prestige-LP人工椎间盘置换术治疗跳跃型颈椎椎间盘突出症能较好地保留置换节段、跳跃节段及颈椎整体的运动学特性,且术后并发症少,是一种安全有效的治疗选择。     

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.     

Comparison of clinical outcomes between cervical disc arthroplasty and anterior cervical discectomy and fusion for the treatment of single-level cervical spondylosis: a 10-year follow-up study

BACKGROUND CONTEXTThe theoretical advantage of cervical disc arthroplasty includes preserved motion at the cervical level, which may reduce degeneration of the adjacent segments. The long-term follow-up results are still controversial.PURPOSEThe present study aimed to retrospectively study the long-term efficacy and complications of cervical disc arthroplasty using a single commercially-available device in a single center.STUDY DESIGNThis was a propensity-score matched cohort study.PATIENT SAMPLEThis study enrolled 148 single-level cervical degenerative disease patients from January 2009 to March 2012. After 1:1 propensity score matching, 39 patients remained in the ACDF or ACDR groups.OUTCOME MEASURESThe outcome measures were neurological functions (Neck Disability Index (NDI) and Japan Orthopedic Association (JOA) scores), radiographic evaluations (cervical curvature, operative segment range of motion, degenerative condition of adjacent segments, heterotopic ossification (HO) of the surgical segment), and complications.METHODSNDI and JOA scores were used to evaluate patient neurological functions. Cervical curvature (C2-C7 Cobb angle) and operative segment range of motion (ROM) were compared between the two groups. Grading criteria for osteophyte formation were used to evaluate the degenerative condition of adjacent segments. HO after ACDR was graded according to the McAfee grading method.RESULTSThe average follow-up time was 119.3 ±17.2 months. Satisfactory improvements in neurological function were obtained for both the ACDR and ACDF groups. There were no significant differences in VAS or NDI scores between the two groups. In the ACDR group, the ROM of the operative segment increased from 6.7 ±4.3° before the operation to 8.9 ±3.5° on the second day after the operation (p<.001). The ROM of the operative segment was 8.1 ±4.0° at the 1-year follow-up, 7.2 ±3.6° at the 2-year follow-up, 5.7 ±4.5° at the 5-year follow-up and 4.3 ±3.9° at the last follow-up. ASD was more likely to develop in the caudal adjacent segments and progressed with the follow-up time. At the last follow-up, HO was present in 27 patients (69.23%), while high-grade HO (McAfee scores III and IV) was detected in 6 patients (15.38%).CONCLUSIONSThrough nearly 10 years of follow-up, ACDR was as effective as ACDF for treating single-level degenerative cervical disc disease. However, HO and the role of ACDR in the protection of ASD remains to be further observed and followed up.     

双插片自稳融合器选择性治疗创伤性颈椎间盘突出症初步报告

目的 :讨论单独应用双插片自稳式融合系统(double plate self locking interbody fusion device,ROI-C)前路手术治疗无椎节不稳、骨折或脱位的创伤性颈椎间盘突出症(traumatic cervical disc herniation,TCDH)的初期临床疗效。方法:自2011年12月至2013年12月采用前路切除受损椎间盘和突出物减压、ROI-C植骨融合固定选择性治疗17例TCDH,其中男12例,女5例;年龄24~41岁,平均32.9岁;单节段11例,双节段4例,三节段2例。观察比较手术前后日本骨科协会评分(Japanese Orthopaedic Association,JOA),视觉疼痛模拟评分(visual analogue scale,VAS),颈椎功能障碍指数(neck disability index,NDI),椎间高度和颈椎整体曲度变化,并依据Vaccraro标准判断植骨融合情况。采用Odom法进行疗效评定。结果:所有病例获得随访,时间12~33个月,平均18.5个月。JOA评分由术前的4.3±3.8增加至末次随访时的13.9±2.5;VAS评分由术前的6.5±2.2减少至末次随访时的1.0±0.9;NDI由术前的(38.2±11.7)%减少至末次随访时的(8.7±3.4)%;末次随访与术前比较差异均有统计学意义(P0.05)。椎间高度和颈椎曲度分别由术前的(5.2±1.7)mm、(5.1±7.5)°增至末次随访时的(7.8±0.6)mm和(10.5±5.1)°,差异有统计学意义(P0.05)。术后出现声音嘶哑1例,吞咽困难2例,分别术后2周和术后3个月症状消失。术后6个月所有节段均获骨性融合,随访期间未发现ROI-C移位、下沉或断裂。按照Odom标准评判疗效,优13例,良3例,可1例。结论:单独使用ROI-C前路固定融合治疗无椎节不稳、骨折或脱位的TCDH是有效、微创和可靠的手术方法,具有并发症少、融合率高、疗效好的优点。     

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.     

腰椎融合联合Coflex动态固定手术治疗腰椎退行性疾病

目的：总结腰椎后路椎间融合术联合Coflex动态固定术治疗腰椎退行性疾病的临床疗效。方法：对2008年3月至2010年3月应用腰椎后路椎间融合术联合Coflex动态固定治疗的18例腰椎退行性疾病患者（均为双节段）的临床资料进行回顾性总结分析。男11例,女7例;年龄41～62岁,平均50.2岁。分析内容包括：ODI指数、腰痛和下肢痛的VAS评分,并通过腰椎动力位X线观察活动度（ROM）、椎间隙高度（DHI）的变化情况。结果：所有患者获得随访,时间6～30个月,平均12个月。在末次随访时,腰痛VAS评分、下肢痛VAS评分及ODI指数均较术前明显改善（P〈0.001）。腰痛VAS评分术前（7.20±0.90）分,末次随访（1.50±0.90）分;下肢痛VAS评分术前（5.20±0.90）分,末次随访（1.10±0.80）分。ODI指数术前（52.50±5.90）%,末次随访（15.90±5.80）%。Coflex置入节段的DHI术前0.23±0.05,术后0.35±0.06,末次随访0.33±0.04,椎间隙高度未见明显丢失。Coflex置入节段的ROM术前（8.90±1.80）°,术后降至（8.30±1.90）°,末次随访（8.10±1.80）°,与术前差异无统计学意义（P=0.19）,Coflex置入节段活动度未见明显改变。L2-S1ROM术前为（20.20±5.60）°,术后（14.40±5.70）°,末次随访（15.50±5.20）°,与术前比较有统计学差异（P=0.01）。结论：腰椎后路椎间融合术联合Coflex动态固定治疗双节段腰椎退变性疾病能取得满意的中短期临床疗效,但没有充分证据证明这项技术优于多节段融合术。手术适应证的合理选择十分重要。     

零切迹自稳型颈椎融合器治疗双节段脊髓型颈椎病的中期临床疗效

目的评价应用零切迹自稳型颈椎融合器(ROI-C)行颈前路椎间盘切除融合术(ACDF)治疗双节段脊髓型颈椎病的中期临床疗效。方法 2012年3月—2014年3月,本院采用ROI-C行ACDF治疗的双节段脊髓型颈椎病患者22例,男16例,女6例;年龄45~76岁,平均58.1岁;C3/C4/C5 3例,C4/C5/C6 11例,C5/C6/C7 5例,C6/C7/T1 1例,C5/C6及C7/T1 1例,C3/C4及C5/C6 1例。采用疼痛视觉模拟量表(VAS)评分评价颈部疼痛程度,日本骨科学会(JOA)评分评价神经功能,Mac Nab标准评价疗效优良率。颈椎侧位X线片测量颈椎生理曲度和融合节段椎间高度,过伸过屈位X线片评价融合相邻节段的椎间活动度(ROM),并对术前及随访时数据进行比较。结果所有手术顺利完成。所有患者随访29~53个月,平均35.3个月。术后3个月VAS和JOA评分均较术前明显改善,差异有统计学意义(P0.05);末次随访时VAS评分和JOA评分较术后3个月进一步改善,且差异有统计学意义(P0.05)。术后3个月颈椎曲度和融合节段椎间隙高度均较术前明显改善,差异有统计学意义(P0.05);末次随访时与术后3个月时相比,差异无统计学意义(P0.05),颈椎曲度和融合节段椎间隙高度维持良好。末次随访时融合器沉陷率为11.4%。术后3个月相邻节段ROM较术前增加,差异有统计学意义(P0.05);末次随访时相邻节段ROM较术后3个月进一步增加,且差异有统计学意义(P0.05)。末次随访时有1例融合上位相邻节段发生椎间隙不稳,但无临床症状。根据Mac Nab标准,疗效优良率为90.9%。随访中未发生术后颈部轴性疼痛、融合器松动等其他并发症。结论应用ROI-C行ACDF治疗双节段脊髓型颈椎病中期随访临床疗效可靠,颈椎生理曲度和融合椎间高度得以有效维持。     

The long-term results of anterior surgical reconstruction in patients with postlaminectomy cervical kyphosis

Background contextPostlaminectomy kyphosis of the cervical spine is a challenging condition to treat because it has a combination of an exposed cord, progressive kyphosis, segmental instability, and anterior neural compression. The ideal mode of surgical correction remains controversial. In terms of surgical strategy, there are few large series that have reported the long-term results of anterior surgical treatment of this condition.PurposeThis study was designed to determine the long-term results and outcomes of anterior surgical treatment alone for the patients of postlaminectomy cervical kyphosis.Study design/settingThis is a retrospective review of prospectively collected data in an academic institution.Patient sampleThe sample comprises 23 patients who underwent anterior reconstruction surgery for the treatment of postlaminectomy kyphosis.Outcome measuresThe outcome measures were neck disability index (NDI), visual analog scale (VAS) for neck and arm pain, Nurick grades, kyphosis angles, fusion status, and complications.MethodsTwo independent spine surgeons reviewed the completed medical records and radiographs of 23 patients who had undergone multilevel anterior cervical hybrid decompression (corpectomy and discectomy) with instrumented fusions for postlaminectomy kyphosis by one surgeon at an academic institution. The clinical and radiographic outcomes were measured by NDI, VAS for neck and arm pain, Nurick grades, kyphosis angles, and fusion status at the time of preoperative, postoperative, and the last follow-up.ResultsThe mean follow-up was 44.5±31.0 months (range 24–120 months). The average preoperative kyphosis of 20.9° was significantly improved to a lordosis of 14.0° after surgery (p<.0001) and was maintained to a lordosis of 9.6° at the final follow-up (p<.0001). The average correction angle of kyphosis was 30.5±11.7°. The average preoperative, NDI, VAS, and Nurick grades were significantly improved at the last follow-up (all, p<.0001). The average levels of 0.9±0.7 corpectomy, 2.0±0.9 discectomy, and 3.8±1.4 anterior fusions were performed in each patient. Solid fusion was confirmed by computed tomography in all patients at a mean time of 3.8±1.2 months. There were six (26%) patients and seven (30.4%) complications: four (14.3%) graft-related complications (one implant displacement, one graft dislodgment, and one pseudarthrosis), one swallowing difficulty, one wound infection, one dura tear, and one pneumonia.ConclusionsOur data suggest that multilevel anterior surgical treatment using hybrid decompression (corpectomy and discectomy) combined with instrumented fusion yields acceptable clinical and neurological improvement and effective correction of cervical kyphosis. The techniques used also appeared to decrease the incidence of graft-related complications compared with a previous report by the same author.     

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.     

Prestige LP人工椎间盘置换治疗单节段颈椎病的近期疗效

目的：探讨应用Prestige LP人工椎间盘置换治疗单节段颈椎病的近期临床疗效。方法治疗单节段颈椎病患者15例,统计并分析患者术前和术后1、3、12个月随访时JOA评分、NDI脊髓功能评分、颈部及上肢疼痛VAS评分、置换节段活动度、颈椎运动范围、颈椎生理曲度等指标。结果神经系统症状均有不同程度改善,术后1、3个月及12个月时颈椎生理曲度较术前比均有显著性差异（P＜0.05）。术后1、3个月及12个月时颈椎的总活动度、置换节段活动度基本恢复至术前水平,二者无显著性差异（P＞0.05）。所有患者均未发生脊髓及神经根损伤、假体移位或异位骨化等并发症。结论应用Prestige LP人工椎间盘置换术治疗单节段颈椎间盘退变性疾病早期临床疗效良好,中远期疗效有待进一步观察。     

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.     

18例Charité人工腰椎椎间盘置换术后的中期随访结果

目的探讨Charité人工腰椎椎间盘置换治疗退行性腰椎椎间盘疾病及腰椎椎间盘突出症的效果及安全性。方法 2005年1～11月,采用Charité人工腰椎椎间盘置换术治疗18例腰椎椎间盘突出症患者,共计20个椎间隙。回顾性分析患者的临床资料,对比术前与术后以及术前与末次随访时的关节活动度（range of motion,ROM）、视觉模拟评分（visual analog scale,VAS）及Oswestry功能障碍指数（Oswestry disability index,ODI）,统计并发症。结果随访时间平均为45.6个月。术前平均ROM为8.1°,术后8.8°（P〉0.05）,末次随访8.4°（P〉0.05）;术前VAS平均72.8分,术后为32.2分（P〈0.01）,末次随访时为28.2分（P〈0.01）;术前ODI平均为57.0分,术后为31.4分（P〈0.01）,末次随访为27.6分（P〈0.01）。1例在随访半年时自述逆向射精。1例双节段置换的患者发生了异位骨化。无其他并发症。结论人工腰椎间盘置换术操作简便,疗效满意,并发症少,是治疗退行性腰椎间盘疾病和腰椎间盘突出症的一种安全、有效的方法 。     

Range of motion loss after cervical laminoplasty: a prospective study with minimum 5-year follow-up data

Background contextAlthough numerous studies have reported on the loss of flexion-extension range of motion (ROM) associated with laminoplasty, few have reported on the time course of this loss of motion for a long-term follow-up period.PurposeWe previously reported our early data on postlaminoplasty cervical ROM. In this article, we describe our minimum 5-year follow-up data to identify the time-dependent change in ROM after cervical laminoplasty.Study designA prospective cohort study.Patient sampleThe procedure was performed in 23 patients. Eighteen patients with a minimum 5-year follow-up were included in the study.Outcome measuresThe time-dependent neck ROM changes observed in the neutral, flexion, and extension radiographs were used to measure the radiological outcome. The Japanese Orthopaedic Association classification and a numerical rating scale of axial neck pain and arm pain were used to evaluate clinical outcome.MethodsTwenty-three patients who received unilateral open-door laminoplasties, including miniplate fixation over three levels, were serially evaluated at regular set intervals postoperatively. Eighteen patients with a minimum 5-year follow-up were included in the study. The mean follow-up period was 68.1 months (range, 60–78 months). Nine patients had ossification of posterior longitudinal ligament (OPLL) and nine patients had cervical spondylotic myelopathy (CSM). Enrolled patients were divided into subgroups (OPLL vs. CSM; autofusion vs. nonautofusion) to compare the ROM between the groups. We evaluated the time-dependent neck ROM changes by taking neutral, flexion, and extension radiographs preoperatively and at 1, 3, 6, 9, 12, 18, and 24 months postoperatively. Follow-up radiographs were taken annually after a 2-year follow-up.ResultsThe preoperative and 1-, 3-, 6-, 12-, 24-, 36-, 48-, and 60-month postoperative ROM figures were 39.9±11.2°, 35.0±9.2°, 33.0±11.0°, 30.1±10.4°, 25.8±13.1°, 24.7±10.0°, 23.8±6.5°, 24.6±8.3°, and 23.6±9.4°, respectively, and at the most recent follow-up, ROM was 24.5±10.1°. Thus, the mean ROM decreased by 15.4±8.4° (38.5%) by the last follow-up (p<.0001). In the OPLL group, we observed a more limited cervical ROM than in the CSM group (47.2% vs. 72.7%). As expected, in the laminar autofusion group, the ROM decreased significantly (55.6% decrease), whereas in the nonautofusion group, the ROM decreased less significantly (13.4% decrease) at the last follow-up. Postoperative axial pain did not correlate with the cervical ROM.ConclusionsThese results suggest that the loss of cervical ROM after laminoplasty is time-dependent, and patients with OPLL and laminar autofusion had less ROM. Postlaminoplasty ROM reduction can recover after several years, unless laminar autofusion occurs.     

Bryan颈椎间盘置换在治疗颈椎病中对颈椎曲度和置换节段的影响

目的:探讨Bryan颈椎间盘置换在治疗颈椎病中对颈椎曲度和置换节段的影响,并分析其临床疗效。方法:对2010年8月至2013年8月行Bryan人工颈椎间盘假体植入的49例患者进行回顾性分析,男26例,女23例;平均年龄48.5岁;神经根型21例,脊髓型16例,混合型12例;单节段置换21例,双节段置换28例。采用视觉疼痛模拟评分(visual analogue scale,VAS)比较手术前后的疼痛情况;根据日本骨科协会评估治疗分数(Japanese Orthopaedic Association Scores,JOA)和颈椎功能障碍指数(Neck Disability Index,NDI)评估神经功能改善状况;通过颈椎正侧屈伸位X线测量分析手术前后颈椎生理前凸曲度,脊柱功能单位(functional spinal unit,FSU)曲度,置换及邻近节段活动度,FSU活动度变化;采用Odom法进行疗效评定。结果:所有患者获得随访,时间18.5~37.3个月,平均33.1个月。VAS、JOA、NDI评分术前分别为7.08±1.55、5.2±1.9、39.96±7.06,术后3个月分别为3.76±2.33、13.2±1.2、25.20±6.64,末次随访分别为2.80±1.50、14.3±1.6、24.24±7.89,术后3个月和末次随访较术前明显改善(P0.05),末次随访和术后3个月比较差异无统计学意义。颈椎生理前凸曲度由术前的(10.64±4.26)°增加至末次随访时的(13.68±4.56)°,FSU曲度由术前的(5.40±0.41)°增加至末次随访时的(9.92±2.00)°(P0.05)。术前、术后3个月、末次随访颈椎活动度为(70.84±6.17)°、(60.00±6.58)°、(71.48±4.61)°,FSU活动度为(12.00±0.49)°、(9.36±0.26)°、(12.52±0.33)°,置换节段活动度为(10.48±0.67)°、(7.24±0.34)°、(9.28±0.36)°,置换上位节段活动度为(10.52±0.60)°、(8.60±0.30)°、(10.44±0.43)°,置换下位节段活动度为(8.48±0.40)°、(6.56±0.36)°、(9.60±0.39)°,术后3个月与术前比较差异均有统计学意义(P0.05),末次随访与术前比较差异均无统计学意义(P0.05)。术后发生咽部不适、声音嘶哑5例,均于术后2周内恢复正常。术后6个月发现异位骨化1例,术后12个月发现假体移位1例。按照Odom评定标准,优20例,良27例,一般2例。结论 :Bryan人工颈椎间盘置换术不仅有良好临床疗效,同时重建了颈椎和FSU前凸曲度,保留了颈椎置换节段活动度,恢复了颈椎整体生物力学功能。