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。     

颈椎不同位置下甲状软骨对应颈椎节段的影像学研究

目的 研究颈椎退变病人不同体位下的甲状软骨与颈椎节段的对应关系。方法 搜集2018年1月至2018年7月100例行颈前路手术病人的术前X线影像资料,测量甲状软骨前缘中点对应的颈椎节段,描述颈椎不同位置下对应节段的分布关系,并分析影响其变化的相关因素。结果 中立位状态下,甲状软骨对应的节段主要分布在C₅~C₆范围,占93.0％（93/100）;过伸位状态下,甲状软骨对应的节段主要分布在C_4/5~C_5/6范围,占82.0％（82/100）。影响甲状软骨对应节段的最主要因素是性别。颈椎过伸位下,男性病人甲状软骨对应节段主要分布在C₅和C_5/6,占78.6%（44/56）;女性病人甲状软骨的对应节段主要分布在C_4/5和C₅,占72.7％（32/44）;女性甲状软骨对应节段要高于男性。上述指标比较,差异具有统计学意义（P均＜0.05）。结论 颈椎不同位置下甲状软骨的对应节段存在差异,随着颈部的后伸运动,甲状软骨对应的颈椎节段呈上移的规律;甲状软骨的位置存在性别差异,女性甲状软骨对应节段的位置相对较高。     

颈椎终板Modic改变在脊髓型颈椎病例中的分布和相关因素分析

 目的 探讨颈椎终板Modic改变在脊髓型颈椎病例中的临床分布特点,并探讨其发生的相关因素。方法 选择2012年1月至2013年6月期间,行颈椎正、侧位X线和颈椎矢状位、轴位MR检查并确诊为脊髓型颈椎病患者共426例,回顾性分析颈椎矢状位及轴位MRI中存在Modic改变在人群、年龄、病程、椎间盘节段、颈椎曲度和椎间盘退变分级中的分布特点和其发生的相关因素。结果 426例共2556个颈椎椎间盘中54例(12.7％)69个椎间盘117个终板(2.3％)发生Modic改变。 Ⅰ型15例(3.5％),22个椎间盘42个终板(0.8％); Ⅱ型31例(7.3％),34个椎间盘61个终板(1.2％); Ⅲ型8例(1.9％),13个椎间盘14个终板(0.3％)。按各个椎间盘节段发病数统计,C_2-3 0个、C_3-4 5个、C_4-5 16个、C_5-6 26个、C_6-7 19个、C₇T₁ 3个,发病率分别为0、0.2％、0.6％、1.0％、0.7％和0.1％。Modic改变和椎间盘退变明显相关。40岁以上患者是Modic改变发生较多的年龄段。通过Binary Logistic检验逐步回归法得出回归方程为Y=-14.314+4.037D+0.784C+0.310L+0.203T +0.162A(Y为Modic改变、A为年龄、T为病程、L为椎间盘节段、D为椎间盘退变程度、C为Cobb角分组),P=0.001,EXP值:D=23.038,C=1.893,L=1.307,T=1.187,A=1.164。 结论 脊髓型颈椎病终板Modic发生与椎间盘退变、椎间盘节段、病程、年龄和颈椎曲度存在相关性,椎间盘退变是最重要的影响因素。Modic改变中 Ⅱ型最为多见,Ⅰ型次之,Ⅲ型最为少见,多发生于C_5-6椎间盘,40岁以上多发。     

颈椎人工椎间盘置换术患者选择与异位骨化形成的相关性分析

 目的 分析颈椎人工椎间盘置换术患者选择与术后异位骨化形成的相关性。方法 回顾性分析2003年12月至2008年12月,48例接受Bryan人工颈椎间盘置换术且随访时间超过5年的患者资料,男21例,女27例;年龄20~53岁,平均42岁;脊髓型颈椎病34例,神经根型颈椎病14例;单节段置换术38例,包括C_3-4 3例、C_4-5 5例、C_5-6 28例、C_6-7 2例;双节段置换术9例,包括C_4-5、C_5-6 4例、C_5-6、C_6-7 5例;三节段置换术1例（C_3-4、C_4-5、C_5-6）;共59个手术节段。在术后颈椎侧位X线片上使用McAfee分级法评价异位骨化形成。使用Logistic回归分析患者性别、术前手术节段活动度、置换节段脊柱功能单位曲度、置换节段与相邻节段椎间隙高度比值等因素与术后异位骨化形成的关系。对阳性结果及其选择阈值采用接受者操作特征（receiver operating characteristic, ROC）曲线及曲线下面积（area under the ROC curve, AUC）进行检验和量化分析。结果 48例患者术后均获得5年以上随访,随访时间60~120个月,平均70.3个月。术后59个节段中,20个出现异位骨化,发生率为33.9%（20/59）。患者性别、节段活动度、置换节段脊柱功能单位曲度和术前置换节段椎间隙高度这四方面因素中,仅术前置换节段与相邻节段椎间隙高度比值与术后异位骨化的形成具有显著相关性。通过ROC曲线分析该因素的AUC为0.813,95%置信区间为0.666~0.959,据此计算出病变节段与相邻节段椎间隙高度比值的临床最佳判断阈值为0.9。结论 患者选择相关临床因素中的术前置换节段椎间隙高度与术后异位骨化形成具有相关性;针对可变旋转中心的Bryan颈椎人工椎间盘假体,术前病变节段椎间隙高度较相邻节段丢失超过10%者不适合行人工椎间盘置换术。     

青年颈椎失稳临床症状及影像学表现探讨

目的：探讨以在读医学硕博研究生为代表的青年人群颈椎失稳相关临床症状及X线影像学特征。方法：自2021年9月至12月对91例在读医学硕博研究生进行调查研究,其中男45例,女46例;年龄22~30（25.30±2.18）岁。收集受试者颈椎病相关不适症状,并由检查医师对其进行颈肩部压痛点检查和颈椎正侧位及功能位X线片拍摄,并根据X线检查结果将受试者分为颈椎非失稳组和失稳组进行比较。结果：91例受试者中,共有50例颈椎失稳者,占受试者总数的54.90%;颈椎曲度异常者78例,占受试者总数的85.70%。在50例颈椎失稳受试者中,共有50例以椎体角度位移≥ 11°为诊断依据而被诊断为颈椎失稳,其中,C_3,4失稳者13例,C_4,5失稳者30例,C_5,6失稳者7例;共有5例以椎体水平位移≥ 3.5 mm为诊断依据而被诊断为颈椎失稳,其中,C_3,4失稳者1例,C_4,5失稳者4例。两组比较,失稳组颈痛、头痛、肩痛不适症状阳性表现人数明显多于非失稳组（P<0.05）;失稳组C_4,5棘突间隙、C_5,6棘突间隙、C₂-C₅棘突旁开2 cm和肩胛骨上角（肩胛提肌止点）位置压痛表现人数明显多于非失稳组（P<0.05）;失稳组颈椎曲度明显小于非失稳组（P<0.05）。结论：以在读医学硕博研究生为代表的青年人群颈椎失稳发生率较高,失稳者以椎体角度位移≥ 11°为诊断依据而被诊断为颈椎失稳为主,其失稳节段集中在C_3,4、C_4,5、C_5,6 3个节段,颈椎失稳的发生常伴随颈椎曲度的异常而出现,临床表现多见头颈部和肩部疼痛,尤其是失稳节段的颈部疼痛。     

常见颈椎人工椎间盘假体尺寸与国人颈椎解剖学参数的关系

目的 对比分析常见颈椎人工椎间盘假体尺寸与我国健康成人颈椎解剖学参数的关系,为国人颈椎椎间盘假体的设计提供参考。方法 2015年1月—2018年12月在泰州市人民医院接受颈椎CT平扫的健康成人130名,其中男78名、女52名,年龄为18.0 ~ 66.0（41.41±12.03）岁。使用影像存档与传输系统（PACS）对C₃/C₄/C₅/C₆/C₇节段的解剖结构进行测量,测量参数包括椎体终板前后径（AP）、椎间隙高度（DH）、椎体前缘高度（ADH）、椎体后缘高度（PDH）、椎体终板横径（ML）及钩突间距（IDUP）。分析不同节段、性别、年龄组各解剖学参数的差异,并与常见的8种假体尺寸进行对比分析。结果 共520个节段纳入分析,其中AP为（16.08±1.84）mm,DH为（5.73±1.00）mm,ADH为（3.88±1.11）mm,PDH为（2.83±0.94）mm,ML为（16.13±1.99）mm,IDUP为（23.68±2.55）mm,ML/AP为1.01±0.13。PDH在不同节段之间差异无统计学意义（P > 0.05）,其余各指标在不同节段之间的差异均有统计学意义（P < 0.05）;C₃/C₄和C₅/C₆节段的ADH,C₅/C₆和C₆/C₇节段的DH,C₄/C₅、C₅/C₆和C₆/C₇节段的PDH性别间差异无统计学意义（P > 0.05）,其余各节段的各指标性别间差异均有统计学意义（P < 0.05）;C₅/C₆和C₆/C₇节段的AP在不同年龄组间差异有统计学意义（P < 0.05）,其余各节段的各指标在不同年龄组间差异均无统计学意义（P > 0.05）。与常见的8种颈椎人工椎间盘假体尺寸的对比结果显示,假体AP、ML尺寸与研究对象椎体终板AP、ML测量值的匹配度不理想,假体高度与研究对象DH测量值匹配度较差。结论 常见的不同品牌假体尺寸与我国健康成人的颈椎解剖学参数匹配度不是很理想,未来可设计更符合国人解剖学特征的颈椎人工椎间盘假体。     

颈椎前路椎间盘切除融合术治疗神经根型颈椎病

目的 探讨颈椎前路椎间盘切除融合术（ACDF）治疗神经根型颈椎病（CSR）的临床疗效。方法 2017年6月—2019年6月,采用ACDF治疗CSR患者43例,患者病程为8~28个月,病变位于C_4,5节段12例、C_5,6节段14例、C_6,7节段11例、C₇~T₁节段6例。评估并比较术前及术后3、6个月颈椎功能障碍指数（NDI）及颈部和上肢疼痛视觉模拟量表（VAS）评分;测量并比较术前及术后3、6个月颈椎曲度（C_2-7 Cobb角）、椎间高度和颈椎活动度（ROM）,观察并发症发生情况。结果 所有患者术后颈椎曲度、NDI、颈部和上肢疼痛VAS评分均较术前改善,差异有统计学意义（P < 0.05）;椎间高度、颈椎ROM与术前相比,差异无统计学意义（P > 0.05）。发生脑脊液漏2例,术后血肿及感染2例。结论 ACDF治疗CSR可取得较好的疗效,其可改善颈椎曲度,恢复神经功能。     

后路单开门联合椎间孔切开术与前路减压融合术治疗混合型颈椎病的疗效比较

 目的 通过回顾性病例分析,评价单开门椎板成形联合椎间孔切开术(laminoplasty with foraminotomy, LF )与前路椎间盘切除减压融合术（anterior cervical discectomy and fusion,ACDF）治疗脊髓神经根型颈椎病的临床及影像学疗效。方法 自 2008 年 1 月至 2010 年 1 月,按照纳入及排除标准选取 68 例患者纳入研究,ACDF 组 33 例,LF 组 35 例,随访均超过 2 年。疗效评估采用日本骨科协会（Japanese Orthopedic Association,JOA）评分及改善率,影像学评估采用 X 线片测量颈椎曲度和颈椎活动度（range of motion, ROM）,末次随访时采用颈椎功能障碍指数量表（neck disabilitv index,NDI）评估两组患者颈肩部疼痛的改善程度。结果 ACDF 组手术时间平均 187 min、出血量平均为 127 ml,与 LF 组（154 min、235 ml）比较,差异均有统计学意义（t _手术时间=4.170,P=0.000;Z _出血量=-6.888,P=0.000）。术后两组下肢感觉改善率（ACDF 组 64.0%、 LF 组 66.0%）的差异有统计学意义（Z=-7.512,P=0.000）,而上肢运动、上肢感觉及下肢运动改善率的差异均无统计学意义。术后 3 个月时 ACDF 组出现 1 例植骨不融合,随访 2 年时 3 例出现邻近节段退变;而 LF 组未见并发症出现。末次随访时 ACDF 组在提物（Z=-3.947, P=0.000）及开车（t=-7.523,P=0.000）方面的 NDI 疼痛评分低于 LF 组。ACDF 组颈椎曲度由术前平均 13.7°增加至 16.2°,而 LF 组由 14.6°降至 13.3°（Z=-3.374,P=0.001）。两种术式均导致术后颈椎 ROM 下降（ACDF 组 14.8°、LF 组 16.5°）,但差异有统计学意义（t=-2.167,P =0.034）。结论 LF 在改善长节段颈椎间盘突出所致的颈椎髓性症状及根性症状方面与 ACDF 的临床效果相近,但具有手术时间短、手术技术相对简单、近期并发症发生率低等优势,是治疗混合型颈椎病安全、有效的手术方式。     

Bryan颈椎人工椎间盘置换术的长期疗效观察

目的 评估Bryan颈椎人工椎间盘置换术的长期疗效。方法 对2004年12月至2008年8月于我院行Bryan颈椎人工椎间盘置换术的20例病人进行回顾性分析,男15例,女5例,平均年龄为（43.85±3.70）岁,其中单节段9例,双节段11例,C_3/4 2例、C_4/5 9例、C_5/6 15例、C_6/7 5例。①收集并比较其术前、术后1周、术后2年及末次随访的改良日本骨科协会（modified Japanese Orthopaedic Association, mJOA）评估治疗分数、疼痛视觉模拟量表（visual analogue scale, VAS）评分、颈椎功能障碍指数（neck disability index, NDI）以及Odom''s分级。②通过其术前、术后早期及末次随访时的X线侧位片及颈椎过屈过伸位片,评估其颈椎曲度、颈椎活动度（ROM）。③MRI T2加权像上根据Miyazaki分级标准评估Bryan人工椎间盘置换术后邻近节段的退变情况。④通过X线片及CT片根据McAfee标准评价异位骨化的发生情况。结果 ①术前及末次随访时的mJOA评分分别为（13.30±2.83）分、（15.25±2.07）分,VAS评分分别为（4.10±3.81）分、（1.55±1.53）分,NDI分别为（11.45±9.52）分、（6.00±4.78）分,所有评价指标末次随访时较术前均有显著改善,差异均有统计学意义（P均＜0.05）。末次随访时Odom''s分级为优8例,良8例,可2例,差2例。②脊柱功能单位（FSU）曲度及C₂~C₇曲度：术前分别为2.33°±4.08°、18.78°±6.68°,术后早期为4.12°±6.43°、20.00°±9.98°,末次随访时分别为3.21°±6.56°、15.61°±6.73°。FSU ROM及C₂~C₇ ROM：术前分别为9.15°±2.80°、47.28°±9.75°,术后早期为9.27°±3.83°、40.81°±14.66°,末次随访分别为9.37°±3.97°、42.03°±10.97°。3个时间点的FSU曲度及FSU ROM比较,差异均无统计学意义（P均＞0.05）,但C₂~C_{7 ROM术后较术前明显减少,与邻近节段ROM变化趋势一致。末次随访时,43个邻近节段中46.5%发生邻近节段退变（adjacent segment degeneration, ASD）,以C5/6最为常见,但均无临床表现;末次随访时31个手术节段中有23例（74.2%）发生异位骨化,其中严重异位骨化（Ⅲ、Ⅳ级）发生率为22.6%,C5/6最为常见。结论 Bryan颈椎人工椎间盘置换术治疗颈椎退变性疾病可以取得持久稳定的临床效果,尽管异位骨化发生率较高,但大部分保留手术节段活动,同时邻近节段仍可见退变,但均无临床症状。}     

颈椎椎板成形术后脊髓后移的相关因素分析

 目的 探讨颈后路单开门椎板成形术后脊髓后移的影响因素及其规律。方法 2008年2月至2010年10月收治的压迫性颈脊髓病患者经筛选后43例纳入本研究,均接受C₃～C₇后路单开门椎板成形术,男32例,女11例;年龄33～78岁,平均57.9岁。脊髓型颈椎病伴发育性颈椎管狭窄30例,颈椎后纵韧带骨化症13例。门轴侧关节突螺钉锚定法21例,保留门轴侧肌肉韧带复合体的钛缆悬吊法22例。术前、术后3个月颈椎中立位MRI正中矢状面测量各节段代表脊髓及硬膜囊后移的参数：脊髓前缘后移,脊髓后缘后移,硬膜囊前缘后移,硬膜囊后缘后移;将齿突与T₁椎体后下角的连线定义为E线,其长度为E值,从每个基准点向E线作垂线,每个垂线段的长度为Px(x=1~6),得到代表每个节段局部曲度的参数(100×Px/E);以颈椎曲度指数 (curvature index, CI) 表示颈椎整体曲度。对以上参数进行线性相关分析。结果 硬膜囊前缘后移在不同水平无明显变化,脊髓前缘后移、脊髓后缘后移与硬膜囊后缘后移则随所处节段不同而相应发生变化,且三者的变化具有一致性。脊髓后缘后移最大值位于C_5,6水平,但C_5,6水平脊髓后缘后移与CI无相关性。相关分析表明脊髓后缘后移与硬膜囊后缘后移呈高度线性相关,与(100×Px/D)具有较低的相关性 。结论 颈椎单开门椎管扩大成形术后脊髓的后移程度与同水平硬膜囊的后移程度高度相关,与局部曲度相关性较弱,与颈椎整体曲度无相关性。     

颈椎动态稳定器治疗颈椎病的早期临床效果

目的观察应用颈椎动态稳定器（dynamic cervical implant,DCI）治疗椎间盘退变所致颈椎病的早期临床效果。方法 2010年4~6月,8例颈椎间盘突出症患者均行椎间盘切除、椎管减压后DCI置入。观察手术前后颈椎正侧位、过伸过屈侧位X线片,测量患者手术前后C2~7、置入节段和置入邻近节段的活动范围（range of motion,ROM）。采用视觉模拟评量表（visual analog scale,VAS）评分、患者满意度（patient satisfaction index,PSI）分别评价患者手术前后的症状改善情况和满意度。结果患者术后上肢VAS评分平均改善4.8分,颈部VAS评分平均改善4.6分,术后患者PSI平均为1.8,手术有效率为100%。颈椎C2~7的ROM减少15.76°±16.00°,差异有统计学意义（P〈0.05）;术后置入节段椎间隙的ROM减少2.14°±2.31°,差异有统计学意义（P〈0.05）;术后邻近节段的ROM减少1.18°±5.05°,差异无统计学意义（P〉0.05）。结论应用DCI治疗椎间盘退变所致颈椎病的早期疗效确切,能维持颈椎的稳定性并保留一定范围的生理活动度。     

Long-term flexion-extension range of motion of the prodisc total disc replacement

The rationale for total disc replacement is avoidance of the junctional degeneration seen after arthrodesis by preservation of segmental motion. To justify the use of disc prostheses, it is essential to document maintained range of motion (ROM) and sagittal alignment at long-term follow-up. This is a retrospective radiographic study of 42 patients who had placement of 58 first-generation Prodisc prostheses at a mean follow-up of 8.7 years. Flexion-extension ROM was measured by Cobb's method. Junctional levels were evaluated for junctional degeneration. Pre- and postoperative global and segmental lordosis were measured. Prognostic patient factors predicting ROM of <2 degrees were evaluated. We observed ROM of at least 2 degrees in 66% of Prodisc prostheses at 8.7-year follow-up, although ROM was less than that reported in asymptomatic normal individuals. Mean ROM for disc prostheses with motion was 7.5 degrees at L3-L4, 6.2 degrees at L4-L5, and 4.1 degrees at L5-S1. Mean ROM for all prostheses was 3.8 degrees. The incidence of radiographic junctional degeneration was 24%, although no patients required surgery for symptomatic junctional degeneration. Mean ROM of prostheses below a degenerated junctional disc was 1.6 degrees compared with 4.7 degrees below a normal junctional disc (P < 0.035). Females were 3.5 times more likely to have ROM of <2 degrees. This is the longest published follow-up study of a lumbar disc replacement. The data show that ROM is preserved at long-term follow-up in the majority of patients. Global and segmental sagittal alignment improve after surgery. Furthermore, there is an association between ROM of disc prostheses and the development of junctional degeneration.     

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。     

颈椎前路Hybrid术在治疗颈椎退行性疾病中对活动度和曲度的影响

目的:观察颈椎前路Hybrid术后6个月影像学上颈椎曲度和活动度的变化.方法:回顾性分析2017年1月至2018年7月接受颈椎前路Hybrid术的颈椎退行性疾病患者,符合纳入标准并获得术前和术后6个月影像学资料者29例.男11例,女18例,年龄34～76(55.86±10.69)岁,手术时间2～4(3.03±0.51)...     

山羊颈椎次全切除减压非融合后生物力学特性

目的 探讨山羊颈椎次全切除减压非融合后生物力学特性.方法 选取成年雄性山羊6只造模(模型组),术前行颈椎X线检查,排除骨性结构异常,并测量节段性Cobb角(SCA)和颈椎Cobb角(CCA)于C4行颈椎次全切除术,并植入可动人工颈椎(ACV).术后行颈椎正侧位X线检查,再次测量SCA和CCA.术后6个月处死山羊,并以6...     

Long-term kinematic analysis of cervical spine after single-level implantation of Bryan cervical disc prosthesis

Background contextCervical arthroplasty theoretically reduces the risk of adjacent level disc degeneration and segmental instability that may be seen after a cervical fusion. An essential argument in confirming the utility of cervical arthroplasty is long-term confirmation that cervical disc replacements can maintain physiological kinematics at the index and adjacent levels.PurposeThe purpose of this in vivo prospective study was to characterize the long-term segmental kinematic outcomes after cervical arthroplasty.Study design/settingProspective cohort study.Patient sampleTwenty patients with a 5-year clinical follow-up who underwent anterior cervical discectomy with insertion of the Bryan cervical disc.Outcome measuresPhysiological measures (kinematic analysis of lateral neutral, flexion, and extension radiographic imaging).MethodsTwenty consecutive patients with degenerative disc disease were followed with regular radiographic imaging after implantation of the Bryan cervical disc prosthesis. Lateral neutral, flexion, and extension radiographs (n=240) were analyzed using Quantitative Motion Analysis software (Medical Metrics, Inc., Houston, TX, USA) to measure the biomechanical profile at the index level and adjacent levels up to 5 years after surgery. Parameters collected included range of motion (ROM), functional spinal unit (FSU) angle, anterior and posterior disc heights, sagittal translation, and center of rotation (COR).ResultsBiomechanics of the implanted artificial cervical disc was maintained up to 5 years with no significant changes in ROM, FSU angle, disc height, sagittal translation, and COR values when compared with early postoperative performance. Artificial discs were able to adequately restore and maintain preoperative kinematics. Early differences seen in disc height and FSU angle did not change during the duration of follow-up. No significant kyphotic changes or decrease in ROM were seen at the adjacent spinal levels.ConclusionsThe Bryan cervical disc prosthesis provides for a durable solution for functional spinal motion at the operated level and maintained the preoperative kinematics at adjacent levels at the 5-year follow-up.     

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.     

The factors that influence the postoperative segmental range of motion after cervical artificial disc replacement

Background contextAdvantages of cervical artificial disc replacement (ADR) are to preserve segmental range of motion (ROM) and avoid adjacent segmental disease. To achieve successful outcome after cervical ADR, ROM maintenance is important, but few authors have investigated the factors that influence the postoperative segmental ROM.PurposeTo evaluate the factors that influence the postoperative segmental ROM after cervical ADR.Study design/settingA retrospective clinical study.Patient sampleForty-one consecutive cervical ADR cases were analyzed.Outcome measuresDisc height, segmental and overall ROM, and clinical parameters checked with Neck Disability Index (NDI) and visual analog scale (VAS) in neck and arm pain were assessed.MethodsThere were 21 men and 20 women with a mean age of 45 years (range, 27–61 years). All cases were followed up for more than 2 years (range, 24–54 months; average, 31 months). Angles of the inserted implant on the immediate postoperative lateral radiographs, segmental and overall ROM (full flexion angle?full extension angle), disc height increment (immediate postoperative disc height?preoperative disc height), and adjacent segment changes at cephalad and caudal disc space were measured. Correlations between the factors and segmental ROM at last follow-up were analyzed.ResultsMean preoperative NDI was improved from 61.0 preoperatively to 11.5 at last follow-up, and mean VAS in the neck pain decreased from 56.8 preoperatively to 11.8 postoperatively and arm pain decreased from 68.1 to 18.0. The mean preoperative segmental ROM changed from 7.4±3.2° preoperatively to 10.4±5.9° at last follow-up, and mean preoperative disc height increased from 6.4±1.0 (4.1–8.4) mm preoperatively to 7.9±1.0 (6.3–9.9) mm postoperatively. The segmental ROM at last follow-up was not significantly correlated with preoperative segmental and overall ROM, angle of inserted implant, VAS, or age (p>.05). However, the segmental ROM at last follow-up was significantly correlated with the disc height increment (p=.046, r=0.374) and preoperative NDI (p=.026, r=0.412). The patient group with the postoperative segmental ROM greater than 10° had a significantly lower mean preoperative disc height than the group with the segmental ROM less than 10° (p=.050).ConclusionsAt a minimum of 2 years after cervical ADR, clinical outcomes were satisfactory in terms of function and pain scores. Within our results, the segmental ROM was not affected by preoperative ROM but postoperative disc height increment positively and preoperative disc height negatively.