寰枢椎脱位行寰枢椎后路融合手术后的下颈椎曲度变化情况及其预测因素

目的 探讨寰枢椎脱位(atlantoaxial dislocation,AAD)患者行寰枢椎后路融合手术后的下颈椎曲度变化情况,并分析其潜在的预测因素.方法 纳入本院自2012年1月～2019年3月采用寰枢椎后路固定融合手术治疗的31例AAD患者作为研究对象,统计所有患者的性别、年龄和手术前后的下颈椎曲度(C2-C7角)、其他颈椎矢状面参数[包括:枕颈角(C0-C2角),C1-C2角,颈椎前凸角(C0-C7角),颈椎矢状面轴向垂直距离(C2-C7 sagittal vertical axis,C2-C7 SVA),T1倾斜角(T1 slope,T1 S),颈部倾斜角(neck tilt,NT)和胸廓入口角(thoracic inlet angle,TIA)]变化情况.随访观察术后C2-C7角变化情况,若有所减小,则视为下颈椎曲度减小(A组);若有所增加或不变者,纳入B组.对两组患者性别、年龄等人口学资料,以及手术前后的相关颈椎矢状位参数进行单因素分析;并以二分类Logistic回归分析对相关因素进行多因素分析.结果 31例AAD患者均顺利完成后路寰枢椎固定融合术,术后获访9～15个月、平均(12.1±2.8)个月,术后出现下颈椎曲度减小者9(29.03％)例.单因素分析显示,术前C2-C7角、术后C1-C2角存在统计学意义(P<0.05).多因素Logistic回归分析显示,术前C2-C7角≥20°(OR=8.276,P=0.001)和术后C1-C2角≥20°(OR=6.754,P=0.013),均是AAD患者术后下颈椎曲度减小的独立预测因素.结论 下颈椎曲度减小在AAD患者行寰枢椎后路固定融合手术后并不少见,术前C2-C7角≥20°、术后C1-C2角≥20°可增加其发生风险.     

后路寰枢椎融合术后颈椎矢状面参数变化及相关因素分析

目的:测量后路寰枢椎融合手术对颈椎矢状面参数的变化,并对其相关影响因素进行评估。方法:回顾性研究2015年1月～2017年12月收治的寰枢椎脱位病例18例,男8例,女10例,年龄25～72岁,平均49.6±13.7岁。所有寰枢椎脱位患者均行单纯后路复位C1～C2固定融合术,随访时间为5～17个月,平均7.4±3.7个月。测量患者术前和末次随访时的枕颈角(C0～C2角)、下颈椎前凸角(C2～C7角)、颈椎前凸角(C0～C7角)、颈椎矢状面轴向垂直距离(C2-C7 sagittal vertical axis,C2-C7 SVA)、C1～C2角、T1倾斜角(T1 slope,T1S)、颈部倾斜角(neck tilt,NT)和胸廓入口角(thoracic inlet angle,TIA)等颈椎矢状面参数。在末次随访时,术后C2～C7角比术前减小的病例归为下颈椎前凸曲度减小组(5例),而术后C2～C7角比术前增加或不变的病例纳入下颈椎前凸曲度增加组(13例)。采用卡方检验做下颈椎前凸曲度减小与性别、年龄(以60岁为界限)、术前T1S(以25°为界限)、术前C2-C7 SVA(以15mm为界限)、术前TIA(以70°为界限)、术前C2-C7角(以20°为界限)、术前C0-C2角(以20°为界限)、术前C0-C7角(以45°为界限)和术后C1-C2角(以20°为界限)等临床因素相关性的单因素分析。采用Logistic回归对术后下颈椎前凸曲度减小的相关因素进行多因素分析。结果:所有患者术前和末次随访时的C0～C2角分别为21.6°±16.4°和28.3°±8.6°、C2～C7角分别为15.3°±12.9°和16.4°±11.1°、C0～C7角分别为36.8°±19.7°和44.9°±13.2°、C1～C2角分别为12.4°±17.6°和17.5°±7.3°、C2～C7 SVA分别为13.4±14.7mm和15.1±11.7mm、T1S分别为22.8°±8.2°和23.5°±7.3°、NT分别为50.8°±9.5°和51.9°±8.9°、TIA分别为73.6°±11.1°和75.4°±10.0°,以上这些颈椎矢状面参数在术前与末次随访的比较均无显著性差异(P0.05)。对两组患者术前和末次随访的颈椎矢状面参数进行比较,前凸减小组的术前C2～C7角明显大于前凸增加组(27.6°±10.5°vs 10.5°±10.5°,P0.05),余参数比较无统计学差异。单因素卡方分析显示术后下颈椎前凸曲度减小与术前C2～C7角≥20°有关(χ~2=4.923,P=0.026),多因素Logistic回归分析显示术前C2～C7角≥20°并不是独立危险因素(OR=0.147,P=0.225)。结论:后路寰枢椎融合术后有可能发生下颈椎前凸曲度减小,而术前C2-C7角≥20°是术后下颈椎前凸曲度减小的危险因素。     

双侧经寰枢关节螺钉寰椎椎板钩固定植骨融合治疗可复性寰枢椎脱位的中长期随访报告

目的:评估双侧经寰枢关节螺钉寰椎椎板钩固定植骨融合治疗可复性寰枢椎脱位的中长期疗效。方法:回顾性分析85例在我院接受双侧经寰枢关节螺钉寰椎椎板钩固定植骨融合术的可复性寰枢椎脱位患者的临床资料,其中男21例,女64例;年龄25~65岁(44±9.4岁)。寰椎爆裂性骨折19例,C1、2旋转脱位畸形16例,齿状突骨折26例,齿状突游离15例,寰椎类风湿性关节炎致寰枢椎脱位9例。通过Ranawat分级、颈椎功能障碍指数(NDI)以及颈部/枕骨下疼痛视觉模拟量表(visual analogue scale,VAS)评分评估患者的临床疗效;在术前和末次随访时的颈椎正侧位X线片、MRI、CT三维重建等资料中,提取以下影像学数据:寰齿前间距(atlanto-dental interval,ADI)、有效椎管容积(space available for cord,SAC)、C1-2角、C2-7角,并观察植骨融合情况及颈椎稳定性。结果:所有患者均完成5年以上的随访。末次随访时24例术前存在脊髓压迫症状患者的Ranawat分级有所改善;95%的患者颈部疼痛得到缓解,VAS评分由术前7.56±1.03分下降至2.53±0.53分(P0.05);NDI由术前34.76±5.45分降至13.13±1.21分(P0.05)。ADI由术前6.5±1.0mm降至2.4±0.9mm(P0.05);SAC由术前13.37±2.11mm增大至19.93±2.20mm(P0.05)。手术前C1-2角为21.9°±1.2°,末次随访时为26.6°±6.9°;手术前C2-7角为19.8°±9.2°,末次随访时为15.5°±5.9°。术后6个月,81例(95.3%)患者获得良好的植骨融合,4例患者出现植骨延迟愈合。结论:双侧经寰枢关节螺钉寰椎椎板钩固定植骨融合治疗可复性寰枢椎脱位的长期疗效优良,是一种安全、可靠的后路寰枢椎固定融合技术。     

椎弓根螺钉内固定术治疗儿童寰枢椎脱位的颈椎活动功能观察

目的探讨寰枢椎椎弓根螺钉内固定手术治疗儿童寰枢椎脱位的颈椎活动功能康复和临床疗效。方法2005年9月-2013年3月对21例儿童寰枢椎脱位患者采用寰枢椎椎弓根螺钉内固定术治疗,男12例,女9例;年龄5-14岁,平均8.9岁。术前颈椎活动度（range of motion,ROM）为前屈26.32°±5.43°、后伸49.58°±4.38°、左旋42.68°±4.46°、右旋41.55°±5.33°、左侧屈28.31°±5.47°、右侧屈27.82°±5.85°。术中采用＂寰椎椎弓根显露置钉法＂置钉。随访患者神经功能改善和颈椎活动功能情况。结果 21例均行双侧寰枢椎椎弓根螺钉内固定并置钉成功。随访12-92个月,平均32.5个月,术后3-6个月寰枢椎均骨性融合。末次随访颈椎ROM前屈48.12°±4.92°、后伸57.91°±5.15°、左旋58.37°±5.36°、右旋57.51°±5.74°、左侧屈36.57°±4.39°、右侧屈37.44°±4.53°。结论椎弓根螺钉内固定技术治疗儿童寰枢椎脱位,能提供可靠的寰枢椎短节段固定融合和稳定性重建,是一种使颈椎活动功能得到有效康复的治疗方法。     

寰枢关节不稳或脱位患者上颈椎曲度改变对下颈椎的影响

目的:探讨寰枢关节不稳或脱位患者上颈椎的曲度变化对下颈椎力线和退变的影响.方法:在148例寰枢关节不稳定或脱位患者的颈椎中立位X线片上测量CO-1、C1-2、CO-2及C2-7角度,评估颈椎间盘的退变程度.分析上、下颈椎曲度之间以及颈椎曲度与年龄、病程之间的相关性,观察不同年龄组上颈椎曲度对下颈椎椎间盘退行变的影响.结果:CO-1角度为-22.9°18.6°(n=88);CI-2角度为-31.7°～39.1°(n=88);CO-2角度为-35.2°～44.8°(n=148);C2-7角度为-17.4°77.8.(n=148).C1-2和C2-7角度之间、C0-2与C2-7角度间、C0-1与C1-2角度之间存在显著负相关性.上、下颈椎曲度与病程、年龄无相关性.30～39岁组、40～49岁组及50～59岁组C5/6椎间盘退变、60岁以上组C2/3椎间盘退变与上颈椎角度(C0-2角度)之间存在显著负相关.结论:上、下颈椎曲度间存在密切关系,寰椎前脱位可导致下颈椎出现代偿性过度前凸,即鹅颈畸形,鹅颈畸形可能加速下颈椎的退变进程.     

后路寰枢椎融合术后下颈椎前凸曲度降低的影响因素研究

目的 探讨后路寰枢椎融合术后下颈椎前凸曲度降低的影响因素。方法 选择2016年4月～2018年4月本院收治的84例寰枢椎脱位患者为研究对象，均采用后路寰枢椎融合术治疗，随访2年，根据术前、术后的下颈椎前凸角变化设为降低组以及不变或增加组，比较两组患者年龄、性别、术前枕颈角、下颈椎前凸角、颈椎矢状面轴向垂直距离(C_2-7 sagittal vertical axis, C_2-7SVA)、T₁倾斜角(T₁ slope, T₁S)、术后C_1-2角等临床资料，采用Logistic回归分析法调查术后下颈椎前凸曲度降低的独立影响因素。结果 术后下颈椎前凸曲度降低者26例，不变或增加者58例。两组患者年龄、术前枕颈角、下颈椎前凸角、C_2-7SVA、术后C_1-2角差异有统计学意义(P<0.05);两组患者性别、术前T₁S差异无统计学意义(P>0.05)。Logistic回归分析显示，年龄≥60岁...     

后路寰枢椎椎弓根钉内固定及融合术治疗上颈椎不稳11例

目的总结采用寰枢椎椎弓根钉内固定及植骨融合术治疗上颈椎不稳的疗效。方法对11例上颈椎不稳患者术前常规行颅骨牵引复位。术中寰枢椎椎弓根的进钉点选择在寰椎后结节中点旁开18～20 mm、后弓上缘下4 mm交点处,矢状面上螺钉向头侧倾斜约5°,与矢状面夹角10°;枢椎进钉点为枢椎关节突根部中点,钉道与矢状面夹角为20～25°,与横断面夹角30～35°。椎弓根钉直径3.5 mm,寰椎、枢椎椎弓根钉长22～28 mm。结果随访5～34个月,11例均植骨融合,内固定无松动断裂。术后JOA评分:优7例,良2例,可2例。结论采用寰枢椎多轴椎弓根钉棒系统内固定及植骨融合术治疗上颈椎不稳,具有固定牢固、固定节段短和三维固定的优点。     

强直性脊柱炎合并寰枢椎脱位的影像学特点及手术疗效

目的 :分析强直性脊柱炎(ankylosing spondylitis,AS)合并寰枢椎脱位(atlantoaxial subluxation,AAS)的影像学特点,评估手术治疗的临床疗效。方法:回顾性分析2001年11月～2019年2月于我院接受颈枕融合或上颈椎融合术治疗的AS合并AAS的患者资料8例,均为男性,年龄15～59岁,平均39.9±16.2岁。术前颈椎侧位X线片示所有患者均存在寰枢椎脱位,寰齿前间隙(anterior atlantodental interval,AADI)平均为10.4±7.0mm(2～17mm);其中5例为前脱位,AADI平均为15.2±2.7mm(11～17mm),另3例为后脱位合并齿状突骨折。3例患者术前伴不全瘫(Frankel D级2例,Frankel C级1例)。在术前、术后即刻及末次随访的颈椎侧位X线片上测量C0-C2角、C1-C2角、C2-C7角、C2-C7矢状面偏移(sagittal vertical axis,SVA)和AADI。采用Frankel分级评估术前及术后出院前的神经功能状态。应用配对样本t检验比较术前、术后影像学参数。记录手术并发症情况。结果:7例获得随访,随访时间3～96个月,平均37.9±38.5个月。C0-C2角术前为18.9°±16.8°,术后改善至22.6°±15.4°,末次随访时为20.4°±11.4°;C1-C2角术前为19.6°±18.7°,术后改善至28.5°±10.1°,末次随访时为24.6°±8.1°;术前C2-C7角平均为-6.4°±25.2°,术后改善至6.6°±19.7°,末次随访时为9.0°±18.8°;C2-C7 SVA术前为46.0±36.5mm,术后改善至39.4±26.4mm,末次随访时为39.6±18.9mm,C0-C2角、C1-C2角、C2-C7角及C2-C7 SVA术前、术后的差异均无统计学意义(P0.05)。AADI术前为10.4±7.0mm,术后显著改善至6.4±4.1mm(P0.05),差异具有统计学意义,末次随访时为6.9±4.6mm。3例术前不全性瘫痪者,术后神经功能均有一定程度的恢复,其中2例术前Frankel D级者恢复至E级;另1例由术前Frankel C级改善至D级。所有患者均未发生神经并发症及浅表、深部感染,且无断钉、断棒、螺钉松动等内固定并发症发生。结论:AS合并AAS在影像学上多表现为前脱位,手术治疗AS合并AAS可取得良好的疗效。术前伴神经损害者需行后路C1后弓切除减压。后路颈椎/颈胸段截骨矫形适用于明显颈椎/颈胸段后凸畸形患者。     

后路内固定融合手术治疗类风湿性寰枢椎不稳

目的 :评估后路内固定融合节段对治疗类风湿性寰枢椎不稳临床疗效的影响。方法 :2008年1月~2015年3月收治类风湿性寰枢椎不稳患者24例,其中女15例,男9例;年龄37~64岁(50.8±4.3岁)。21例患者入院前已经诊断为类风湿性关节炎(RA),病程2~30年(15.6±7.8年);3例患者本次入院确诊为RA并且伴有寰枢椎不稳。侧位X线片示寰枢椎脱位(AAS)13例;寰枢椎垂直脱位(VS)5例;AAS+VS 2例;AAS+下颈椎半脱位(SAS)1例;后路钢丝固定术后3年钢丝断裂合并下颈椎SAS 1例;寰枢关节破坏无脱位表现2例。均行后路固定融合手术,13例AAS患者10例行后路寰枢椎(C1-2)融合内固定术,2例因C2椎弓根细小行C1-C3固定融合,1例因寰椎后弓细小及骨质疏松行枕颈融合术(O-C2);7例VS/AAS+VS患者及2例严重枕颈部疼痛的患者行枕颈融合术,O-C2融合3例,O-C3融合6例,其中1例行寰椎后弓切除减压;2例合并SAS的患者行枕颈椎/胸椎(O-C7 1例,O-T1 1例)固定融合,包括1例翻修手术。比较患者术前、术后及末次随访时的Ranawat神经功能分级、VAS和JOA评分。结果 :24例患者手术均顺利完成,无术中并发症;术后伤口浅表感染2例,经换药和使用敏感抗菌素治愈。24例患者均获得随访,随访时间12~45个月(24.1±10.3个月)。VAS评分由术前的6.6±1.2分下降到术后的2.6±0.9分,末次随访时1.8±0.7分(P0.05)。JOA评分由术前的平均11.5±1.9分增加到术后的平均13.6±2.0分,末次随访时14.5±1.1分(P0.05)。Ranawat神经损伤分级:3例术前Ⅰ级无恢复;5例Ⅱ级者4例恢复至Ⅰ级,1例无恢复;15例Ⅲa级恢复至Ⅰ级13例,Ⅱ级2例;1例Ⅲb级恢复至Ⅲa级。术后3个月植骨融合率为29%(7例),术后6个月为79%(19例),术后12个月为100%(24例)。术后继发SAS 3例,脱位部位:C3/4 2例,C4/5 1例。结论:类风湿性寰枢椎不稳患者行后路内固定融合手术治疗效果满意,应根据病变累及范围、脱位类型、骨密度和钉道情况选择固定融合范围。     

线缆内固定融合术治疗创伤性寰枢椎不稳的中远期疗效

目的 探讨线缆内固定融合术治疗创伤性寰枢椎不稳的中远期疗效.方法 2004年7月—2015年7月,22例创伤性寰枢椎不稳患者在中国人民解放军海军第九七一医院和海军军医大学长征医院接受后路线缆内固定融合术治疗及随访,其中12例采用Gallie术式,10例采用Brooks术式.记录患者术前、术后及末次随访时头颈椎旋转角、下颈椎后凸角、日本骨科学会(JOA)评分、疼痛视觉模拟量表(VAS)评分、颈椎功能障碍指数(NDI),评价疗效及预后.结果 22例患者随访5～16(7.5±2.3)年,20例患者获得了一期骨性融合;Gallie术式、Brooks术式各1例随访2年未融合,改行Magerl螺钉并Brooks融合术,末次随访获得骨性融合.所有患者术后3个月及末次随访JOA评分、VAS评分、NDI与术前相比明显改善,差异均有统计学意义(P<0.05),末次随访与术后3个月比较差异均无统计学意义(P>0.05).末次随访时下颈椎后凸角与术前及术后3个月相比,差异均有统计学意义(P<0.05).末次随访时头颈椎旋转角与术后3个月相比差异有统计学意义(P<0.05).末次随访时患者头颈部旋转功能平均丢失13.5％,下位颈椎不同程度后凸畸形发生率为63.6％(14/22).结论 线缆内固定融合术治疗创伤性寰枢椎不稳中远期疗效满意;但融合术后头颈部旋转功能少量丢失,远期下位颈椎后凸畸形发生率较高.     

Sagittal alignment of the subaxial cervical spine after C1-C2 transarticular screw fixation in rheumatoid arthritis

Several articles reported the association between the development of subaxial kyphosis and the hyperlordotic fixation of C1-C2. However, their patients were heterogeneous in both primary disease and operative procedure. Transarticular screw fixation has become a popular procedure for C1-C2 arthrodesis instead of wiring techniques in which C1-C2 is difficult to fix in the intended alignment. Furthermore, in rheumatoid arthritis (RA) patients, subaxial lesions play an important role in potential subaxial alignment changes. The subaxial influences after C1-C2 transarticular screw fixation in patients with RA are unclear. To investigate the radiographic features of the subaxial cervical spine after C1-C2 transarticular screw fixation for RA, we reviewed 28 cases of C1-C2 transarticular screw fixation for rheumatoid atlanto-axial subluxation. The sagittal alignment of C1-C2 and the subaxial cervical spine was measured and the factors that affect subaxial alignment were investigated. Subaxial alignment became less lordotic in the postoperative course. The C1-C2 fixation angle and subaxial alignment showed a negative linear correlation. However, no significant correlation was found between changes in the C1-C2 angle and changes in the subaxial alignment. Four patients had a postoperative kyphotic subaxial deformity. Neurologic deterioration recurred in 4 patients, because of the postoperative development of subaxial subluxation. Common radiographic changes included an increase in C1-C2 lordosis, constant inclination of C1, an anterior shift of C2, and a decrease in C2-C7 lordosis. Many factors, not only C1-C2 angle, are associated with subaxial sagittal alignment change after C1-C2 transarticular screw fixation.     

选择性融合联合单开门椎管扩大椎板成形术治疗局部不稳的颈椎后纵韧带骨化症的疗效

目的:比较三种颈椎后路术式治疗存在局部不稳的颈椎后纵韧带骨化症(ossification of the posterior longitudinal ligament,OPLL)患者的临床疗效,探讨选择性融合联合单开门椎管扩大椎板成形术的临床应用价值。方法:回顾分析我院2014年6月~2017年6月收治的存在局部不稳的颈椎OPLL患者107例,其中男性61例,女性46例;年龄68.1±10.2岁(33~84岁),随访时间2.1±1.3年(0.5~3.5年)。所有患者证实存在OPLL及颈椎局部不稳,且存在颈脊髓压迫相关症状体征,其中38例行单纯颈后路单开门椎管扩大椎板成形术(A组),35例行选择性融合联合单开门椎管扩大椎板成形术(B组),34例行传统颈后路椎板切除固定术式(C组)。分别于术前、术后2d及末次随访时采用日本矫形外科学会(Japanese Orthopaedic Association,JOA)评分并计算Hirabayashi改善率,对患者的神经功能情况进行评估;拍摄颈椎正侧位及过屈过伸位X线片测量颈椎的曲度(C2-7 Cobb角)、颈椎整体活动度(C2-7 range of motion,C2-7 ROM)和颈椎不稳节段的活动度,统计内固定相关并发症。通过颈椎MRI评估患者颈髓高信号的情况并计算高信号强度比值(high signal intensity ratio,HSIR)。比较三组患者颈椎整体活动度和不稳节段的活动度,比较存在颈髓高信号患者的术前、术后HSIR及三组之间的差异。结果:三组患者均取得了满意的神经功能改善,末次随访时JOA评分分别为14.93±3.18分、15.22±2.79分和14.72±3.02分,Hirabayashi改善率分别为(66.35±13.48)%、(70.06±14.14)%和(64.14±18.05)%。三组患者术前颈椎曲度分别为7.43°±3.69°、7.66°±2.99°、6.96°±4.38°,组间比较无统计学差异(F=13.19,P=0.071),末次随访时颈椎曲度与术前相比基本一致(5.58°±4.26°、5.73°±3.81°、5.49°±4.33°),随访期间未发现颈椎曲度明显改变、后凸等情况。随访期间未出现内固定相关并发症。末次随访时A、B两组患者颈椎整体活动度(C2-7 ROM)无统计学差异(17.63°±8.31°和18.72°±9.52°,P=0.089),C组患者末次随访颈椎整体活动度明显差于A、B两组患者(3.90°±7.74°vs 17.6°±8.3°,P=0.012;3.90°±7.74°和18.72°±9.52°,P=0.003);B组、C组患者术后颈椎不稳节段活动度明显降低,末次随访时已完全融合。共有71例(71.03%)患者出现颈椎MRI T2加权高信号表现,存在高信号的节段与存在不稳的节段一致。三组患者HSIR值末次随访时均较术前明显降低(1.33±0.18 vs 1.68±0.11,1.12±0.12 vs 1.71±0.14和1.20±0.33 vs 1.65±0.18,P=0.001),但与A组患者相比,B组和C组患者的降低程度均较显著,差异存在统计学意义(P<0.05)。结论:选择性融合联合单开门椎管扩大椎板成形术是治疗存在局部不稳的颈椎OPLL患者的有效方法,可以在广泛减压颈脊髓压迫的同时增加颈椎的节段稳定性,同时保留颈椎一定的活动度、减少术后轴性症状发生。     

Laminar screw fixation in the subaxial cervical spine: A report on three cases

Although laminar screw fixation is often used at the C2 and C7 levels, only few previous case reports have presented the use of laminar screws at the C3-C6 levels. Here, we report a novel fixation method involving the use of practical laminar screws in the subaxial spine. We used laminar screws in the subaxial cervical spine in two cases to prevent vertebral artery injury and in one case to minimize exposure of the lamina. This laminar screw technique was successful in all three cases with adequate spinal rigidity, which was achieved without complications. The use of laminar screws in the subaxial cervical spine is a useful option for posterior fusion of the cervical spine.     

高位颈前入路复位固定治疗Ⅱ型及ⅡA型Hangman骨折

目的：评价高位颈前入路复位固定治疗Ⅱ型及ⅡA型Hangman骨折的临床疗效。方法对2005年1月至2013年5月中山大学第一附属医院收治的21例Ⅱ型及ⅡA型Hangman骨折患者行高位颈前入路C2～C3椎间盘切除、复位及融合固定手术。记录手术时间、术中出血量,测量术后1周及末次随访时C2～C3前凸角;观察复位及并发症发生情况。结果手术时间50～90 min（平均75 min）;术中出血量20～100 mL（平均55 mL）。术中无神经血管损伤并发症,所有患者成功获得固定。19例C2前脱位患者中,16例获得完全复位;3例基本复位。术后1周C2～C3平均前凸角为（3.1±0.8）°,优于术前的（-9±2.5）°（P＜0.05）;19例患者获得平均3年3个月（6个月至7年）的有效随访,末次随访时C2～C3平均前凸角为（2.6±0.5）°,未有明显丢失。所有患者获得椎间融合,未出现内固定松动、脱出、断裂等并发症。结论高位颈前入路C2～C3椎间盘切除、复位及融合固定治疗Ⅱ型及ⅡA型Hangman骨折,复位理想,内固定牢靠,能有效纠正和维持患者的颈椎前凸,融合率高,疗效满意。     

Sagittal alignment as a predictor of clinical adjacent segment pathology requiring surgery after anterior cervical arthrodesis

Background contextPostoperative malalignment of the cervical spine may alter cervical spine mechanics and put patients at risk for clinical adjacent segment pathology requiring surgery.PurposeTo investigate whether a relationship exists between cervical spine sagittal alignment and clinical adjacent segment pathology requiring surgery (CASP-S) following anterior cervical fusion (ACF).Study designRetrospective matched study.Patient sampleA total of 122 patients undergoing ACF between 1996 and 2008 were identified, with a minimum of 2 years of follow-up.Outcome measuresRadiographs were reviewed to measure the sagittal alignment using C2 and C7 sagittal plumb lines, distance from the fusion mass plumb line to the C2 and C7 plumb lines, the alignment of the fusion mass, caudally adjacent disc angle, the sagittal slope angle of the superior end plate of the vertebra caudally adjacent to the fusion mass, T1 sagittal angle, overall cervical sagittal alignment, and curve patterns by Katsuura classification.MethodsA total of 122 patients undergoing ACF between 1996 and 2008 were identified, with a minimum of 1 year of follow-up. Patients were divided into groups according to the development of CASP (control/CASP-S) and by number/location of levels fused. Radiographs were reviewed to measure the sagittal alignment using C2 and C7 sagittal plumb lines, distance from the fusion mass plumb line to the C2 and C7 plumb lines, the alignment of the fusion mass, caudally adjacent disc angle, the sagittal slope angle of the superior end plate of the vertebra caudally adjacent to the fusion mass, T1 sagittal angle, overall cervical sagittal alignment, and curve patterns by Katsuura classification. Appropriate statistical tests were performed to calculate relationships between the variables and the development of CASP-S. No funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this article.ResultsThe groups were similar with regard to demographic and surgical variables. Lordosis was preserved in 82% (50/61) of the control group but in only 66% (40/61) of the CASP-S group (p=.033). More patients with a straight curve pattern developed CASP-S. The distance from the C2 to the C7 plumb line and T1 sagittal slope angle were lower in the CASP-S group with C5–C6 fusions compared with the control group. Also, the distance from C5–C6 fusion mass to C7 plumb line and C7 sagittal slope angle were lower in the CASP-S group with C5–C6 fusions.ConclusionsOur results suggest that malalignment of the cervical spine following an ACF at C5–C6 has an effect on the development of clinical adjacent segment pathology requiring surgery.     

颈椎后纵韧带骨化症病变范围涉及第二颈椎时后路减压与伸肌重建策略

目的 探讨颈椎后纵韧带骨化症(OPLL)病变范围涉及第二颈椎时行后路减压和伸肌重建的方法.方法 2002至2006年治疗OPLL病变范围涉及C2者10例,均行保留颈后方韧带复合体、重建颈伸肌群附着点、单开门颈椎板成形术,椎板成形减压范围C2～C7.测量手术前后CT片上C2有效椎管矢状径,计算减压程度;测量手术前后X线片上C2～C7角,对比生理曲度维持情况;记录手术前后和随访时JOA评分.结果 平均随访14个月,C2有效椎管矢状径术前平均5.6 mm(4.0～8.8 mm)、术后平均13.4 mm(10.0～18.2mm)(与术前相比P<0.01);中立位C2～C7角术前6.5°(-2°～12°)、术后7.4°(3°～14°)、末次随访7.0°(2°～15°)(与术前相比P>0.05);JOA评分术前6～12分(平均9.6分)、术后8～14分(平均10.9分)、末次随访10～17分(平均13.2分)(与术前相比P<0.05).结论 保留颈后方韧带复合体重建颈伸肌群附着点单开门颈椎板成形术,对病变范围涉及第二颈椎的OPLL是适宜的手术方法,可以达到减压彻底、维持颈椎生理曲度的目的 .     

Biomechanical comparison of adjacent segmental motion after ventral cervical fixation with varying angles of lordosis.

BACKGROUND CONTEXT: Complications, such as graft subsidence and adjacent segment degeneration, are not uncommon after ventral cervical fusion. It has been theorized, but not proven, that sagittal alignment may affect this process. It is therefore hypothesized that increasing lordosis during anterior cervical fusion decreases adjacent segment motion (ASM) and thus decreases the rate of adjacent disc degeneration. A study was designed to test the first portion of this hypothesis; ie, that increasing lordosis during anterior cervical fusion decreases ASM. PURPOSE: To determine the effect on the adjacent segment motion (ASM) after ventral cervical spine fusion obtained by varying the angle of lordosis using interbody spacers with different heights (small: 6-mm interbody spacer; large: 9-mm interbody spacer). STUDY DESIGN: A biomechanical study comparing the segmental motion at adjacent disc levels after cervical fusion with varying angles of lordosis. Sample and outcome measures: six human cadaveric spines C2-C7, range of motion (ROM). METHODS: Six fresh human cadaveric cervical spines (C2-C7) were embedded at C2 and C7 and biomechanically tested to 0.7 Nm flexion and 0.5 Nm extension. Lordosis was measured at C4-C5 from radiographs; range of motion (ROM) at C3-C4, C4-C5, and C5-C6 was measured using markers during flexion and extension in the intact state, after ventral cervical fixation at C4-C5 with a small (6-mm) and with a large (9-mm) interbody spacer. A repeated measures analysis of variance was used to compare lordosis and the ROM for the different states. RESULTS: Six cervical spines with a mean age of 55.3+/-1.6 years were studied. The mean sagittal angles of the specimens measured at C4-C5 using the Cobb angle method were -6.4+/-1.3 degrees intact, -8.8+/-1.4 degrees with small interbody spacer (intact vs. small spacer p=.02), and -12.4+/-0.9 degrees with large interbody spacer fixation (intact vs. large spacer p=.005). The lordotic angle of the specimens was lowest in the intact state, higher with the small spacer, and highest with the large spacer. The greatest ROM in the intact state testing was at C4-C5 (10.6+/-1.3 degrees), followed by at C5-C6 (7.2+/-1.5 degrees), and then at C3-C4 (7.1+/-0.9 degrees). After C4-C5 fusion, the ROM at C3-C4 and C5-C6 was significantly increased with the small spacer only. No significant change in ROM was observed with the large spacer. The greatest overall ROM (all three motion segments) was observed in the intact state (24.9+/-1.8 degrees), followed by the small spacer (21.4+/-2.0 degrees) and the large spacer (15.1+/-1.7 degrees). CONCLUSIONS: Under the conditions of this study, there is a significant increase in ASM with the achievement of a modest increase in lordosis (small spacer) that is not observed with a greater increase in lordosis (large spacer).     

下颈椎椎弓根螺钉内固定相关参数的解剖学和影像学测量

目的:测量成人下颈椎椎弓根相关径线,为临床应用下颈椎椎弓根螺钉内固定提供相关解剖参数.方法:成人干燥尸体颈椎C3～C7标本20具,分别用手工和CT测量椎弓根宽度、高度,从横断面CT图像上测量椎弓根的内部宽度、内部高度,从纵断面CT图像上测量椎弓根矢状角.随机在CT窒保存的100例成人患者的颈椎CT图像上测量椎弓根的宽度、自身长度和椎弓根通道全长、椎弓根内倾角.结果:下颈椎标本各节段椎弓根宽度、高度的手工测量值与CT测量值比较无统计学差异(P>0.05),椎弓根宽度小于高度;C3～C6节段CT测量椎弓根内部宽度平均为2.5～2.8mm,椎弓根内部高度平均为2.9～3.0mm,C7椎弓根的内部宽度和高度接近,约4.0mm;下颈椎标本CT测量椎弓根矢状角分别为C3 8.6°,C4 4.6°,C5-1.3.,C6-4.0°,C7-8.2°.100例成人下颈椎CT图像测量椎弓根宽度最小值为3.1mm(C3),最大值为9.3mm(C7),其中>3.5mm者为92.8%;椎弓根自身长度平均为19.1～20.5mm,椎弓根通道全长平均为33.2～35.0mm,椎弓根内倾角平均值C3～C5为43.2°～45.1°,C6为40.8°,C7为37.5°.结论:术前CT测量可为椎弓根准确置钉提供可靠的解剖参数,下颈椎椎弓根一般可接受直径3.5mm的螺钉同定.     

Subaxial subluxation after atlantoaxial transarticular screw fixation in rheumatoid patients

The most common cervical abnormality associated with rheumatoid arthritis (RA) is atlantoaxial subluxation, and atlantoaxial transarticular screw fixation has proved to be one of the most reliable, stable fixation techniques for treating atlantoaxial subluxation. Following C1–C2 fixation, however, subaxial subluxation reportedly can bring about neurological deterioration and require secondary operative interventions. Rheumatoid patients appear to have a higher risk, but there has been no systematic comparison between rheumatoid and non-rheumatoid patients. Contributing radiological factors to the subluxation have also not been evaluated. The objective of this study was to evaluate subaxial subluxation after atlantoaxial transarticular screw fixation in patients with and without RA and to find contributing factors. Forty-three patients who submitted to atlantoaxial transarticular screw fixation without any concomitant operation were followed up for more than 1 year. Subaxial subluxation and related radiological factors were evaluated by functional X-ray measurements. Statistical analyses showed that aggravations of subluxation of 2.5 mm or greater were more likely to occur in RA patients than in non-RA patients over an average of 4.2 years of follow-up, and postoperative subluxation occurred in the anterior direction in the upper cervical spine. X-ray evaluations revealed that such patients had a significantly smaller postoperative C2–C7 angle, and that the postoperative AA angle correlated negatively with this. Furthermore, anterior subluxation aggravation was significantly correlated with the perioperative atlantoaxial and C2–C7 angle changes, and these two changes were strongly correlated to each other. In conclusion, after atlantoaxial transarticular screw fixation, rheumatoid patients have a greater risk of developing subaxial subluxations. The increase of the atlantoaxial angel at the operation can lead to a decrease in the C2–C7 angle, followed by anterior subluxation of the upper cervical spine and possibly neurological deterioration.