对称性可调节式椎弓根钻孔导向器的研制及应用

目的：研制一种椎弓根钉钻孔导向器供术中使用，提高椎弓根螺钉置入的成功率及置入质量。方法：根据术前CT及X线片测定的水平面椎弓根钉置入角(TSA)、矢状而椎弓根钉置入角(SSA)及进钉点间距的数据，应用该钠孔导向器引导术中椎弓根螺钉钻孔操作。临床应用于21例胸腰椎骨折及腰椎滑脱患者，置入椎弓根钉84枚。结果：术后CT及X线片显示全部椎弓根钉置入位置准确，两侧椎弓根螺钉对称，具有相同或相近的SSA及TSA。结论：该钻孔导向器设计合理，使用方便，能提高椎弓根螺钉置入的准确性，可提高固定钉的安置质量。     

寰椎椎弓根进钉通道的数字解剖学研究

目的:探讨寰椎椎弓根进钉通道在矢状面角(SSA)为0°时不同水平面角(TSA)方向投影的变化规律。方法:将20例健康成年志愿者(男12例,女8例;年龄24~68岁,平均45岁)的寰椎CT连续断层扫描数据导入Mimics 10.01软件,三维重建寰椎数字解剖模型,将重建的结果以.stl格式保存,再将寰椎数字模型导入UG Imageware 12.0,建立寰椎椎弓根进钉通道数字化分析方法,确定三维参考平面,分析在SSA为0°时左右椎弓根TSA分别从0°～30°,均匀间隔5°,观察280个寰椎椎弓根进钉通道的长度和内切圆半径的变化规律。结果:280个寰椎椎弓根进钉通道的长度为20.54～33.21mm,其中11个通道长度小于最短椎弓根螺钉长度(22mm);TSA为0°进钉时左右通道长度均最大,左右侧比较无显著性差异(P0.05),5°～30°进钉时同一进钉角度左右侧比较有显著性差异(P0.05);同侧不同进钉角度比较无显著性差异(P0.05)。280个寰椎椎弓根螺钉通道的内切圆半径为1.38～2.51mm,其中有42个内切圆半径小于最小椎弓根螺钉半径(1.75mm);同一进钉角度右侧内切圆半径与左侧比较及同侧不同进钉角度比较均无显著性差异(P0.05)。结论:不同个体甚至同一个体的左右两侧椎弓根形态之间有较大差异。部分寰椎椎弓根进钉通道长度和内切圆半径小于椎弓根螺钉最小长度和最小半径,椎弓根进钉通道内切圆半径小于最小椎弓根螺钉半径时置钉会穿破椎弓根的皮质骨,不适合采用经寰椎椎弓根螺钉内固定技术。术前用数字化技术测量寰椎椎弓根进钉通道可以实现个体化置钉。     

微创经椎间孔腰椎椎间融合术中横突定位法置钉的影像学评价

目的 :探讨在微创经椎间孔腰椎椎间融合术(minimally invasive transforaminal lumbar interbody fusion,MISTLIF)中采用横突定位法置钉的可行性及术后影像学评价。方法 :回顾分析2014年1月~2014年12月行MISTLIF手术患者82例,根据置钉位置进行分组,其中治疗组(40例)按横突定位法置钉,其中男18例,女22例,平均年龄55.4±5.0岁(46~67岁)。对照组(42例)以"人字嵴"顶点法置钉,其中男20例,女22例,年龄56.2±5.5岁(47~70岁),术后平均随访24.0±3.5个月。分别记录两组出血量、手术时间,术后1年复查腰椎CT平扫+三维重建。按照Rao分级评估椎弓根螺钉穿出情况,CT轴位测量椎弓根螺钉水平角(transverse section angle,TSA),CT矢状位测量矢状角(sagittal section angle,SSA)。CT轴位评估椎弓根螺钉对头侧邻近节段关节突关节破坏(facet joint violation,FJV)情况。结果:两组年龄、性别、术前诊断构成比差异无统计学意义(P0.05),治疗组手术时间为95.0±10.5min,出血量为120.0±11.2ml,对照组手术时间为150.0±10.5min,出血量150.0±11.5ml,两组出血量差异无统计意义(P0.05),但两组手术时间差异具有统计学意义(P0.05)。Rao分级法评估椎弓根螺钉穿出情况两组椎弓根螺钉穿出率,差异无统计学意义(P0.05)。治疗组与对照组相比,SSA无统计学差异(P0.05),TSA具有统计学意义(P0.05)。两组FJV发生率差异具有统计学意义(P0.05)。结论:横突定位法,与"人字嵴"顶点法相比,均具有较高的置钉准确率,横突置钉法头侧邻近节段关节突关节破坏率低,且有利于通道下操作、缩短了置钉时间,但横突定位法置钉时进钉点偏外,术中需适当增大TSA。     

椎弓根轴线导向器的研制和应用研究

目的:通过解剖学标本研究和临床应用评价椎弓根轴线导向器引导椎弓根螺钉置入的准确性和安全性。方法:①解剖标本研究:全长脊柱标本6具(研究范围T1-S1),术前行螺旋CT扫描,测定椎弓根轴线入点间距、椎弓根轴线角度及其延长线在椎体内的长度。根据测量数据,应用椎弓根轴线导向器引导直径2.5mm克氏针沿椎弓根轴线置入。术后拔出克氏针,复查脊柱标本CT,分别测量记录数据:各椎克氏针钉道及延长线与椎体长轴线在水平面的交角(记作KTSA);矢状面上与棘突轴线的交角(记作KPSA);各椎实际入钉点间距(KDSP)。采用SPSS10.0统计软件分析所采集数据。②临床应用:应用于26例患者,男16例,女10例;年龄21～71岁,平均49.5岁。在导向器引导下共置入椎弓根螺钉112枚。术后通过CT或MRI验证置钉的准确性。结果:①解剖研究:克氏针的钉道与椎弓根轴线所成水平面角和矢状面角相接近(P>0.05);实际入钉点与设计入钉点重合(P>0.05)。②临床应用:术后所有病例共112枚椎弓根螺钉经CT或MR图像复查,按置入位置判断标准,优107枚(95.5%),良3枚(2.7%),差2枚(1.8%)。结论:椎弓根轴线导向器可以准确地引导顺椎弓根轴线钻孔,从而提高椎弓根钉置入的准确性和安全性。     

改良CT测量法用于椎弓根螺钉个体化植入的实验研究

[目的]探讨进钉点到棘突中心矢状面的垂直距离用于椎弓根螺钉个体化植入的可行性.[方法]于华中科技大学同济医学院解剖教研室收集成人脊柱标本30例,在CT横断面扫描图像上测量如下数据:椎弓根宽度a,进钉点到椎体前缘的距离b,进钉点到棘突中心矢状面的垂直距离c,椎弓根纵轴与椎体矢状轴的夹角A,在侧位片上测量椎弓根纵轴与操作台垂直线的夹角B,分为实验组和对照组,实验组采用CT图像上进钉点到棘突中心矢状面的垂直距离用于进钉点在水平方向上的定位,对照组采用Ebraheim法定位进钉点,置钉后行CT扫描,判断螺钉有无穿破椎弓根内侧或外侧壁及穿破程度,按照穿破程度进行分级:A=完全位于椎弓根内;B:穿破程度＜2 mm;C=穿破程度2～4 mm;D=穿破程度＞4 mm,并进行对比分析.[结果]实验组T3-10水平螺钉穿破率明显低于对照组,T1,T2,T 11,12:两组的穿破率相当.在T 3-18水平,螺钉的穿破程度(C,D级)明显高于其他节段,与椎弓根在这些节段横径变小有关;T 1-12,实验组中C,D级的发生率低于对照组.[结论]采用进钉点到棘突中心矢状面的垂直距离用于定位椎弓根螺钉进钉点,可以明显提高螺钉在水平方向上的植入准确性.尤其在L 3-10节段,而且特别适合由于解剖变异,外伤,肿瘤破坏等原因使关节突关节,横突等解剖标志发生改变时椎弓根螺钉的植入,亦可以在正常解剖情况下作为传统定位方法的有效补充.     

导向器结合钉道内壁探查法在下颈椎椎弓根螺钉置入中应用研究

目的:探讨导向器结合钉道内壁探查法置入下颈椎弓根螺钉的技巧并评价其准确性及安全性。方法:2014年1月至2016年10月采用自行设计带角度仪导向器结合钉道内壁探查法对11例患者置入下颈椎椎弓根螺钉,其中男7例,女4例;年龄32~63岁,平均48.1岁;脊髓型颈椎病4例,颈椎骨折脱位4例,无骨折脱位颈脊髓损伤1例,寰枢椎骨折脱位2例。术前CT测量出目标椎弓根直径、理想进钉点及矢状面夹角和横断面内倾角。术中使用自行设计带角度仪导向器严格控制进钉角度,结合探查钉道内壁作为安全置钉标志。术后观察患者有无脊髓及椎动脉损伤表现,复查CT评价椎弓根螺钉位置,并将螺钉准确性进行分级,计算螺钉优良率。结果:11例患者共置入71枚下颈椎弓根螺钉,均未出现手术所导致的脊髓及神经根损伤症状,亦无椎动脉损伤症状。术后CT评估螺钉位置并进行分级:0级52枚,1级13枚,2级4枚,3级2枚。螺钉位置良好率91%。6枚误置螺钉,内壁穿破4枚,2枚穿破外壁。结论:钉道内壁探查法置入下颈椎弓根螺钉安全可靠,但有一定的学习曲线。术中探查出钉道内壁及使用角度仪导向器控制进钉角度是置钉关键。     

腰椎不同深度置入椎弓根螺钉对把持力的影响

目的：观察椎弓根螺钉在相同水平角度（TSA 角为0°）、相同矢状角度（SSA 角为0°）不同深度时置入单个椎体对把持力的影响,为临床置钉提供理论依据。方法采用6个月龄猪 L2新鲜标本共16个椎体,将32侧椎弓根分4组,按不同深度分70％组、75％组、80％组、85％组分别置入椎弓根螺钉,自动记录仪记录下螺钉载荷-位移的变化曲线,测出最大轴向拔出力及最大拔出能量。结果80％组椎弓根螺钉最大拔出力及最大拔出能量明显大于70％组（P ＜0．05）,75％组与85％组椎弓根螺钉的最大拔出力及最大拔出能量与70％组比较差异无统计学意义（P ＞0．05）。结论不同深度置钉对椎弓根螺钉的把持力随置钉深度的增加而逐渐增大。     

SSA角度与椎弓根螺钉拔持力的相关性研究

目的 观察椎弓根螺钉不同矢状成角(SSA)置入后单个椎体的拔钉生物力学研究,为临床置钉提供理论依据.方法 采用6月龄猪新鲜L1共12个椎体标本,将24侧椎弓根分3组,按矢状成成角0°组、-20°组、10°组置入椎弓根螺钉,测出最大轴向拔出力.结果 -20°组椎弓根螺钉拔出力及拔出能量最大,0°组螺钉拔出力及拔出量最小,10°组界于二者之间,3组之间最大拔出力及拔出能量两两比较P＜0.05,提示各组之间差异均有统计学意义.结论 矢状面成角置钉对螺钉的把持力大于0°角钉.随置钉角度的增加把持力也逐渐增大.     

不同矢状角度置入椎弓根螺钉的拔钉生物力学研究

目的 观察椎弓根螺钉不同矢状成角置入后单个椎体的拔钉生物力学特点,为临床置钉提供理论依据.方法 采用猪新鲜L1共12个椎体标本,将24侧椎弓根分三组,按不同矢状成角0°组、10°组、-20°组置人椎弓根螺钉,测出最大轴向拔出力.结果 -20°组椎弓根螺钉拔出力及拔出能量最大,0°组最小,10°组界于二者之间;三组之间最大拔出力及拔出能量两两比较P＜0.05.提示各组之间差异均有统计学意义.结论 矢状面成角置钉对螺钉的把持力大于0°角置钉,随置钉角度的增加,螺钉把持力也增大.     

数字矩阵建模在寰椎椎弓根螺钉通道研究中的应用

目的 观察寰椎椎弓根通道在不同水平面角(TSA)、矢状面角(SSA)的变化规律,以及使用不同规格螺钉的变化规律,探讨数字矩阵建模在术前设计寰椎椎弓根螺钉进钉方案中的作用. 方法 将9位健康成人受试者(男5例,女4例;年龄26 ～ 70岁,平均45岁)的寰椎CT连续断层扫描数据导入Mimics 10.0l软件,三维重建后用.dwg文件导入3dnax2009.确定三维参照坐标和进钉点,用3dmax中参考建模命令建立17×17×2,间距2.5°,TSA 0 ～ 40°、SSA 0～40°,共578个元素模拟椎弓根螺钉矩阵模型,观察当模拟螺钉进钉角度、直径、长度变化时椎弓根螺钉通道的变化规律. 结果 TSA、SSA均明显影响左、右侧螺钉进钉长度,差异有统计学意义(P＜0.05).TSA=0°、SSA=10°时螺钉长度最佳[左侧平均为(1.91 ±0.26) mm,右侧平均为(1.51±0.29)mml.直径为3.5 mm、长为22 mm的螺钉在寰枢椎进钉数目较直径为3.5 mm、长度为26 mm的螺钉多,直径为3.5mm、长度为22mm螺钉在寰枢椎进钉数目较直径为4.0 mm、长度为22 mm的螺钉多,差异均有统计学意义(P＜0.05). 结论 利用数字矩阵建模能够简化复杂逆向建模可以全方位观察不同TSA、SSA、螺钉规格变化时椎弓根通道的变化规律.术前设计时不仅需要综合考虑椎弓根螺钉本身的TSA、直径及长度,而且要考虑SSA,以确定个性化的进钉方案.     

基于结构光扫描的脊柱三维手术导航系统的试验研究

目的 研究基于结构光扫描的脊柱三维手术导航系统(结构光导航)的可操作性,同时比较结构光导航与传统的CT三维导航及徒手操作的准确性差异.方法 32侧小牛腰椎椎弓根标本通过结构光导航系统行椎弓根螺钉置入;40侧小牛腰椎椎弓根标本通过CT导航系统行椎弓根螺钉置入;32侧小牛腰椎椎弓根标本行徒手椎弓根螺钉置人.术后行CT扫描及三维重建,计算螺钉穿孔率、水平面角度(sransverse section angle,TSA)、矢状面角度(sagital section angle,SSA)及椎弓根螺钉偏距.结果 所有标本均成功获得椎弓根螺钉置入.结构光导航组、CT导航组、徒手组的穿孔率分别为6%(2/32),5%(2/40),25%(8/32).导航组之间螺钉穿孔率差异无统计学意义,导航组与徒手组相比螺钉穿孑率差异有统计学意义.结构光导航组术中、术后SSA及TSA差值分别为2.58°±2.74°和4.26°±5.2°,CT导航组分别为2.95°±2.61°和3.13°±2.75°,两组间术中、术后SSA差值及TSA差值比较,差异无统计学意义.导航组之间椎弓根偏距术中、术后差异无统计学意义,均低于徒手组.结论 结构光导航系统是一种新的、临床操作性强的导航系统,较传统徒手椎弓根置钉更为安全,其置钉准确性与CT导航无明显差异.

Abstract：

Objective To introduce a new spinal surgery navigation system based on structured light scanning(structured light navigation system,SLNS),and to compare accuracy of pedicle screw placement using SLNS,CT based navigation system and free hand technique.Methods Thirty-two calf vertebral pedicles,40 and 32 were placed with pedicle screws using SLNS,CT navigation system,and free hand technique,respectively.The pedicle breakage ratio,transverse section angle (TSA),sagittal section angle (SSA),screw offset deviation of each screw were detected according to CT images.Results The pedicle breakage ratio of pedicle screws in SLNS group,CT navigation group and free hand group were 6%(2./32),5%(2/40),25%(8/32),respectively.The difference between each of the two navigation groups and free hand group were statistically significant regarding frequency of screw misplacement.The difference between the two navigation systems was not obvious.The average SSA error and TSA error in SLNS group were 2.58°±2.74° and 4.26°±5.20°.For CT navigation group,they were 2.95°±2.61° and 3.13°±-2.75°.There was no statistical difference between the two navigation methods for the SSA or TSA error.There was no statistical difference in offset deviation among SLNS group,CT navigation group and free hand group.Conclusion The SLNS is a new and practical navigation system,which has similar accuracy with CT navigation system.     

骶髂关节空心钉内固定导向器的研制及临床应用

目的 自行设计并研制一种骶骼关节空心钉内固定导向器,以期提高S1椎弓根空心钉置入的成功率及置入质量。方法 自行设计并研制的骶髂关节空心钉内固定导向器由带有测量长度的定位器、带有角度刻度表的水平面S1椎弓根空心钉置入角（TSA）、矢状面置入角(SSA)调节器及固定螺丝等组成。2006年6月至2009年10月共收治15例不稳定型骨盆骨折累及骶髂关节者,男6例,女9例;年龄19 ～ 60岁,平均45.6岁。不稳定型骨盆骨折经骶髂关节韧带3例,经骶骨Ⅰ区5例,累及骶骨Ⅱ区5例,累及骶骨Ⅲ区2例。15例患者均采用骶髂关节空心钉内固定导向器引导术中空心钉的操作,共置入18枚空心钉。结果 术后CT及X线片示18枚空心钉置入位置准确,与术前设计相比,具有相同或相近的TSA及SSA。结论 骶骼关节空心钉内固定导向器设计合理,使用方便,能提高S1椎弓根空心钉置入的准确性及置入质量,且可显著减少C型臂X线机的透视次数。     

胸椎椎弓根形态测量研究

目的:观察不同节段胸椎椎弓根形态特征,探讨其临床意义。方法:测量40具国人胸椎标本的椎弓根横径、矢状径、矢状面夹角、椎弓根间距、椎弓根后缘皮质到椎体前缘皮质距离及椎弓根-椎板夹角,观察椎弓根后缘中点与相应横突根部的关系。结果:（1）除T1外,各节段椎弓根矢状径均明显大于横径（P<0.01）;（2）椎弓根矢状面夹角从T1到T9逐渐减小,T10以下为负角;（3）椎弓根后缘皮质沿其轴线到椎体前缘的长度从T1到T7逐渐增加,T7到T12基本相同;（4）T1与T12椎弓根螺钉拟进钉点位于横突根部中点,T2及T11位于横突根部中上1/3点,其余各节段均位于横突根部上缘。结论:进行胸椎椎弓根螺钉固定时,应根据不同节段椎弓根形态特点,结合X线片或CT片,选择相应的螺钉直径、长度、进钉部位及方向。     

自行研制的经皮胸腰椎椎弓根置钉三维定位器应用的可行性实验研究

目的 通过与"徒手"置钉进行比较,探讨自行研制的经皮胸腰椎椎弓根置钉三维定位器辅助在脊柱标本上进行经皮椎弓根穿刺的可行性.方法 对新鲜保留皮肤软组织的脊柱标本2具(32个椎体)行胸腰椎序列CT扫描,使用Mimics 13.1软件确定椎弓根轴心片,测定水平面椎弓根螺钉植入角度(TSA)及矢状面椎弓根螺钉植入角度(SSA).定位皮肤穿刺点,对应调节水平面及矢状面角度指示器刻度指导穿刺.椎弓根随机分为两组:一侧为自行研制的经皮胸腰椎椎弓根置钉三维定位器辅助组(定位器组),对侧为"徒手"置钉组(徒手组).定位器组在定位器及X线辅助下穿刺,徒手组在C型臂影像增强系统辅助下予"徒手"技术穿刺,置入克氏针,C型臂X线机证实穿刺成功.行椎弓根CT扫描,测量2种方法穿刺的实际TSA角及SSA角,将术前测定的椎弓根TSA角及SSA角与术后实际TSA角及SSA角对比,计算偏差率;比较两组的偏差率和X线曝光次数.结果 定位器组和徒手组的穿刺TSA角偏差率平均分别为10.83%±3.41%和19.08%±4.21%,差异有统计学意义(P＜0.05);定位器组和徒手组的穿刺SSA角偏差率平均分别为13.13%±4.37%和21.15%±6.78%,差异有统计学意义(P＜0.05).定位器组和徒手组接受X线辅助的次数平均分别为(3.0±1.2)次和(5.3±1.6)次,差异有统计学意义(P＜0.05).结论 与"徒手"置钉相比,应用自行研制的经皮胸腰椎弓根置钉三维定位器可有效提高手术准确度、降低手术难度、减少X线暴露.

Abstract：

Objective To test a self-designed 3-D guiding instrument for percutaneous insertion of thoracolumbar pedicle screws in cadaveric vertebrae. Methods Two fresh cadaveric vertebral specimens with skin and soft tissue were used first for standard CT lateral scanning ofT1 to L4.Software Mimics13.1 was used to create axial images of pedicles of vertebral arch.The points of percutaneous insertion of thoracolumbar pedicle screws,transverse screw angles (TSA) and sagittal screw angles (SSA) were measured.Thirty-two vertebral bodies were divided randomly into 2 equal groups for guiding instrument insertion and manual insertion with the aid of C-arm fluoroscopy.The quality of insertion was evaluated by postoperative CT scans.Angular deviations were determined by comparing the preoperative and postoperative TSA and SSA for the 2 groups.X-ray exposures were also compared between the 2 groups. Results The TSA angular deviation rate was ( 10.83 ± 3.41 ) ％ for the guiding instrument insertion group and ( 19.08 ± 4.21 ) ％ for the manual insertion group.The SSA angular deviation rate was (13.13 ±4.37) ％ for the guiding instrument insertion group and (21.15 ± 6.78) ％ for the manual insertion group.The guiding instrument insertion group needed 3.0 ± 1.2 X-ray exposures while the manual insertion group had 5.3 ± 1.6 X-ray exposures.All the differences were statistically significant. Conclusion The 3-D guiding instrument can facilitate the percutaneous insertion of the thoracolumbar pedicle screws by improving operation accuracy and reducing operation difficulty and X-ray exposures as well.     

Accuracy of fluoroscopically assisted laser targeting of the cadaveric thoracic and lumbar spine to place transpedicular screws

A simple and inexpensive method was developed to obtain a coaxial view of the pedicles to assist with screw insertion. The authors evaluated the accuracy of this device to place transpedicular vertebral screws in a human adult cadaver model. A dual radiation targeting system, a laser targeting system for fluoroscopically guided procedures, was developed to provide an accurate surface entry point and angle of approach to radiographic landmarks. After fluoroscopic cross-hair target localization of the coaxial view of the pedicle, X-ray radiation is turned off and the laser beam allows the surgeon to guide the screw through the pedicle. Nine cadaver spines were removed and mounted. Three surgeons, inexperienced in the technique of pedicle screw placement, fitted instruments to 184 pedicles between L5 and T5. A total of 83 lumbar and 101 thoracic pedicles underwent screw placement. After specimen dissection, the degree and location of any screw perforation were measured by direct inspection. Three screws perforated a pedicle, for an error rate of 1.6%. Two lumbar screws (2.4% error) and one thoracic screw (1% error) perforated the pedicle. No screw was more than 1 mm outside the pedicle. Five other screws, four in the thoracic spine and one in the lumbar spine (error rate of 2.7%) were directed too far laterally and perforated the lateral vertebral body. This low rate of pedicle wall cortical perforation by inexperienced surgeons compares favorably with much higher pedicle perforation rates by experienced surgeons when no imaging was used. In conclusion, this in vitro model using a dual radiation targeting system assisted with the accurate placement of transpedicular vertebral screws with minimal radiation exposure.     

Pedicle morphology of the thoracic spine in preadolescent idiopathic scoliosis: magnetic resonance supported analysis

Although several studies have been reported on the adult vertebral pedicle morphology, little is known about immature thoracic pedicles in patients with idiopathic scoliosis. A total of 310 pedicles (155 vertebrae) from T1 to T12 in 10–14 years age group were analyzed with the use of magnetic resonance imaging and digital measurement program in 13 patients with right-sided thoracic idiopathic scoliosis. Each pedicle was measured in the axial and sagittal planes including transverse and sagittal pedicle width and angles, chord length, interpedicular distance and epidural space width on convex and concave sides of the curve. The smallest transverse pedicle widths were in the periapical region and the largest were in the caudal region. No statistically significant difference in transverse pedicle widths was detected between the convex and concave sides. The transverse pedicle angle measured 15.56° at T1 and decreased to 6.32° at T12. Chord length increased gradually from the cephalad part of the thoracic spine to the caudad part as the shortest length was seen at T1 convex level with a mean of 30.45 mm and the largest length was seen at T12 concave level with a mean of 41.73 mm. The width of epidural space on the concave side was significantly smaller than that on the convex side in most levels of the curve. Based on the anatomic measurements, it may be reasonable to consider thoracic pedicle screws in preadolescent idiopathic scoliosis.     

青少年脊柱侧凸患者胸椎椎弓根螺钉置入的准确性和安全性评价

目的：探讨青少年脊柱侧凸患者胸椎椎弓根螺钉置入的准确性和安全性，以减少相关手术并发症。方法：32例青少年脊柱侧凸患者术前均对畸形脊柱进行标准俯卧位CT加密扫描，测量进钉点至椎体前缘的深度、进针角度、椎弓根直径和椎体的旋转角度，根据测得数据确定椎弓根螺钉置入的深度和方向，置入螺钉后再行脊柱全长X线片及CT扫描评价置钉的准确性和安全性。结果：32例共置入226枚胸椎椎弓根螺钉，术后CT加密和X线片观察到205枚螺钉（90．7％）完全在椎弓根皮质骨内。10例21枚螺钉（9.3％）发生错置，7枚螺钉（3．1％）偏外，5枚螺钉（2．2％）偏前外侧（其中2枚螺钉靠近节段血管），4枚螺钉（1．8％）偏下，4枚螺钉（1．8％）直径过大导致椎弓根内壁膨胀内移，1枚螺钉（0．4％）误入椎管导致完全性脊髓损伤。T1～T4错置12枚（18．2％），T5～T12错置9枚（6．1％）；凸侧椎根螺钉置入的准确率为93．8％，凹侧为83．1％。结论：脊柱畸形患者术前应常规采用标准俯卧位CT加密扫描，根据扫描图像测得的相关数据可为术中准确置入椎弓根螺钉提供重要参考依据。在青少年脊柱侧凸患者胸椎椎弓根螺钉置入有一定的误置率，螺钉发生错置多见于上胸椎和凹侧．术中应高度重视。     

胸椎经关节突关节椎弓根螺钉固定的可行性研究

 目的明确胸椎后路经关节突关节椎弓根螺钉固定的解剖学可行性和技术参数.为临床应用提供参考。方法取 20具胸椎标本.仔细解剖胸椎的后侧和前侧方.以清楚地暴露胸椎椎板和椎弓根。以椎板下缘向上、外缘向内各 7 mm为进钉点.在 T_1.2、T_5.6、T_9.10直视下置入经关节突关节椎弓根螺钉.通过直接的置钉和 CT重建.观察胸椎后路经关节突关节椎弓根螺钉实际置钉的可行性.测量经关节突关节椎弓根螺钉内固定进钉角度和钉道长度。结果所有胸椎后路经关节突关节椎弓根螺钉均由上位胸椎下关节突经关节突关节.进入下位胸椎的椎弓根.成功置入下位胸椎的椎体内。重建 CT测量发现螺钉在横断面的外倾角度为 2.1°±0.7°.在矢状面的尾倾角度为 41.4°±3.2°.在各节段间略有不同.但差异无统计学意义。平均的螺钉钉道长度为(40.6±4.9) mm.钉道长度由上胸椎向中、下胸椎呈逐渐增加趋势.差异有统计学意义(F=74.09, P<0.01)。结论胸椎后路经关节突关节椎弓根螺钉具有解剖学可行性.可以作为胸椎椎弓根螺钉固定的一种补充内固定方法.但置钉时要求较高的准确性。     

Computer analysis of the safety of using three different pedicular screw insertion points in the lumbar spine in the Chinese population

To help decide the best starting point for lumbar spine pedicle screw insertion in the Chinese population using three different techniques (Roy-Camille, Magerl, and Du). Three-dimensional CT reconstructions were created from 40 adult lumbar vertebral segments. Three different starting points for lumbar pedicle screw insertion were used. The direction of the pedicle screw through each hole was simulated on three-dimensional reconstructed images. Precise CT measurements were made to assess the distance from the simulated screw and the medial and lateral pedicle walls at the smallest transverse section of each pedicle. To measure a pedicle transverse section angle (TSA) lines were drawn on a CT scan in the direct axis of the pedicle, tangential to the medial, and separately lateral, walls of the pedicles at the isthmus. The angle these lines made with an anterior to posterior line, which directly bisected the mid-portion of the vertebral body was called the TSA. The greater the difference between the TSA between the medial and lateral walls provides the greatest flexibility for the insertion angle of the pedicle screw. Additionally, the distance from a line drawn in the direct central axis of the pedicle was measured from the point of exit from the pedicle to the entry point of each of three insertion techniques (Du, Mageral, and Roy-Camille), to help understand potential risk factors. There were statistically significant differences between the distances from the entrance point to the direct pedicle axis among the three methods (P < 0.001). Du’s insertion point was the shortest from L1 to L4. The distances measured following Magerl’s technique were shortest at L5 (P < 0.05). There was no significant difference of the safe range of the TSA between the three methods from L1 and L2 (P > 0.05), but significant differences at L3, L4, and L5 (P < 0.05). At L3 and L4 the safe ranges of TSA using Du and Magerl’s methods were significantly larger than those measured by Roy-Camille (P < 0.05). At L5 the safe ranges of TSA for the Magerl technique were the greatest among the three methods (P < 0.05). These results demonstrate that Du’s method provides the safest starting point to place pedicle screws from L1 to L4, as its distance from the entrance point to the pedicle axis is the shortest and the safe range of TSA the largest of the three techniques. Magerl’s technique can be safely used in the pedicles from L3 to L5, and is the safest choice at L5. Roy-Camille’s technique is most applicable at L1 and L2, but has the highest risk when applied from L3 to L5.     

胸腰椎椎弓根钉置入导向器的设计及应用实验

目的：设计一种新型椎弓根钉置入导向装置，以期减少椎弓根钉置入的失败几率。方法：术前CT扫描拟置钉椎体，确定椎弓根轴线。右侧以导向器辅助钻孔，左侧徒手钻孔。钻孔后孔内置克氏针，椎弓根环绕钢丝，摄正侧位X线片，评价其准确程度。结果：导向器组36个椎弓根有2个椎弓根(5．6％)穿破，徒手组36个椎弓根有8个椎弓根(22％)失败。经统计学处理显示，两组结果有显著性差异。结论：应用新型导向器，能明显降低下胸椎及腰椎椎弓根钉置入中的失败率。