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。     

骶骨椎弓根及侧块的应用解剖研究

【摘要】 目的：研究骶骨椎弓根及侧块的解剖学结构特点,为骶骨椎弓根和侧块螺钉内固定技术应用提供理论依据。方法：随机选择60例成人患者骶尾骨螺旋CT图像资料,应用三维重建技术确定骶骨椎弓根和侧块的进钉点,测量骶骨椎弓根和侧块的螺钉置入钉道长度和角度。选择15例成人尸体标本进行大体解剖,确定骶骨椎弓根和侧块的进钉点,并测量螺钉置入的钉道长度和角度。结果：S1～S5的椎弓根和侧块变化较大但左右对称,椎弓根进钉点位于横突中线与骶后孔中点连线交点,侧块进钉点位于横突中线与骶外侧嵴交点内侧,椎弓根钉的钉道角度外倾约2     

从X线片上设计椎弓根螺钉入钉点的探讨

目的：探讨胸腰段椎弓根螺钉入钉点的选定方法。方法：1996年一2001年通过测量胸腰椎标推前后位X线片上椎弓根椭圆形投影的中心点与上一椎同侧下关节突下极及外侧缘的相互位置关系，以该下关节突为参照物，个体化选定椎弓根螺钉入钉点，临床应用42例。结果：所有病例术后拍X线片复查，椎弓根螺钉置入位置良好，骨折椎体恢复正常高度，椎体滑脱得以复位。结论：根据胸腰段脊柱标推前后位X线片上椎弓根与同侧上一椎下关节突投影的相互位置关系，以该下关节突为参照钧，动态选定椎弓根螺钉入钉点，是一个良好的方法。     

青少年胸椎椎弓根影像学特征及其临床意义

目的 :探讨青少年胸椎椎弓根影像学特征及其临床意义。方法 :随机选择正常青少年 42人 ,平均年龄12 .4岁 ,摄胸椎X线片 ,对 2 7人行全胸椎椎弓根CT扫描 ,分别测量各节段椎弓根横径、螺钉进钉点和深度 ,以及椎弓根轴线与矢状面夹角等 ,并根据X线测量方法 ,对 10 3例脊柱侧凸患者进行节段椎弓根螺钉器械矫正。结果 :正常C4椎弓根横径最小 (3 .9± 0 .66)mm ,胸椎椎弓根钉进钉点均位于横突根部上缘与中点之间 ,T11、12 椎弓根矢状角为负角 ,其余为正角。 10 3例患者共置入 10 82枚胸椎椎弓根螺钉 ,穿透椎弓根内外侧及椎前皮质的螺钉分别占 18.6%、 14 .5 %和 2 .1% ,仅 1例患者出现了与椎弓根穿透内侧皮质有关的神经系统症状 ,无其他相关并发症。结论 :认真阅读X线片 ,了解与掌握不同节段椎弓根形态特征及周围解剖关系 ,有助于进行正确的胸椎椎弓根螺钉置入。     

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。     

枢椎以横突后支与下关节突交界处为解剖标志行椎弓根置钉的应用解剖研究

目的 :探讨枢椎以横突后支与下关节突交界处为解剖标志行椎弓根置钉的可行性,为临床应用提供参考。方法:30具湿性成人颈椎尸体标本,显露并以枢椎横突后支与下关节突外侧缘交界处作为参照点标志。经该解剖标志作水平线,以椎弓根内、外侧缘与侧块交界处连线的中点作纵垂线,以两线的交点偏外1~2mm处为进钉点。分别测量枢椎横突后支的宽度,进钉点与该解剖标志、C2神经根、横突孔内下壁和椎管内侧壁的距离。取上述进钉点,经枢椎双侧椎弓根以内倾角25°~30°、头倾角20°~25°共置入60枚螺钉,再行CT扫描观察钉道的完整性,测量置入螺钉的内倾角和头倾角,统计螺钉偏置率。结果:所有解剖参数及螺钉角度左、右侧比较差异均无统计学意义(P0.05),双侧数据合并后计算总体平均数值。枢椎横突后支的宽度为5.13±0.15mm,进钉点与解剖标志、C2神经根、横突孔内下壁和椎管内侧壁的距离分别为5.73±0.62mm、4.04±0.21mm、5.32±0.49mm和4.94±0.38mm。螺钉内倾角和头倾角分别为28.4°±3.1°和22.5°±2.9°。60枚螺钉中,共有4枚螺钉偏置进入横突孔或椎管,螺钉偏置率为6.7%(4/60);4枚螺钉过长穿破椎体前缘骨皮质。结论:枢椎以横突后支与下关节突交界处作为椎弓根置钉进钉点的参照点解剖标志是可行的,但因解剖差异仍存在螺钉误置的可能。     

X线分步监测胸腰椎椎弓根螺钉植入的实验研究

[目的]探讨X线分步监测胸腰椎椎弓根螺钉准确置入的可行性。[方法]选8具T9～L5脊柱标本，随机分A、B两组，每组4具。A组按X线分步监测方法置入椎弓根螺钉。CT扫描测量椎弓根一半长、全长及螺钉通道长度和椎弓根e角及f角。当导针进至深度为椎弓根一半时，标准正位片导针远端到达椎弓根投影中线为符合标准；当导针进至深度为椎弓根全长时，腰椎到达椎弓根投影3／4处为符合标准，而胸椎到达椎弓根投影的1／2与3／4的中线处为符合标准；导针进入椎体，调整X线机臂，侧位片观察导针深度及f角。按照导针轨道植入椎弓根螺钉。B组为对照组，按传统X线监测方法置入椎弓根螺钉。通过观察两组螺钉的位置，评估A组方法的准确性。[结果]A组植入螺钉72枚：68枚位于椎弓根内，左右螺钉基本对称；4枚穿破椎弓根，穿破率为5．56％。B组亦为72枚：53枚位于椎弓根内；19枚穿破椎弓根，穿破率为26．38％。A组优于B组（P〈0．001）。[结论]X线分步监测胸腰椎椎弓根螺钉的置入，可克服传统X线平片的局限性及减少置钉过程中的人为因素干扰，在一定程度上可使两侧椎弓根螺钉对称植入，提高了螺钉置入的准确性。     

颈椎经关节椎弓根螺钉固定与标准椎弓根螺钉固定的生物力学比较

目的 比较颈椎经关节椎弓根螺钉固定和标准椎弓根螺钉固定的拔出强度.方法 取10具新鲜尸体颈椎标本(C_3～T_1),游离成三个颈椎运动节段(C_(3,4),C_(5,6),C_7T_1).在椎体两侧随机进行经关节椎弓根螺钉固定或标准椎弓根螺钉固定,置入直径3.5 mm皮质骨螺钉.经关节椎弓根螺钉固定以上位椎骨侧块外下象限中点为进钉点,在直视椎弓根下,螺钉在冠状面内倾约45°、矢状面尾倾约50°.由上位椎骨下关节突经关节突关节、下位椎骨的椎弓根,进入下位椎骨的椎体内.标准椎弓根螺钉固定以侧块外上象限中点为进钉点,在直视椎弓根下,螺钉方向参考CT测量结果 ,尽量与椎弓根倾斜角度保持一致,在横断面上内倾约45°、矢状面上螺钉指向椎体的上1/3.在生物力学试验机上行拔出强度试验,比较两种螺钉固定的最大轴向拔出力.结果 颈椎经关节椎弓根螺钉固定平均最大轴向拨出力为(694±42)N,标准椎弓根螺钉固定为(670±36)N,两者比较差异有统计学意义(P<0.05).结论 颈椎后路经关节椎弓根螺钉固定的拔出强度大干标准椎弓根螺钉固定,从生物力学强度方面考虑经关节椎弓根螺钉固定可以作为标准椎弓根螺钉固定的一种补充方法.     

以关节突关节面及棘突为参照定位腰椎椎弓根的临床置钉研究

目的探讨以关节突关节面及棘突为参照定位腰椎椎弓根并应用于临床置钉的准确性和可行性。方法测量关节突关节面后缘距离椎弓根轴线的水平距离（D）;测量上位椎节下关节突下缘水平线与本位椎节椎弓根轴线的垂直距离（K）;测量L1-L5椎节棘突上缘中段切线与椎弓根轴线夹角即头倾角（α角）。统计分析比较D值L1-L5椎节间的差异性;统计分析比较K值L1-L5椎节间差异性。使用关节突关节面-棘突法进行临床置钉,术后行CT检查评价螺钉位置,分析关节突关节面-棘突法置钉准确率、风险率、绝对风险率。结果模型D值数据与CT影像D值数据相比较,L1-L4椎节差异性无统计学意义,L5椎节差异性有统计学意义。经统计学分析,L1-L5不同椎节间K值差异性无统计学意义。所有患者住院及随访期间均未出现神经血管损伤并发症以及断钉、断棒、螺钉松动等情况。结论使用关节突关节面-棘突法置钉,准确率高,风险率低,满足个体化置钉同时克服部分骨骼变异,为临床手法置入腰椎椎弓根螺钉提出了一种新方法。     

个体化导航模板辅助腰椎椎弓根螺钉置钉准确性实验研究

目的:探讨个体化导航模板辅助腰椎椎弓根螺钉置入的准确性.方法:根据10具尸体腰椎(L1～L4)标本术前CT资料,利用逆向工程原理及快速成型技术设计制造出个体化导航模板,在尸体标本上进行个体化导航模板辅助腰椎椎弓根螺钉的置入手术,术后行CT断层扫描评价螺钉在椎弓根及椎体内的位置.结果:共应用40个个体化导航模板,辅助置入腰椎椎弓根螺钉80枚.CT扫描发现所有螺钉进钉点准确,进钉方向适当:全部螺钉均准确置入相应椎弓根及椎体内,无穿破椎弓根皮质及椎体前方的螺钉.结论:个体化导航模板辅助腰椎椎弓根螺钉置钉准确性高,操作简单,为腰椎椎弓根螺钉的准确置入提供了一种新的可供选择的方法.     

Comparison of the safety of three methods of lumbar transpedicular screw fixation

Objective: To choose a proper method of lumbar transpedicular screw fixation at different lumbar levels among the three methods (Roy-Camille's method, Magerl's method and Du's method) in the Chinese population. Methods: Three-dimensional ( 3-D ) images were reconstructed with image data of 42 adult lumbar segments that were scanned by Electron Beam CT. The three methods of lumbar pedicle screw fixation were simulated on the 3-D reconstructed images and the parameters of implanting pedicle screws were measured. Results : There was statistically significant difference at the distance from the entrance point to the pedicle axis between the three methods (P<0.001). The distances measured by Du's method were shortest from L1 to L4, and the distances measured by Magerl's method were shortest at L5 (P<0.05). There was no significant difference from L1 to L2 (P >0.05) but significant difference from L3 to L5 at inserting safe ranges of TSA (transverse section angle) was found between the three methods (P<0.05). From L3 to L4, the inserting safe ranges of TSA measured by Du's and Magerl's methods were significantly larger than that measured by Roy-Camille's method (P<0.05), but there was no significant difference between them (P > 0.05). At L5, the inserting safe ranges of TSA measured by Magerl's method were largest among the three methods (P <0.05). Conclusions: Among the three methods, Du's method is the best choice from L1 to L4 because its distance from the entrance point to the pedicle axis is shortest and the safe range of TSA is largest: Magerl's method can be used from L3 to LS and is the best choice at L5; Roy-Camille's method is applicable at L1 and L2.     

Axial computed tomography of the pedicle in the lower cervical spine

Using axial computed tomography (CT), we measured pedicle width, pedicle axis length, pedicle transverse angle, and distance between screw entry point and vertebrae midline in the cervical spines (C3-C7) of 40 patients. All measurements were greater in men than in women, and we noted significant sex differences at most levels of pedicle inner and outer widths (P < or = .05 or P < or = .01). Mean pedicle inner and outer widths for all levels and all patients ranged from 2.3 to 3.0 mm and from 5.0 to 6.0 mm, respectively. Mean distances between screw entry point and vertebrae midline ranged from 22.2 to 23.7 mm. Results of this study-along with axial CT measurements of individual pedicle diameter, pedicle transverse angle, and screw entry point-would be useful when considering and performing transpedicular screw fixation in the cervical spine.     

螺旋CT个体化测量辅助下颈椎椎弓根置钉的实验研究

目的：探讨螺旋CT测量辅助下颈椎椎弓根个体化置钉的准确性。方法：成人颈椎标本10具行螺旋CT扫描重建，在其多平面截面图像上设计出理想进钉路线，此路线在后方侧块上的投影点（O点）即为理想的进钉点，测量出O点与侧块外缘的距离（HO），或到横突根部的距离（HT），与侧块下缘的距离（HL），或与侧块上缘的距离（HU）。同时测量此路线与椎体中轴线的夹角（Am）以及与椎体上终板的夹角（AE）；测量椎弓根峡部松质骨核心的长径（IL）与短径（IS），并测量其向内倾斜角度（f）。在标本上依据上述测量得到的数据找出椎弓根内固定的进钉点即O点。并根据测量的角度确定进钉方向后插入克氏针模拟置钉。将置钉后的标本进行CT扫描，判断其准确性。结果：共置入98枚克氏针，89枚（90．8％）完全在椎弓根内，9枚（9．2％）穿破椎弓根。结论：利用螺旋CT测量的数据辅助下颈椎椎弓根置钉有较高的准确性，但仍有一定的椎弓根穿破率。     

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.     

以棘突定位胸腰椎经椎弓根内固定的应用解剖学研究及意义

目的 研究胸腰椎棘突与椎弓根的解剖关系,提供相关数据为椎弓根穿钉确定一种新的解剖定位点。方法 测量30具正常成人尸体的干燥胸腰椎标本,80个正常成人胸腰椎X线片及60人胸腰椎CT片(T_(10)～L_5节段)之棘突上缘根部至椎弓根上缘、下缘及中轴线的距离。用5具新鲜尸体做实验室手术模拟。结果 获得了相关解剖学数据,据所得数据设计螺钉入点。实验室80个螺钉全部穿钉成功,并成功临床应用6例。结论 该研究揭示了棘突与椎弓根的解剖关系,为经椎弓根手术提供了一种新的解剖学定位方法。     

胸腰椎棘突上缘根部与椎弓根关系的解剖学研究及意义

目的：研究胸腰椎棘突与椎弓根的解剖关系，提供相关数据为椎弓根穿钉确定一种新的解剖定位点。方法：测量30具干燥胸腰椎骨标本(T10-L5节段)之棘突上缘根部至椎弓根上缘、下缘及中轴线的距离。用5具新鲜尸体做实验室手术模拟。结果：获得了相关解剖学数据，根据所得数据设计螺钉入点。实验室80个螺钉全部穿钉成功，并成功临床应用6例。结论：该研究揭示了棘突与椎弓根的解剖关系，为经椎弓根手术提供了一种新的解剖学定位方式。     

Primary lumbosacral stability after open posterior and endoscopic anterior fusion with interbody implants: a roentgen stereophotogrammetric analysis

STUDY DESIGN: After posterior stabilization of the spondylolytic lumbosacral level, mobility of the fused vertebrae could be studied before and after an additional anterior endoscopic interbody fusion using roentgen stereophotogrammetric analysis. OBJECTIVE: To determine the in vivo primary lumbosacral stability of additional anterior interbody fusion after transpedicular screw fixation. SUMMARY OF BACKGROUND DATA: In vitro studies indicate a significant decrease in segmental motion after pedicle screw fixation and additional anterior fusion. Roentgen stereophotogrammetric studies demonstrate the adequacy of transpedicular lumbar instrumentation in posterolateral fusions. There are no studies examining the effect of additional anterior interbody fusion after posterior instrumentation in vivo. METHODS: In this study, 15 patients with low-grade spondylolisthesis at L5-S1 underwent a two-stage open posterior and endoscopic anterior lumbar fusion using carbon fiber (Brantigan I/F) cages. At surgery, tantalum markers were implanted into the fifth lumbar (L5) and the first sacral (S1) vertebra. All the patients were examined by roentgen stereophotogrammetric analysis after the first and second surgical procedures. RESULTS: After implantation of the posterior pedicle system only, the mean intervertebral mobility determined by roentgen stereophotogrammetric analysis was 0.23 mm in the transverse (x), 0.54 mm in the vertical (y), and 1.2 mm in the sagittal (z) axes. After additional anterior endoscopic fusion with carbon cages, the remaining translation between the fused segment L5/S1 decreased to 0.17 mm in the x, 0.16 mm in the y, and 0.44 mm in the z axes. CONCLUSION: Anterior endoscopic lumbosacral fusion significantly increases the primary stability of the posterior fusion with a pedicle system in two axes of motion.     

Analysis of the morphometric characteristics of the thoracic and lumbar pedicles

A total of 2,905 pedicle measurements were made from T1-L5. Measurements were made from spinal computerized tomography (CT) scan examinations and individual vertebral specimen roentgenograms. Parameters considered were the pedicle isthmus width in the transverse and sagittal planes, pedicle angles in the transverse and sagittal planes, and the depth to the anterior cortex in a line parallel to the midline of the vertebral body and along the pedicle axis. There was no significant difference between data obtained from CT scans and specimen roentgenograms. Pedicles were widest at L5 and narrowest at T5 in the transverse plane. The widest pedicles in the sagittal plane were seen at T11, the narrowest at T1. Due to the oval shape of the pedicle, the sagittal plane width was generally larger than the transverse plane width. The largest pedicle angle in the transverse plane was at L5. The posterolateral to anterolateral pedicle axis orientation in the transverse plane, seen at other levels throughout the thoracolumbar spine, reversed at T12. In the sagittal plane, the pedicles angled caudally at L5 and cephaladly from L3-T1. The depth to the anterior cortex was significantly longer along the pedicle axis than along a line parallel to the midline of the vertebral body at all levels with the exception of T12 and T11.     

Morphometric analysis using multiplanar reconstructed CT of the lumbar pedicle in patients with degenerative lumbar scoliosis characterized by a Cobb angle of 30° or greater

Object Although the anatomy of the thoracic pedicle in adolescent idiopathic scoliosis is well known, that of the lumbar pedicle in degenerative lumbar scoliosis is not. The morphometric differences between the pedicles on the concave and convex sides can result in an increased risk of malpositioned pedicle screws. The purpose of this study was to analyze the lumbar pedicle morphology in degenerative lumbar scoliosis using multiplanar reconstructed CT. Methods The study group comprised 16 consecutive patients (1 man and 15 women, mean age 70.9 ± 4.5 years) with degenerative lumbar scoliosis characterized by a Cobb angle of at least 30° who underwent preoperative helical CT scans. The CT data in DICOM format were reconstructed, and the following parameters were measured for each pedicle inside the curves: the inner cortical transverse pedicle width (TPWi) and outer cortical transverse pedicle width (TPWo) and axial angle, all on an axial plane, and the inner cortical minimum pedicle diameter (MPDi) and outer cortical minimum pedicle diameter (MPDo) and cephalocaudal inclination of the pedicle, all on the plane perpendicular to the pedicle axis. The cortical thickness and cortical ratio of the pedicles on the axial plane and the plane perpendicular to the pedicle axis were calculated. Data were obtained for a total of 124 pedicles; L-1, 26 pedicles in 13 patients; L-2, 32 pedicles in 16 patients; L-3, 32 pedicles in 16 patients; L-4, 28 pedicles in 14 patients; and L-5, 6 pedicles in 3 patients. Results Among the target vertebrae, the TPWi, MPDi, and MPDo were significantly smaller and the axial angle was significantly larger on the concave side than on the convex side (TPWi, 6.37 vs 6.70 mm, p < 0.01; MPDi, 5.15 vs 5.67 mm, p < 0.01; MPDo, 7.91 vs 8.37 mm, p < 0.05; axial angle, 11.79° vs 10.56°, p < 0.01). The cortical ratio of the pedicles was larger on the concave side than on the convex side (on the axial plane, 0.29 vs 0.26, p < 0.05; on the plane perpendicular to the pedicle axis, 0.36 vs 0.32, p < 0.01). These differences were most evident at L-4. Conclusions This study demonstrated lumbar pedicle asymmetry in degenerative lumbar scoliosis. The authors speculate that these asymmetrical changes were attributed to the remodeling caused by axial load imbalance and the limited space available for pedicles on the concave side. On the concave side, because of the narrower pedicle diameter and larger axial angle, surgeons should carefully determine screw size and direction when inserting pedicle screws to prevent possible pedicle wall breakage and neural damage.     

胸腰椎经皮椎体成形术单侧穿刺外展角的测量

目的明确胸腰椎经皮穿刺椎体成形术中确定进针终点后单侧穿刺外展角的安全范围。方法收集2011年1月至2012年1月老年骨质疏松性压缩性胸腰椎骨折患者的胸椎、腰椎CT扫描片,随机选择胸椎、腰椎患者各40例(男、女各20例)共520张CT扫描片(胸椎320张、腰椎200张)。采用DICOM Medical ImageViewer Ver 1.01 软件对 CT 片椎体断面相关外展角数据进行测量。首先确定椎体正中线前、中 1/3 交界点为穿刺终点,然后分别测量经椎弓根外缘、内缘至终点的连线与正中线之间的夹角(穿刺最大、最小角度),以及经椎弓根轴线至终点与正中线的夹角(穿刺轴向角)。结果胸椎(T5～T12)最大、最小穿刺角度和轴向角度分别为28.3°～37.4°、17.2°～23.1°和 19.2°～29.9°;腰椎最大、最小穿刺角度和轴向角度分别为 31.9°～44.8°、14.2°～26.5°、和 23.5°～35.4°。男性最大、最小穿刺角度及轴向角度分别为 28.3°～44.5°、14.2°～25.7°和 19.2°～35.4°;女性最大、最小穿刺角度及轴向角度分别为29.3°～44.8°、17.2°～26.5°和23.2°～35.9°。对男性、女性各指标进行比较,差异无统计学意义(P >0.05)。结论对于老年骨质疏松性压缩性胸腰椎骨折患者,单侧经皮穿刺椎体成形术在确定于椎体正中线前、中1/3交界点处为进针终点后,应保持30°左右外展角进针,以确保安全性和最佳成形效果。