非透视下胸腰椎椎弓根螺钉的植入

目的探讨非透视下胸腰椎椎弓根螺钉的植入方法、操作技术及应用疗效。方法对220例胸腰椎骨折脱位患者在非透视下植入椎弓根螺钉,行椎弓根钉棒系统内固定,术中根据第12肋骨、骶骨或骨折的横突等标志确定椎体次序。结果220例中有1例出现椎体次序定位错误。在880枚螺钉中,有95枚出现偏入椎间隙、在腰椎与椎体终板夹角>5°、超出椎弓根下缘及内缘、超出椎体前缘等失误,无诱发新的神经损伤症状或脑脊液漏等并发症,螺钉植入准确率88·75%。结论掌握精确的椎弓根解剖知识及熟练的操作技术,术前进行详细的评估,严格按规范操作,无透视监控下椎弓根螺钉的植入是可行的。     

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。     

L1～S1上终板与棘突夹角的测量

腰椎椎弓根螺钉植入内固定技术在脊柱外科手术中应用越来越广泛.术前仔细地测量正侧位X线片和椎弓根的横断面CT片,以及在术中依靠“C”形臂透视机等辅助设施，才能正确地植入腰椎椎弓根螺钉。对于螺钉植入的进钉点以及螺钉在横断面上应该偏离矢状面的角度，已经有大量的文献进行了详细的描述，     

3种椎弓根螺钉植入法的对比实验研究

目的探讨椎弓根螺钉水平面植入的最佳方法。方法选用15具胸腰椎脊柱标本（T11～L5），随机分三组，分别模拟Roy—Camille、Magerl和节段性差异法先后植入直径5mm、6mm、7mm椎弓根螺钉，观测进钉点和进钉方向与椎弓根中心轴吻合情况、螺钉穿破椎弓根情况和位于椎体内的最大长度。结果Roy—Camille法进钉点多偏椎弓根中心轴内侧，进钉方向与大多数椎弓根E角吻合较差；Magerl法进钉点与腰椎椎弓根中心轴吻合较好，但进钉点方向与E角仍存在差异；节段性差异法与椎弓根中心轴吻合最好。Roy—Camille法螺钉位于椎体内相对较少，Magerl和节段性差异法螺钉位于椎体内较多。植入5mm螺钉时，3种方法的穿破量均极少，植入6mm和7mm螺钉时，穿破量和穿破率相应增加，三者中Roy—Camille法穿破率较高，节段性差异法较低。在胸腰椎交界处无论何种进钉法，使用6mm或7mm时螺钉均有不同程度椎弓根穿破，而在下腰椎使用7mm螺钉的穿破量仍极少或无。结论根据不同节段选用不同直径螺钉、不同进钉点位置和不同进钉方向植入螺钉，节段性差异法植入效果最佳。     

IsoC-3D实时定位导航系统引导植入腰椎椎弓根螺钉34例

目的:探讨IsoC-3D实时定位导航系统在腰椎椎弓根螺钉植入手术过程中的应用.方法:对腰椎滑脱、腰椎失稳、脊柱侧弯、腰椎骨折共34例在IsoC-3D实时定位导航系统引导下完成椎弓根螺钉的植入,共植入椎弓根螺钉132枚,术后进行X线平片及CT扫描掌握螺钉的方向和位置.结果:132枚椎弓根螺钉均未穿破椎弓根,椎弓根螺钉的方向、深度、位置均相当理想,全部病例无硬膜、神经根损伤.结论:IsoC-3D实时定位导航系统可以准确引导腰椎椎弓根螺钉的植入,避免椎弓根螺钉植入相关的并发症.     

微创胸腰椎椎弓根钉内固定术解剖学进展

随着计算机技术和医学影像学的发展，微创胸腰椎椎弓根螺钉技术在微刨脊柱外科领域中已成为脊柱后路固定的一种新的技术手段，经皮椎弓根微创手术已被逐渐应用于对脊柱骨折、腰椎滑脱症、骨质疏松症、经皮椎体强化和后凸成形、腰椎不稳症、椎间盘源性疾病的诊断或治疗。人们对微创胸腰椎椎弓根螺钉内固定的解剖学研究也越来越深入。本文就微创胸腰椎椎弓根钉内固定术的解剖学进展做一综述。     

胸腰椎爆裂型骨折后路治疗体会

目的 评估经后路长节段椎弓根螺钉固定联合减压钛网植入治疗胸腰段爆裂型骨折的效果.方法 单纯后路长节段椎弓根螺钉固定联合减压钛网植入治疗9例胸腰椎爆裂型骨折.根据胸腰椎损伤分类及损伤程度评分系统(Thoracolumbar Injury Classification and Severity Score,TLICS)[...     

与术后CT比较评估术中运用C型臂X线机透视对34例腰椎侧凸的椎弓根固定的置钉情况

目的 探索一种有效方法来识别术中C型臂X线机监测腰椎侧凸椎弓根螺钉的误置.方法 在34例腰椎侧凸畸形的患者中共植入264枚椎弓根螺钉,所有病例手术后均接受CT检查,相比较后总结出3项X线标准可判断术中螺钉的置入位置.结果 比较术后CT和术中X线透视结果发现有7枚螺钉穿破椎弓根内壁.9枚螺钉穿破椎弓根外壁.结论 腰椎侧凸的手术中采用3项X线透视监测标准可有效识别椎弓根螺钉可能发生的误置,并对其及时进行位置修正.     

腰椎滑脱术中椎弓根螺钉置入正误谈

腰椎滑脱术中椎弓根螺钉置入正误谈张波经椎弓根内固定术已普遍用于治疗腰椎滑脱，人们公认椎弓根钉的正确置入是手术成功的关键。虽然人们从投影几何、骨性标志、骨骼测量、电视监测和术中照片等方面进行了研究和应用，但我们认为在腰椎滑脱术中置入椎弓根钉存在一些实际...     

单螺纹和双螺纹椎弓根螺钉抗拔出力比较的临床研究

背景:椎弓根螺钉技术是目前脊柱固定融合最常用的方法。为减少螺钉松动和拔出等并发症,研究人员在螺钉设计等方面进行了不断探索。目的目的:比较单螺纹和双螺纹椎弓根螺钉应用于腰椎内固定术时的螺钉抗拔出力。方法方法:78例行腰椎椎弓根螺钉固定术的患者随机分为两组,所有患者术前均测量髋部骨密度和腰椎骨密度。一组在术中植入单螺纹椎弓根螺钉,另一组则植入双螺纹椎弓根螺钉,测量拧入每枚螺钉时的最大扭矩(以下简称"螺钉扭矩"),比较两组患者的骨密度和螺钉扭矩。结果结果:单螺纹螺钉组患者40例,术前髋部骨密度T值-1.82±0.57,腰椎骨密度T值-2.17±0.77,术中共植入单螺纹椎弓根螺钉150枚,螺钉扭矩(1.03±0.39)Nm。双螺纹螺钉组患者38例,术前髋部骨密度T值-1.90±0.62,腰椎骨密度T值-2.34±0.81,共植入双螺纹椎弓根螺钉150枚,螺钉扭矩(1.45±0.39)Nm。两组患者术前骨密度无明显差异(P>0.05),双螺纹螺钉组的螺钉扭矩显著高于单螺纹螺钉组(P<0.001)。结论结论:相较于单螺纹椎弓根螺钉,双螺纹椎弓根螺钉应用于腰椎内固定术可增加螺钉的抗拔出力。     

带预警装置椎弓根螺锥的临床应用

目的探讨带预警装置椎弓根螺锥在胸腰椎手术应用中的优越性。方法回顾性研究自2010年9月~2011年10月收治的需进行椎弓根钉系统内固定的胸腰椎疾病30例,其中腰椎间盘突出16例,胸腰椎骨折10例,椎体滑脱4例。在减压解除神经压迫或复位椎体的同时利用带预警装置椎弓根螺锥行椎弓根钉固定。结果共置入160枚螺钉,术中及术后X线片评估椎弓根钉置钉准确度为100%,术后三维影像评估螺钉位置准确率为94.4%,螺钉平均置入时间(4.5±0.7)min/枚,未出现螺钉置入相关的近期并发症。结论在胸腰椎手术中应用带预警装置椎弓根螺锥行椎弓根钉置入,可有效提高置钉的精确性、安全性,缩短手术时间、减少术中出血量及放射线的暴露强度。     

经皮植入椎弓根螺钉的CT扫描钉道分析和临床评价

目的：通过应用经皮穿刺植入椎弓根螺钉的后路固定系统治疗胸腰段骨折患者，以探究该微创技术的准确性和可行性。方法：应用菲力浦X线荧屏透视，经皮穿刺植入导针引导的空心椎弓根螺钉136枚，后路固定系统治疗胸腰段骨折34例。术后CT扫描观察钉道与椎弓根内侧壁、外侧壁的关系，钉尖与椎体前缘的距离、TSA角、SSA角，以及进行术后的初步临床疗效观察。结果：其中椎弓根内侧壁破裂4枚，椎弓根外侧壁破裂3枚，经皮椎弓根螺钉方向过于向头端偏斜2枚，过于向尾端偏斜1枚，经皮椎弓根螺钉钉尖稍穿透椎体前缘5枚，本组经皮椎弓根螺钉植钉失误率7．25％。结论：该技术具有一定的准确性和可行性，并发症发生率相对可以接受，但有较高操作要求，需要有经验的脊柱外科医生进行。本组病例在X线荧屏透视下完成，受辐射量大，后来植钉时透视次数明显减少，患者和医师受辐射量下降而且手术时间缩短，如结合导航技术将在微创脊柱外科领域中发挥相当作用。     

Segmental pedicle screw instrumentation in idiopathic thoracolumbar and lumbar scoliosis

The role of posterior correction and fusion in thoracolumbar and lumbar scoliosis as well as pedicle screw instrumentation in scoliosis surgery are matters of debate. Our hypothesis was that in lumbar and thoracolumbar scoliosis, segmental pedicle screw instrumentation is safe and enables a good frontal and sagittal plane correction with a fusion length comparable to anterior instrumentation. In a prospective clinical trial, 12 consecutive patients with idiopathic thoracolumbar or lumbar scolioses of between 40° and 60° Cobb angle underwent segmental pedicle screw instrumentation. Minimum follow-up was 4 years (range 48– 60 months). Fusion length was defined according to the rules for Zielke instrumentation, normally ranging between the end vertebrae of the major curve. Radiometric analysis included coronal and sagittal plane correction. Additionally, the accuracy of pedicle screw placement was measured by use of postoperative computed tomographic scans. Major curve correction averaged 64.6%, with a loss of correction of 3°. The tilt angle was corrected by 67.0%, the compensatory thoracic curve corrected spontaneously according to the flexibility on the preoperative bending films, and led to a satisfactory frontal balance in all cases. Average fusion length was the same as that of the major curve. Pathological thoracolumbar kyphosis was completely corrected in all but one case. One patient required surgical revision with extension of the fusion to the midthoracic spine due to a painful junctional kyphosis. Eighty-five of 104 screws were graded “within the pedicle”, 10 screws had penetrated laterally, 5 screws bilaterally and 4 screws medially. No neurological complications were noted. In conclusion, despite the limited number of patients, this study shows that segmental pedicle screw instrumentation is a safe and effective procedure in the surgical correction of both frontal and sagittal plane deformity in thoracolumbar and lumbar scoliosis of less than 60°, with a short fusion length, comparable to anterior fusion techniques, and minimal loss of correction. Received: 23 September 1999 Revised: 20 January 2000 Accepted: 26 January 2000     

Computer navigation of parapedicular screw fixation in the thoracic spine: a cadaver study.

STUDY DESIGN: An in vitro study to investigate the advantages of computer assistance for the purpose of parapedicular screw fixation in the upper and middle thoracic spine. OBJECTIVES: To evaluate the feasibility and application accuracy of parapedicuar screw insertion with the assistance of an optoelectronic navigation system. SUMMARY OF BACKGROUND DATA: Because of anatomic limitations, thoracic pedicle screw insertion in the upper and middle thoracic spine remains a matter of controversy. The technique of parapedicular screw insertion has been described as an alternative, although the exact screw position is difficult to control. With the assistance of computer navigation for the screw placement, it might become possible to overcome these challenges. METHODS: Four human specimens were harvested for this study; 6-mm screws were inserted from T2 to T8 with the assistance of a CT-based optoelectronic navigation system. During surgery virtual images of the screw position were documented and compared with postoperative contact radiographs to determine the application accuracy. The following measurements were obtained: axial and sagittal screw angles as well as the screw distances to the anterior vertebral cortex and the medial pedicle wall. RESULTS: All 54 screws were inserted in a parapedicular technique without violation of the medial pedicle wall or the anterior or lateral vertebral cortex. The mean +/- standard deviation difference between the virtual images and the radiographs was 1.0 +/- 0.94 mm for the distance to the medial pedicle wall and 1.9 +/- 1.44 mm for the distance to the anterior cortex. The angular measurements showed a difference of 1.6 +/- 1.1 degrees for the transverse screw angle and 2.1 +/- 1.6 degrees for the sagittal screw orientation. CONCLUSION: With the assistance of computer navigation it is possible to achieve a safe and reliable parapedicular screw insertion in the upper and middle thoracic spine in vitro. The application accuracy varies for the linear and angular measurements and is higher in the axial than in the sagittal plane. It is important for the surgeon to understand these limitations when using computer navigation in spinal surgery.     

Biomechanical study of pedicle screw fixation in severely osteoporotic bone.

BACKGROUND CONTEXT: Obtaining adequate purchase with standard pedicle screw techniques remains a challenge in poor quality bone. The development of alternate insertion techniques and screw designs was prompted by recognition of potential fixation complications. An expandable pedicle screw design has been shown to significantly improve fixation compared to a conventional screw in poor quality bone. PURPOSE: The purpose of this study was to determine if polymethylmethacrylate (PMMA) bone cement augmentation of an expandable pedicle screw can further improve fixation strength compared to the expandable screw alone in severely osteoporotic bone. A technique for cement insertion into the pedicle by means of the cannulated central portion of the expandable screw is also described. STUDY DESIGN: The axial pullout strength, stiffness and energy absorbed of cemented and noncemented expandable pedicle screws was determined in cadaveric vertebrae. METHODS: Twenty-one fresh unembalmed vertebrae from the thoracolumbar spine were used. Radiographs and bone mineral density measurements (BMD) were used to characterize bone quality. Paired cemented and noncemented pedicle screw axial pullout strength was determined through mechanical testing. Mechanical pullout strength, stiffness and energy to failure was correlated with BMD. RESULTS: Overall, there was a 250% increase in mean pullout strength with the cemented expandable screw compared with a noncemented expandable screw including a greater than twofold increase in pullout strength in the most severely osteoporotic bone. The mean stiffness and energy absorbed to failure was also significantly increased. A cemented conventional screw achieved a pullout strength similar to the noncemented expandable screw. CONCLUSIONS: PMMA cement augmentation of the expandable pedicle screw may be a viable clinical option for achieving fixation in severely osteoporotic bone.     

伤椎结合邻近椎椎弓根钉内固定治疗单节段胸腰椎骨折

目的探讨伤椎结合邻近椎椎弓根钉内固定治疗单节段轻中度不稳定型胸腰椎骨折的可行性。方法对64例单节段胸腰椎轻中度不稳定型骨折患者按固定方法分为两组:治疗组29例采用伤椎结合邻近椎椎弓根螺钉内固定,对照组35例采用传统短节段椎弓根螺钉内固定,观察两组椎体前缘高度比及伤椎矢状面Cobb角的变化。结果两组手术均成功。患者均获得随访,时间12个月。术后1周及术后12个月两组伤椎前缘高度比、矢状面Cobb角均较术前明显改善(P0.05),两组术后12个月与术后1周比较有丢失,但差异无统计学意义(P0.05);两组之间比较差异均无统计学意义(P0.05)。结论轻中度不稳定型单节段胸腰椎骨折采用伤椎结合邻近椎椎弓根螺钉内固定是一种有效的方法。     

导航辅助脊柱胸腰段椎弓根钉植入的临床应用

目的探讨临床运用计算机影像导航技术引导脊柱胸腰段椎弓根钉植入的准确性。方法2003年5月-2007年5月，29例患者接受116枚计算机影像导航技术引导脊柱胸腰段椎弓根钉植入手术治疗，T10-T1250枚胸椎弓根钉，L1-L3 66枚腰椎弓根钉。术中记录椎弓根钉植入所需时间及C-臂透视工作次数，椎弓根钉植入完成后，即行C-臂正侧位摄片并与导航路径进行比较测量。术后CT进行椎弓根层面扫描，根据椎弓根钉与椎弓根皮质问关系分为四级：A=在椎弓根内；B=突破皮质，〈2mm；C=突破皮质，2-4mm；C=突破皮质，〉4mm。结果术后CT椎弓根位置扫描显示：A级101枚（87．07％）；B级10枚（8．62％）；C级2枚（1．72％）；D级3枚（2．59％）。1枚椎弓根钉植入平均所需时间：2．73±0．64min（1．15～4．02min）。下胸椎9枚（7．75％）胸椎弓根钉突破皮质，上腰椎6枚（5．17％）腰椎弓根钉突破皮质，且临床观察未发现与椎弓根钉突破皮质相关的神经血管等并发症。植入的椎弓根钉C-臂正侧位摄片与导航路径吻合比较，进钉点均差2．6mm（最大3．1mm），角度均差3．3°（最大5．4°）。结论计算机影像导航辅助脊柱胸腰段椎弓根钉植入，提供二维、多平面实时显示，保证了脊柱胸腰段椎弓根钉植入的准确性及安全性，明显减少放射线的暴露强度。     

下颈椎后路螺钉固定的生物力学研究进展

目前,下颈椎后路螺钉固定除侧块螺钉和椎弓根螺钉技术已普遍应用外,经关节螺钉和经椎板螺钉固定技术也逐渐被重视。本文就此介绍下颈椎后路4种螺钉固定方式,并对各自固定技术的生物力学研究现状进行综述。生物力学研究内容包括三维稳定性、抗拔出力、置钉技术和螺钉特点等。侧块螺钉和椎弓根螺钉技术,因其优越的三维稳定性和较强的抗拔出力,已经作为下颈椎不稳的一种有效固定方法。经关节螺钉固定作为一种新的下颈椎后路固定方法,具有广范的手术适应证,并且该技术相对安全、简易,临床上也取得了良好的疗效。经椎板螺钉固定技术临床应用不多,但通过解剖学和生物力学研究证实,该技术可成为临床上可行的补救技术。上述4种下颈椎后路螺钉固定技术,各有其优劣,临床应用也各不相同,通过对这些技术的生物力学研究,将有助于下颈椎后路螺钉内固定技术的发展,更有效的指导临床工作。     

Navigation at the spine

Computer aided and computer navigated operative techniques have been used for the first time in neurosurgery and surgery of the spine. For computer aided surgery of the spine there are currently two different methods: CT-based and C-arm based techniques. The advantage of the CT-based technique is its accuracy especially in difficult anatomical regions like the cervical and upper thoracic spine, and the possibility of preoperative planning. The advantage of C-arm navigation is the broad intraoperative availability with the disadvantage of limited image quality in some regions of the spine eg, the upper thoracic spine. This last disadvantage has been dramatically improved by introducing 3-D C-arm navigation (ISO C 3-D, Siemens, GER). Generally, all methods enhance the precision of pedicle screw insertion. Clinical as well as experimental studies show an exact pedicle screw position using the computer navigated techniques in over 90% of cases. C-arm based navigational techniques are being constantly improved and the future will be CT-like images with instant intraoperative availability.     

The use of evoked EMG in detecting misplaced thoracolumbar pedicle screws.

STUDY DESIGN: Experimental study performed using an animal model. OBJECTIVES: To determine if EMG responses generated by the electrical stimulation of thoracolumbar pedicle screws could be used to predict the screw position. SUMMARY OF BACKGROUND DATA: Evoked EMG has been used successfully to predict pedicle screw position in the lumbar spine. No data have been published on its effectiveness in the thoracic spine. METHODS: A total of 91 screws were inserted into the pedicles from T8 to L2 in six sheep. Monitoring electrodes were placed into transversus abdominus at three levels, the lower two intercostal spaces, and into psoas. A constant voltage stimulus was applied to a probe inserted into each pedicle, and then to each pedicle screw after it had replaced the probe. The threshold voltage required to evoke EMG activity in the relevant myotome was noted. After monitoring the position of each screw was determined by gross dissection. RESULTS: EMG responses in abdominal and intercostal muscles were successfully evoked by thoracic pedicle screw stimulation. Of the 91 screws, 50 were within the pedicle and required an average voltage of 15.12 V to stimulate an EMG response, compared with the 41 misplaced screws that had an average voltage of 7.63 V (P < 0.0001). Using a threshold of 10 V the technique has a sensitivity of 94% and a specificity of 90%. CONCLUSION: Electrical stimulation of pedicle screws and EMG recording in abdominal and leg muscles in sheep provide a reliable indication of pedicle screw position. This technique can be directly applied to human thoracolumbar surgery, but differences in pedicle size would mean that new threshold voltage criteria would need to be established.