颈椎椎弓根钉内固定研制及置钉准确性研究

目的:设计一种具有纵向撑开和压缩功能的颈椎椎弓根钉内固定,并行颈椎椎弓根钉置钉训练,研究其进钉准确性。方法:(1)收集颈椎新鲜标本7具,先采用CT扫描椎弓根,测量椎弓根内外径的高度和宽度;(2)设计合适的椎弓根钉内固定系统;(3)在收集的7具颈椎新鲜标本70个椎弓根上行置钉操作训练,评价其置钉准确性。结果:颈椎椎弓根直径一般>4.5mm,其高度大于宽度,可适于椎弓根钉内固定使用,颈椎椎弓根钉置钉的准确性高。但颈椎椎弓根存在个体差异,宜行个体化进钉。结论:颈椎椎弓根解剖学上可以满足椎弓根钉内固定的使用。     

颈椎椎弓根钉内固定研制及置钉准确性研究

目的设计一种具有纵向撑开和压缩功能的颈椎椎弓根钉内固定,并行颈椎椎弓根钉置钉训练,研究其进钉准确性.方法(1)收集颈椎新鲜标本7具,先采用CT扫描椎弓根,测量椎弓根内外径的高度和宽度;(2)设计合适的椎弓根钉内固定系统;(3)在收集的7具颈椎新鲜标本70个椎弓根上行置钉操作训练,评价其置钉准确性.结果颈椎椎弓根直径一般>4.5mm,其高度大于宽度,可适于椎弓根钉内固定使用,颈椎椎弓根钉置钉的准确性高.但颈椎椎弓根存在个体差异,宜行个体化进钉.结论颈椎椎弓根解剖学上可以满足椎弓根钉内固定的使用.     

三维CT导航辅助胸椎椎弓根螺钉的植入

目的探讨三维CT导航在胸椎椎弓根螺钉植入手术中的应用价值。方法24例行CT导航下椎弓根螺钉固定术，其中胸椎骨折14例，胸椎肿瘤6例，脊柱侧弯4例。向导航系统输入CT资料，选择配准方式为点匹配法，配准成功后，用导航棒预先设置螺钉的最佳位置、直径和长度，按导航计划立体、动态地植入螺钉，术后进行CT扫描，按Rampersaud分类法评估螺钉的位置。结果导航下成功对24例共植入144枚椎弓根螺钉。按Rampersaud分类法：A级136枚（94．4％），B级6枚，C级1枚，D级1枚。术后无神经、脊髓损伤。22例平均随访8个月（6～14个月），复查X线片和CT，无螺钉松动和断裂钉，无迟发性脊髓损伤。结论三维CT导航系统可以准确引导胸椎椎弓根螺钉的植入。     

Automated Intraoperative EMG Testing During Percutaneous Pedicle Screw Placement

BACKGROUND: EMG screw testing has been shown to be sensitive and reliable in open spinal instrumentation cases. However, there is little evidence to show its applicability to percutaneous screw placement. PURPOSE: To demonstrate the utility of EMG testing in percutaneous techniques, where lack of direct visualization poses an added risk to nerve injury. STUDY DESIGN: Summary of intraoperative EMG results during percutaneous pedicle screw placement. METHODS: Percutaneous pedicle screws were placed in twenty patients (22 levels, 88 pedicles). The initial fluoroscopically-guided k-wires and the subsequent taps were insulated and stimulated via an automated EMG system. Low threshold values prompted repositioning of the pedicle trajectory. RESULTS: Four (5%) k-wires induced EMG thresholds less than 10mA, prompting repositioning. One was repositioned without improvement, but with improvement upon tapping. One k-wire with very low threshold (3mA) was repositioned with an improved result (13mA). In 78 pedicles (89%) the tap threshold was greater than the k-wire. CONCLUSIONS: EMG testing helps to identify suboptimal screw trajectories, allowing for early adjustment and confirmation of improved placement. Tapping often improved thresholds, perhaps by compressing the bone and creating a denser, more insulative pedicle wall. EMG testing may improve the safety of percutaneous screw techniques, where the pedicle cannot be visually inspected.     

Analysis of CT-based Navigation System for Pedicle Screw Placement

The incidence of pedicle screw breech varies based on anatomic location, body habitus, surgeon experience, spinal deformity, and surgical technique. Pedicle breeches have been reported to occur in up to 40% of screws. The purpose of this retrospective study was to compare the rates of revision of pedicle screw placement when using intraoperative C-arm vs O-arm (Medtronic, Memphis, Tennessee) assessment of pedicle screws. An economic analysis was also performed based on the estimated cost of pedicle screw revision.Four (1%) of 386 control patients required pedicle screw revision for a breeched pedicle screw not identified with intraoperative C-arm fluoroscopy. In the study group, none of the 331 patients returned to the operating room when O-arm was used to assess pedicle screw placement. Based on the 1% rate of returning to the operating room in the control group, the annual rate of cases nationwide requiring pedicle screw revision would be approximately 2300, with a cost of approximately $40,595,000.These results suggest that the use of intraoperative O-arm can reduce the need for revision of a breeched pedicle screw. This can potentially lead to a major cost savings.     

椎弓根螺钉式置钉法在骨盆骨折中的应用

目的：比较椎弓根螺钉式置钉法与常规钻孔置钉法治疗骨盆骨折的效果。方法2005年2月～2013年1月,急诊行外固定架固定骨盆骨折合并休克28例,骨盆骨折AO/OTA分型：B1型1例,B2型6例,B3型8例,C1型8例,C2型4例,C3型1例。每侧髂骨置钉2枚,左侧用电钻钻孔法置钉（对照组）,右侧用椎弓根螺钉式置钉法（观察组）。对比2组手术时间、钉道的准确性、术后螺钉松动、感染发生率。结果术后死亡2例,26例随访2个月～6年。与左侧对照组比较,右侧观察组手术时间短[（4．8±2．1） min vs．（11．2±2．8） min, t＝-8．834, P＝0．000],孔深3 cm、5 cm时钉道穿透少[1．8％（1/56） vs．19．6％（11/56）,χ2＝9．333, P＝0．002;10．7％（6/56） vs．33．9％（19/56）,χ2＝8．703, P＝0．003],术后钉周感染少[9．6％（5/52） vs．30．8％（16/52）,χ2＝7．220, P＝0．007],2组螺钉松动发生率差异无显著性（P＞0．05）。结论椎弓根螺钉式置钉法具有手术时间短、准确性高、术后并发症少的优点。     

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.     

寰椎椎弓根螺钉置钉的解剖与临床研究

目的：建立和验证寰椎后路椎弓根螺钉固定的进钉技术。方法：利用40套干燥配套寰枢椎标本测量进钉技术的相关参数，而后临床应用该技术方法置钉并行X线、CT复查其准确性。结果：寰椎椎弓根平均宽度为7．78mm，进钉点在寰椎椎弓根中线外侧2．2m，螺钉进钉点可由经枢椎下关节突中点的纵垂线来确定；手术中该方法不仅能简化操作过程，而且术后检查发现螺钉均准确置入。结论：用枢椎下关节突中点作为术中判定寰椎椎弓根螺钉进钉点的方法准确可靠。     

颈椎椎弓根螺钉个体化置钉技术的研究

目的 颈椎椎弓根螺钉的个体化置钉的研究.方法 进行128枚椎弓根螺钉的置入,采用椎弓根螺钉的体化置入技术.手术前对患者颈椎的正侧位x线片进行研究,通过椎弓根纵轴在颈椎侧位像上的投射,确定椎弓根螺钉进钉点的横向进钉线(X线),通过对CT的研究,确定椎弓根纵轴在颈椎侧块上投射的点位,确定椎弓根螺钉进钉点的纵向定位线(Y线),在手术中通过两线的交点确定椎弓根螺钉的进钉点(O点),通过术前的X线确定椎弓根螺钉的头倾角和尾倾角,通过CT确定椎弓根螺钉的内倾角,最终确定椎弓根螺钉的进钉方向,结合手术中一定的操作技术,完成椎弓根螺钉的个体化置钉.结果 本组正确置入118枚,螺钉穿透椎弓根但基本在椎弓根内的6枚,4枚穿出经调整后准确置入.结论 颈椎椎弓根置钉应个体化.     

颈椎椎弓根螺钉徒手植入技术的临床研究

目的 评价颈椎椎弓根螺钉徒手植入技术（无须术中影像技术引导）的安全性和可靠性。方法应用Axis内固定系统（美国枢法模公司）对36例颈椎疾病患者进行颈后路经椎弓根内固定术,共植入螺钉144枚,方法如下：①术中清晰地显露颈椎侧块和突间关节,用直径3,0mm高速球形磨钻去除侧块外上象限处骨皮质,然后用2．0mm的自制手锥沿椎弓根事先确定的方向轻轻钻入,若遇阻力则需略改变方向,使其自然置入,深约2～2,5cm。确定无误后,则安置Axis钛板和置入长度合适的椎弓根螺钉。②安装完毕后,即用C型臂X线机作双斜位透视,无误后关闭切口。结果从G～G,共植入根弓根螺钉144枚,其中10枚（6．8％）钉初次置入后感觉松动,经校正后二次置入成功,11枚（3．5％）钉道钻孔后出血较多,但及时处理后出血停止并无不良结果。术后X线斜位片及CT片显示,16枚（11．1％）螺钉穿破椎弓根,其中10枚螺钉（6．9％）穿破椎弓根外侧皮质,4枚（2．8％）穿破椎弓根上侧皮质,2枚（1．3％）穿破椎弓根下侧皮质。随访未发现与螺钉置入穿破椎弓根皮质有关的神经血管损伤问题。结论本研究提示,在事先充分的对每个患者颈椎椎弓根X线及CT解剖结构了解的情况下,徒手置入椎弓根螺钉行颈椎后路内固定安全可行。     

计算机辅助导航系统引导下的椎弓根螺钉置入术

目的探讨计算机辅助导航系统在椎弓根螺钉置入手术方面的应用价值。方法2002年8月~2006年6月,采用计算机辅助导航系统引导下进行椎弓根螺钉置入手术66例,与传统手术66例进行比较。结果导航组手术时间[(142.3±5.3)minvs(173.4±7.1)min,t=-28.301,P=0.000]和术中出血量[(798.3±10.9)mlvs(912.2±14.3)ml,t=-51.463,P=0.000]显著少于传统手术组。导航组椎弓根螺钉X线片和CT扫描准确性显著高于传统组(χ2=29.424,P=0.000;χ2=36.829,P=0.000)。结论计算机辅助导航系统引导下进行椎弓根螺钉置入手术较传统手术方法具有更加精确、安全、微创的特点。     

Guideline for Thoracolumbar Pedicle Screw Placement Assisted by Orthopaedic Surgical Robot

The pedicle screw placement procedure is the most commonly used technique for spinal fixation and can provide reliable three‐column stabilization. Accurate screw placement is necessary in clinical practice. To avoid screw malposition, which may decrease the stiffness of the screw‐rod construct or increase the likelihood of neural and vascular injuries, the surgeons must fully understand the regional anatomy. Deformities, such as scoliosis, kyphosis or congenital anomalies, may complicate the application of the pedicle screw placement technique and increase the chance of screw encroachments. Incidences of pedicle screw malposition vary in different districts and hospitals and with surgeons and techniques. Today, the minimally invasive spinal surgery is well developed. However, the narrow corridors and limited views for surgeons increase the difficulty of pedicle screw placement and the possibility of screw encroachment. Evidenced by previous studies, robotic surgery can provide accurate screw placement, especially in settings of spinal deformities, anatomical anomalies, and minimally invasive procedures. Based on the consensus of consultant specialists, the literature review and our local experiences, this guideline introduces the robotic system and describes the workflow of robot‐assisted procedures and the precautions to take during procedures. This guideline aims to outline a standardized method for robotic surgery for thoracolumbar pedicle screw placement.     

Isthmus‐guided Cortical Bone Trajectory for Pedicle Screw Insertion

Herein is described cortical bone trajectory (CBT), a new path for pedicle screw insertion for lumbar vertebral fusion. Because the points of insertion are under the end of the inferior articular process, and because the screws are inserted toward the lateral side, there is less soft tissue development than with the conventional technique; the CBT technique therefore enables less invasive surgery than the conventional technique. However, it has some drawbacks. For example, in the original CBT approach, the points of insertion are in the vicinity of the end of the inferior articular process. Because this joint has been destroyed in many patients who have indications for intervertebral fusion surgery, it is sometimes difficult to use it as a reference point for screw insertion location. With severe lateral slippage, the screw insertion site can become significantly dislocated sideways, with possible resultant damaging to the spinal canal and/or nerve root. The CBT technique here involved inserting the screws while keeping clear of the intervertebral foramen with the assistance of side view X‐ray fluoroscopy and using the end of the inferior articular process and the isthmus as points of reference for screw location.     

Detection of Common Anatomical Landmarks and Vertical Trajectories for Freehand Pedicle Screw Placement

Objective

It is clinically important for pedicle screws to be placed quickly and accurately. Misplacement of pedicle screws results in various complications. However, the incidence of complications varies greatly due to the different professional titles of physicians and surgical experience. Therefore, physicians must minimize pedicle screw dislocation. This study aims to compare the three nail placement methods in this study, and explore which method is the best for determining the anatomical landmarks and vertical trajectories.

Methods

This study involved 70 patients with moderate idiopathic scoliosis who had undergone deformity correction surgery between 2018 and 2021. Two spine surgeons used three techniques (preoperative computed tomography scan [CTS], visual inspection-X-freehand [XFH], and intraoperative detection [ID] of anatomical landmarks) to locate pedicle screws. The techniques used include visual inspection for 287 screws in 21 patients, preoperative planning for 346 screws in 26 patients, and intraoperative probing for 309 screws in 23 patients. Observers assessed screw conditions based on intraoperative CT scans (Grade A, B, C, D).

Results

There were no significant differences between the three groups in terms of age, sex, and degree of deformity. We found that 68.64% of screws in the XFH group, 67.63% in the CTS group, and 77.99% in the ID group were placed within the pedicle margins (grade A). On the other hand, 6.27% of screws in the XFH group, 4.33% in the CTS group, and 6.15% in the ID group were considered misplaced (grades C and D). The results show that the total amount of upper thoracic pedicle screws was fewer, meanwhile their placement accuracy was lower. The three methods used in this study had similar accuracy in intermediate physicians (P > 0.05). Compared with intermediate physicians, the placement accuracy of three techniques in senior physicians was higher. The intraoperative detection group was better than the other two groups in the good rate and accuracy of nail placement (P < 0.05).

Conclusion

Intraoperative common anatomical landmarks and vertical trajectories were beneficial to patients with moderate idiopathic scoliosis undergoing surgery. It is an optimal method for clinical application.