三维虚拟图像导航技术在脊柱椎弓根螺钉固定中的应用☆

背景：近年来经椎弓根螺钉固定技术显著提高了脊柱固定强度和融合效率,但是椎弓根螺钉置入位置不佳可能损害脊髓和神经引起严重并发症。 目的：评估置入前CT扫描三维虚拟图像导航技术在脊柱椎弓根螺钉固定中的应用价值。 设计、时间及地点：前瞻性、随机对照观察,于2006-01/2008-12在中国医学科学院北京协和医院骨科完成。 对象：纳入因脊柱疾病行椎弓根螺钉固定的患者95例,导航组45例,常规组50例。 方法：将95例患者按随机数字表法分为2组,导航组术中在计算机导航技术辅助下置入椎弓根螺钉,常规组采用传统的解剖标志法结合术中透视定位置入椎弓根螺钉。 主要观察指标：比较2组间螺钉钉道准备时间、螺钉位置优良率及螺钉置入后并发症的发生率。 结果：导航组中36例患者共置入椎弓根螺钉206枚,优良率96.1%;有9例患者因故未能行导航。常规组50例患者共置入椎弓根螺钉285枚,优良率100.0%,无位置差的螺钉。2组患者的螺钉位置优良率差异无显著性意义(P > 0.05)。导航组的钉道准备时间显著长于常规组[(360±22),(56±8) s,P < 0.01]。2组患者螺钉置入后均无并发症发生。 结论：与传统解剖标志定位法相比,应用置入前CT扫描三维虚拟图像导航技术置入椎弓根螺钉的精度无明显差异,且延长了手术时间,其在脊柱椎弓根螺钉固定中的应用价值有限。     

计算机导航辅助下颅颈交界区畸形的内固定治疗

目的探讨计算机导航在颅颈交界区畸形内固定治疗中的应用价值。方法回顾性分析25例颅颈交界区畸形的病例资料,均在计算机导航辅助下行后路寰枢椎钉棒内固定治疗。术后所有病例随访至少12个月,同时采用日本骨科协会(JOA)脊髓功能评分对病人神经功能进行评估。结果术中导航辅助下行寰椎侧块、枢椎椎弓根螺钉固定15例,经寰枢关节螺钉固定6例,经寰枢关节螺钉联合Brooks技术固定4例;所有病人术中予以植骨融合。末次随访JOA评分由术前的(9.25±2.01)分提高至(14.36±1.97)分,差异具有统计学意义(P0.05)。所有病人螺钉置入位置满意,未发生椎动脉及神经损伤等并发症。结论计算机辅助导航为术者实施颅颈交界区畸形内固定手术提供重要帮助,在提高术中螺钉置入准确性、减少手术损伤、降低手术并发症等方面有巨大潜力。     

O形臂导航辅助经皮椎弓根螺钉内固定的初步应用

目的探讨O形臂导航辅助经皮椎弓根螺钉内固定的准确性与安全性。方法回顾性分析7例经皮椎弓根螺钉内固定病人的临床及影像学资料。病人均在置钉结束后行O形臂系统3D扫描,按照Gertzbein-Robbins分级评估置钉的准确性。结果 7例病人在O形臂导航辅助下共置入29枚椎弓根螺钉,其中Gertzbein-Robbins分级A级23枚(79.31%),B级4枚(13.79%),C级1枚(3.45%),E级1枚(3.45%)。手术共置入29枚克氏针,其中1枚(3.45%)突破椎体前缘。术中无关节突关节受到破坏。1例出现置钉相关神经并发症行再次手术调整椎弓根螺钉。随访(8.29±2.43)个月,无钉棒置入后相关并发症。结论 O形臂导航辅助经皮椎弓根螺钉内固定具有较高的准确性及安全性。     

自发性寰枢关节脱位后路复位内固定术中枢椎椎弓根螺钉置入不能时的备选方法

目的探讨自发性寰枢关节脱位后路内固定过程中枢椎椎弓根螺钉置入不能时,其他备选螺钉内固定技术的安全性及有效性。方法对贵州省人民医院神经外科未采用枢椎椎弓根螺钉内固定治疗的11例自发性寰枢关节脱位患者的临床资料进行回顾性分析。在枢椎椎弓根螺钉置入不能时,采用枢椎椎板螺钉、峡部螺钉、枢椎下关节突螺钉及延长固定节段至C3侧块螺钉来增加稳定性的方法。手术前后分别行CT及MRI检查,评价脊髓受压程度、脱位复位情况、螺钉位置、骨融合情况;通过比较术前、术后日本骨科协会(JOA)评分来评价疗效。结果 11例患者均为枢椎椎弓根置钉不能,改用备选方法置钉,全部行枕颈钉棒内固定。共置入枢椎椎板锣钉14枚,枢椎峡部螺钉5枚,枢椎下关节突螺钉1枚,延长固定节段至C3侧块螺钉4枚。术中均未发生椎动脉和脊髓神经根损伤。11例患者的寰枢关节脱位均得到不同程度的复位,随访中无患者出现螺钉松动、滑脱、断钉及复位丢失等情况,JOA评分为显著增加。结论对自发性寰枢关节脱位后路内固定过程中枢椎椎弓根螺钉置入不能时,可根据情况,个性化选用枢椎椎板螺钉、峡部螺钉、枢椎下关节突螺钉及延长固定节段至C3侧块螺钉的方法来固定,是可行且有效的。     

计算机导航辅助椎弓根螺钉固定的临床研究

目的椎弓根螺钉固定是脊柱病变切除后稳定性重建的标准方法。常规术中透视监测行颈胸节段椎弓根螺钉固定具有相当挑战性,本文旨在就计算机导航辅助椎弓根螺钉固定技术进行初步分析。方法2005年1月至2006年3月在计算机导航系统辅助下,对21例患者（年龄17～63岁,平均43．4岁）共行102枚椎弓根螺钉固定。术前采用0．75mm薄层螺旋CT数据扫描并导入计算机工作站进行脊柱三维重建;术中进行工具注册和匹配后对椎弓根螺钉固定进行实时显示。术后所有病例均采用CT和X线平片随访监测效果。结果手术顺利,螺钉大小选择合适,102枚椎弓根螺钉中100枚螺钉（98%）固定位置及方向准确,2枚椎弓根螺钉突破椎弓根外壁距离小于2mm。所有操作均未发生血管和神经损伤并发症。术中透视次数及手术室人员所受X线辐射量明显减少。结论计算机导航辅助椎弓根螺钉固定是一项安全的手术,且手术精度高。     

颅颈交界区后路螺钉内固定

目的 报告C2椎弓根螺钉结合C1侧块或枕骨螺钉用于颅颈交界区后路内固定的解剖研究及临床应用结果.方法 福尔马林固定的头颈标本4个,根据解剖标志分别植入C2椎弓根及C1侧块螺钉,然后行CT扫描及重建,观察螺钉位置.2004年5月至2007年1月,利用C2椎弓根一C1侧块/枕骨螺钉内同定9例病人,男4例,女5例,年龄12～68岁,平均38岁;各种原因引起的C1～C2半脱位6例,因颅底凹陷经口腔齿状突切除后1例,斜坡脊索瘤经口腔切除手术前2例;采用C2椎弓根-C1侧块螺钉技术4例,C2椎弓根一枕骨螺钉技术5例,手术后均行CT扫描观察螺钉位置.结果 手术中直接显露C2椎弓根内上缘,并以此确立进钉方向,在椎弓根峡部后缘确定进钉点,可保证C2椎弓根螺钉的安全植入;直接显露C1侧块后正中确立进钉点,可避免螺钉植入过程中的椎动脉损伤.9例病人中,手术后CT复查有2例病人两颗螺钉穿破骨皮质,但末造成血管及神经的压迫,其余螺钉位置均较好;随访4-32个月,1例临床症状较术前无变化,其余8例均改善.结论 C2椎弓根-C1侧块/枕骨螺钉技术可安全有效地用于颅颈交界区内固定.     

神经导航在脊柱固定手术中的应用

目的：探讨应用神经导航系统进行椎弓根螺钉植入的优越性及近期疗效。方法在神经导航辅助下,对17例病人植入76枚椎弓根螺钉,记录单个椎体注册时间、钉道准备时间、术中出血量、术中“C”型臂照射次数、导航精度、术中螺钉重植次数及术后并发症;术后行CT检查评价椎弓根螺钉位置。结果平均单个椎体注册时间（6.3±2.1） min,平均钉道准备时间（2.6±1.3） min,平均术中出血量（253±70） ml;平均“C”型臂照射次数（3.5±0.5）;平均导航精度（0.9±0.1） mm。根据Richter法评估螺钉植入位置：优70枚,良5枚,差1枚;优良率98.68%。术中重植螺钉4枚,重植率5.26%。10例病人随访3～7个月,均无明显神经系统阳性体征。结论在神经导航辅助下,术者可以实时监测螺钉植入过程,前瞻性地判断植入椎弓根螺钉的大小、位置,使椎弓根螺钉植入有较高的准确性和安全性。     

术中CT辅助下椎弓根螺钉置入的精确性和安全性评估

目的 评估术中CT辅助下椎弓根固定技术的安全性和准确性。方法 回顾性分析2014年5月至2015年5月术中CT辅助下椎弓根固定手术治疗的39例脊柱脊髓疾病患者的临床资料,其中脊柱脊髓损伤6例,颅颈交界区畸形6例,脊柱退行性变14例,脊柱脊髓肿瘤13例;术后应用Gertzbein-Robbins分级评价螺钉植入的精确性。结果 椎弓根螺钉固定总数为112枚,术中根据CT影像进行位置修正的螺钉共38枚;其中脊柱脊髓损伤23枚,颅颈交界区畸形8枚,脊柱退行性变40枚,脊柱脊髓肿瘤41枚;颈椎 23枚,胸椎48枚,腰椎41枚。根据Gertzbein-Robbins分级0级105枚,1级5枚,2级2枚。术后发生切口感染4例、脑脊液漏2例、神经损伤1例,未发生与螺钉植入直接相关的并发症,也无二次翻修病例。结论 术中CT能够帮助术者在术中发现位置不良的椎弓根螺钉并对其进行修正,提高椎弓根螺钉植入固定术的精确性和安全性。     

无框架脊柱导航手术机器人腰椎弓根标准轴位引导置针

背景：腰椎弓根螺钉内固定具有很好的生物力学效果,是目前脊柱外科常用的技术。各种各样的经椎弓根引导置入方法,包括计算机辅助导航等,均存在一定的失误率,误置会导致严重后果。 目的：采用自主研发的无框架脊柱导航手术机器人,在椎弓根标准轴位透视引导下置入导针,以期为临床探索一种精准度更高、操作更为简便的经椎弓根穿刺或置入方法。 方法：取6具干燥腰椎体标本(L1~L5),置针前用CT扫描并三维重建后,测量椎弓根中心轴线与椎体自身矢状面的夹角α,以及它与椎体上终板前后缘连线所在平面的夹角β。术中C臂机透视确定腰椎骨标准正位像后,依据α与β角度将其向目标侧椎弓根旋转,进行椎弓根标准轴位投照,遥操作机器人,令导针沿椎弓根近圆环状投影的中心置入。置针后摄椎体侧位像、轴位像观察导针的位置,并行CT扫描测量针道α及β角。 结果与结论：60个椎弓根均成功置入导针,置针后椎体X射线侧位像、轴位像及CT扫描横断面图像显示导针位于椎弓根中心,均未见导针接触或穿破椎弓根骨皮质。提示椎弓根标准轴位投照引导下无框架脊柱导航手术机器人置针,是一种精准度高、可靠安全的新方法,操作简便,并能减少或避免射线暴露。     

胸腰椎椎弓根螺钉置入位置不当19例分析☆

目的：分析胸腰椎椎弓根螺钉置入位置不当的原因。 方法：选择2002-01/2008-01南京中医药大学无锡附属医院骨科收治的经影像学证实的胸腰椎椎弓根螺钉置入位置不当患者19例,男12例,女7例;年龄23~68岁,平均52.5岁。其中胸腰椎骨折5例,腰椎滑脱症8例,退行性腰椎疾病6例。椎弓根固定系统：Steffee 4例,DRFS 3例,RF 6例,AF 4例,GSS 2例。所有病例均经X射线正侧位平片及经椎弓根平面CT薄层扫描观察椎弓根螺钉位置,包括螺钉与椎弓根及硬膜囊,周围大血管的解剖位置关系。 结果：患者自螺钉置入后至发现椎弓根螺钉误置时间为5~69 d,平均18.5 d。其中螺钉穿破椎弓根外侧皮质7例,穿破椎弓根内侧皮质4例,螺钉穿破椎弓根皮质(脊柱侧弯伴旋转)2例,螺钉置入过深2例,螺钉进入椎间孔2例,进入椎间隙2例。 结论：螺钉置入不当的原因与对局部解剖变异及操作技术有关,提高手术技巧、术前术中影像学的测量及监控是正确置钉的关键。     

神经外科手术机器人置入椎弓根螺钉的精准性

目的 探讨神经外科手术机器人在人体腰椎模型进行椎弓根螺钉置入的精准性。方法 利用O型臂影像系统对模型进行正侧位扫描，并三维重建，获取3D-CT数据，传入手术机器人系统，规划椎弓根螺钉的最佳进钉点和进钉方向。手术机器人系统利用3D-CT数据自动注册后，置入椎弓根螺钉。应用置钉前后的3D融合图像，按照Gertzbein-Robbins分级评估置钉的准确性。结果 共置入39枚椎弓根螺钉，其中37枚螺钉完全位于椎弓根内，2枚螺钉突破椎弓根的内壁2 mm以内。螺钉与原规划钉道的平均偏移距离为（1.45±0.67）mm。螺钉在进钉点的滑移方向:内下方16枚（41.03%），外上方6枚（15.38%），下方6枚（15.38%），外下方5枚（12.82%），内上方4枚（10.26%），内方1枚（2.56%），上方1枚（2.56%）。结论 神经外科手术机器人置入椎弓根螺钉具有较高的精准性。     

Pedicle Screw Placement in the Thoracolumbar Spine Using a Novel,Simple, Safe,and Effective Guide-Pin : A Computerized Tomography Analysis

ObjectiveTo improve pedicle screw placement accuracy with minimal radiation and low cost, we developed specially designed K-wire with a marker. To evaluate the accuracy of thoracolumbar pedicle screws placed using the novel guide-pin and portable X-rays.MethodsObservational cohort study with computerized tomography (CT) analysis of in vivo and in vitro pedicle screw placement. Postoperative CT scans of 183 titanium pedicle screws (85 lumbar and 98 thoracic from T1 to L5) placed into 2 cadavers and 18 patients were assessed. A specially designed guide-pin with a marker was inserted into the pedicle to identify the correct starting point (2 mm lateral to the center of the pedicle) and aiming point (center of the pedicle isthmus) in posteroanterior and lateral X-rays. After radiographically confirming the exact starting and aiming points desired, a gearshift was inserted into the pedicle from the starting point into the vertebral body through the center of pedicle isthmus.ResultsNinety-nine percent (181/183) of screws were contained within the pedicle (total 183 pedicle screws : 98 thoracic pedicle screws and 85 lumbar screws). Only two of 183 (1.0%) thoracic pedicle screws demonstrated breach (1 lateral in a patient and 1 medial in a cadaver specimen). None of the pedicle breaches were associated with neurologic or other clinical sequelae.ConclusionA simple, specially designed guide-pin with portable X-rays can provide correct starting and aiming points and allows for accurate pedicle screw placement without preoperative CT scan and intraoperative fluoroscopic assistance.     

Robotics in spine surgery: A systematic review

Robotic systems to assist with pedicle screw placement have recently emerged in the field of spine surgery. Here, the authors systematically reviewed the literature for evidence of these robotic systems and their utility. Thirty-four studies that reported the use of spinal instrumentation with robotic assistance and met inclusion criteria were identified. The outcome measures gathered included: pedicle screw accuracy, indications for surgery, rates of conversion to an alternative surgical method, radiation exposure, and learning curve. In our search there were five different robotic systems identified. All studies reported accuracy and the most commonly used accuracy grading scale was the Gertzbein Robbins scale (GRS). Accuracy of clinically acceptable pedicle screws, defined as < 2 mm cortical breech, ranged from 80% to 100%. Many studies categorized indications for robotic surgery with the most common being degenerative entities. Some studies reported rates of conversion from robotic assistance to manual instrumentation due to many reasons, with robotic failure as the most common. Radiation exposure data revealed a majority of studies reported less radiation using robotic systems. Studies looking at a learning curve effect with surgeon use of robotic assistance were not consistent across the literature. Robotic systems for assistance in spine surgery have continued to improve and the accuracy of pedicle screw placement remains superior when compared to free-hand technique, however rates of manual conversion are significant. Currently, these systems are successfully employed in various pathological entities where trained spine surgeons can be safe and accurate regardless of robotic training.     

Application of different thresholds for instrumentation device testing in minimally invasive lumbosacral spine fixation

The main aim of this study was evaluating the reliability of stimulus-evoked electromyography (using different thresholds for stimulation of the instrumentation devices) for minimally invasive pedicle screw placement in the lumbosacral spine. A threshold of 5 mA was applied for the pedicle access needle. 7 mA was applied for the tapscrew and pedicle screw stimulation. The existence of threshold differences between vertebral levels was also assessed. All patients underwent postoperative computed tomography (CT) to determine the accuracy of pedicle screw placement. A total of 172 percutaneous pedicle screws were placed in 52 patients. 94.1% of screws were placed at L4, L5 and S1 vertebral levels. No statistically significant differences existed in thresholds of the pedicle access needles, tapscrews and pedicle screws between vertebral levels. In four instances, the pedicle access needle stimulation had a threshold of 5 mA (no breaches were associated). In the rest of occasions, the pedicle access needles had stimulation thresholds above 5 mA. In all instances, tapscrew and pedicle screw thresholds were above 7 mA; the tapscrews and pedicle screws had significantly greater thresholds than the pedicle access needles. No statistically significant differences existed in thresholds between tapscrews and pedicle screws. Postoperative CT imaging revealed one lateral pedicle violation. Both breach rate and false negative rate were 0.5%. No false positive cases were observed. No patients experienced postoperative pedicle screw–related neurologic deficits. A threshold of 5 mA for the pedicle access needle stimulation seems to be safe. Greater than 7 mA should be used for the tapscrew and pedicle screw stimulation.     

胸椎椎弓根外固定技术的临床应用☆

应用椎弓根外内固定技术2004/2007年在中山大学附属第三医院骨科治疗34例患者，固定前采用CT加密扫描测量进钉点、进钉点至椎体前缘的深度、进钉角度和直径，固定中椎弓根钉入点为横突尖，进钉方向为平均向头侧倾斜10°~ 20°、与中线成角30°~40°，顺椎弓根外侧皮质进入椎体，固定后CT加密扫描观察螺钉周围的皮质骨是否完整、是否靠近节段血管、是否穿透皮质骨，评价置入钉的准确性和安全性。34例患者共置入160枚胸椎椎弓根螺钉,固定后CT加密扫描和X射线片观察到148枚(92.5% )螺钉置入准确，12枚(7.5%)螺钉发生错置。实验结果表明，胸椎椎弓根根外内固定与椎弓根内固定相比，具有更宽的置入宽度，更长的螺钉长度，以及更大的内聚角度，具有安全可靠、简单实用等优点，并具有生物力学优越性，是胸椎后路内固定的一种良好选择。     

The Clinical Experience of Computed Tomographic-Guided Navigation System in C1-2 Spine Instrumentation Surgery

Objective

To identify the accuracy and efficiency of the computed tomographic (CT)-based navigation system on upper cervical instrumentation, particularly C1 lateral mass and C2 pedicle screw fixation compared to previous reports.

Methods

Between May 2005 and March 2014, 25 patients underwent upper cervical instrumentation via a CT-based navigation system. Seven patients were excluded, while 18 patients were involved. There were 13 males and five females; resulting in four degenerative cervical diseases and 14 trauma cases. A CT-based navigation system and lateral fluoroscopy were used during the screw instrumentation procedure. Among the 58 screws inserted as C1-2 screws fixation, their precise positions were evaluated by postoperative CT scans and classified into three categories : in-pedicle, non-critical breach, and critical breach.

Results

Postoperatively, the precise positions of the C1-2 screws fixation were 81.1% (47/58), and 8.6% (5/58) were of non-critical breach, while 10.3% (6/58) were of critical breach. Most (5/6, 83.3%) of the critical breaches and all of non-critical breaches were observed in the C2 pedicle screws and there was only one case of a critical breach among the C1 lateral mass screws. There were three complications (two vertebral artery occlusions and a deep wound infection), but no postoperative instrument-related neurological deteriorations were seen, even in the critical breach cases.

Conclusion

Although CT-based navigation systems can result in a more precise procedure, there are still some problems at the upper cervical spine levels, where the anatomy is highly variable. Even though there were no catastrophic complications, more experience are needed for safer procedure.     

Evaluation of the implantation of transpedicular screws in spinal instrumentation with free-hand technique and navigation-assisted with intraoperative computed tomography: An analytical-positional study

BackgroundSpinal instrumentation using transpedicular screws has been used for decades to stabilize the spine. In October 2018, an intraoperative CT system was acquired in the Neurosurgery service of the University Hospital Complex of Vigo, this being the first model of these characteristics in the Spanish Public Health System, so we began a study from January 2015 to December 2019 to assess the precision of the transpedicular screws implanted with this system compared with a control group performed with the classical technique and final fluoroscopic control.MethodsThe study was carried out in patients who required transpedicular instrumentation surgery, in total 655 screws were placed, 339 using the free-hand technique (Group A) and 316 assisted with intraoperative CT navigation (Group B) (p > 0.05). Demographic characteristics, related to surgery and the screw implantation grades were assessed using the Gertzbein–Robbins classification.Results92 patients were evaluated, between 12 and 86 years (average: 57.1 years). 161 thoracic screws (24.6%) and 494 lumbo-sacral screws (75.4%) were implanted. Of the thoracic screws, 33 produced a pedicle rupture. For the lumbo-sacral screws, 71 have had pedicle violation. The overall correct positioning rate for the free-hand group was 72.6% and for the CT group it was 96.5% (p < 0.05).ConclusionThe accuracy rate is higher in thoracic-lumbar instrumentation in the navigation group versus free-hand group with fluoroscopic control.