Pedicle screw placement in the thoracic spine: a randomized comparison study of computer-assisted navigation and conventional techniques

Objective： To evaluate the accuracy of computer-assisted pedicle screw installation and its clinical benefit as compared with conventional pedicle screw installation techniques.
Methods： Total 176 thoracic pedicle screws placed in 42 thoracic fracture patients were involved in the study randomly, 20 patients under conventional fluoroscopic control （84 screws） and 22 patients had screw insertion under three dimensional （3D） computer-assisted navigation （92 screws）. The 2 groups were compared for accuracy of screw placement, time for screw insertion by postoperative thincut CT scans and statistical analysis by χ^2 test. The cortical perforations were then graded by 2-mm increments： Grade Ⅰ （good, no cortical perforation）, Grade Ⅱ （screw outside the pedicle 〈2 mm）, Grade Ⅲ （screw outside the pedicle 〉2 mm）.
Results： In computer assisted group, 88 （95.65%） were Grade Ⅰ （good）, 4 （4.35%） were Grade Ⅱ （〈2mm）, no Grade Ⅲ （〉2 mm） violations. In conventional group, there were 14 cortical violations （16.67%）, 70 （83.33%） were Grade Ⅰ （good）, Ⅱ （13.1%） were Grade Ⅱ （〈2 mm）, and 3 （3,57%） were Grade Ⅲ （〉2 mm） violations （P〈0.001）. The number （19.57%） of upper thoracic pedicle screws （ T1-T4 ） inserted under 3D computer-assisted navigation was significantly higher than that （3.57%） by conventional fluoroscopic control （P〈0.001）. Average screw insertion time in conventional group was （4.56 ±1.03） min and （2.54 ± 0.63） min in computer assisted group （P〈0.001）. In the conventional group, one patient had pleura injury and one had a minor dura violation.
Conclusions： This study provides further evidence that 3D computer-assisted navigation placement ofpedicle screws can increase accuracy, reduce surgical time, and be performed safely and effectively at all levels of the thoracic spine, particularly upper thoracic spine.     

O-arm计算机导航辅助脊柱椎弓根螺钉置入的准确性

[目的]分析O-arm计算机辅助导航技术在脊柱椎弓根螺钉置入的准确性。[方法]回顾性分析2017年1月~2018年9月本院椎弓根螺钉置入患者575例,根据椎弓根螺钉置入方式不同,分为两组。导航组采用O-arm计算机辅助导航技术系统置入椎弓根螺钉233例,传统组采用传统徒手法置入椎弓根螺钉342例。行CT检查,依据Neo分型评估置钉准确性。[结果]导航组共置入1459枚椎弓根螺钉,其中C1~7置入222枚,T1~12置入535枚,L1~5置入652枚,S1置入50枚。每名患者置钉数量1~24枚,平均(6.26±3.77)枚。传统组共置入1724枚椎弓根螺钉,其中C1~7置入269枚,T1~12置入601枚,L1~5置入785枚,S1置入87枚。每名患者置钉数量1~20枚,平均(5.67±4.11)枚。导航组全部病例顺利完成手术,术中无血管、神经损伤等并发症,置钉安全率为100%,传统组有4例发生血管、神经损伤等并发症。所有患者术后进行12~24个月随访,随访过程均未发生不良事件。依据CT影像Neo分级标准,导航0型及1型椎弓根螺钉的成功置入率达98.01%,而传统组0型及1型椎弓根螺钉的成功置入率91.85%;两组间置入螺钉准确性的差异具有统计学意义(P<0.05)。[结论]与传统C臂X线机等徒手置钉方式相比,O-arm计算机辅助导航技术可提高脊柱椎弓根螺钉置入准确性,同时降低神经、血管等并发症的发生。     

导航下脊柱椎弓根钉置入与传统置入术临床疗效的Meta分析

目的:通过检索和分析国内外相关文献,评价导航辅助下椎弓根钉内固定术与传统通过解剖标志定位的内固定术的置钉位置优良率和临床疗效。方法:计算机检索1990年1月至2012年2月,Pubmed、Medline、OVID和万方医学网等中英文数据库并结合手工检索,按照既定的纳入和排除标准查找有关导航下脊柱椎弓根钉置入术与传统手术置钉术比较的临床随机对照试验(RCT)和前瞻性病例对照试验,对纳入的研究进行质量评价,使用RevMan5.1软件对数据进行Meta分析。结果:共纳入10篇文献,置入2813枚椎弓根钉,其中1561枚在导航辅助下置入,1252枚通过传统方式置入。研究结果提示导航辅助下置入椎弓根钉的优良率[OR=2.58,95%CI(1.18,5.63)]、平均置入时间[WMD=-2.15,95%CI(-2.36,-1.94)]与传统置入方式相比差异有统计学意义,且纳入研究未报道导航下置钉神经损伤相关并发症发生,仅一项研究报道导航辅助下钉道准备时间长于传统手术。结论:导航作为脊柱外科手术的一种辅助手段,可以提高置钉的优良率,加快置入的速度,减少置钉相关并发症,但由于该系统的复杂性可能导致钉道准备时间延长,尚需开展进一步的RCT研究加以验证。     

Genauigkeit der CT-basierten Navigation von Pedikelschrauben an der Brustwirbelsäule im Vergleich zur konventionellen Technik

The goal of this study was to evaluate the accuracy of CT-based computer-assisted pedicle screw insertion in the thoracic spine in patients with fractures, metastases, and spondylodiscitis compared to a conventional technique. A total of 324 pedicle screws were inserted in the thoracic spines of 85 patients: 211 screws were placed using a CT-based optoelectronic navigation system assisted by an image intensifier and 113 screws were placed with a conventional technique. Screw positions were evaluated with postoperative CT scans by an independent radiologist. In the computer-assisted group, 174 (82.5%) screws were found completely within their pedicles compared with 77 (68.1%) correctly placed screws in the conventional group ( p<0.003). Despite use of the navigation system, 1.9% of the computer-assisted screws perforated the pedicle wall by more than 4 mm. The additional use of the image intensifier helped to identify the correct vertebral body and avoided cranial or caudal pedicle wall perforations.     

Accuracy of fluoroscopic navigation of pedicle screws. CT-based evaluation of bone screw placement

While the advantages of C-arm navigation in computer-assisted spine surgery are obvious, the accuracy of pedicle screw placement with virtual fluoroscopy still needs to be verified. The C-arm-based ION system (Medtronic Sofamor Danek) was used to navigate pedicle screw insertion in patients undergoing spinal surgery for various conditions. In a prospective study, a total of 160 screws were inserted in the first 30 consecutive patients since introduction of the system at our institution: 54 at the thoracic spine (highest level: TH4) and 106 at the lumbar spine. Computed tomography (CT) scans were performed postoperatively by two independent radiologists to control the accuracy of screw placement at the level of the pedicles after reconstruction of axial images according to Laine et al. The comparison of the calculated accuracy rate of pedicle screw placement using virtual fluoroscopy with reported results achieved with CT-based navigation shows similar results for virtual fluoroscopy and a remarkable increase of accuracy in comparison to reports on conventional pedicle screw placement.     

Pedicle screw insertion accuracy with different assisted methods: a systematic review and meta-analysis of comparative studies

Studies revealed that navigation systems that provided intraoperative assistance might improve pedicle screw insertion accuracy, and also implied that different systems provided different pedicle screw insertion accuracy. A systematic review and meta-analysis was conducted to focus on the pedicle screw insertion accuracy with or without the assistance of image-guided system, and the variance among the different navigation systems. Comparative studies were searched on pedicle screw insertion accuracy between conventional and navigated method, and among different navigation systems. A total of 43 papers, including 28 clinical, 14 cadaveric and 1 model studies, were included in the current study. For clinical articles, there were 3 randomized clinical trials, 4 prospective comparative studies and 21 retrospective comparative studies. The incidence of pedicle violation among computer tomography-based navigation method group was statistically significantly less than that observed among the conventional group (OR 95% CI, in vivo: 0.32–0.60; in vitro: 0.24–0.75 P < 0.01). Two-dimensional fluoroscopy-based navigation system (OR 95% CI, in vivo: 0.27–0.48; in vitro: 0.43–0.88 P < 0.01) and three-dimension fluoroscopy-based navigation system (OR 95% CI, in vivo: 0.09–0.38; in vitro: 0.09–0.36 P < 0.01) also obtained significant reduced screw deviation rate over traditional methods. Between navigated approaches, statistically insignificant individual and pooled RR values were observed for all in vivo subgroups. Pooled estimate of in vitro studies show that computer tomography-based and three-dimension fluoroscopy-based navigation system provided more accurate pedicle screw insertion over two-dimension fluoroscopy-based navigation system. Our review showed that navigation provided a higher accuracy in the placement of pedicle screws compared with conventional methods. The superiority of navigation systems was obvious when they were applied to abnormal spinal structure. Although no strong in vivo evidence has detected significantly different pedicle screw placement accuracy among the three major navigation systems, meta-analysis revealed the variance in pedicle screw insertion accuracy with different navigation methods.     

双平面骨科机器人系统辅助股骨颈骨折内固定的实验研究

目的 通过股骨近端模型骨的模拟手术,与传统方法徒手操作的临床病例进行对比,评价改进后的双平面骨科机器人系统辅助股骨颈骨折空心钉导针置入位置的准确性以及螺钉的平行性. 方法使用双平面骨科机器人系统对12根股骨近端模型骨进行辅助股骨颈空心钉置入的模拟手术,每例置入3枚导针,通过股骨颈截面的直接测量来评价机器人系统辅助操作的准确性;通过正、侧位X线片角度的测量和计算来评价机器人系统辅助下空心钉之间的平行性,与传统方法徒手操作的临床病例测算结果比较;同时比较两种操作方法所需的透视次数. 结果所有导针均一次成功置入,标本截面测量导针实际位置与规划位置相比误差范围在1 mm左右;对平行度参数的统计学分析结果显示正、侧位X线片上机器人辅助操作的螺钉平行度均优于徒手操作(P<0.05),稳定性也优于徒手操作(P<0.05);在透视次数上,机器人辅助操作组明显少于徒手操作组. 结论改进后的双平面骨科机器人系统可以有效地辅助完成股骨颈骨折空心钉内固定,导针位置的准确性能满足临床应用的需求.空心钉之间的平行性和操作的稳定性均明显优于传统的徒手操作,同时可以大大减少医患的放射线暴露时间.     

Inserting pedicle screws in the upper thoracic spine without the use of fluoroscopy or image guidance. Is it safe?

Several studies have looked at accuracy of thoracic pedicle screw placement using fluoroscopy, image guidance, and anatomical landmarks. To our knowledge the upper thoracic spine (T1–T6) has not been specifically studied in the context of screw insertion and placement accuracy without the use of either image guidance or fluoroscopy. Our objective was to study the accuracy of upper thoracic screw placement without the use of fluoroscopy or image guidance, and report on implant related complications. A single surgeon inserted 60 screws in 13 consecutive non-scoliotic spine patients. These were the first 60 screws placed in the high thoracic spine in our institution. The most common diagnosis in our patient population was trauma. All screws were inserted using a modified Roy-Camille technique. Post-operative axial computed tomography (CT) images were obtained for each patient and analyzed by an independent senior radiologist for placement accuracy. Implant related complications were prospectively noted. No pedicle screw misplacement was found in 61.5% of the patients. In the remaining 38.5% of patients some misplacements were noted. Fifty-three screws out of the total 60 implanted were placed correctly within all the pedicle margins. The overall pedicle screw placement accuracy was 88.3% using our modified Roy-Camille technique. Five medial and two lateral violations were noted in the seven misplaced screws. One of the seven misplaced screws was considered to be questionable in terms of pedicle perforation. No implant related complications were noted. We found that inserting pedicle screws in the upper thoracic spine based solely on anatomical landmarks was safe with an accuracy comparable to that of published studies using image-guided navigation at the thoracic level.     

Navigation Using Fluoro-CT Technology

Abstract Background: The mobile SIREMOBIL^® Iso-C^3D C-arm is a device that permits the intraoperative three-dimensional (3-D) representation of bony structures (multiplanar reconstructions). Linking to navigation makes it possible to transfer the generated 3-D data directly to the navigation system. The advantages of CT-based navigation with 3-D representation of bone structures are therefore combined with the advantages of inherent navigation with intraoperative imaging. The surgical instrument is immediately displayed in the image, i.e., without any complex manual registration procedure. Patients and Methods: Inherent navigation in 3-D images from the Iso-C^3D was successfully used for the first time in this study in a larger group of patients. 39 patients who intraoperatively underwent successful navigation in Iso-C^3D images were included in the study. Results: 143 drilling procedures were performed in the 39 patients. Pedicle instrumentations took place in 24 of the 39 patients. Eight patients underwent screw placements on the pelvic ring (sacroiliac joint screw placement, placement of anterior column screw, acetabulum osteosynthesis). Four patients underwent retrograde perforation of a talus cyst and filling with autologous cancellous bone, while one patient underwent screw osteosynthesis on the neck of the femur, and two patients underwent placement of an external fixator with a hinge at the elbow joint. One pedicle screw was found to be 2 mm out of position in the spinal group. All other screws/drillings were placed correctly. Additionally, in three patients intraoperative navigation had to be aborted due to hard- or software problems. In these cases, surgery was finished in conventional ways. Conclusion: The results herein for the extremities, spine, and pelvis are very encouraging and portend an advance in safety and quality in the operating room (OR). As compared to the conventional approach and other computer-assisted procedures (CT-based navigation, C-arm-based 2-D navigation), the lowest rate of incorrect placements and the lowest average fluoroscopy time were achieved during the placement of pedicle screws on the spine with Iso-C^3D navigation at a comparable average OR duration. Iso-C^3D navigation supports standardized work procedures in the OR.     

计算机导航辅助椎弓根螺钉固定

目的将计算机导航技术应用于临床椎弓根螺钉固定并做仞步分析。方法2004年2～12月在计算机导航系统辅助下，对30例患(年龄18～60岁，平均45．3岁)共行134枚椎弓根螺钉固定。结果手术顺利，未发生血管和神经损伤并发症，螺钉大小选择合适，固定位置及方向准确．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。     

Analysis of accuracy of computer‐assisted navigation in cervical pedicle screw installation

Objective: To observe the accuracy of computer‐assisted navigation (CAN) in cervical pedicle screw installation and to analyze the reasons for screw malposition. Methods: From October 2004 to December 2009, 144 cervical pedicle screws were installed in 25 patients with cervical spinal diseases using CAN. Screw position and direction were measured on sagittal and transection images from intraoperative navigation and postoperative CTs. Results: Among 144 screws inserted from C3 to C7, two perforated the upper pedicle wall and three deviated from the lateral pedicle wall. The rate of accurate cervical pedicle screw placement with CAN was 96.5% (139/144) in our group. There was no statistical difference in the position and direction of the pedicle screws according to navigation images and CT scans. Conclusion: CAN can result in high accuracy of cervical pedicle installation. The excursion phenomenon is responsible for malposition of pedicle screws. Only by understanding the navigational principles of CAN and the characteristics of cervical spinal surgery, together with personal experience, can good use be made of CAN.     

Pedicle screw insertion: robotic assistance versus conventional C-arm fluoroscopy

Bone-mounted robotic guidance for pedicle screw placement has been recently introduced, aiming at increasing accuracy. The aim of this prospective study was to compare this novel approach with the conventional fluoroscopy assisted freehand technique (not the two- or three-dimensional fluoroscopy-based navigation). Two groups were compared: 11 patients, constituting the robotical group, were instrumented with 64 pedicle screws; 23 other patients, constituting the fluoroscopic group, were also instrumented with 64 pedicle screws. Screw position was assessed by two independent observers on postoperative CT-scans using the Rampersaud A to D classification. No neurological complications were noted. Grade A (totally within pedicle margins) accounted for 79% of the screws in the robotically assisted and for 83% of the screws in the fluoroscopic group respectively (p = 0.8). Grade C and D screws, considered as misplacements, accounted for 4.7% of all robotically inserted screws and 7.8% of the fluoroscopically inserted screws (p = 0.71). The current study did not allow to state that robotically assisted screw placement supersedes the conventional fluoroscopy assisted technique, although the literature is more optimistic about the former.     

Accuracy of single-time, multilevel registration in image-guided spinal surgery.

BACKGROUND CONTEXT: Computerized frameless stereotactic image-guidance has been used in recent years to improve the accuracy and safety of pedicle screw placement during spine surgery. Because the possibility of intervertebral motion exists, and because the patient is usually in a different position when preoperative imaging is performed compared with the operative position, it has been suggested that the imaging model of the complete lumbar spine and the surgically exposed lumbar spine may be significantly discordant. Consequently, current protocols suggest registering each spinal level (single-level registration) separately before pedicle screw placement at that level, a time-consuming process. PURPOSE: To assess the accuracy of single-time multilevel registration for multilevel pedicle screw placement during image-guided, computer-assisted spine surgery, in the setting of degenerative disorders of the lumbar spine. STUDY DESIGN/SETTING: This is a prospective clinical and radiological study of 45 patients with degenerative disorders of the lumbar spine who underwent instrumented fusion with the use of single-time multilevel registration computer-assisted, image-guided tomography. The accuracy of the pedicle screws placement was confirmed on the basis of a protocol that included intraoperative spontaneous electromyographic (EMG) recordings, direct pedicle visualization, and computer tomography (CT) scans when clinically indicated during the follow-up period. PATIENT SAMPLE: Forty-five consecutive patients who fulfilled the criteria of computer-assisted, image-guided tomography pedicle screw placement for degenerative lumbar spine disease without overt instability. OUTCOME MEASURES: The principal outcome measure was the accuracy of pedicle screw placement with single-time multilevel registration for multilevel pedicle screw placement during image-guided, computer-assisted spine surgery; postoperative CT performed for clinical indications during the follow-up course was used for the assessment of pedicle screw placement. METHODS: Patients were assessed clinically before and after the operation. Data from 45 consecutive cases of image-guided, computer-assisted lumbar spinal fusion were statistically analyzed to determine the relationship between the number of levels registered during single-time registry and the mean registration error (MRE). Intraoperative spontaneous EMG, direct visualization, and postoperative CT scans were used to assess the accuracy of pedicle screw insertion. RESULTS: None of the patients involved in this study experienced clinical sequelae of improper pedicle screw placement. MREs after surface mapping and after point merge were small (less than 1.00 mm and less than 3.00 mm, respectively). During the intraoperative assessment of the pedicle screws placement, no significant spontaneous EMG activity was recorded and the pedicular walls were found intact in direct visualization. The postoperative CT scans showed in 10 patients accurate placement in 55 of the 57 pedicle screws with expansion of the medial wall in two screws. CONCLUSIONS: Single-time, multilevel registration may decrease operative time relative to repeated, single-level registrations, without compromising the increased accuracy of pedicle screw placement afforded by this technique in the setting of degenerative disorders of the lumbar spine. Despite the advantages in computer-guided image surgery, cautious application in the individual patient is recommended until more comprehensive data can be gathered in specific degenerative pathology with overt instability; thus the knowledge of the anatomy remains crucial.     

Segmental pedicle screwing for idiopathic scoliosis using computer-assisted surgery

STUDY DESIGN: Retrospective clinical study. OBJECTIVES: To evaluate the accuracy of computer-assisted surgery for idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Segmental pedicle screw fixation has been proven to enable enhanced correction of scoliotic deformities. However, both neurovascular and visceral structures are at potential risk from screw misplacement due to pedicle drift. No reports exist on the accuracy and benefits of computer-assisted surgery for pedicle screwing in scoliosis surgery. METHODS: A total of 40 consecutive patients with idiopathic scoliosis were evaluated. Postoperative computed tomography was assessed for the accuracy of pedicle screw placement in 20 cases treated without a navigation system and 20 cases with a computed tomography-based navigation system. Correlations between registered levels and pedicle perforation were investigated. RESULTS: Pedicle violation was observed in 28.0% of the control group and 11.4% of the navigation group, with significant differences. No screw misplacements at the registered levels were seen, and the longer the distance between the registered level and level of screw insertion, the higher the rate of pedicle violation. No intraoperative complications caused by pedicle perforation occurred. CONCLUSIONS: In the navigation group, a tendency to lateral perforation at the concave side and medial perforation at the convex side was noted, like in the control group. Use of the navigation system significantly reduced the screw misplacement rate for rotated vertebrae as compared with the control group. Separate registration is recommended for rotated vertebrae when possible.     

O形臂导航辅助、C形臂辅助与常规徒手置入胸腰椎椎弓根螺钉准确性的定量比较

目的 比较O形臂导航辅助、C形臂辅助与常规徒手置入胸腰椎椎弓根螺钉的准确性。方法回顾性分析2015年2月-2018年12月应用椎弓根螺钉系统辅助融合治疗的129例胸腰椎置钉患者术后CT资料,其中胸腰段以下脊柱骨折41例,退行性疾病88例。常规开放手术直视下徒手置钉(徒手组)42例,C形臂辅助下经皮置钉(C形臂组)46例,开放手术O形臂导航辅助下置钉(O形臂组)41例。从螺钉长度、横断面进钉角度、矢状位进钉角度、椎弓根内侧壁、椎弓根上下壁、椎弓根外侧壁6个方面,采用10分制定量评估椎弓根螺钉置钉准确性,记录得分情况并进行组间比较。结果共置钉712枚。徒手组置钉准确性评分为7.79±0.93,满分比例为7.7%(16/208);C形臂组评分为9.13±0.59,满分比例为51.0%(101/198);O形臂组评分为9.27±0.65,满分比例为62.1%(190/306)。C形臂组和O形臂组置钉准确性评分差异无统计学意义(P > 0.05),但均高于徒手组,差异有统计学意义(P < 0.05)。结论 C形臂辅助经皮置钉和O形臂导航辅助置钉的准确性优于传统徒手置钉,C形臂辅助经皮置钉与O形臂导航辅助置钉准确性相当。     

A free‐hand technique for pedicle screw placement in the lower cervical spine

Objective: To describe a free‐hand method for pedicle screw placement in the lower cervical spine with no intraoperative imaging monitors, and to evaluate the safety of this technique. Methods: A study of the free‐hand technique of cervical pedicle screw placement was conducted by postoperative radiological review and follow‐up. Thirty‐six patients who had had cervical reconstruction with posterior plate utilizing pedicle screw fixation, and been followed for a minimum of 2 years, were studied. The position of the pedicle screw was evaluated by postoperative oblique radiographs and axial computed tomograms. Clinical outcomes were measured by Odem's criteria. Results: A total of 144 screws of diameter 3.5 or 4.0 mm were inserted into the cervical pedicles in 36 patients. Postoperative images showed that 16 (11.1%) of the screws had penetrated the pedicle walls. Among them, 10 (6.9%) screws had penetrated the lateral, 4 (2.8%) the superior and 2 (1.3%) the inferior walls. However, there were no neurological or vascular complications related to the malpositioned screws during a minimum of 2 years follow‐up. In addition, Odem's scores were applied postoperatively in all patients except one with complete neurological deficit. Conclusion: Based on 144 screw placements, cervical pedicle screw insertion utilizing a free‐hand technique without intraoperative imaging guidance seems to be safe and reliable. However, solid knowledge of the anatomy of the cervical pedicle and adjacent neurovascular bundles, and careful preoperative review of cervical images, are imperative for successful screw placement in the cervical spine.     

Extracorporeal single dose and radiographic dosage in image-controlled and fluoroscopic navigated pedicle screw implantation

AIM: Goal of the current study was to compare radiation dose and fluoroscopy time of fluoroscopic computer assisted pedicle screw implantation versus the conventional technique. METHOD: For each of 10 specimens two pedicle screws were placed using conventional technique (group 1) and two screws were inserted with fluoroscopic navigation system (group 2) contralateraly. RESULTS: For implantation of two pedicle screws the mean radiation dose was 0.041 mSv in group 1 and 0.029 mSv in group 2. Fluoroscopy time was 34 seconds in group 1 and 25 seconds in group 2. The differences of radiation dose and fluoroscopy time for group 1 and 2 were statistically significant (radiation dose p = 0.00044, fluoroscopy time p = 0.00039). CONCLUSION: We achieved significantly lower radiation dose and fluoroscopy time with fluoroscopic computer assisted pedicle screw implantation compared with the conventional technique. Concerning exposure to radiation for patients and personnel fluoroscopic navigated screw insertion is to favour.     

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。