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扫描二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:前瞻件、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.常舰组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.

Computer-assisted navigation technique in the spinal pedicle screw internal fixation

BACKGROUND: Recently, trans-pedicle screw internal fixation has markedly improved the rigidity of spinal fixation and hence the fusion rate. But when placed incorrectly, the pedicle screw can injure the spinal cord and/or nerve roots, resulting in serious complications.OBJECTIVE: To evaluate the application value of preoperative CT scans-based navigation technique in the spinal pedicle screw internal fixation surgery.DESIGN, TINE AND SETTING: A prospective, randomized, and controlled observation was performed at the Department of Orthopedics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences between January 2006 and December 2008.PARTICIPANTS: A total of 95 patients who underwent pedicle screw internal fixation due to spine diseases were randomly assigned to a navigation group (n = 45) and a conventional group (n = 50).METHODS: In the navigation group, patients were subjected to pedicle screw insertion with the assistance of computer navigation technique and while in the conventional group, patients underwent pedicle screw insertion using the conventional anatomic landmark combined with fluoroscopy.MAIN OUTCOME MEASURES: Screw channel preparation time, excellent and good rate of screw position, and postoperative complications.RESULTS: In the navigation group, totally 206 pedicle screws were inserted under navigation guidance, with an excellent and good rate of 96.1%; and navigation could not be continued in 9 patients for a three-dimensional registration error. In the conventional group, altogether 285 pedicle screws were inserted, and the excellent and good rate was 100%. No significant difference was found between the two groups (P > 0.05). The navigation group exhibited longer screw channel preparation time than the conventional group [(360±22) seconds vs. (56+8) seconds, P < 0.01]. No postoperative complications were found in each group.CONCLUSION: The preoperative CT scans-based navigation technique produces similar accuracy of pedicle screw insertion, but markedly prolonged operation time, compared with the conventional anatomic landmarks, exhibiting limited application value in the spinal pedicle screw internal fixation.