个体化导航模板在胸椎椎弓根螺钉置入中的初步临床应用

Primary clinical application of patient-specific navigational template for the thoracic pedicle screw placement

中文关键词:  内固定  椎弓根螺钉  胸椎  个体化导航模板  计算机辅助设计  快速成型

英文关键词:Internal fixation  Pedicle screws  Thoracic spine  Patient-specific navigational template  Computer aided design  Rapid prototyping

中文摘要:

  【摘要】 目的：通过临床应用评价个体化导航模板辅助胸椎椎弓根螺钉置入的准确性和安全性。方法：2008年7月~2009年9月，对11例需要行胸椎椎弓根螺钉置入手术的患者（青少年特发性脊柱侧凸7例，先天性脊柱侧凸2例，胸椎结核后凸畸形1例，多发性胸椎骨折1例）术前根据CT三维重建图像利用计算机辅助设计及快速成型技术设计制作46个胸椎个体化导航模板，术中应用个体化导航模板辅助在T2~T12置入椎弓根螺钉92枚，术后CT扫描评价螺钉位置，记录有无与螺钉置入相关的并发症。结果：通过个体化导航模板辅助置入的92枚胸椎椎弓根螺钉中，83枚完全在椎弓根内，9枚穿破椎弓根壁（其中椎弓根内侧壁穿破2枚、椎弓根外侧壁穿破7枚），其中5枚螺钉因椎弓根宽度小于4mm（3.0~3.8mm）而采用椎弓根旁固定方法（椎弓根螺钉轻度穿破椎弓根外侧壁经胸肋关节内侧进入椎体），椎弓根壁非故意穿破率为4.3%，置钉准确率为95.7%，所有穿破椎弓根壁的螺钉的穿出距离均小于2mm，螺钉位置可接受率为100%。无与螺钉置入有关的神经、血管、内脏损伤等并发症的发生。结论：个体化导航模板辅助胸椎椎弓根螺钉置入的置钉准确率高，安全、可行。

英文摘要:

  【Abstract】 Objective：To evaluate the accuracy and safty of thoracic transpedicular screw placement by patient-specific navigational template.Method：From July 2008 to September 2009，46 patient-specific navigational templates were designed and established before operation on the basis of 3D reconstruction of computed tomography image.A total of 11 patients（including 7 adolescent idiopathic scoliosis，2 congenital scoliosis，1 thoracic spine tuberculosis and kyphosis，and 1 multiple thoracic vertebral fracture） underwent spinal deformity correction. Subsequently，92 screws were placed from T2 to T12 in 11 cases by the patient-specific template technique. After surgery，the positions of the pedicle screws were evaluated using CT scan and graded for validation.The complications related to screw placement were recorded.Result：83 of the 92 screws located in the pedicle，while 9 screws were noted to break the pedicle（2 medially and 7 laterally）.Parapedicle screw fixation was performed due to pedicle diameter less than 4mm（from 3.0mm to 3.8mm） in 5 screws.No pedicle screw perforation of more than 2mm was noted.The unintended perforation rate was 4.3%.The accurate rate of thoracic pedicle screw placement was 95.7%，and overall screw acceptable ratio（<2mm breach is safe） was 100%.No screws penetrated the inferior or superior cortex of pedicle in the sagittal plane.No neurovascular and visceral injury related-complications was noted.Conclusion：Thoracic transpedicular screw placement assisted by patient-specific navigational template is safe and reliable.